The Rota Vaccine
As fanciers would be aware we have been running a pigeon Rota virus vaccine trial for the last 6 months. The results of this trial have been reported in this Journal each month as they have become available. I have prepared a chart below showing the full results of the vaccine trial. The 10 trial birds were bled 7 times. The antibody response is tracked below in each bird. Levels above 0.17 are regarded as protective. The birds were vaccinated on the 18th February and the 18th March. A third vaccination was given on the 13th May.
Chart by Dr Colin Walker
What can fanciers expect if they have vaccinated their birds against Rota and their birds are subsequently exposed to the virus? Based on the trial results about 60% of birds will have sufficient immunity to stop them from developing clinical disease ie becoming sick. The remaining 40% will have variable levels of immunity but not enough to fully protect them. Any immunity they have, however, will decrease the severity of the disease. Just how sick each of these birds becomes will depend on the level of immunity they have when they are exposed.
However, it appears that the vaccine may be more effective than the trial results alone indicate. The trial results are not consistent with what has been happening clinically in many lofts. In the trial we have been measuring the amount of antibodies formed in the blood against Rota virus following vaccination. Even though the test is not straightforward it is the usual test that is done to measure immunity. With many diseases like PMV , measuring antibodies gives a good idea of the likely immune response. At the start of the trial there was discussion as to whether or not this was likely to be the case with Rota virus which is primarily a bowel virus. It was thought that even though measuring antibodies in the blood would be useful that there may be an immune response at the bowel lining that may also modify the progress of disease. One suggestion was that trial birds be killed at the end of the trial, that their bowels be removed , samples of mucous be collected from the bowel lining and the amount of immunoglobulins ( another immune mediator ) be measured. Further ways of evaluating the immune response in the trial birds are still being considered. Either way, whatever the immune response is, it does seem as if more than 60% of birds are protected from clinical disease after vaccination.
Throughout June in Melbourne, as fanciers started tossing their birds together, there were outbreaks of vomiting in several lofts. Many fanciers assumed that these outbreaks were due to Rota virus but no testing was done. We were keen to see whether these birds did actually have Rota virus and also if this was the case, did vaccination offer birds some protection from internal damage, particularly to the liver, done by the virus. This can be measured very accurately by drawing blood from the birds and measuring values associated with liver inflammation and function. I was therefore keen to find some droppings from infected birds. Initially a local fancier, who had vaccinated his birds ( two Rotavax 0.5ml 4 weeks apart) rang me and said that about 10 of his 180 birds had started vomiting. Several were quiet and fluffed. I travelled to the loft, collected some dropping and forwarded them to Agribio for a Rota (PCR) test. Two days later while waiting for the results the fancier rang me and said that all of his birds had become well and perhaps it was not worth sending the droppings for testing. The test however had already been initiated and did actually return a positive result. The day after I went to the first loft a second fancier rang me and also said that some of his birds were vomiting. He had about 350 birds and estimated that one in seventy were vomiting. I also travelled to this loft, collected some droppings and forwarded these to Agribio. He had also vaccinated his birds ( two Rotavax 0.3ml 4 weeks apart). Two days later this fancier also rang me. He said that he felt as if he had “cried wolf”. He didn’t think his birds had Rota after all as they had all become well. This test however was also completed and also returned a positive result. A blend of droppings from the first and second loft were used to expose the trial birds to the disease. Despite spending several hours with the birds each day and being a veterinarian I was unable to detect any illness in the trial birds after this exposure. While this was happening, a third fancier contacted me. He had not vaccinated and his birds were now vomiting. I asked him what proportion of his birds were vomiting. He replied, that even though it was not simultaneous, he estimated that over 50% of the birds had vomited. A sample of these droppings were also collected and forwarded to Agribio. They also were positive. Based on this very small sample of only 3 lofts, two vaccinated and one unvaccinated, it does seem as if the benefit of vaccination, as far as reduction of clinical disease in the loft is better than indicated by the trial. We have only tested 3 lofts because the test is expensive and I am paying for them myself. Even though we have only tested 3 lofts other fanciers who have and have not vaccinated and who have experienced outbreaks of vomiting consistent with Rota virus have contacted me and anecdotally it does seem as if the birds that are vaccinated experience a much milder form of the disease if subsequently exposed to Rota virus. The fanciers of vaccinated birds reported that the first sign they noticed was some birds crops not emptying overnight. Vomiting started 3 days after the probable exposure and persisted for 2 to 3 days . In total about 1-5 % of birds vomited . Some droppings became a bit green and wet but overall were not bad. No droppings became watery and mucoid . Birds continued to exercise normally although some were a bit quiet and fluffed. Recovery seemed comparatively rapid. Three days after the vomiting stopped all birds seemed normal. One bird in the first fanciers loft died . All 3 fanciers that we tested have given permission for me to bleed some of their birds. I will do this in about 3 weeks and run complete biochemistry /hematology profiles. The reason for doing this is to compare the amount of internal damage in vaccinated and non- vaccinated birds after a Rota virus exposure. The blood profile that is described in both my book “The Pigeon” on pages 42 and 43 and is also on the APC website in “The Diagnostic Pathway” section will be done. In particular I will be interested to look at the liver parameters. I will also draw blood for the same tests from some of the trial birds. The difference in the results between vaccinated and non- vaccinated birds will be very interesting and will be reported in this magazine next month.
The Rota vaccine, although stimulating an antibody level in 60% of birds that is likely to be protective, and appearing to reduce clinical disease is potentially problematic for fanciers because it does not appear to offer full immunity to all birds. A group of 8 fanciers near me toss together. On one Saturday recently one of these fanciers went to basket his birds in the morning for their combined toss. He noticed that several of his birds had vomited overnight and decided against tossing. Another fancier in the unit tossed routinely. He ended up being 40 out overnight and lost 9 out of about 160. The day after the toss his birds started vomiting. Obviously his birds were just one day behind with their Rota infection . With no obvious symptoms when they were basketed the fancier had innocently basketed them for a long toss while they were incubating Rota with unfortunate consequences. Fancier obviously want and will need to have their birds fully protected from clinical disease before racing starts.
Is vaccinating against Rota worthwhile? Fanciers are familiar with Pox and PMV vaccines that do confer virtually 100% protection from clinical disease and some may think that all vaccines are similar , however not all vaccines are the same. Making a vaccine is never easy and a number of vaccines do not confer full immunity and also need repeated inoculations. It appears as if this is the case with the current Rota vaccine. I am, however, a firm believer that any immunity is good immunity. It will indeed be frustrating however if fanciers will still need to expose their birds to the virus before racing to fully protect them. It is only natural that the immunity formed by exposure to the whole virus will be higher than that formed by exposure to just part of the virus as in the vaccine. The whole point of vaccination is to develop an immunity safely without damaging the pigeons. It will indeed be interesting to see the results of the upcoming biochemistry/haematology tests.
I am interested to hear the experiences of fanciers, who both did and did not vaccinate their birds, after a Rota virus exposure. To some extent what is happening now in Australia is like a giant field experiment or clinical trial. It is the first year that the Rota vaccine has been available to all of us. Such experiences will further help evaluate the vaccines effectiveness. I can be contacted on 0412481239 and email@example.com.
I hope fanciers find my efforts to evaluate the effectiveness of the Rota vaccine useful in guiding the decisions they make with their birds.
Election of National Body Members
In the most recent edition, the July edition, of this magazine, on page 28 was an advert from the ANRPB for the position of Victorian delegate. The advert invited nominations, listed the preferred abilities of an applicant and suggested a resume be sent to the ANRPB assistant secretary. I just wonder what happens next. To me, and I hope that my interpretation is wrong, the advert seemed like an advert for a job in private business and, to me, gave the impression that the Board would then select the successful applicant from any nominations received. I feel that Victorian fanciers must select who represents them. It is not the job of the Board to select Board members but rather fanciers’. Otherwise the Board could simply become a “boys club” where Board members could select members whose views were similar to their own. The election of Board representatives needs to be totally transparent. At the time of writing (July 2020) there is also an advert for the position of Board secretary on the Board website. Here interested persons are invited to contact their state rep and the ad concludes by stating that “All enquiries will be kept strictly confidential”. I can see how such a statement might be added at the end of an advert for a position in private business but am wondering if this is appropriate for a national body for which everything should be totally transparent.
I feel that the whole selection of Board members needs to be reviewed. When do Australian fanciers get to elect the national body that represents them? The attitude of most fanciers that I have spoken to, towards the Board and its members, is one of apathy. Most, however, believe that it would be good to have a representative national body. Some are frustrated and even angry about issues regarding the current Board. When asked “What has the Board done? “, most are aware that the Board was involved in some way in the allocation of the Rota vaccine in early 2019. Some are aware also that in the last 1 to 1 ½ years the Board has celebrated the achievement of pigeons in the First and Second World Wars 75 and 100 years ago. Beyond that, I have not spoken to a fancier who is aware of the Board, rightly or wrongly, doing anything else.
An important tenet of a national body and indeed a major claim of the current body is that it represents the pigeon fanciers of Australia. However under the current system not all fanciers are being equally represented and some are not being represented at all. Given this situation, it is understandable that many fanciers are apathetic.
A big issue currently is the lack of proportional representation. At the moment, the vote of the WA representative carries the same weight as that of the NSW and Victorian representatives (at the moment this position is empty) despite the NSW and Victorian members each representing the interests of 4 to 5 times the number of fanciers. To me, a much fairer system would be to use the delegate system already used by many clubs and federations rather than simply having one rep/one vote per state. In the delegate system, for example, a rep could get one vote for every 50 fanciers he represents. This would mean that WA would get perhaps 2 votes while Victoria and NSW would each get 8 and result in a more accurate representation of fanciers’ wishes.
Another problem is that some fanciers are not represented at all. In states like SA, it is potentially easier to choose a state rep. In SA, most fanciers race in Adelaide and Adelaide only has one racing organization. In Victoria, most fanciers are in Melbourne but in Melbourne there are 5 federations. There are also significant numbers of fanciers and clubs associated with some of the larger rural centres. I would suggest that, if the number of fanciers in rural Victoria were combined, t this number would be similar to the total number of fanciers in WA and yet no one represents these Victorian country fliers. They were not involved in the selection of their state rep in any way. No wonder that they might feel uninvolved and uninterested.
It appears at the moment as if the Board has 6 members of which 5 can vote, although it can be a bit hard to keep track as various members are joining and then resigning. Since 2017, the Board has contained some very experienced and talented members. Many of these have now left, which I feel is a shame. Speaking to some of them, they said that they left because of disagreements within the Board and a feeling that they were just wasting their time.
One difficulty is that the Board is actually a very small group. The difficulty with such a small group is that a non-voter, be it the chair or someone else, can lobby, intentionally or otherwise, the voting members. It is only natural that a non-voter would express his views and that this could influence the vote, particularly of a new less experienced member. This could lead to just a few people, at the moment 5, dictating national policy.
I think it is imperative that any national body needs to develop a good understanding of the members that it is meant to represent. A good starting point, I would think, for an Australian national body would be to find out actually how many fanciers there are and where they live. How can a national body claim to represent the interests of its members or know what the broader pigeon community wants if they don’t survey them or allow them to vote on issues? At the moment, to me, it seems that the Board takes a position and then expects the fancy to follow. After speaking to reps that have left the Board, there seems to be a trend to silence people who have different views.
I think part of the apathy that most fanciers feel for the Board is a consequence of their lack of confidence in its members. Most were not involved in their selection and they feel not involved and removed from the whole notion of a national body. When do we have elections for a national body? Is it not standard for positions to be declared vacant at the AGM and then the positions filled through election? Are the current Board members there until they choose to leave?
When looking to fill positions on the Board, we should not be looking to just put “bums on seats”. If elected by fanciers of a whole state, then election is an endorsement of that person by the state as a reliable representative in whom they have confidence. At the moment, this does not seem to be the case.
Maybe we don’t need to have Board elections. Maybe they would be too hard to organize. Maybe a more workable solution would be that part of the position of a senior committee member in a federation or large club, perhaps the secretary or vice president, would be membership of the Board. Because such a representative would be elected and know the local issues, I feel it is likely that fanciers would feel connected, involved and truly represented. Fancy pigeon owners have already had a very effective national body, the Australian National Pigeon Association, for over 25 years and its organization is not that dissimilar to this where the various state reps are often elected to their local organisations or are elected specifically by them as their national representative. Certainly what can be said is that a much more effective and inclusive system, as well as one that is much more transparent, can be developed than the one that is in place now.
Use of Doxycycline
Doxycycline is a widely used antibiotic in pigeon health management. It is the active ingredient in Doxyvet and one of the active ingredients in Doxy T – 2 products familiar to Australian pigeon fanciers. Doxycycline has poor action against many bacteria in particular Salmonella and E.coli but it is very effective against Mycoplasma and is one of the antibiotics of choice against Chlamydia. Mycoplasma and Chlamydia are commonly involved with respiratory , including air sac infections. Side effects include loss of appetite, vomiting, diarrhoea, suppression of the immune system, liver damage and alteration of the normal bacteria in the gut. Doxycycline can interfere with calcium metabolism in the gut and in bone and so should be used cautiously in young pigeons particularly for an extended time.
Doxycycline does however have many advantages when compared to other tetracyclines such as the “Tricon” and “Aureomycin” that many fanciers will remember. Doxycycline is rapidly absorbed from the bowel, causes less disruption to the normal bowel bacteria, is less affected by concurrent calcium supplementation ( ie less need to remove grit and pink minerals) and provides prolonged therapeutic levels in the blood with a single drink of medicated water providing effective blood levels for up to 20 hours ( compared to about 4 hours for Tricon) . This means that provided a pigeon drinks at least once every 20 hours then the drug is still working. With Tricon the pigeons have to drink every 4 hours including through the night to achieve this (which obviously pigeons do not ).
Some aspects of Doxycycline use warrant further comment.
Doxycyline medicated water turning purple
Fanciers in some areas will notice that water medicated with doxycycline will change from the normal pale yellow to pale pink then red and finally deep purple. This colour change occurs if there are minerals in the water that react with the doxycycline. This change is unlikely to be seen where mains water is used, but is quite common where bore water and other sources of mineral rich waters are used.
As the water changes colour the antibiotic is being inactivated. Solutions for fanciers in affected areas include using either bottled water (not mineral water), distilled or rain water. Alternatively, smaller volumes of medicated water can be prepared that are changed more frequently as the pink colour appears. The whole process is accelerated by heat and UV light. In one interesting situation, a fancier observed that the pink colour appeared less rapidly in his white drinkers than in his black drinkers (that absorb heat). Using lighter coloured drinkers placed out of the direct sun will further help in affected areas.
Concurrent calcium supplementation
Doxycycline absorption from the bowel is reduced if the pigeons ingest supplements that contain calcium, concurrently. To improve uptake of the drug, fanciers should therefore remove grit, pink powder and mineral blocks during medication with doxycycline.
Water acidification during doxycycline medication
Doxycycline absorption from the bowel can be improved if the doxycycline is provided in a weakly-acidic solution. Simultaneously medicating the water with a weak organic acid;, for example, citric acid or acetic acid, will not only enhance the effect of the drug but also make the somewhat bitter doxycycline more pleasant tasting for the birds. Both citric acid (available as a white powder and dosed at the rate of 3gm/6L) and acetic acid (available as apple cider vinegar and dosed at the rate of 5ml/L) are available from most supermarkets.
Doxycycline use and the choice of drinker
Drinkers made from galvanised metal or unglazed pottery will inactivate the doxycycline in medicated water. Drinkers should be made from stainless steel, glass, plastic, enameled metal or glazed pottery.
Mixing other medications with doxycycline
It is sometimes an advantage to treat birds simultaneously with several medications. Doxycycline can be safely mixed with all of the canker medications and also toltrazuril (for coccidia) eg Baycox, Toltravet. It is best, however, not to combine doxycycline with enrofloxacin ("Baytril"), wormers (for example, moxidectin) and multivitamins. Doxycycline should not be mixed with sulphur-based antibiotics as these directly interfere with the effectiveness of the doxycycline. Also if doxycycline is mixed with probiotics then, like other antibiotics,the doxycycline will interfere with the function of the probiotics before they exert their beneficial effect.
Giving doxycycline combined with bacteriocidal (ie antibiotics that kill bacteria as opposed to those that just stop bacteria reproducing) antibiotics such as penicillins (for example, amoxycillin) and fluoroquinolones (for example, "Baytril")
Doxycycyline is a bacteriostatic antibiotic (eliminates infection by stopping bacteria replicating) while amoxycillin and "Baytril" are bacteriocidal antibiotics (eliminate infection by actually killing the bacteria). Giving bacteriostatic and bacteriocidal antibiotics together does not work well. This is because the bacteriostatic antibiotics stop the bacteria from replicating and it is when the bacteria are replicating that they are vulnerable to the bacteriocidal antibiotics. As an example, most authorities agree that giving doxycycline
with "Baytril" reduces the effectiveness of the "Baytril" by 50%.
Giving doxycycline with other bacteriostatic antibiotics such as tylosin and spiramycin
Like doxycycline, spiramycin and tylosin are both bacteriostatic antibiotics. They do not interfere with the action of each other. In pigeons they are commonly used together when combined infections, such as those that occur with respiratory infections, are suspected. Common brands are DoxyT and TripleVet.
Doxycycline compared to other tetracyclines
Doxycycline varies from other tetracyclines, such as chlortetracycline and oxytetracycline, in its therapeutic activity, in a number of ways. The three most important ones are :
1. Longer activity in the blood after a single dose – if a pigeon is dosed in the drinking water with doxycycline, each dose persists in the blood and exerts a therapeutic affect for up to 20 hours. Other tetracyclines only provide effective blood levels for about 4 hours. As pigeons rarely drink every 4 hours and certainly don’t drink through the night this means that doxycycline provides more consistent effective levels in the blood which, in turn, means the birds respond to medication and recover more quickly.
2. Disruption of normal bowel bacteria – doxycycline causes less disruption to the normal bowel bacteria than other tetracyclines.
3. Concurrent calcium supplementation – the effect of doxycycline is less affected by concurrent calcium supplementation.
4. Rapidly absorbed from the bowel.
Because of these benefits doxycycline is the preferred tetracycline prescribed by many avian vets.
Doxycycline compared to enrofloxacin ("Baytril")
"Baytril" is used by some fanciers to treat respiratory infection due to Chlamydia. Doxycycline is a more effective treatment. "Baytril" stops the Chlamydia organism replicating itself and leads to a clinical improvement in the birds; that is, they appear to get better, but while treatment with "Baytril" improves the birds, it may not clear the carrier state. Relapses are common. Doxycycline not only stops the Chlamydia organism replicating, but also clears the organism, resulting in a more successful and targeted treatment.
Dose of Doxycycline
The dose of Doxycycline is 25 -50 mg orally over 24 hours. For Doxyvet this works out to be 3g (one level teaspoon ) to 2 litres of water
An Interesting Case.
I had a fancier contact me recently . His pigeons looked very well but occasionally developed profuse and watery droppings. Figure 4017 shows his birds droppings as they are normally. Figure 4080 shows the droppings when they are watery. He was sure that a disease was present. The birds did not have diarrhoea. The droppings were watery because they contained a lot of urine. This occurs either when the pigeons are drinking a lot or alternatively when the pigeons are drinking normally but there is a problem with the kidneys causing them to lose the ability to concentrate urine and conserve body fluids . A common cause of pigeons drinking a lot is being given supplements that contain excessive sugar or salt – both of which create a thirst. On questioning we realised that the droppings only became wet after he had used a particular supplement . The product in question is a water soluble vitamin supplement. It has been around since the 1970’s. I was surprised to still find it on the market. On checking I found it is available on line and also through some produce stores. The person selling it the fancier advised that it was really good and he should try it. He used it himself on his birds. Withdrawal of use of the product resolved the problem. Interestingly the seller advised that he was having problems with his own birds droppings but had failed to make the connection. Fanciers need to be extremely cautious about buying over the counter supplements. They are not regulated. A recent survey presented by an avian vet at an avian veterinary conference revealed that only 20% of over the counter bird products actually contained what was listed on the label. You just don’t know what you are getting . Many of them are based on very poor science to begin with being formulated by “backyarders”, literally. Interestingly the fancier whose birds had the watery droppings also reported that his birds were eating rabbit droppings. In fact, they were more than just eating them , they were actively seeking them out and eating every one they could find. This indicated a pica – where pigeon eat large amounts of unusual substances trying to source nutrients that are deficient in the diet. The supplement in question apart from creating a thirst was leaving the pigeons nutritionally stressed. Picas are discussed more fully in the answer to question 7 in the “Vet Questions Answered” section in this magazine. The supplement in question and others like it are still available and there will fanciers in Australia using it today. Fanciers are most definitely advised to use Australian registered products that have been approved by the relevant authorities after passing appropriate manufacturing requirements and standards
Ask the Vet
1/ Will Moxidectin kill air sac mites and the mite that cause problems on the racing pigeons chest?
Moxidectin at a dose of 1mg/kg will kill mites ( including air sac mites ) but the bald “moth –eaten” area that you see in the centre of the chest of some pigeons is not due to mites. Many fanciers mistakenly believe that this problem is due to mites. The problem is invariably mechanical damage to the feathers due to them being repeatedly rubbed on the edge of a hopper, drinker or trap. The problem corrects with the moult and will not recur with modifications to the offending device. If there is any doubt a skin biopsy can be collected for microscopic examination. We saw this issue in the clinic also when I worked in Belgium last year. After doing more than 100 skin biopsies we have never identified a mite infection as the cause.
2/ Over the years I have had the tip of the tongue drop off. What would cause this ? Could it be canker ?
The only situation that I am aware of where this can have a disease cause is where a mucosal pox vesicle affects the tongue or exposure to some fungal toxins that interfere with peripheral blood supply. It is unlikely to be canker. The tip of the tongue is too exposed for the fragile organisms that cause canker to do this. If it is just the odd bird and they are otherwise well the cause may just be an injury to the tongue.
3/ I feel my pigeons are lacking condition and their wattles are not chalky white but are slightly grey. Do you think this is ornithosis ?
Not all grey wattles are a problem. Flying in rain and billing can remove some of the white leaving the cere with a pink or grey colour tone. Grey however does raise the possibility of a sinus infection. If the sinuses are infected discharges drain through the “slot” into the throat and also under the cere. These can soak into the ceres and stain them. At this time of year the usual sign that will alert you to a sinus infection is increased sneezing in the loft. If there is a sinus infection the most likely cause is Chlamydia/ Mycoplasma which is sometimes described as the ornithosis complex. However bacteria, in particular Klebsiella, and some fungi can be involved. Birds on a vitamin A deficient diet are more prone to respiratory infections generally so it is worth checking that there are adequate levels in the diet. If the cause is unclear the usual tests that would be considered are a blood profile ( as set out on pages 42 and 43 of my book The Pigeon ) ,microscopic examination of a crop flush , Mycoplasma and Chlamydial PCRs and collection of a swab for bacterial and fungal testing.
4/ My birds must have a respiratory infection because they pant a lot after a short fly. What should I treat them with ?
Fanciers often think this and it is reasonable because panting is a respiratory function. However any disease can sap energy and cause an exercise intolerance. Just as often no disease is present and the birds are either hot, fat , unfit , being forced to fly beyond their fitness capability or are struggling to aerobically release energy to the muscles. Only testing can provide the answer. Tests similar to those in the above answer are used.
5/ My pigeons are “not right”. I was suspicious of a food problem. I tested my sorghum and it went mouldy. How can I fix my birds?
Testing grain by seeing if it will go mouldy is not a valid test . The number of fungal spores on a grain is irrelevant. What is relevant is the level of fungal toxin on the grain. The correlation between the number of spores and the level of toxin is very poor. The sorghum may well be fine. If really concerned the grain can be sent to a lab for toxin level estimation. This is a sophisticated test and not something that a veterinarian can do in private practice. This test is also quite expensive . It is important that a fancier’s money is spent wisely. Usually more routine tests are done initially to check for health issues and the toxin level test is only done if these tests fail to identify the cause or suggest that a problem with the food is likely. Once health issues are identified accurately they can be treated in a targeted way.
6/ There is a heap of Adelaide lofts with “Fat eye” right now in addition to many with Rota. What is “Fat eye”? What is the treatment? Can they race with it? Is it contagious?
We investigated this problem with the University of Melbourne when it was first reported in 2017. A full range of tests was done including a Mycoplasma PCR from inside the eyelids and a conjunctival biopsy ( where a tiny piece of tissue is taken from the inside of the eyelid for microscope examination ). Tests showed the problem to be a Mycoplasma infection. The infection runs a natural course of about 5 days. If birds are treated with a mycoplasmal drug such as Doxy T they appear to get better a day or two earlier. Some fanciers use eye drops, particularly ones containing an antibiotic called chloramphenicol. Use of eye drops is laborious. Doxycycline given orally ends up in the tears and is likely to be similarly effective. One would expect that the racing of birds would be compromised while affected. The condition is contagious and one would therefore expect it to be spread through racing and toss units.
7/ My pigeons have started pecking at their own droppings and eating some of them. I give them peas and wheat as well as grit. They are handfed but are given as much as they want. What could possibly be wrong?
Your pigeons are displaying a behaviour described as Pica. Pica describes a desire to eat either inappropriate material or excessive amounts of a particular substance. Pigeons typically do this when they are trying to source a nutrient that is low in their diet. Some pigeons will eat their own droppings. Stock birds that continually peck at perches or appear to be forever foraging are affected. I have seen pigeons deliberately source and eat cobwebs. In pigeons it is most commonly seen as gorging on grit . Affected birds are usually either on a deficient diet or have a health problem that interferes with the digestion and assimilation of nutrients. Conditions that inflame the bowel wall interfere with nutrient absorption and birds can develop this behaviour even on a complete diet. This means that the birds, even though they eat grit or food offered they cannot get the nutrients these contain and become deficient in vital minerals and other nutrients, often at a time when demand is high, such as breeding. The birds try to compensate for this by just eating more grit. Some fanciers mistakenly remove the grit in this situation, which only compounds matters. If a nutritionally deficient diet is provided, the birds may eat unusual substances in an attempt to source nutrients, or gorge on the provided food trying to compensate for its poor nutritional value
Gorging on grit or continuous foraging and ingestion of unusual substances occurs if:
1. the birds are on a deficient or poorly balanced diet
2. the birds are outright hungry
3. the birds have crop or stomach pain
4. a grit-based substrate is novel to them
5. a malabsorption (for example, Salmonella or coccidia) or maldigestion (for example, pancreatic insuffiency) disorder interferes with the assimilation of nutrients.
In healthy birds provision of a complete diet usually stops the problem. I usually recommend APC Multiboost in the water for one day per week and APC PVM pink minerals continually available . This usually solves the problem. In your case providing a wider variety of seeds as well as checking that the brand of grit used is good quality one (ie variety of soluble and non -soluble grits presented hygienically (double sieved , washed and dried by the manufacturer)will be beneficial
Rota Vaccine Trial
Fanciers may recall that, in the last Journal, I reported that the latest blood tests in the Rota vaccine trial had been done on the 16th March. The results showed that half of the trial birds had developed an antibody response that the University of Melbourne regarded as protective. The trial pigeons were then given their second Rotavax 0.5ml vaccination on the 18th March. Since then, the birds have been bled three more times at 2-week intervals on the 31st March, 15th April and the 28th April. Results of all of these blood tests are now back. They show that we still only have five birds with antibody levels that are regarded as protective. The reason for this is unclear. As a means of trying to find a way of stimulating more immunity in more birds, the trial birds will be vaccinated a third time on the 11th of May. Blood will continue to be drawn every 2 weeks to track the level of immunity in each bird.
There are a number of people working behind the scenes in the trial. I would like to thank Professor Amir Noormohammadi of the University of Melbourne, who has been overseeing all of the testing. I would also like to thank Dr Denise O’Rourke, who set up and validated the ELISA test, and Dr Abida Mushtaque and Dr Ling Zhu, who did the laboratory work. I would also like to thank Dr Travis Beddoe of LaTrobe University, who supplied the protein to measure the antibody level in the ELISA test and the original ELISA protocol. Dr Mark White has been a much valued source of technical support and is covering the cost of the testing. The aim of the whole team is to provide pigeon fanciers with an effective way of protecting their birds against Rota virus safely so that their birds do not have to go through disease and ill health after exposure to the virus and risk internal damage that compromises subsequent racing.
I have no financial interest in the vaccine. It is, however, my strong belief that it is much more preferable to perfect a vaccine rather than simply fall into the cycle of deliberately exposing healthy young birds to a debilitating disease each year caused by a virus that kills liver cells and causes damage that in some birds is irreversible. It is perhaps disappointing at this stage to have only five birds that are likely to be immune but it is worth noting that the other birds in the trial do have some immunity that at least will decrease the severity of the disease they would get after a Rota exposure. We will keep on with the vaccine trial and further results will be reported next issue.
Treatment of Rota virus
If your birds are unlucky enough to catch Rota virus, they will benefit from treatment. Treatment of Rota virus should not be expensive. In summary, the most important things to do are to put an electrolyte/ sugar preparation (eg Electrolyte P180) in the drinker and a probiotic (eg Probac) on the food as soon as the outbreak is detected. Details are explained below.
General treatment principles
There is no specific treatment for Rota virus infections in people or other animal groups. In particular, antibiotics and antiviral drugs are not thought to be of benefit. Preventing dehydration is the biggest concern. This is also the case with Rota virus infection in pigeons. Treatment is supportive. Supportive treatment aims to keep sick birds alive and minimise viral damage while the virus runs its course. This is achieved by keeping birds hydrated and in a positive energy balance so that normal body functions can continue. In our experience, the treatments that seem most effective are oral rehydration preparations and probiotics.
Oral rehydration preparations
Diarrhoea and vomiting that come on severely and suddenly, as occurs with Rota virus, where death can occur within 12 -24 hours of the onset of symptoms, can cause a quick loss of fluid and electrolytes. Using a specifically formulated veterinary rehydration preparation containing a balance of sugars and electrolytes would be expected to reduce mortalities. When managing a Rota virus outbreak, a rehydration fluid should be given as soon as symptoms are noticed and continued until signs have abated (about 7 days). The Australian Pigeon Company produces Electrolyte P180. This is a blend of electrolytes and simple sugars that is registered in Australia for specific use in pigeons. Originally developed to treat distressed race birds on return, it is proving very useful in the treatment of Rota virus
Probiotics are thought to protect the bowel from disease in a number of ways - by producing protective slime layers, maintaining a weakly acidic environment, setting up a physical barrier of bacteria, preferentially occupying receptor sites etc etc. It is therefore reasonable to presume that probiotics would be of benefit in treating birds with a Rota virus infection. Their use may lead to reduced penetration of the bowel by the virus and aid in reducing mortalities. The Australian Pigeon Company produces one of the two brands of probiotic registered for use in pigeons in Australia, Probac.
Bacterial infections are identified in 10-30 % of Rota virus cases (depending on the area), and almost all are heavy pure E.coli infections in the liver and kidney. In these cases, the E. coli did not cause death. Birds die of overwhelming Rota viral hepatocellular necrosis (death of liver tissue). It does, however, seem reasonable that, by treating a concurrent E. coli infection, some birds are more likely to recover. Essentially we still don’t know if this is the case. Some lofts that have experienced high mortalities have given antibiotics while some lofts with low mortalities did not give antibiotics. I guess all we can say at the moment is that there is no correlation, when looking at cases confirmed by the larger pathology services, with antibiotic use and the mortality rate. Antibiotic use should perhaps be reserved to treat individual birds assessed on an individual basis.
Other treatment considerations
Giving a live vaccine such as the ND4 for PPMV can stimulate the release of an immune mediator called interferon. This may give some protection against other viruses for a period of time. Vaccinating birds at risk, for example birds housed near a Rota-infected loft, before they start to show symptoms may be of benefit.
Anecdotally fennel tea has been shown to help stimulate crop emptying and maintain normal bowel function. Fennel tea can be purchased from health food stores. Simply make a cup of fennel tea as you make a cup of normal tea for yourself. This can then be added to the drinker. There is no strict dose rate. It smells like licorice but, unless mixed too strongly, the birds drink it readily. Chlorophyll, the natural substance that makes plants green, also available from health food stores, has also been shown to stimulate the crop to empty. The green powder can be added to the drinker until the water turns pale green.
Current treatment recommendations for treatment of Rota virus
Mildly affected birds can be managed as a flock. For the flock, the most important things are to maintain hydration and electrolyte balance and protect the normal population of bowel bacteria.
1/ Consider using probiotics on the food or in the drinker. I prefer to place probiotics on the food as they are fragile and can deteriorate in the drinker. Seed can be pre-moistened with a seed oil before the probiotic is applied and the grain prepared immediately prior to feeding.
2/ At the first sign of symptoms, start a rehydration solution, eg Electrolyte P180, and Fennel tea in the drinker.
3/ Grit, pink minerals and bentonite clay-based mineral blocks should be readily available.
4/ Do not give antibiotics on a flock basis.
Recommendations to treat individual unwell birds
The following treatment suggestions tend to be reserved for individual birds of value. The amount of treatment offered is often determined by the genetic or financial value of the bird we are treating. An untried young cock bred off one of the lesser pairs might be culled if severely affected by Rota while a fancier would want to offer much more treatment, for example, to a young stock hen that had already bred several fed birds The more severely affected birds often stop eating and drinking. With Rota virus, this can lead to a rapid decline, with these birds becoming dehydrated, hypoglycaemic (low blood sugar) and hypothermic (low body temperature). Unless these processes are corrected, they quickly progress to a fatal end. With correct management, these trends can be reversed in some birds. What a fancier notices in the loft is a bird that becomes fluffed up, reluctant to move, has vomiting and diarrhoea and often goes to a corner. Because of the rapidly progressive nature of this disease, prompt action is imperative. By far the most important thing is to keep the bird hydrated and in a positive energy balance by keeping its blood sugar level up. The crop of the individual unwell bird that is severely affected must always have fluid in it ready and available for the crop to push through into the bird’s system. If an unwell bird is not voluntarily drinking enough fluid to achieve this, then the crop must be topped up with fluid given via crop tube. This is critical to prevent a fatal dehydration developing. I have seen individual birds saved simply by diluting Electrolyte P180, diluted at 1 measure to 2 litres of water and repeatedly filling the bird’s crop, as it empties, with a crop tube. The electrolytes and fluid combat the dehydration while the simple sugars are passively absorbed through the lining of the digestive tract directly into the blood stream.
If individual birds stop eating, they can be provided with an easy-to-digest, high-energy vitamin and mineral-rich liquid food that is given via crop tube. A common brand is Passwell’s Hand Rearing Food. Details are below. These foods are usually offered frequently in smaller amounts. Debilitated birds often have delayed crop emptying. If the crop is distended by eating a large meal in a bird that is already nauseated, this seems to trigger a vomiting reflex.
1/ Most avian vets find it easiest to crop-feed debilitated birds with commercially available hand-rearing formulas made for seed-eating birds such as parrots eg “Passwells Hand Rearing Food”, which is available from most pet shops and all bird vets. Being formulated for an immature growing bird, they are easy to digest and contain higher levels of vitamins, amino acids and minerals than those found in adult rations. These formulas are ideal to treat pigeons debilitated with diseases such as Rota. These preparations are available as powders. Warm water is added until a smooth creamy preparation is produced. This is fed via crop tube.
Formulas are made more dilute if the crop is slow. Also if the crop is slow, smaller amounts are given more frequently.
2/ If the crop is emptying, rehydration solutions can be given via crop tube. If crop stasis has occurred, injectable solutions can be given using standard veterinary techniques and volumes.
3/ Give antibiotics – not used to treat a team usually but can be used in individual sick birds. If the birds are vomiting or the crop is slow, these will need to be given by injection.
4/ Pigeons with slow crops often develop elevated trichomonad levels. Including a nitro imidazole (canker medication) in the treatment protocol may be of benefit.
5/ Place into a veterinary hospital cage set at 20 -23°C with supplemental oxygen (usually at a veterinary clinic).
Many fanciers are probably aware of the “Yellow Drops” marketed by a number of pigeon product supply companies and recommended by several high-profile European veterinarians. The drops can be applied to the nostrils or the mouth and are advertised as having antiseptic properties, clearing bacteria, fungi and other infectious agents from the mouth and upper airways. They also are advertised as clearing any mucous from the sinuses. Certainly after application, a significant amount of mucous comes away through the “slot” and nostrils. The active ingredient is acriflavine. “Yellow drops” are used by many European fanciers who use it as a general disinfectant for the nose and throat. A prominent European vet explained to me that it works well once these areas are free of infection, to maintain and keep them clean. He advised that the drops do not replace antibiotics in the presence of actual infection. Acriflavine’s use is attractive to some fanciers because acriflavine is a plant extract. They see its use as preferable to that of a “drug”. Some fanciers mistakenly believe that application of the drops to the nostrils causes pre-existent mucous to come away, in the process making it easier for a bird to breathe and therefore be more competitive when racing. Being irritant though, it is the application of the drops that actually stimulates the production of the mucous, which then comes away. My vet friend says that he recommends that, if a fancier wants to use the product, it be placed into the nostril and never the mouth. He said that he has seen birds where even a small amount got into the windpipe and birds then coughed for the rest of their lives. Another Belgian vet also said that it works very well to keep the throat and upper respiratory tract clear of infection once the birds are negative for infections and also added that it should only be applied to the nostrils. Use of the drops is labour intensive as a drop needs to be applied to each nostril of each bird in the hours before basketing. The fact that it is irritating to the point that it causes the production of mucous, which then has to be sneezed and coughed away, bothers me. I also feel that any topical antiseptic benefit would be mild and transient. Fanciers will need to decide whether they want to use this product for themselves but I will not be using it on my own birds.
Preparation for Racing.
It is now looking increasingly likely that we will be able to race our birds this year, even if the season has a later start or is shortened. With this is mind, it is a good idea to start to think about what we should be doing with the birds, apart from vaccinations, to prepare them for racing, from a veterinary point of view.
Pre- race health Program
Principal aim: Having allowed as much time as possible for the birds to form their natural immunity, it is now a matter of assessing what health problems are persistent and then using drugs, if necessary, to get the birds completely healthy before the first race.
In the first few months of life all the fancier really needs to do is just let the pigeon grow up in a healthy environment. This is achieved by making sure that the birds are parasite free, fed a nutritious diet and that the loft is kept clean, dry and not overcrowded.
The veterinary attitude toward health management changes 6-8 weeks before the first race. Up until then, apart from parasite control, medication is avoided unless the birds in themselves become unwell. Sub-clinical levels (non-disease-causing levels) of various potential health problems, in particular wet canker and respiratory infection, are tolerated so that the birds, through exposure to low-grade disease, can develop as strong a natural immunity as possible to them.
In many well-managed lofts, the birds’ natural immunity will be such that, when screened for disease in the last weeks before racing, none is apparent. However, as racing approaches, it is important that any identified health problem be eliminated. I recommend that before fanciers embark on their final long tosses before the first race, and preferably several weeks earlier, droppings and birds be taken to a bird veterinary clinic for a health profile. By this time, the birds have been given as long as possible to build up immunity. Testing reveals any persistent problems; these are then treated so that the season can be started with healthy birds.
For fanciers who are not able to get to an avian vet, droppings can be mailed in. Dropping analysis primarily checks for worms (hairworm and roundworm and sometimes tapeworm) and coccidia. Dropping analysis also gives an indication as to the general health of the birds. Presentation of a live bird enables a more accurate assessment, not only of wet canker and respiratory infection but also of less common problems such as Hexamita (a canker-like organism that lives in the bowel).
Common health problems and how to control them before racing starts.
Before the start of racing, it is essential that the birds are parasite-free. To this end, if parasites are detected in the droppings, or a dropping analysis is not possible, the following protocol can be adopted:
• For hairworm and roundworm, external mites and air sac mites: moxidectin, 2mg/ml, 5ml to 1 litre for 24 hours.
• For tapeworms: moxidectin with added praziquantel; e.g. Moxidectin Plus, 5ml to 1 litre for 24 hours.
• For coccidia: toltrazuril; e.g. Toltravet, 25mg/ml, 5ml to 1 litre of water on days 1, 2, 8 and 9.
• For lice : I find it easiest to simply put moxidectin at 1/10 the oral dose, ie 1ml /2 litres, in the bath water
In the last few weeks before racing, a selection of birds from the race team should have crop flushes done to make sure that they are not still carrying trichomonads (that is, have wet canker). In many lofts, the birds will have developed a good immunity and no trichomonads will be found. If any trichomonads are found, the birds will need to be treated. We want to start the season with healthy birds. Having given the birds as long a time as possible to develop immunity, any persistent infection is cleared with a medication course, such as ronidazole or dimetridazole for 5-7 days. If this is extended to a 7-day course, this will kill any Hexamita present.
3/ Respiratory infection
As racing approaches, the birds have been given as long as possible to develop their natural immunity. It is important, however, that there is no active respiratory infection in the birds when racing starts. This can lead to poor race results and potentially disastrous returns. Chlamydia and Mycoplasma tests can be done by your veterinarian to see if these diseases are still active and if the birds have formed a good immunity. The usual tests available are the Chlamydia Immunocomb and a Chlamydial and Mycoplasmal PCR.
A team should be treated for respiratory infection before racing if it fits into one of the following categories:
1. If testing shows that the disease is still active in the birds, even if they look normal.
2. If respiratory infection was a problem during the early part of the racing season the previous year and the loft parameters have not changed (i.e. same loft design, same genetics, etc.).
3. If there was a significant amount of respiratory disease in the post-weaning time.
4. If the birds have a current visibly obvious respiratory infection.
The most common medications used are the antibiotics doxycycline, tylosin and spiramycin. The length of treatment depends on the severity of the problem and response to treatment, but treatment times of 7–20 days are usual. These courses are usually finished several weeks before racing starts and are best followed by probiotic supplementation. If the birds do not fit into one of the above four categories, then no treatment is required.
Problems with Vaccinations.
Over the last few weeks we have had fanciers report pigeons becoming unwell after PMV vaccination. We have autopsied several of these birds. Fanciers were concerned that there was a problem with the vaccine or that there may have been some underlying health issue that was exacerbated by vaccination. The birds we autopsied all had infections around the site of inoculation, apparent as large cheesy lumps and in most cases the infection had then entered the blood stream and caused infections at other sites in the body. In one case a bird had yellow flecks of dried pus and fluid associated with a bacterial infection in an abdominal air sac. Another had a similar infection around the heart. When a severe localized infection develops it is not unusual for bacteria to enter the bloodstream ( something called a bacteremia) and from there be carried to other parts of the body. Fanciers are reminded to take every care to maintain hygiene when vaccinating their birds against Rota and PMV. If the needle becomes contaminated between pigeons with dust from the loft, or is touched or is injected too deeply into the crop then it will be contaminated with bacteria and infect subsequent pigeons. The tip of the needle should go just below the skin and when correctly injected a white ‘flare’ should be seen just below the skin. There is no need to attempt to sterilise the skin with disinfectant as pigeon skin is virtually sterile anyway. If concerned, fanciers should just change the needle every 10 or so pigeons or whenever they think it may have become contaminated. Needles literally cost less than 5 cents each. This means that even if the needle is changed for every pigeon it costs less than $5.00 for 100 pigeons. Hardly a big expense. If a bird does appear unwell after vaccination it is a good idea to give it antibiotics. This will not affect the action of the vaccination and prompt treatment may prevent a bacterial infection starting that could either compromise or kill the bird . Baytril, 0.4 ml once daily orally for 5 days is a good choice but of course consult with your avian vet first.
Rota Vaccine trial.
The Rota vaccine trial has commenced. The trial is more of a pilot study than a full trial. To do a full trial would delay initial results and may be more than fanciers need right now. For example, I have been advised that a full trial would involve submitting a detailed plan in writing to the appropriate authorities for review (this could take months), having a data logger on the container that is used to transport the trial vaccine, using a measured volume of vaccine and then returning the balance for reconciliation, etc etc. All of this takes time and money. What we as pigeon fanciers just need to know as best we can now is, does the vaccine work or not? We are better placed to measure antibodies in the blood against the severe high mortality form of the disease, although it still difficult to correlate that to actual protection. Measuring immunity against the milder vomiting and diarrhoea form is harder. In this pilot study, blood was drawn from 10 pigeons of 4 different breeds, from 6 to 16 weeks of age, on the 18 th Feb and tested to make sure that they had no prior Rota immunity. Later that day they were given 0.5ml Rotavax . Blood was again drawn from the 10 trial birds on the 4th March. Blood was also drawn from 4 of my race hens that had recovered from a natural Rota virus infection in April 2018. Blood will continue to be drawn from the 10 test birds every 2 weeks. The birds will again be vaccinated on the 18th March. Over the next 3 months we should be able to develop an immunity curve illustrating if immunity is formed and if so, at what level. One thing that we do need though are blood samples from recently infected Rota virus birds. We know anecdotally that recovered naturally infected birds are refractory to reinfection for at least a year. By comparing the immunity in the trial birds with these birds we will be able to estimate to what extent the vaccine is protective. If someone has had a recent confirmed Rota outbreak, it would be good if they could contact me. So far I have been paying all costs involved with the trial. However , as usual, Dr Mark White is being very helpful and has indicated that he is prepared to cover all of the primary trail costs including all laboratory fees. This represents more than 95% of the costs involved. I will continue to cover other incidentals such as postage, nurse salaries etc. and of course there is no charge for my time. Mark will be supplied with a detailed set of results. Results will also appear in my monthly articles in this journal as they become available. Time is of the essence. With long tossing and bird mixing starting in Victoria in May and indeed earlier in other states, fanciers need to know to what extent Rotavax is likely to have protected their birds. The last thing we want is to start tossing and then have the birds get sick, meaning that birds miss early races or are at risk of being sent to races while they are still convalescing. It should be mentioned , however, that this is a pilot study involving 10 birds and is not a full vaccine trial. Any results should be considered with this in mind.
What we are doing in the trial is measuring the amount of antibodies formed in the blood in response to vaccination and comparing these to the levels in naturally infected recovered birds. The difficulty comes in interpreting the results. As yet , the firm correlation between clinical disease, immunity and antibody levels has not been established. Antibody measurement is however the best test available to us. A more precise method would be to have controlled exposure to the virus in birds with different levels of antibody and then monitor their response to see if they were actually immune. This , of course would take a long time and considerable expense. Another factor confounding interpretation is that protective antibodies in the blood may not be protective at the level of the gut. It may be, and I think it is likely, that antibodies in the blood above a certain level will not only stop the birds from dying but also protect the birds from the virus damaging them internally ( ie once the virus has penetrated the bowel) but the antibodies in the blood may not protect the birds from developing mild bowel symptoms like vomiting and diarrhoea caused by the virus in the gut ( before it enters the body). This may explain why the disease appears to be changing from a severe disease that damages the liver with a significant mortality rate to a disease that causes mild , transient vomiting and diarrhea. It is not the disease or virus that is changing but rather that the birds immune response is modifying the clinical symptoms that we see. The birds in the trial will be available for euthanasia at the trial completion. This would enable the measurement of antibody levels on gut secretions . Again however the interpretation of these results would not be straightforward. If birds were euthanized and they had developed clinical symptoms associated with a Rota exposure after vaccination then their livers and other internal organs could be examined microscopically to see if, in fact , the virus had damaged them internally, despite vaccination. Also blood could be drawn from them at any time and biochemistry markers that elevate with liver damage be measured along with other tests. And so, there is a bit of work ahead of us and matters are not quite as simple as some fanciers might believe. The important thing is for fanciers not to over-hype the pilot study. It will give much information but will not provide all of the answers. Results and their interpretation will be released as soon as they become available.
Strange stuff on the Internet
Some of the stuff that is on the internet is incredible. Fanciers need to be wary. The internet can be a good but also a bad thing particularly where personal opinion or experience is replaced with scientific fact.
Two recent examples are below:-
1 I got a cock off my friend he hasn't filled in 2 years and I got a Viagra tablet broke it into 4 give it to him every 2 days and he filled 9 eggs I tried it with another cock and it worked as well two of my mates done it and it worked as well so it definitely does and it's worth a try
Viagra is not an infertility treatment. Viagra dilates peripheral blood vessels in the process causing penile erection. Pigeons don’t have any erectile tissue and the drug has no effect on the testes or sperm production. Bear in mind that the time for sperm to mature in pigeons is 6 weeks so any change seen in fertility before this time cannot be affected by any medication.
To suggest that any single medication, be it Viagra or anything else ,would treat all causes of reduced fertility is naïve in the extreme. Possible causes include testicular infections, cysts or tumours, any health problem that decreases vitality, Vitamin A deficiency , decreasing day length and temp etc etc.
2/ Breathing Cavities. This is a very important attribute, which never seems to be concentrated on for genetic improvement. Like most creatures there is a variation in the nostrils of our racing pigeons. Pigeons with very little nostril membrane are less restricted to oxygen intake when flying at high altitude or speed. The bird with a large membrane will be restricted when flying high or at speed because this membrane closes and forces the pigeon to mouth breath, which in turn makes it thirsty and it will go down for water and you have lost the race. I perform a bloodless operation at some of my seminars to demonstrate how it is possible to improve this defect of nature. Photographs showing this minor operation will be published in my book and will also be demonstrated on my seminars in the United States of America. God Willing.
I don’t think the writer of this means the membrane – this is the tissue layer that lines the various sinus cavities and cere. I think he means the nostril ie the opening of the cere. This technique does not make any sense to me. The nostril opening directs inhaled air over the membranes lining the cere and sinuses. This process warms and cleans the air ( by removing particulate matter ) before it enters the air sacs and lungs. Making the nostril opening bigger would expose these membranes, predisposing them to drying, compromising their function and predisposing the pigeon to infections of the respiratory tract.
PMV and E.coli
When I was working in Belgium last year at a specialist racing pigeon veterinary clinic. One of the common diagnoses was PMV with a concurrent E. coli infection. I had not experienced this with any frequency in Australia. But we are now starting to see this. We have seen about 15 cases of PMV this year. Fanciers have invariably described how their birds drank a lot of water, sat there with big fluid filled crops and there were large wet patches on the loft floor. About 10 % of birds in the outbreaks have died. This is different than the pattern of disease we saw with PMV 6 years ago. Many birds now have some background immunity from vaccinated parents or an earlier low grade exposure . This low level modifies the severity of the disease and causes a different pattern of disease. PMV is the only virus that occurs with any frequency that damages the kidneys. Damaged kidneys can’t concentrate urine leading to the wet patches on the floor and thirst. At autopsy, in addition to kidney damage the birds often have scarring in the pancreas – something that was uncommon before PMV arrived. Many of these birds also have concurrent E.coli infection that presumably are able to establish because of the birds debilitated state. It is likely, I feel, that we will go the same way as Europe with birds that fail to thrive or just fail to come into race condition becoming increasingly diagnosed with PMV/ E.coli. The good thing is that with correct use of the vaccine it can all be avoided.
Some fanciers I feel get so caught up with what is going on in their own back yard or their local club that they almost live in a bubble. I would guarantee that if you asked 95% of Victorian fanciers who won the CCF averages or the SAHPA averages last year they would not know. I think most fanciers would not even know who won championships in other feds in their own cities. This was highlighted to me only 4 weeks ago. A good friend of mine has arguably been the best fancier in my federation over the last 10 years. He has been racing 40 years. He has won many feds and the fed averages more than 5 times. One of his birds was reported by a fancier in another Melbourne fed who had been racing about 25 years. When he arrived to collect his lost bird he was cordially invited in and then asked did he race, had he been racing long and had he had any success. I don’t know what this means for the future of the sport or indeed if it has any ramifications at all but my feeling is that it would be better for the sport if fanciers simply made themselves more aware
Some fanciers are not on mains water. Water coming from a tank can look clear and clean however can be a source of infection. For the first time, we have seen, this year, a significant amount of ill health in young pigeons associated with poor water quality. Young pigeons from several lofts presented with a variety of symptoms. Signs varied from one bird to another within single lofts but all symptoms were due to non- specific bacterial infections. Testing of the water gave the diagnostic answer. It would seem that the persistent hot and often windy conditions led to more debris accumulating on the water catchment areas that drained into water tanks and the accompanying dry periods led to less flushing of the tanks. In one instant a fancier lived near an organic market garden. The poultry manure that was used as fertiliser was picked up by the wind, washed into the tank when it did rain and this water then given to the young pigeons. Some excellent filtration systems are available that remove dirt, sediments, heavy metals, bacteria and viruses if fanciers are concerned.
YBD and Rota
Some European vets and fanciers are reporting a decreased incidence of Young Bird Disease (YBD ) in pigeons vaccinated with a Rota vaccine. It seems that there has suddenly been a plethora of vaccines released onto the market in Europe. There are vaccines for Herpes, Rota, Adeno and Circo viruses. Many fanciers are keen to use them and there manufacturers are obviously keen to sell them. I have been reliably advised that no trials have been conducted on any of the European Rota vaccines so just how effective they are remains unclear. I do not know if any trials are currently underway. The role of Rota virus in YBD also remains unclear. Some fanciers and vets seem keen to make a connection . Fanciers will recall that the pigeon community attributed YBD to many things over many years until we, in Victoria, actually diagnosed Rota virus and told the world that this virus caused disease in pigeons. I think that Rota is likely to be a factor in YBD but until many birds with YBD are autopsied and full testing done ( ie various virus ID techniques used) we will not know the full extent of its involvement. At the moment with the effectiveness of European Rota vaccines unclear and sufficient viral testing yet to be done on YBD cases all that can be said is that the decreased incidence of YBD following Rota vaccination is an interesting observation .
Corona and Rota
It is interesting watching the correlation between the control of Rota virus in pigeons and the control of Corona virus in people. Watching the spread and control of Corona virus is a bit like re living the Australian Rota experience but on a global scale. At the moment everything is focussed on containment, aiming to prevent the spread of the virus so that as few people as possible become unwell or die, while a vaccine is produced as quickly as possible. This is the exact route that we started on with Rota. Already however there are commentators saying that we are all going to get it anyway in the same way that some people advised with Rota. Hopefully Corona won’t go the last step where people deliberately spread the virus and are prepared to accept collateral damage and deaths.
Performing Enhancing Drugs
Uniformity and consistency is being sought amongst Melbourne federations regarding the detection and penalties involved with the use of performing enhancing drugs . One federation in particular has drawn up a well thought out, comprehensive performance enhancing drugs document for inclusion in their rules. Drugs of concern are anabolic steroids, beta agonists, corticosteroids, anti-inflammatory non-steroids, opiates, analgesics, performance enhancing stimulants including caffeine, synthetic hormones, and any drug , substance or compound found to be performance enhancing as well any substance which may be used in an attempt to mask the above. With advancing technology the same labs that do testing in horses and greyhounds have been able to adapt their techniques to test the droppings of pigeons. Testing is done by Racing Analytical Services (RAS) in Melbourne . RAS have advised that it is routine for them to test for all of the drugs listed above except for the synthetic hormones which, if specifically required, would need more thorough testing. RAS’s price for full testing ( excluding the additional tests for some of the synthetic hormones) is $170.50 including GST which I think is quite reasonable. RAS and myself discussed how birds generally metabolise drugs more quickly than mammals and also the fact that it is usually 2 days ( with a Thursday night basketing ) from the time birds leave their loft until they would be available for testing. These factors could mean that drugs that did affect the race outcome could be metabolised and return a negative test result. RAS have suggested that it might be better to test fresh droppings taken from a basket on the night of basketing. Tamper proof sample bags are available through RAS. It is usual to collect A and B samples. And so it seems as if the testing procedure has become quite straightforward. After obtaining some tamper proof bags it would simply be a matter of collecting some fresh droppings from an entrants basket during basketing and forwarding these to RAS. In Melbourne the proposed penalties for the use of prohibited substances are severe and include a 3 years ban from racing.
If pigeons were treated with an anti –canker drug for an extended period and were then repeatedly tested, via crop flush, for canker, one would rightly expect these tests to be negative. And yet if these tested negative birds, were then placed in a new basket by themselves with all new equipment that had never been near a pigeon, they could redevelop a canker infection. How can this be?. Canker organisms feed on bacteria and usually reproduce themselves asexually by simply dividing in two. No canker drug will kill every last canker organism in a pigeons crop. If the pigeon does not have good immunity to canker the canker infection will re-establish. This highlights the incredible importance of
1/providing good ongoing care to the young pigeons while they are maturing so that their immune systems are working well and are able to develop a good natural immunity to all of the common disease causing agents and
2/ using medication correctly—the drugs available to fanciers are very effective and using canker as an example, regularly treating for canker in young pigeons will certainly keep them free of canker but at the same time they are not getting the ongoing low grade exposure to the organism they need to develop an immunity and will therefore be much more vulnerable to wet canker flare ups in the racing season.
Nothing beats ongoing good care when considering the maintenance of health in pigeons. Medication is used during the times when disease gets the “upper hand” or through periods of stress when the birds natural immunity may not be enough to protect them. It is the pigeons strong natural immunity that keeps them well in the longer term and not drugs.
Eating Grit Not Necessarily Good.
Certainly pigeons that are on a diet that is deficient in some of the nutrients that a grit may contain will initially gorge on it but just because pigeons want to eat a lot of a particular type of grit does not necessarily mean that that grit is good for them. Pigeons do not have nutritional wisdom. They simply eat things that taste nice to them . A good example here is a grit with a lot of salt on it, even though it is not good for them, pigeons will eat a lot. Also if a grit is poorly formulated nutritionally, pigeons will often eat the amount that satisfies their nutritional requirement for the lowest nutrient in the grit. In order to get enough of this nutrient, found in low levels, they will eat a lot of the grit, in the process, taking in an excess of every other nutrient sometimes approaching toxic levels. We see this most commonly where pigeons take in toxic levels of iron. So , don’t base a grit’s quality on whether the pigeons are keen to eat it or not. A good quality grit should be sieved to an appropriate size, washed, heat treated , contain a variety of grits and have no excess salt. It should be palatable and eaten by the birds but they should not want to gorge on it.
In Victoria most youngsters are weaned between the beginning of November and the beginning of February. Most states, however, wean a bit earlier due to the timing of their race seasons and the weather. For all fanciers , no matter what exact month it occurs, weaning is an important time. Although when weaning babies, racing can seem a long time away it is obviously vital that the developing youngsters receive a good start to their careers in the racing loft.
During the post weaning time we don’t like to use much medication. It is essentially a matter of providing ongoing good care and letting the birds mature. When disease does appear it is usually as a result of some management or environmental flaw that places the developing young birds under stress.
If disease does appear it can be divided into 4 categories :
1/Canker. Young birds require exposure to canker as they mature in order to develop a natural immunity to it. Over treatment in the post weaning time means the birds don’t have the exposure they need, don’t develop a strong immunity and are therefore more vulnerable to wet canker flare ups with the inherent stresses of the upcoming race season. Fanciers will be familiar with the thick yellow scum that occurs in the throat of an affected youngster. If possible individual birds should be treated. In Australia, four different brands of tablets, each with a different active ingredient are available for individual bird treatment. Alternatively, the unwell youngster’s water can be medicated. In Australia there are two different drugs available as water soluble powders. It is important, however, to ensure that the unwell youngster is still able to drink. The group of youngsters, as a whole, should only be treated if more than 10% of youngsters are showing signs. This however is only likely to be necessary if the group of youngsters is under some stress. They will respond poorly to any medication unless this stress is identified and corrected. Do also bear in mind that not all yellow scum in the mouth is due to canker – many viral infections in particular, cause this to form. Also not all birds with canker will have yellow scum. Some for example may just have slow crops.
2/Respiratory signs. In young birds, a respiratory infection usually appears as either a dirty cere or a ‘one eye cold’. Sneezing is a good indication of respiratory infection in young pigeons (because it indicates that something is irritating the sinuses) but this can occur with very mild disease and during the post weaning time is not an indication for treatment. Most young bird respiratory infections are primarily due to an intracellular bacteria called Chlamydia , but are often complicated by concurrent Mycoplasmal and bacterial infections. The usual antibiotic used to treat respiratory infection in young pigeons is called doxycycline, although others are available. The same basic principles that apply to canker treatment apply to respiratory infection. Birds should only be treated if the infection progresses to the stage where it is compromising their development. Flock treatments should be avoided if possible, with treatment focused on treating individuals. We try and let the birds have some exposure to the various organisms in order to stimulate the development of a natural immunity. Severely affected youngsters can have trouble looking after themselves in the loft and should be separated. Mildly affected birds are left in the loft. Unwell birds are often treated with doxycycline 25mg once daily (in tablet form). If more cases are developing every day, or more than 10% of youngsters are affected the flock can be given doxycycline 12% (e.g. Doxyvet) 3g/2L of water. However, in this situation it is likely that there is some underlying management or environmental flaw which will need to be corrected to prevent ongoing problems. Some fanciers ring me concerned that their birds may have respiratory infection because there appears to be an increased amount of mucous in the throat. I personally find the presence of mucus in the throat an unreliable indicator of respiratory infection in young pigeons. All pigeons have approximately 1.5ml of mucus in the throat all the time. The level of mucus may increase with respiratory infection but this is difficult to quantify. Similarly, I am cautious in diagnosing respiratory infection if the birds pant after exercise. Birds with respiratory disease may pant excessively but this is affected by too many other factors, such as the stage of the moult, level of fitness and heat of the day, to be a reliable indicator.
3/Bowel signs. Look for discolored droppings with a higher than normal fluid content. Affected youngsters are usually quiet and underweight. In days gone by, the three most common causes were coccidia, ‘thrush’ and bacteria such as E.coli and Salmonella although worms were a problem in some lofts. These day, however, the appearance of wet droppings is often the initial indicator of either a Rota, PMV or other viral infection. Microscopic examination of a faecal smear is a good diagnostic starting point to determine the problem. If coccidia is involved, then the entire group of youngsters can be given toltrazuril (e.g. Toltravet) 25mg/ml, 5ml/1L on treatment days 1, 2, 8 and 9). This does not interfere with developing immunity. ‘Thrush’ can usually be successfully treated with probiotics. Treatment of bacterial infections is more complex and involves the use of antibiotics, disinfection and sometimes vaccines. These problems are rarely however simply fixed with drugs. Their presence can reflect loft stresses, which will need to be corrected to stop the ongoing need for medication.
4/Very sick or dying youngsters. Here affected birds are fluffed up, reluctant to move and are often underweight, with a reduced appetite. The diseases mentioned earlier can, in their most severe forms, appear like this and usually testing for these is done initially. However, the generalised form of paratyphoid, Aspergillus (a fungus that affects the respiratory system) and the viral diseases Herpes virus, Adeno virus, PMV, Rota and Circo virus, must be considered. Often, one or more birds need to be submitted for autopsy and the relevant tissues and other samples submitted for examination by an avian pathologist or laboratory. It is worth noting however that the signs displayed by pigeons with both PMV and Rota are changing. In particular with PMV when it first got into Australia in 2011 the main symptom was that the birds just started dying. These days most birds, including non- vaccinated youngsters have some immunity. This modifies the severity of the symptoms. Often birds with PMV will drink a lot, have big fluid filled crops and produce wet droppings made up, not of diarrhea, but dilute urine, that appear as large wet patches on the loft floor. In some situations not many birds die. However PMV remains the most common cause of significant mortality in pigeons. Occasionally we still see mortality rates of over 80 %. Whenever more than 10 % of a group of pigeons die PMV should be suspected.
It is worth mentioning the inherent risks associated with squeaker sales. I think it is very fool hardy to buy youngsters from a sale and bring them home to your racing loft unless your youngsters are vaccinated.
No health problem can be effectively resolved if there are ongoing stresses affecting young pigeons. Many normal features of the young pigeons’ existence, such as moulting and establishing their perch in a new loft, not to mention persistent falcon or hawk attack provide unavoidable stress. Most growing pigeons can tolerate a single stress but, when stresses start to overlap, opportunistic infection can take advantage of the birds’ weakened immune system and the youngsters can become sick. In addition, in some areas the weather during these months is changeable and humid: conditions that favour the spread of disease.
Overlapping stresses in the form of environmental or management flaws, or failure to control primary diseases such as parasitism, can trigger a disease outbreak. Occasionally, however, in the best lofts under good managers, disease will occur despite good control of young birds’ stresses.
Ways that fanciers can minimise stress in their young birds include:
Avoiding overcrowding. Ideally, no more than 25 birds in a two-cubic-metre section.
Providing a seed mixture of good quality and in adequate quantity, given at regular intervals. The seed should be clean, free of dusts and moulds, and contain sufficient levels of protein for growth and moulting and be given in sufficient quantity. I work with a basic mix of about 35% dun peas, 18% safflower, 20% corn, 12% milo, 10% wheat and 5% small seeds.
Providing grit and a pink mineral.- Grit should always be in front of the growing youngster. It contains the calcium that is vital for the formation of a healthy skeleton. A pigeon is independent at four weeks, and can reproduce at six months. This is analogous to a human being full-grown at five months of age and sexually mature at two and a half years. With such a phenomenal growth rate,
nothing must be lacking. The bones are genetically programmed to increase in size and if calcium is lacking they will not be as strong as they should be. Pink minerals provide not only calcium but also a range of vitamins and minerals. Regular use of a water-soluble multivitamin is also useful. No seed blend, no matter how many different seeds are used or in what proportion can supply all of the vitamins ,minerals and amino acids required in a complete diet. Racing pigeons are not given the opportunity to forage over wide areas for extended times and so the fancier must supply all necessary nutrients. Providing a complete vitamin, mineral, amino acid supplement in the water for one or two days per week just makes good sense. Fanciers do however need to be careful when selecting the brand of pink minerals and vitamins they use. The manufacture of these is poorly regulated. Some are produced by back yard operators with no qualifications. An example is a brand of pink mineral that I see advertised which contains probiotics. This is a nonsense. There are only 2 probiotic products registered for use in pigeons in Australia . These are the Australian Pigeon Company’s “Probac” and Vetafarm’s “Probotic”. Probiotic bacteria are fragile. They are supplied in sealed jars that must be kept below 30C. My advice when using them is to add them to the drinker just before calling the birds in from exercise and feeding so that the birds will go to the drinker straight away and drink them. Similarly, if applying to the food, they are added freshly to the grain immediately prior to feeding. The idea that they can be put into a dry salt containing powder such as a pink mineral, be stored for months and then be alive and beneficial is just silly. Salts are used to kill bacteria and the fragile bacteria in probiotics are also killed by exposure to light, heat and just time. How can something that has been stored is a salty powder and then put out in an open container on a loft floor indefinitely be affective? That is why the product is unable to be registered. Fanciers are just wasting their money. Fanciers are encouraged to use products that are registered in Australia from veterinary companies.
Enabling adequate rest periods. The young bird must develop a bond with the loft and a perch within it, and must feel secure when there. People tell me that pigeons get used to anything, such as backyard dogs, incinerators, and kids playing directly in front of the loft, but I think, drawing an analogy with some people that live on a busy road, that just because they get used to it does not mean they like it.
Providing a good loft. Essentially, a pigeon loft must be dry without being dusty and provide adequate ventilation without exposing the birds to extremes of heat and cold.
Keeping the loft clean. Regular cleaning removes germs and provides a healthier environment.
Keeping groups of young birds together. Young birds will form groups within the loft as part of their basic flocking instinct. Fanciers may note that youngsters weaned on the same day may still be sharing the same section within the loft as adults. Young birds are easily intimidated by older birds.
Controlling internal and external parasites. Both internal and external parasites drain the body of nutrition that would otherwise be available to the growing youngster. These days most people are familiar with medications such as moxidectin. Moxidectin 2mg/ml placed in the drinking water at the rate of 5ml/L kills round and hair worms as well as feather mites. Individual birds can be given ¼ /ml direct to the beak. Moxidectin does not kill lice, however, if taken orally (because unlike mites that feed off blood, lice live off feather debris and dandruff). Alternatively to kill all external parasites moxidectin can be placed in a bath at 1/10 the oral dose ie ½ ml /L . This method is safe, easy and effective. Permethrin sprays are also useful to eradicate external parasites. These are purchased as a concentrate, diluted down into a spray bottle and are then ideal to spray new birds prior to introduction to the loft.
Correct timing of PMV, Rota , Salmonella and pigeon pox vaccinations. The two constraining parameters for pigeon pox vaccination are the date racing starts and the age of the birds. Race programs in all Australian states are different. Pigeons should not be vaccinated closer than six weeks to the start of racing, as usually scabs are carried for –four to six weeks post-vaccination. Birds carrying these scabs are infectious and therefore ineligible for competition. Vaccination protocols were discussed extensively last month.
. Beware the overuse of drugs, which can interfere with the ongoing natural exposure of the developing pigeon to potentially infectious organisms. Incorrect use of drugs at this time may in fact render the team more vulnerable to disease.
Establishing a routine that is familiar to the young bird. Pigeons gain a lot of security from a familiar environment and predictable routine.
By doing what they can to minimise stress fanciers can dramatically decrease the chance of disease in young recently weaned pigeons. If disease does occur it is important that it is managed correctly. Fanciers with queries are welcome to call either the Australian Pigeon Company on 0450 400 034 or me directly on 0412 481 239.
At this time of year (February and March) many lofts will be experiencing respiratory infection in some of their young birds. This usually presents as a few birds with one eye becoming red and watery.
Respiratory diseases are common in pigeons. They are a major cause of poor performance and pigeon loss during the race season. Young birds under stress are most at risk of developing respiratory diseases, although healthy old birds can fall ill when exposed to respiratory diseases in the race basket. For birds to give of their best it is vital that fanciers have an understanding of respiratory infection and how to correctly manage it.
Nature of the disease
Clinical respiratory infection in pigeons is the end result of the interplay of a number of factors, but the type of infective organisms involved and the vulnerability of the birds to infection are particularly important.
The usual organisms involved are Mycoplasma, Chlamydia and a range of bacteria (most commonly, E. coli). Whether or not these organisms actually cause disease in a pigeon, if it is exposed, essentially depends on how well the pigeon is at the time of exposure and also its age and level of immunity. Any factors that cause physiological stress can weaken the bird and make it more vulnerable to developing a respiratory infection. As a general rule, younger pigeons are more susceptible. However, in a bird that is otherwise healthy exposure to the agents that cause respiratory infection does not necessarily make it sick. Exposure to these organisms as the young pigeons grow and develop, rather than cause disease, stimulates immunity to form in a bird that is otherwise healthy.
Predisposing stress factors that can make pigeons more vulnerable to respiratory infection can take the form of:
1. Environmental triggers; e.g. dampness, overcrowding, low hygiene
2. Management triggers; e.g. poor feeding, excessive tossing, or
3. Concurrent disease, in particular parasitism. This includes wet canker. The combination of either worms or elevated trichomonad levels and respiratory disease is very common.
The fancier must establish a healthy loft environment; otherwise respiratory disease will continually recur, despite medication. A good example here is a fancier who was recently in our clinic. He had a group of young birds that had dropped about three flights; that is, were about ten weeks old. A few kept getting ‘eye colds’. He would treat them and they would become well but within two weeks there would be more birds with the same problem. In a 2m x 2m section, he had 40 youngsters, and the humidity reading (from a hygrometer placed on the wall of the loft overnight) was 85%. Reducing the number of birds to 25 per section, and installing an additional vent high on the back wall improved ventilation and reduced humidity. The birds were again treated, but this time the problem did not return.
This article discusses respiratory infection associated with Chlamydia.
Chlamydia are one of the 2 common organisms that cause respiratory infections in pigeons. Chlamydia are an unusual group of organisms. They are what are called intracellular bacteria , ie they actually live inside the tissues of animals. Being bacteria they are antibiotic responsive. As a group, they can cause disease in a variety of animals. One species causes disease in koalas while another causes a venereal disease in humans. The species that infects pigeons is called Chlamydia psittaci. It essentially has two lifecycle stages – a reticulate body and an elementary body. The elementary body can survive in the environment. Pigeons become infected through contact with the elementary body. The elementary body typically attaches itself to the superficial lining cells of the eyelid, throat or upper respiratory tract. The elementary body then penetrates the cell membrane into the cell and becomes a reticulate body. The reticulate body then replicates itself until there are many reticulate bodies in the cell. As the reticulate bodies increase in number, they rupture into adjacent cells causing cell destruction and an advancing wall of inflammation. Alternatively, they rupture back out on to the surface of the cell, once again becoming elementary bodies and further contaminating the environment. Infected birds with active disease shed large numbers of these infective elementary bodies in their saliva, tears, respiratory discharges and droppings contaminating the loft. Poor loft hygiene enables a build-up of the organism in the loft. Combine this with birds that are a bit run-down and a disease outbreak occurs. However in well managed lofts disease is rare. In fact ,as mentioned above, it is thought that low grade exposure to these Chlamydia elementary bodies may not cause disease but, rather, trigger the development of an immune response in a pigeon that enables it to be more resistant to the disease. The typical situation in most racing lofts is that Chlamydia tends to cycle through the birds. Growing youngsters are passively exposed to the organism from other birds in the loft and their parents. Often this doesn’t cause disease. Most birds, by the time they are six months old, have had multiple low grade exposures and have developed a significant immunity. Disease occurs if the youngsters become ‘run down’ due to stress factors and are therefore unable to mount an immune response or, alternatively, their level of immunity is challenged by a particularly high exposure to the organism. An antibiotic called doxycycline is very effective at treating Chlamydia. If a pigeon is given a 45-day course it has a 98% chance of clearing Chlamydia totally from its system. One would think that it would make sense to treat all the birds for 45 days, eradicating the disease and then not worry about it in the future. The difficulty with this is that if we were to eradicate Chlamydia, it is known that any immunity that the pigeons have would gradually disappear. This would mean that if the birds were subsequently re-exposed, they would be a very vulnerable population and potentially severe disease could occur. Once racing starts, exposure to Chlamydia in the race units is virtually guaranteed. Although drugs can be used to treat Chlamydia again and again if it keeps reappearing in returning race birds this is obviously not desirable. The factor that principally protects the birds in the race unit is the immunity that they are able to form if they are well cared for in the loft while young and maturing . Chlamydia is therefore managed by caring for the birds well ( so that they can mount a good immune response), by allowing a controlled exposure to the disease ( to build up a strong immunity) through the maintenance of loft hygiene and by using medication if required during development in a way that keeps the birds healthy but still allows some exposure to the disease. How is this done?
In the post-weaning time Chlamydia cycles through the developing young birds. Some youngsters may have passive immunity acquired through the egg and from their parents in the crop milk. Further exposure in the young bird loft builds on this immunity. Some youngsters take longer to form a protective immunity than others, and these can show symptoms of clinical Chlamydia infection. If the birds are well otherwise, these symptoms are often described as a “one eye cold”. Symptoms are often mild and may include a dirty cere, sneezing, nasal discharge, a partially closed light sensitive eye, inflamed red eyelids, and also tears overflowing the eyelids and becoming air dried on the feathers around the eye. If the number of birds affected is low and the symptoms are mild, often no treatment is provided. With ongoing good care it is likely that the birds will fix themselves and will develop a stronger natural immunity this way. If the symptoms in an individual bird become more severe, particularly if the bird’s development is starting to be compromised, treatment should be provided. The usual treatment is doxycycline 10–25mg per pigeon once daily. If less than 5–10% of birds are affected, it is best to just treat these birds individually. There is no need to separate them from the rest as all birds are likely to have the organism in them. Also young birds tend to recover better if left with the flock in a familiar loft. If more than 10% of birds develop symptoms then a flock treatment should be given. The usual treatment is doxycycline in the water. However, if 10% or more are developing symptoms, this tells you that this group of young pigeons is having trouble developing their natural immunity. And if they are having trouble developing a natural immunity this means that something is stressing them. A review of their management, loft environment and a check for any other (particularly Circo virus and parasitic) disease should be done. In young birds the underlying stress is often overcrowding. In Victoria, Australia, January to May are the respiratory months. Most lofts contain large numbers of young birds having just had the stress of weaning and now having the stress of moulting, coupled with young bird training and establishing themselves in the loft. It is a time of high humidity and fluctuating temperature, conditions that favour respiratory disease. Between 1 December and 1 March (the usual time that the last youngsters are weaned in many lofts in Australia), fanciers must monitor the youngsters, in particular for signs of “one-eye cold”, dirty wattles or sneezing. However, green watery droppings, failure to thrive, shortness of breath and a reluctance to fly may also be indicative of the problem. After 1 March in Australia, as the youngsters get older, fanciers look for signs of poor loft flying, excessive panting after training, and sneezing within the loft. Even in the healthiest lofts, there can be occasional outbreaks of respiratory diseases. It is important to recognise that more than three sneezes within five minutes from 100 birds is a significant indicator of early respiratory disease. One would expect two to three sneezing outbreaks between January and May, even in the best managed loft.
As racing approaches, the birds have been given as long as possible to develop their natural immunity. It is important, however, that there is no active Chlamydial respiratory infection in the birds when racing starts. The can lead to poor race results and potentially disastrous returns. Chlamydia tests can be done by your veterinarian to see if the disease is still active and if the birds have formed a good immunity. The usual tests available are the Chlamydia immunocomb test, or Chlamydia PCR test.
A team should only be treated for Chlamydial respiratory infection before racing if it fits into one of the following categories:
1. If testing shows that the disease is still active in the birds, even if they look normal.
2. If Chlamydial respiratory infection was a problem during the early part of the racing season the previous year and the loft parameters have not changed (i.e. same loft design, same genetics, etc.)
3. If there was a significant amount of respiratory disease in the post-weaning time.
4. If the birds have a current clinical respiratory infection.
If the loft fits into one of the above categories then it is usual to treat the birds for 7–20 days with doxycycline, finishing two to three weeks before racing starts. Just how long an individual team is treated depends on the severity of the problem and the response to treatment. If they do not fulfil one of these criteria then no treatment is required.
I have had several fanciers tell me that they have been advised by a vet that the best thing to do prior to racing is treat their birds regardless with doxycycline. They were told that if it makes their birds sick then they don’t need it. If it does not make them sick then they must have Chlamydia and a long course of the drug should be given. I find this advice hard to believe as coming from a vet . It would see potentially tens of thousands of pigeons given antibiotics they don’t need in an absolute bogus way of assessing Chlamydia status. Such a suggestion is nonsense.
Management during racing
Ongoing exposure to Chlamydia occurs during the racing season. The natural immunity the birds have formed through development should be high enough to protect them; however, because of the stress associated with racing and potentially high exposure to the organism it may not be. Fanciers should monitor their birds closely for symptoms and have their birds regularly checked by an avian vet. If the birds become unwell or race performance is compromised due to Chlamydia, then the team is treated as a single unit and a flock treatment of doxycycline is given. Birds return to health fairly quickly, but not to race form. Sometimes a race needs to be missed and then the level of work gradually increased as the birds regain their health and fitness. If Chlamydia is diagnosed through the racing season, what should the fancier do?
1. Conduct a health profile– i.e. examination of the saliva and droppings and sometimes other tests as suggested by your veterinarian to assess any concurrent disease that may need treatment. Provide general ongoing good care to ensure a good response to medication.
2. Return to exercise gradually. Always, with respiratory infection, there is an extended convalescence usually of 1–3 weeks. The birds must be given time to recover their fitness once medication has cleared the infection. They should not be forced to fly around the loft and once it is apparent that their vigour for flying has returned, short tosses only should be given (less than ½ - 1 hour) initially. Observe the birds closely for signs of breathlessness on landing from these tosses and only when they are handling these well should longer tosses be given. When managing tosses of 1–1½ hours well, it is usually safe to resume racing. In well-managed lofts with no other health problems, response to treatment can, however, be dramatic and I have had an interesting experience where two fliers both diagnosed with respiratory infection in their teams succeeded in gaining 1st and 2nd Federation (3000 birds) in an all-day 800km race 3 weeks after treatment.
3. Give good food, good care and an appropriate multivitamin supplement to speed recovery.
4. Give appropriate medication. The choice of drug is often dependent on the involvement of secondary organisms, but usually the antibiotics doxycycline and tylosin are given together, or a blend of doxycycline, tylosin and spiramycin. An initial course usually of 3–10 days is given, depending on the severity of the infection and response to treatment.
Symptoms of Chlamydial Respiratory Infection
In young birds, symptoms are usually confined to the upper respiratory tract and the most common signs observed are a dirty cere, nasal discharge and a red watery eye. In some birds, however, the organism can infect various internal organs including the liver and spleen and also deeper parts of the respiratory tract, particularly the air sacs. These birds may just be quiet, be reluctant to fly, lose weight and develop a green mucoid dropping. Birds with inflamed air sacs often become breathless after moderate exercise and are sometimes forced to land wherever they are. This may include buildings or trees near the loft. By the start of racing the birds are older, their natural immunity is higher and their response to disease is different. The signs observed are modified by these factors and are often very subtle. Older birds with respiratory infection have lost their zest for life, and this is reflected in their race results. Birds that are reluctant to fly, quiet in the loft and with dry feathers (no bloom) are suggestive of respiratory infection. Irritation to the upper airway usually shows itself as an increased rate of sneezing. Sneezing (more than three times in five minutes from 100 birds), scratching at the nose, yawning, repeated exaggerated swallowing, stretching the neck and wiping the nose on the wing butt all indicate irritation of the upper airways. On opening the beak, inflamed tonsils may be seen, a thick white mucus may be extending into the throat from the windpipe or from the ‘slot ‘in the roof of the mouth, which may be closed due to swollen edges, the top of the windpipe may be red and inflamed, the beak at the nostril opening may be wet, the cere may be slightly discoloured or there may be a slightly mucous component to the birds’ grunt. The lining of the throat or the muscles may be bluish. Chronically-infected birds show delayed recovery after a race and will develop green droppings after stress because of damage to the liver. Sometimes the only symptoms in race birds, however, are poor performance and increased losses. Birds with inflamed sinuses tend to cope particularly poorly on cold head-wind days. Presumably the cold winds buffeting the already inflamed sensitive sinuses across the face act a bit like an ‘ice cream freeze’ making the going hard. Chlamydia can be carried throughout the body in the bloodstream and in birds of any age severe systemic disease can occur. Here birds become severely unwell and, without prompt correct treatment, some will die. In some birds the gonads will be damaged. This can lead to decreased fertility in both cocks and hens. Hens with a Chlamydial infection of the ovary often have late or irregular ovulations or no ovulations at all. If an egg is produced, sometimes Chlamydia can be incorporated in the egg, where it can either kill the developing embryo or lead to the hatching of a weakened chick.
It is important not to confuse symptoms with a diagnosis. Many pigeon diseases have similar symptoms. The symptoms described earlier are all suggestive of the problem, but an accurate diagnosis can only be reached through testing. The tests used today provide a speed and accuracy not available to vets or fanciers in the past. The tests in common use are:
1. The Chlamydia Immunocomb test – a serology test, and therefore can only be done on whole blood. A drop of blood is collected. The veterinary technician then follows a series of steps. The test detects the presence of a particular immunoglobulin, IgG, in the blood, formed in response to Chlamydia exposure. Results are available in 4 hours.
2. Chlamydia PCR test – detects the presence of Chlamydial DNA. PCR tests are available for Chlamydia and also Mycoplasma. The test is usually done on a swab collected from the throat, slot and eye. Results are usually available in 2–4 days. A very accurate test.
Worldwide the medication of choice for Chlamydia is doxycycline ( for example, Doxyvet™). Some other antibiotics do have an affect against Chlamydia, notably enrofloxacin (Baytril™) but are not as effective as doxycycline. Baytril™ stops Chlamydia replicating, but fails to clear it from the pigeon’s system. It therefore reduces clinical symptoms and treated birds appear to get better, but relapses are common. Doxycycline actually stops the organism replicating and clears it from the pigeon’s system. In preparations made for racing pigeons, doxycycline is often combined with tylosin (commonly used to treat Mycoplasma); for example, Doxy-T™, and sometimes also spiramycin (also called suanovil); for example, Triple Vet™, that treats many of the bacteria involved with respiratory infection. These combinations aim at providing a broader respiratory treatment targeting all of the likely organisms involved. Doxycycline absorption from the bowel is compromised by concurrent use of calcium-based supplements and so it is best to remove grit, pink minerals and picking stones during treatment. Also, doxycycline is absorbed slightly better from the bowel in a weakly acidic environment. Adding citric acid (3g/6L water) during doxycycline administration is recommended by some vets. Drinkers made from non-glazed pottery or galvanised metal can also adversely affect doxycycline action. Drinkers should also be kept out of direct sunlight as UV light and heat can inactivate the antibiotic. Contamination with organic material such as droppings can also denature the doxycycline.
Fanciers with any queries are welcome to contact The Australian Pigeon Company on 0450 4000 34 or me directly on 0412 481 239
Vaccination is the key to preventing some of the most serious pigeon diseases.
Pigeons are vaccinated to protect against some of the common serious infectious diseases. Vaccination stimulates the body’s defense system to build immunity to a particular disease, by exposing pigeons to either the live organism presented in a safe form (eg Pigeon Pox vaccine) or to a killed organism (eg PMV vaccine), or an inactivated organism (eg Salmonella vaccine) or part of an organism (eg Rota virus vaccine).
What vaccines are available?
1/ Paramyxovirus ( PMV ) vaccine . Two brands are available , Poulvac ( Zoetis ) or Newcavac (MSD) . Both are made from a killed La Sota PMV virus originally isolated from chickens.
There have been several issues raised by fanciers over the last 7 years since these vaccines were first used :-
a/ “but it is a chook vaccine” – it makes no difference what species of animal a particular virus was originally isolated from. The most important thing is the degree of antigenic overlap ie how similar two viruses are to each other . If two viruses are very similar then it more likely that the immune response elicited by the pigeon to one is likely to protect it against both viruses. Horses are actually immunized against Hendra virus using a canary pox vaccine!
b/ “I want to use the NDV4 live PMV vaccine”-- in the vaccine trials we conducted in 2012 this vaccine did not stimulate the same amount of immunity as the killed La Sota vaccines.
c/ Can the live NDV4 vaccine give my pigeons the disease--the NDV4 vaccine , even though it is alive, cannot give the pigeons PMV. It has been modified and is harmless.
d/ “I want to use the PMV vaccine used in Europe made from a PMV strain isolated in pigeons” – when pigeons are vaccinated with the killed La Sota vaccine they form enough immunity to stop them getting sick but not enough to stop them getting infected with the virus. Vaccinated birds can carry the virus “ silently” for up to 60 days. The only advantage of the European pigeon origin PMV vaccine is that these silent infections are less likely to occur and when they do occur last for a shorter time. This makes no difference if all of the pigeons are vaccinated. And of course, it is illegal to import all avian vaccines into Australia. Fanciers who do so risk prosecution.
2/ Pigeon Pox vaccine
3/ Paratyphoid ( Salmonella vaccine ). Two pharmaceutical companies in Australia , Bioproperties and Treidlia both make Salmonella vaccines. I only have experience with the Bioproperties vaccine. I am sure that the Treidlia vaccine is effective and fanciers may wish to use this brand instead.
4/ Rota virus vaccine – Rotavax made by Treidlia.
Timing of Vaccination is Crucial
With most vaccines , but not all, it is usual to give two vaccinations. When two vaccinations are necessary timing is crucial. The first dose sensitizes the immune system and the second dose starts antibody production. Without the second booster dose, the initial vaccination only protects the pigeon for a short period of time, probably just weeks. The booster vaccination prolongs the protection period so that the pigeon is covered for about 12 months. An annual booster is then required to provide cover for a further 12 months.
THE SENSITIZING DOSE - Sensitizes the immune system
- Initiates antibody production, takes several weeks
- Protection provided is short lived, weeks to months
THE SECOND VACCINATION - Increases immunity to protective level
- Provides cover for 12 months
- Cover is less protective as time passes since vaccination
THE ANNUAL BOOSTER - Stimulates the immune system
- Provides cover for a further 12 months
This process is illustrated in the chart below. The vertical axis shows the level of immunity formed while the horizontal axis shows time in weeks. As can be seen , the first or sensitizing dose only stimulates a low and short term level of immunity. Timing of the second dose is crucial
Chart used – courtesy of PIRSA
How to use the Vaccines
1/ Salmonella ( Bioproperties)
Preparing the vaccine:
The vaccine comes in a 1000 dose vial. This needs to be kept frozen until use. The vaccine is dissolved into 100mls of water for injection. This is done by repeatedly rinsing the vial with sterile water (available through your vet ) using a needle and syringe until all of the vaccine is dissolved in the 100ml bottle of sterile water. The vaccine mixture must be used within 2 hours of preparation. Each pigeon is given 0.1ml of this mixture.
How to give the vaccine:
The vaccine can be given in 1 of 3 ways:
0.1ml injection under the skin at the back of the neck
0.1ml of vaccine can be given orally. The vaccine is equally well absorbed from the lining of the bowel as from an injection under the skin. Using this method it requires very little effort to protect your birds.
The vaccine can be added to the drinking water at the rate of 10mls in 5 litres of water to vaccinate 100 pigeons. All of this water must be drunk within 2 hours for the vaccine to be effective. Because this is difficult to achieve this is regarded as a less optimal method.
Two doses of vaccine are given 2-4 weeks apart. The vaccine is cheap – about $110 for 1000 doses
2/ PMV vaccine
2 doses of 0.5 ml ,4 weeks apart under the skin at the base of the neck after 6 weeks of age. Annual boosters are necessary
In high risk situations a first shot can be given at weaning ie 4 weeks but as each pigeon needs 2 shots after 6 weeks of age this will necessitate giving 3 shots ( which is fine )
Other issues to consider
a/cheesy lumps can occur at the vaccination site. These are due to infection. If a fancier is getting more than 1% of vaccinated birds with these he should reconsider his technique which may involve using a new needle every few birds
b/ damage to the immune system – information has been circulated that the use of oil based vaccines ,such as PMV, damages the immune system in young pigeons and can cause reduced fertility in breeders. After a review of the veterinary literature, raising the issue in a chatroom of international experts, speaking to the vaccine manufacturer and also the appropriate Australian regulatory body there is just no evidence of this happening. Fanciers can use the vaccine with confidence that they are not damaging their birds
c/passive immunity from parents – when breeding from vaccinated birds some of the breeders immunity can pass to their youngsters. This immunity that is acquired “passively” by the youngsters from their parents can interfere with them forming their own “active” immunity when they are , in turn, vaccinated. This “passive” immunity is all gone by 6 weeks of age. What this means is that the immunity formed by a youngster, bred from vaccinated parents, that is vaccinated under 6 weeks cannot be reliably predicted to protect that youngster. To be sure that the bird is immune it must receive 2 shots after 6 weeks of age. Fanciers can expect to pay about $200 for a 1000 dose bottle in Melbourne.
3/ Pigeon Pox
A prick or scratch on the outside of the thigh is given after 6 weeks of age . Single vaccination confers life time immunity. A vial that potentially does 500 birds is about $90.
4/ Rota virus vaccine – We still have much to learn. A trial at Melbourne University in the new year will, hopefully , provide more answers. The current recommendation is that 2 vaccinations of 0.5 ml are given under the skin at the back of the neck 4 weeks apart. A 300ml bottle costs about $450
Pulling it all together.
1/After 6 weeks of age --- Give a 0.5 ml injection for PMV and separate 0.5ml injection for Rota under the skin of the neck; 0.1 ml Salmonella given orally (Bioproperties vaccine) .
2/ Four weeks later, same again, ie injection for PMV and separate injection for Rota; also 0.1 ml Salmonella given orally (Bioproperties vaccine) but in addition Pigeon Pox scratch on thigh.
How to Breed 100 Youngsters from One Cock in a Year
This year I was fortunate enough to live overseas for 2 ½ months . During this time I was lucky enough to spend time with Dr Pascal Lanneau at his veterinary clinic in Kortemark, Belgium. The clinic is very busy with many pigeon racers bringing their birds in for various veterinary procedures throughout the day. Amongst other things Pascal does genetic testing of birds to guarantee parentage, genetic profiling to see if birds are carrying genes that have been linked to high performance and also semen collection and artificial insemination (AI). Using AI many, many youngsters can be obtained from a single cock in one season. This is how this is done. Vasectomies are done on cocks of low racing value. In this technique, under general anaesthesia an incision is made between the vent and the pubic bone to enter the abdomen. Through this incision, the ureters ( which carry urine from the kidneys to the cloaca) and the vas deferens ( which carry sperm from the testes to the cloaca ) can be seen. The vas deferens is ligated and a section removed. This effectively sterilises the cock. Usually cocks of unusual colours such as reds and grizzles are chosen so that if the vas deferens reconnects this will become apparent. These sterile “teaser” cocks are then mated to good hens. These hens will then predictably lay about 10 days after mating. From day 6 the good cock is artificially ejaculated through a massage technique. The collected semen is diluted with an extender fluid and placed into a micro pipette. The good hen ( mated to the teaser) is placed into a specially designed cradle, an instrument is used to dilate her vent and a dose of semen is placed directly into her lower oviduct. This is done every day or every second day until she has laid her 2 eggs. After insemination she is placed back with her teaser boyfriend and the “mated” pair then raise the babies as their own being able to feed crop milk at the required stage. A single ejaculation can service 10 hens. This may sound complex but Pascal made it look easy and in this way many youngsters can be produced off one cock in a very short period. In one instance a very valuable cock was sold to China. In the 2 weeks before he was shipped, 10 hens were inseminated resulting in him leaving 18 youngsters (and 2 clear eggs ) behind when he left just 2 weeks later
Last year in Melbourne, of the fanciers that used Rotavax, virtually 100% reported that despite using the Rota virus vaccine that their birds actually caught the disease when they were subsequently exposed to the virus. The proportion of birds in each loft that became unwell varied from about 5 to 35 % . Fanciers reported that although some of their birds became unwell , the symptoms were milder and of shorter duration than they had experienced in earlier years and that there were very few deaths. The suggestion was that the vaccine had stimulated sufficient immunity to significantly modify the severity of the disease but not enough to prevent all birds from becoming sick. What concerns me is that in Melbourne there were some lofts that did not vaccinate but experienced a similar pattern of disease. Some fanciers have therefore asked, and quite rightly so, did the vaccine actually do anything. Frustratingly for many fanciers their birds became unwell right at the start of racing when they started mixing with birds from other lofts for the first time. For some this meant actually missing the races for which they had prepared the birds or alternatively risking losing birds by sending them to races prematurely while they were still convalescing from the disease. With this year’s breeding season now in full swing fanciers need to know how best to manage Rota virus during 2020
No immune testing has been done on the vaccine made by Treidlia so basically we just don’t know what level of immunity is formed. I recently contacted Dr Mark White. Mark has always been very helpful and of course we would not have the vaccine without him but he advised that everyone at Treidlia is very busy at the moment on other projects and investigating the level of immunity formed by the vaccine is not a top priority. He did however offer to help with the bulk testing of samples.
It bothers me that we don’t know how effective the vaccine is. I am keen to demonstrate just what level of immunity the Rotavax does stimulate. Hopefully it is quite high. To this end I intend running a fairly basic immunity trial this year on my own birds. After spending several months overseas this year I am now back in Australia and getting ready to resume racing next year. My birds have essentially been isolated since November 2018. I will breed about 200 youngsters this season ie before the start of February .The breeders all had Rota virus in 2018. I will bleed about 10 of the youngsters at weaning ( 4 weeks ) to ensure they do not already have some immunity, Rotavac them at 6 weeks and then bleed them every 2 weeks for a couple of months. After several months they will be bled monthly. They will have a second Rotavac 4 weeks after the first. In this way it should be possible to develop an immunity curve. One problem is that an accurate commercial test has not as yet been developed . I have however contacted Agribio and other labs about this. Another problem, as advised by Mark, is the fact that systemic antibodies in the blood don’t really measure gut immunity. It is possible to do ELISAs ( an immune test ) on gut secretions to measure IgA ( a type of antibody ), but is more complicated than blood testing and usually requires sacrificing some birds at each time point for testing. Obviously I don’t want to kill any of my young birds. Discussions are continuing. I intend to do all of the veterinary work myself and also cover the cost of the laboratory testing. I will release results on my website and in this magazine as they become available
New Vaccine for Salmonella
A very effective vaccine against Salmonella has been available for several years now and yet some fanciers are still unfamiliar with it. The vaccine has been fully trialled and has been shown to produce high levels of immunity that are fully protective against the disease. Salmonella is an important disease to control during racing. Salmonella is commonly carried in the bowels of healthy pigeons. Exposure in race units is common. When pigeons get stressed and their ability to fight infection is reduced Salmonella can invade the body through the bowel wall and cause disease. Salmonella is one of the many health problems that can flare in the race season when the birds come under stress. Salmonella flare-ups during racing cause a loss of form, require lengthy antibiotic coarses to control and have a prolonged recovery period. They can also be difficult to diagnose and for this reason are often diagnosed incorrectly. Vaccination before racing is a very effective way of decreasing the chance of this happening.
Preparing the vaccine:
The vaccine comes in a 1000 dose vial. This needs to be kept frozen until use. The vaccine is dissolved into 100mls of water for injection. This is done by repeatedly rinsing the vial with sterile water (available through your vet ) using a needle and syringe until all of the vaccine is dissolved in the 100ml bottle of sterile water. The vaccine mixture must be used within 2 hours of preparation. Each pigeon is given 0.1ml of this mixture.
How to give the vaccine:
The vaccine can be given in 1 of 3 ways:
Interested fanciers can get further information by contacting the the Australian Pigeon Company or visiting the APC website . Just google Australian Pigeon Company and look in the Bacterial Diseases – Salmonella section.
Pigeons don’t get Salmonella from rodents
Up until recent years, standard knowledge throughout the veterinary and pigeon community was that paratyphoid in pigeons was caused by the bacterium Salmonella typhimurium. This species of Salmonella was regarded as a wide-spread organism in nature.
It was thought that the variety that infected pigeons also infected many other animals, particularly rodents. After all, the organism’s name “typhimurium” literally means typhoid of mice. It is now thought that this is unlikely. We still have a lot to learn, but our understanding of Salmonella infection in pigeons has changed over the past few years. Today’s technology enables us to type various strains of Salmonella very specifically.
The Salmonella strains that can cause clinical disease in pigeons can be identified right down to the phage type. It is thought that these phage types are likely to only cause disease in pigeons. This means that Salmonella strains found in other animals such as wild birds, chickens and other mammals including rodents don’t cause disease in pigeons.
It seems likely that Salmonella in pigeons is a pigeon to pigeon disease with the source of infection being asymptomatic carrier birds or their droppings. Non- infected birds can be exposed to asymptomatic carriers in the race basket or in the home loft if carriers are introduced by the fancier.
The actual type of Salmonella that infects pigeons has been identified as Salmonella enterica, subsp. enterica, serovar typhimurium, variant copenhagen, Anderson phage types DT2 and DT99. In one study, 10,000 cases of pigeons infected with Salmonella were investigated. All except 3 were infected with these phage types. It is possible to identify other species of Salmonella in pigeon droppings but these are regarded as transients that have been accidently ingested and not capable of causing disease.
New fertility drug available
Medications are now available to stimulate fertility in both old cocks and hens. A small gland at the base of the brain, called the pituitary, produces, amongst other things, a hormone called gonadotrophin. This stimulates ovulation (which leads to egg laying) in hens and sperm production in cocks. In birds, the pituitary produces this hormone primarily in response to increasing daylength but also increasing environmental temperature, which is one of the reasons why birds start to breed in Spring. This also explains why fertility is often higher in the second round than in the first.With age, gonadotrophin production falls.
The use of a slow release gonadotrophin releasing hormone (GNRH) called Buserelin acetate has been shown to induce significant increase in testosterone concentration in male birds and an increase in egg production in hens. The drug works best in older cocks, which may have filled all eggs 3 years ago, perhaps four of six 2 years ago, and only one last year. These birds usually still have some testicular tissue capable of responding to gonadotrophins.
The longer birds have been sterile, the less likely they are to respond, and birds that have primary disease of the gonads, e.g. testicular cancer or an ovarian cyst, cannot respond. Two injections are given two weeks apart. These are best given at the beginning of Spring so that they can act together with the birds’ naturally produced gonadotrophin. Hens having injections are best left with their cock so that he is there to fill any eggs, if and when ovulation occurs. However, cocks are usually best kept away from the hens while having these injections because, being a sex hormone, the injections tend to give the cocks a high libido, leading to repeated mating and sometimes wasted poor-quality ejaculates.
It is usually best to put treated cocks with their hen after 3 - 4 weeks. The medication can take up to 6 weeks to work.
Recent work at the University of Melbourne has shed light on the roll of a gland in the crop wall of pigeons that helps supply the newly hatched chick with immunity straight from it’s parents. This gland is called the Teichman gland. When the crop enlarges to produce crop milk, this gland also enlarges. The gland produces immune cells and it is thought that these immune cells move from the Teichman gland into the crop milk, in the process giving freshly hatched chicks some passive immunity directly from their parents. What stimulates the gland is unclear but suggestions have included the altered hormone status that occurs when pigeons produce crop milk or the chick itself moving in the egg as it starts to hatch.
Changes at the Melbourne Bird Veterinary Clinic
After 40 years of practising as a veterinarian I decided to sell the Melbourne Bird Veterinary Clinic in August this year. Spending less time at the clinic means that I now have more time to focus on other pigeon related activities. The Melbourne Bird Veterinary Clinic"s commitment and passion to pigeon racing continues.The practice has been purchased by Dr Pat Macwhirter and Dr Matt Gosbell. Working with them are Dr Lee Peacock and Dr Madeline Rowe. Pat is not only an avian vet but one of only 6 registered avian specialists in Australia having achieved her fellowship in avian medicine. Pat also has a PhD. Matt is lecturer in Avian medicine at The University of Melbourne and is a qualified avian vet with 15 years experience operating the Springvale Veterinary Hospital. Lee is also a qualified avian vet and also works at the Healesville sanctuary while completing her PhD. Madeleine graduated as a vet in 2017 from the University of Melbourne and is studying to become an avian vet .The Melbourne Bird Veterinary Clinic is one of only two "bird only" veterinary practises in Australia (the other is in Brisbane) and the only clinic in Victoria and New South Wales with three avian vets on staff. Services to our pigeon clients remain unaltered. Pat, Matt and Lee have many years experience working with birds generally and, although still building their experience with the various facets of racing itself, are totally familiar with pigeon disease, diagnostics and medicine. Pigeon products can be obtained through the Melbourne Bird Veterinary Clinic ( 03 9764 9000) or directly from the Australian Pigeon Company ( 0450 400 034) .Fanciers who wish to speak to me can always reach me through the Australian Pigeon Company. I look forward to helping fanciers whenever I can.
It is important that fanciers use antibiotics correctly. Many antibiotic preparations used by fanciers are blends of antibiotics. For example, "Sulpha AVS" contains trimethoprim and sulphadiazine, while "Doxy T" contains doxycycline and tylosin and "Triple Vet" contains doxycycline, tylosin and spiramycin. I know of some fanciers who give Sulpha AVS and Triple Vet each one day per week to the birds. This means they are giving five different antibiotics for one day a week to their birds. This achieves nothing and the potential for the development of harmful organisms and subsequent disease is enormous. Such fanciers run the potential of getting into a spiral of using more and more drugs to control routine problems . It sounds harsh but the only one who probably benefits in this situation is the supplier of the drugs.
Length of Antibiotic Treatments
Too many fanciers use antibiotics for too short a period of time to be effective. Antibiotic courses of three days should be the minimum. Antibiotic courses of five to seven days are routine. Sometimes longer courses are required. Giving shorter courses of antibiotics kills the easier to kill bacteria and selects for a population that is harder and harder to kill. Some antibiotic medications, particularly those used for respiratory infections, are used by fanciers as outlined above are blends of two or three different antibiotics. This compounds the situation. Giving multiple antibiotics together for short periods is a great way of creating "super bugs" in the loft that become progressively harder and harder to control.
Over the last year many fanciers, sometimes as many as three or four per day, have rung the Melbourne Bird Veterinary Clinic saying their birds have been diagnosed with health problems due to the bacteria Streptococcus. In one instance a whole club was diagnosed with Streptococcus. Ill health and poor race performance due to Streptococcus in pigeons cannot be diagnosed by examining droppings and certainly not over the phone. Streptococcus is a normal inhabitant of the pigeon"s bowel. It is found in 40% of healthy pigeons" droppings (even Fed winners). Streptococcus can invade the bowel wall and cause disease in other sites of the body, as indeed can many other bacteria in a pigeon’s bowel (as can bacteria in our own bowel for that matter). Finding Streptococcus in the bowel of healthy pigeons means nothing and treating it there is not only a waste of time and money but opens the door for other health problems. Put simply, demonstrating the presence of Streptococcus in the droppings means nothing. They are normal there. Saying that this is a problem, in my opinion, demonstrates a failure to understand the condition and suggesting treatment is simply a waste of time and money.
The same can be said of identifying Streptococcus ( and for that matter Staphylococcus) in the throat of pigeons. Although these organisms can cause disease they are often found in the throat of perfectly healthy pigeons. Simply demonstrating their presence on a swab taken from the throat does not mean they are causing a health problem. Very non- specific symptoms such as “not wanting to fly’ have been attributed to Streptococcus found on a swab of the throat. This bogus diagnosis is sometimes readily accepted by fanciers keen for a diagnosis, even if it is the wrong one. If this problem is diagnosed in your birds without more thorough testing – get a second opinion. A list of qualified avian vets in Australia can be found on the APC website. Google Australian Pigeon Company and click on “About ‘ on the homepage
Diagnosing Airsac Disease in the Droppings
Diagnosing mycoplasmal respiratory infection by examining the droppings is another "untruth" that has become more widely believed throughout the pigeon community over the years. Fanciers often mention this. Professor Bob Doneley, the Professor of Avian Medicine at the University of Queensland, in his book "Avian Medicine and Surgery in Practice", published 2011, specifically states that mycoplasmal respiratory infection cannot be diagnosed in the droppings. To state very clearly, there is no recognised veterinary test that will diagnose mycoplasmal respiratory infection in the droppings. Fanciers should speak to an avian vet about the methods available to accurately diagnose this problem in their birds and how to manage it. Most commonly these days, although symptoms can be suggestive, a mycoplasmal infection is definatively diagnosed by taking a swab and doing a mycoplasmal PCR (ie DNA ) test combined with histopathology ( microscopic examination of tissues),
Not all antibiotics can be given together. Antibiotics fall into two basic categories- bacteriostatic and bacteriocidal. Bacteriocidal antibiotics kill bacteria when they are reproducing. Bacteriostatic antibiotics stop bacteria reproducing and then because bacteria live only a short period of time, the bacterial populations that fail to replicate die out. Bacteriocidal antibiotics effectiveness can be reduced by up to 90% if they are concurrently used with bacteriostatic antibiotics. This is because bacteriocidal antibiotics require the bacteria to reproduce to kill them, but the bacteriostatic antibiotics actively stop the bacteria reproducing and therefore becoming vulnerable. The most common antibiotic blend used by fanciers that fits into this category is a blend of amoxicillin (bacteriocidal) and tylosin (bacteriostatic). Presumably any vet who prescribes this must have good reason to do so.
Baytril and Respiratory Infection
A common cause of respiratory infection in pigeons is Chlamydia. It can cause eye colds, dirty ceres and sneezing etc. Chlamydia often occurs concurrently with other respiratory pathogens like mycoplasma and bacteria. Baytril is not a good choice for a respiratory infection due to Chlamydia. Chlamydia is an intracellular bacteria. Baytril stops Chlamydia replicating but is not particularly effective at clearing the organism from the pigeon"s system. This means that the birds appear to improve but relapses are common. A much better choice of medication is an antibiotic like doxycycline, eg DoxyvetTM that not only stops Chlamydia replicating but also clears it from the bird"s system.
The Supply of Prescription Medications and the Law
Recently in this magazine there was some mention that the laws concerning the supply of prescription medications have recently changed. This is most definitely not the case. It has always been a vet’s duty to responsibly supply prescription drugs. This means ensuring that the animals that the medication is intended for actually need them, will get benefit from them and that the medication will be used in the correct manner. The usual way that a vet meets these requirements and can satisfy any subsequent Vet Board inquiry is by physically examining the birds. Unfortunately some vets feel they meet this requirement by examining any bird from a loft, either with no problem or an unrelated problem, sometimes months earlier and will then supply medication for an extended period without any diagnostic work. Ironically some fanciers feel these vets are providing a good service or in fact are doing them a favour. The end result in many instances is that the fanciers can spend a lot of money and the birds receive a lot of medication that they don"t need. I know of vets in Australia, the US and the UK who abuse their prescribing rights in this way. Such vets are frowned on by the rest of the profession. The only consistent winners in this situation are often the vets selling the drugs. In these days of technology there are many ways to diagnose problems and to develop appropriate health management programmes, even if fanciers are many miles from an avian practice – phone calls, emails, youtube videos, mailed-in samples, couriered-in live or dead birds. With today"s advances in diagnostic technology canker, Chlamydia, Circovirus, Herpes virus, Salmonella, Coccidia , Rota and PMV etc. etc. can all be accurately diagnosed if the correct samples are submitted.
Many fanciers think that there are only two or three avian vets in Australia. In fact there are over 30 fully qualified practising avian vets in Australia. All have achieved this qualification by sitting the same post-graduate exams in avian medicine and surgery and are all equally qualified to help with pigeon problems. Fanciers in the eastern States are spoilt for choice. There are seven or more avian vets practising in each of the eastern states namely Queensland, New South Wales and Victoria. If fanciers are not happy with the advice they receive it can be wise to receive a second opinion. There are only two practices in Australia which exclusively see birds, one is in Brisbane and the other is the Melbourne Bird Veterinary Clinic. Disappointingly for New South Wales fanciers there are no practices that only see birds. In Queensland, New South Wales and Victoria there are several practises that employ more than two avian vets. I think it is best to use a clinic that has several vets on staff. Vets as they age, particularly if they are the only vet in the practice, run the risk of becoming professionally isolated so that their advice may no longer be consistent with the rest of the profession to the point of being no longer fully accurate or even plain wrong.
Cleanse the Bowel
I see products available to fanciers marketed as "bowel cleansers". This is an impossible and silly suggestion. "Bowel cleanser" is an unfortunate term that has crept into the pigeon fancier vernacular. It has as its basis a silly idea that the bowel in an inert tube, like a garden hose and flushing something through will selectively kill the harmful bacteria and in the process "cleanse" the bowel. The bowel, in fact, contains a fragile blend of bacteria that need to be preserved for the bird to be healthy. This blend is easily disrupted by stress and medication. One of the worst things you can do to a racing pigeon is disrupt the normal bowel bacteria. The bacteria found normally in the bowel of a pigeon are essential for digestion and nutrient absorption and help to protect from disease. The "good" beneficial bacteria are the easiest to kill while the potential disease causing ones are harder to kill. Any product marketed as altering or "cleansing" the bowel is almost certainly doing the pigeons harm.
This product is a blend of soaps and detergents marketed by a single vet in Australia. Out of all the vets in the Australia and indeed all the vets in the world only one vet recommends this product. It is a blend of several types of soaps and detergents that the vet mixes together, gives it this name, and markets as a water cleaner and “crop disinfectant”. Some fanciers seem to think that this is a treatment or even a medicine. In fact , its ingredients are toxic if swallowed. Essentially it helps keep birds healthy by simply keeping the water clean! Some fanciers believe that it does everything from "cleansing" the bowel through to curing Circovirus. A belief more due to good marketing than anything that the product actually does. Birds who do well after drinking water with this in it, do well, I believe, despite having had it. It is a nonsense to want to “cleanse” the bowel or crop. The last thing that you want to do is remove the “good” bacteria from these areas and yet these are the easiest to kill. This would mean that even if such products did what they claim ie kill bacteria in these areas,, which is unlikely, they would be harmful. The principal ingredients are used in the manufacture of soaps and shampoos and to help clean swimming pools. They are not meant for internal use and are certainly not medicines or even recognised veterinary treatments . It is not recommended for use in pigeons by any other avian vet in Australia and I personally would never use this product on my own birds.
Some fanciers are quick to jump to "bad food" as being a cause of health problems. Australian fanciers are spoilt for choice by the good quality grains available to them. Australia is typically not associated with poor grains because of our typically dry environment. The experts at the various grain testing labs such as Agrifood who do accurate testing explain that problems in grain due to fungal toxins and bacterial contamination are very very low. Often "bad food" is blamed for poor race performance in the absence of accurate diagnostic work. Simply putting grain onto a fungal growth medium and seeing if it goes mouldy is a totally "bogus" test. Any food, including the good quality nutritious food that humans eat every day will eventually go mouldy if placed in conditions that encourage fungal growth. Labs that do proper testing should give you fungal toxin estimates and spore counts. If a vet or lab cannot provide these figures be suspicious of these results.
Using Drug Courses to Diagnose Disease
It seems incredible that some fanciers do this with Chlamydia. The rationale is that birds are given Doxycycline (the treatment for Chlamydia). If they get better the thought is that they must have Chlamydia, if they get sick the thought is then that they don"t have Chlamydia and don"t need the drug. This system would see all race birds given potentially lengthy courses of potentially harmful and expensive antibiotics before racing that they don"t need . This system is a totally "bogus" method of diagnosis. These days there are a number of cheap ,quick and accurate ways available to your veterinarian of seeing whether it is worth the expense, time and effort and actually beneficial to give the birds doxycycline. Usually race teams are given pre-season courses of Doxycycline only if they fall into one of the following four categories:
1. The birds have an active respiratory infection that is diagnosed as being due to Chlamydia. These days this is usually done by a Chlamydia PCR ( ie DNA ) test done on a swab taken from the throat.
2. The birds look normal but testing shows that Chlamydia infection is active within them. ( Usually biochemistry/ haematology blood test and PCR Chlamydia swab )
3. There were persistent problems with respiratory infection due to Chlamydia in the months between weaning and the start of racing
4. Chlamydia was a problem in the team once racing started the previous year and none of the loft parameters e.g. genetics, loft design, etc. have changed.
Dose of Drugs
Wrong dose rates are used by some fanciers. Baytril and Baycox are two commonly used drugs where fanciers use the wrong dose. Baytril oral syrup comes under a number of different names in Australia - Baytril, Enrotril etc. They are all identical. The dose of Baytril is 25mg/kg( ie about 10 mg per pigeon.) To give a therapeutic dose (ie a dose that will work) this needs to be given at a rate of 0.4ml/pigeon or 10ml/1 litre of drinking water. Some fanciers mistakenly believe that because someone has suggested a lower dose that the Baytril they are using must be stronger. This is not correct. All Baytril oral syrup products in Australia are the same and the above dose is required for the product to have its effect. Similarly the dose of Baycox is 7 to 15 mg/kg. To deliver this dose, drinking water needs to medicated at the rate of 3ml per litre
We have had some fanciers suggest to us that their birds health problems have been due to grit engorgement. This is not a diagnosis but rather a symptom. Pigeons will gorge on grit in one of four occasions:
1. Overt hunger
2. A nutritionally deficient diet
3. Where a pleasant tasting (often salty) grit is provided as a new supplement
4. Diseases that lead to pain of the crop or first stomach compartment
Fanciers need to then work through these alternatives with their vet to find the solution to their birds problem..
Virkon is the band name of a disinfectant primarily marketed to disinfect poultry sheds. We have had some fanciers contact us saying that they have been advised that putting Virkon in the drinking water is a treatment for Salmonella. This is not the case. I personally have spoken to the product"s manufacturer, Virkon can be safely used in the pigeon loft as a disinfectant and to clean drinkers and hoppers. It has the advantage of not being poisonous if residues are swallowed. Putting the disinfectant deliberately into the drinking water with the belief that this is treating a bacterial infection of the bowel is erroneous.
In the early 1990s the Australian Pigeon Company (APC) produced the first pink mineral to be made in Australia. The product is called PVM ( Pigeon Vitamin Mineral) powder. The nutritional requirements of pigeons are well documented and the APC hired a nutritionist to blend this product which was subsequently registered. Being registered it means that the product actually contains the exact ingredients listed on the label and also that any claims made on the label have been validated by the appropriate government regulatory authorities. PVM remains the only veterinary made registered pink mineral in Australia. Over the years various individuals and back yard companies have copied PVM powder. Some have given their back yard blends similar names which confuse fanciers. PVM powder is manufactured for the APC by an approved human and veterinary mixing pharmaceutical company. This means the company is registered to manufacture human products as well as veterinary products. Some of these veterinary products are our APC products. Manufacturing this way means that PVM is made to the highest standard. All other pink minerals in Australia are sold by unqualified people who blend their product physically themselves in a workshop. No other pink minerals are registered in Australia. One pink mineral I see offered for sale contains probiotics. This is a nonsense. Probiotics cannot survive in the dry salty environment of a pink mineral supplement . This means that fanciers are paying for something that they are not getting . The sale of all of these types of nutritional supplements is very poorly regulated. Provided no one complains people can pretty well market anything and can make claims that may be outrageous .
In another incident the need for buyers to beware was very well illustrated. One of the products that the APC makes is a water soluble multivitamin supplement. We hired a nutritionist to formulate this for us. However when I got the levels of nutrients back from him I had a query with one of his figures and so to remind myself of this I over wrote on his formula, vitamin PP. Of course there is no vitamin P let alone a vitamin PP. Anyway, things got busy and I forgot about this and we ended up having one batch of labels printed that listed vitamin PP as one of the ingredients. We quickly realised our error, fixed up the query with the nutritionist and corrected the label. The next year I was at the national pigeon show in Brisbane and there at a stand was a guy selling pigeon products. One of the products he was selling was a water soluble multivitamin and listed on its ingredients was vitamin PP! Goodness only knows what that product actually contained but it had a snazzy label on it that was making some amazing claims and fanciers were buying the product.
At another show I actually had a guy who did not know who I was try to sell me a product telling me that it was made by me!
Pigeon fanciers are a weird mob when it comes to getting veterinary medicine. Many are happy to spend quite large sums of money on medication but are hesitant to pay for advice on how to use it correctly. The result is that many fanciers use medication wastefully, inappropriately and incorrectly. In an article just last month in this magazine a fancier who finished in his top 10 in his Federation Championship stated that he used a preparation containing two antibiotics (for respiratory infection) and an anti-canker drug for one day a week, each week through racing. This protocol dissapointingly gives his birds no benefit, wastes the fancier’s money and in the longer term does his loft harm as resistant strains of organisms develop. The only person who probably benefited is the person who sold him the drugs. The difficulty with this sort of thing is that other fanciers read what he did, view him as a successful flier and are inclined to copy him when in fact his birds are doing ok despite what he is doing. The fancier is also failing to effectively protect his birds against respiratory infection and wet canker which was his aim. This probably compromises race performance in the short-term and as mentioned above makes them harder to effectively protect in the future as resistant strains develop.
Many older fanciers regard themselves as semi-experts concerning all things pigeon and it can be very hard to reorientate their way of thinking. New fanciers look to these older established fliers for advice. Just yesterday I had a new flier ring me from Queensland; he had had his birds" droppings checked by a local "expert" fancier who was "pretty handy with a microscope". The "expert" had diagnosed a problem that was in fact impossible to diagnose by looking at the droppings and had also suggested an elaborate treatment protocol.
From a health and veterinary point of view, pigeon fanciers can be a vulnerable lot. Fanciers are bombarded with ads for supplements and medication. One only has to open pigeon magazines from Australia, Europe or the US to see a plethora of advertisements for various supplements, often promising drastic increases in performance. I have seen such ads take up a third of the magazines space. It can be tempting to buy. One product from “the vaults” that readily comes to mind is Colloidal Silver that was advertised in the Australian pigeon magazines for several years. Because it contained the heavy metal, silver, it was highly poisonous and was only taken off the market after authorities banned its further sale. Yet many fanciers used it and even today we have fanciers phoning the clinic and APC wanting to buy some. The supply of products and prescription medications in some countries is poorly policed. Easy access to remedies and medication not backed-up by accurate veterinary advice promotes misuse and the development of erroneous beliefs that come to be accepted as fact.
I want to tell you a story. A fancier was travelling on a train from Melbourne to Sydney. The train was rattling along when all of a sudden a guy sitting opposite him stood up, opened the window and tipped a small amount of water out of the window from a glass that he was holding. The fancier thinks that that is pretty strange but decides to ignore it. About an hour later the guy does the same again with the water and an hour later he does the same again. The fancier is getting a bit curious at this stage and eventually asks the guy just why he is doing that. The guy replies “ To keep the elephants away.” The fancier replies that “there are no elephants around here” to which the guy replies “exactly, it’s working.”
Fanciers need to be cautious and wary at times and need to critically review product advertisements and claims
Pigeons are naturally robust birds and provided the basics of good care and management and the instigation of basic health management protocols such as parasite control and vaccinations are in place it is often not necessary to continually treat. The control of infectious disease spread through race baskets from entering the home loft needs to be informed and correct. Over the last few years I have been fortunate enough to work, present seminars and simply relax sometimes, with pigeon fanciers in the UK, US, Malta, New Zealand, Turkey, Poland, France, Belgium, Holland, South Africa and China as well as Australia. Pigeon fanciers all around the world are essentially the same. They are fascinated by their birds, want to see them healthy and do well with them. I would like to think that at the Australian Pigeon Company that we can help fanciers with this.
re to edit.
Looking back, it is interesting to note how veterinary pigeon matters have changed over the last 40 years but particularly during the last 10 years. The level of diagnostic ability and veterinary knowledge has dramatically increased and along with this fanciers’ expectations from avian veterinarians have also increased. There is, however, still a surprising amount of misinformation about. Some fanciers are real “gossips”, others are “wannabe” vets and sometimes it seems as if everyone is a veterinary expert. Unfortunately, not all misinformation originates from fanciers, sometimes it is from a vet. Like all professions, the veterinary profession has one or two rogues. Most vets are informed and dedicated to their profession but sadly some are less dedicated and some could even be described as crooks or charlatans. In the past, there were only a small number of qualified avian vets and some fanciers, when they think of avian vets, still think that there are only one or two who can help them with a health problem with their pigeons. There are now, however, about 50 qualified avian vets in Australia. Not all are familiar with pigeon racing but all are familiar with pigeon health problems, the appropriate diagnostic process to investigate these and the correct use of medication. They are able to diagnose medical problems ranging from the minor ones that make race birds a bit less competitive through to the more serious ones where birds are dying. Once a diagnosis has been made, they can then advise a fancier on how the problem developed, how to control it and how to stop it happening again.
At the Melbourne Bird Veterinary Clinic (MBVC), there are four veterinarians and three of these are qualified avian vets. When dealing with a health issue, it is always a matter of correlating the degree of diagnostic effort and expense with the severity of the problem. If the birds are racing well and we are simply monitoring health, then just a general examination and a microscopic examination of a crop flush and faecal smear may be all that is required. Other tests can be done if indicated after examination. With more serious problems, the following is the diagnostic protocol that is followed at the MBVC. This is typical of a thorough diagnostic investigation in most avian practices and can be used as a guide for your veterinarian.
The 12 step process to investigate a serious pigeon health problem
1/ Take a history and develop an understanding of the nature of the problem.
2/Conduct a thorough clinical exam, make assessment of general clinical condition, undertake a microscopic exam of fresh faecal smear, conduct a faecal flotation, undertake a microscopic exam of fresh crop aspirate, check pharyngeal tonsils and laryngeal mound (redness, swelling, abscessation, sialoliths, etc.) in particular.
3/Collect throat, conjunctival (eye) and choanal (‘slot’) swabs for Chlamydia and Mycoplasmal PCRs.
4/Collect blood for full haematology and biochemistry – this gives valuable information about nutrition, the level of training and overall fitness, hydration, organ function, the immune system and infection. This information cannot be gathered from autopsy.
5/ Euthanise bird by giving lethal injection; usually pigeons just “fall asleep”.
6/ Wait 2 hours to do the autopsy; earlier leads to passive bleeding, identified as “congestion” by pathologists, which can make interpretation of tissues microscopically difficult or impossible.
7/ Autopsy within 4 hours of death, later can lead to early autolytic (decomposition) changes and altered bacterial populations, decreasing diagnostic value.
8/ Collect full set of tissues including -- whole head (after removal make a longitudinal incision along the top and back of the skull and crack the skull open to allow formalin to run into the brain case), the anterior oesophagus (sometimes this is the only place you will find Herpes), sections of crop wall, proventriculus, gizzard, several sections of gut, caeca (vestigial) and bursa of Fabricius if visible (i.e. bird <5 months old), trachea, syrinx, lungs, air sac, spleen (often best to collect on first opening the abdomen, if there is bleeding spleen can later be hard to find), liver (left and right lobes), kidney, middle-third of femur (for bone marrow), sciatic nerve, section of spine, skin, heart and pectoral muscle.
9/ Collect PCR for Rota in case you get hepatocellular necrosis of unknown cause; does not matter if the bird is vaccinated against Rota as the PCR does not check for the tiny part of the genome that codes for the capsid VP8 protein that forms the basis of the subunit vaccine. Birds can be negative for Rota on faecal PCR and positive on hepatic PCR. Collect kidney and bowel PCRs for PMV PCR testing.
10/ Collect a second set of the main tissues and freeze these. These are used if further viral identification and testing are required
11/ If anything looks abnormal, target that and make sure a section/sample is collected.
12/ If anything looks infected, collect a swab for MC and S (microscopic examination, culture and antibiotic sensitivity) testing. Collect a similar swab of the gut content.
Everything costs money. It is important that the client’s money is spent wisely and so the samples collected in points 3, 9, 10 and 12 above are held and available if the other tests, in particular the blood profiling and histopathology, are not diagnostic. These samples cost nothing to collect, store well and some can only be collected from a dead pigeon. Overlooking the collection of these may not only compromise the diagnostic process but may necessitate killing another bird unnecessarily to subsequently collect these samples.
Sometimes fanciers have an unrealistic expectation as to what can be diagnosed by fairly basic tests. Sometimes vets are overly keen to give fanciers a diagnosis and make impossible diagnostic claims after inadequate sampling and testing. From a mailed in dropping sample it is only possible to definitively diagnose (and even then, not always) some worms and coccidia. It is not possible to diagnose (or rule out) bacterial or fungal infections. In particular, Streptococcus and Salmonella infections ( just because the organism may be present in the droppings does not mean it is causing disease ) cannot be diagnosed this way. To consider diagnosing any form of canker or respiratory infection in this way is just ridiculous. Any vet who claims to make this diagnosis in this way is deluding not only the fancier but also himself. Similarly it is not possible to diagnose bacterial or fungal infections from a mailed-in throat swab.
I am often asked to review cases and offer a second opinion. Most vets do really great work but the standard of work of some is well below the average of what the profession would expect. A recent case illustrates the point. A fancier was experiencing both poor results and poor returns in his race team. He went to the trouble and expense of sending a live pigeon to an avian vet interstate for diagnostic investigation. On arrival, the bird was handled and droppings were looked at under the microscope. The bird was then euthanized, autopsied and some tissue samples collected for histology (microscopic examination). The pathologist reported that many of the samples were “congested”. From this diagnostic work, the vet was happy to make a diagnosis! He diagnosed that the bird had come in contact with a toxin and asked the fancier to send some grain for testing. The grain was placed onto a medium that stimulates bacteria and fungus on the surface of the grain to germinate. This test is not regarded as an accurate way of assessing grain quality or an accurate measure of fungal or bacterial contamination. But from this test, the vet advised the fancier that the corn was a problem. The fancier stopped using the corn. Nothing changed and the fancier then re-contacted the vet who advised that it was a “very complex” problem and another bird would need to be sent for testing. The fancier then contacted the MBVC.
The vet had not necessarily done anything wrong but most vets would regard his diagnostic investigation as pretty poor. Comparing his work with the above recommended 12-point protocol, many problems are apparent. The main ones are listed below.
Problems with this investigation
a/ Inadequate collection of samples required for an accurate diagnosis. When asked why various samples were not collected, his reply was that “he would rely on the histopathology” for a diagnosis. A seriously flawed approach with many potentially relevant and important things being overlooked.
b/ Poor autopsy technique – when asked if the “congestion” noted by the pathologist was apparent at autopsy or if he had caused it, his simple reply was “I don’t know”. Many important tissue samples were not collected during the autopsy. Yet, despite inadequate tissue collection and poor tissue handling, this was his main diagnostic test.
c/ His preparedness to make a diagnosis that was impossible based on the test results.
What concerned me is that when I contacted the vet in question, he thought he had done a good job. Unfortunately, he had become professionally isolated and his knowledge and diagnostic approach were no longer in step with the profession’s expectations. The frustrating thing for me was that he did not seem to realise this. He seemed simply out of touch with the diagnostic process and also with the standard way that most avian vets would approach this problem. On top of this, some of his testing and advice was flawed and often just wrong and certainly not consistent with what would be regarded as acceptable practice in the profession generally. Veterinarians as professionals may differ in the exact way that they diagnose and manage cases but in this instance the tests being done and treatment recommended did not have a scientific basis. He was substituting his opinion for scientific fact. I found it particularly interesting that he was quick to label this a “complex case”. These days, nothing should really be complex given the correct testing. These days, diagnostic testing is so sophisticated that it is simply a matter of following the usual diagnostic pathway and getting the results.
And so what was wrong with this fancier’s birds? The haematology component of the blood profiling revealed a very high PCV. This stands for Packed Cell Volume and is an indicator of the concentration of red blood cells in the circulation. When PCVs get high, the blood becomes more viscous and the heart has to work harder to pump it around the body. This puts a dramatic increase on the work load of the heart and leads to cardiac insufficiency during exertion and an obvious compromise of race performance. This condition is seen quite commonly. The exact cause of these high PCVs is not known but one suggestion is that it is the response of a pigeon being forced to exercise beyond its fitness or health capability. The condition usually responds to treating any identified health problems ( that are blocking the development of fitness) and simply to just open lofting. Affected birds are kept in their loft routine, i.e. let out and called in at their normal times but are not forced to fly. Leaving birds at liberty for several hours a day I find is a good stress reliever and helps the birds to gradually fly themselves to fitness – those that want to fly do and those that want to rest can, as they start to feel well they fly more and develop their own fitness. During this time, there is no rationing of food. Birds are fed by hand as much as they want to eat twice daily with a moderate protein ration of about 16%, e.g. 40% dun peas, equal parts (about 15% of each) safflower, sorghum, wheat and corn. Usually the condition corrects itself over 2 weeks and the team can gradually be brought back into work. The biochemistry component of the blood profile showed minor damage to the liver and reduced kidney function but histopathology showed no significant damage at a cellular level and subsequent Rota and PMV PCRs (viral DNA checks) ruled out these viruses as being involved. All other tests did not reveal any other complicating factors. There was no evidence of a “toxic” exposure.
Moving on from this I have even reviewed cases where vets have invented conditions and then advertised that they are the only ones to be able to diagnose that condition and in turn, market elaborate treatment programs to manage the condition.
A list of qualified avian vets in Australia and New Zealand is listed on the Australian Pigeon Company website. I would encourage all fanciers to use their services but at the same time, if the advice you are getting just does not sound right, get a second opinion.
The importance of correct PMV vaccination
This mini-disease outbreak raises several important issues regarding PMV vaccination. The initial reaction of some fanciers after hearing that the problem was PMV was to conclude that the vaccine was either not effective or that alternatively, we were dealing with a new strain of PMV. Both conclusions are incorrect. There is sufficient genetic overlap between various PMV strains that the vaccine would be effective against any strain. To blame the vaccine is a bit like putting 4 stroke petrol into an engine designed for 2 stroke fuel and then when the engine does not work concluding that there is a problem with the fuel . Like petrol, for a vaccine to work it has to be used correctly. Fanciers are reminded that the killed La Sota PMV vaccine if used correctly is 100% effective. The correct vaccination method is to give 2 shots about 4 weeks apart with both shots being given after 6 weeks of age. This doesn’t sound that hard but some fanciers seem to have trouble following that advice.
Issues regarding PMV vaccination
1/ Do not vaccinate too young
If youngsters are bred from vaccinated parents some of the parent’s immunity passes to the babies. This “passive” immunity interferes with the youngsters developing their own active immunity from vaccination. Thorough testing in 2012, done in Australia, showed that this passive immunity lasts until the babies are about 6 weeks old. A fancier, therefore, giving a young pigeon its first shot under 6 weeks of age cannot be guaranteed that this first shot will work. It is reasonable to give the first shot at 4 weeks at weaning, particularly in a high risk situation but if this is done 2 further shots will need to be given to ensure the development of protective immunity. Remember the birds need 2 shots after 6 weeks of age to be immune.
2/ Importing European vaccines.
In Europe PMV vaccines are available that are made from pigeon origin PMV strains. The advantage of these vaccines is that if birds are vaccinated with these and are exposed to PMV they are less likely to develop into “silent” carriers ie they are less likely to be transient carriers of the virus. The vaccines that are available in Australia stop the birds getting sick with PMV but if exposed they do become infected with the virus for a short period ( several weeks ).This temporary carrier state does the birds no harm but it does mean that they can spread the virus. This is less likely to occur with the European pigeon origin vaccines.
I am aware that some fanciers have imported this vaccine for use in their own birds. Importation of vaccine into Australia is illegal. I don’t want to be critical of these fanciers. I can perhaps understand why fliers have been tempted to do this and feel that probably those involved did not understand the potential ramifications of their actions. I will explain below why this practice should not continue and hope that once they understand the situation that they no longer choose to do this.
Importation of vaccine into Australia is illegal, and for good reason. Vaccines are developed and held in media that are ideal for the growth and maintenance of the virus in the vaccine. This preparation is also attractive to other viruses. This means that there can be no guarantee that there are no other viruses present in the preparation as well. Bear in mind that there can be up to 17,000 different viruses in a single glass of water. It is impossible to check for all of these. Australia does not want to introduce any new viruses. Fanciers who smuggle in a European vaccine illegally will in due course inject their own pigeons and these, with time, will mix with birds from other lofts particularly during racing. This is a great way to introduce and spread a new virus across the country.
Another thing to consider is that vaccines are very fragile. PMV vaccines need to be kept at specific temperatures. It takes 5 days to post a vaccine from Europe to Australia. I feel that the chance of the posted vaccine being within the temperature range required to keep the vaccine fully potent for the whole time is low. Even if ice is still present in the parcel this does not guarantee that the vaccine is OK. If ice sits against the vaccine container it can locally freeze it, which, depending on the vaccine, can reduce the vaccines effectiveness.
Fanciers who smuggle vaccine into Australia therefore risk not giving their birds an effective vaccine and subsequently losing their birds either through the birds catching the disease or alternatively having reduced immunity, inadequate protection , sub clinical disease if exposed to PMV and impaired race performance. This of course is not to mention the risk that they impose on the rest of the Australian pigeon community through introducing another exotic virus.
Now that the situation has been explained I would be very disappointed if the illegal importation of vaccines into this country continues. The smuggling of vaccines into this country by any fancier is to be strongly condemned.
3/ Yellow lumps at the vaccine injection site
At the Melbourne Bird Veterinary Clinic we have seen and tested many of these birds now. Without exception they have turned out to be infections. Pigeons don’t have the enzymes in their white blood cells to produce liquid pus like a mammal. Pus in birds is thick, yellow and cheesy. People blame the vaccine for the formation of these yellow lumps but of course this makes no sense. It is common sense that if the yellow lumps were caused by an innate feature of the vaccine then it would affect all lofts to a similar extent. I see on the internet fanciers condemning the vaccine because they get a lot of birds with yellow lumps after vaccination. One fancier actually stated that a third of his birds got them. All they are announcing to the world is that they have a poor vaccination technique. If the needle becomes contaminated between pigeons with dust from the loft, or is touched or is injected too deeply into the crop then it will be contaminated with bacteria and infect subsequent pigeons. The tip of the needle should go just below the skin and when correctly injected a white ‘flare’ should be seen just below the skin. There is no need to attempt to sterilise the skin with disinfectant as pigeon skin is virtually sterile anyway. If concerned, fanciers should just change the needle every 10 or so pigeons or whenever they think it may have become contaminated. Needles literally cost less than 5 cents each. This means that even if the needle is changed for every pigeon it costs less than $5.00 for 100 pigeons. Hardly a big expense.
4/Fake veterinary news
Several years ago some information was spread, I am sorry to say , by a veterinarian that although it was necessary to vaccinate now in Australia against PMV, that the vaccine in some way, by an as yet unknown mechanism, altered the development of natural immunity in young pigeons. The vet went onto explain that as a result these pigeons were more vulnerable to disease and it was now necessary to use new methods and products developed by him to counter the damaging effects of the PMV vaccination on immunity. This information which can be described as fake veterinary news was presented as veterinary fact when this was just not the case. It was purely personal opinion. The veterinary profession as a whole does not believe that this is the case, there are no studies showing that this happens. The proposed mechanism is unknown because it does not exist. It is all just a hoax. Unfortunately the fake news led to many fanciers not vaccinating their pigeons. Some of these subsequently lost significant numbers of birds to the disease. As a veterinary colleague of mine at the University stated, the vet who spread this false information has the blood of hundreds, if not thousands of pigeons on his hands. It is worth remembering that some Victorian doctors, several years ago, that spread misinformation that led to some parents not vaccinating their children were struck off. The irony of it all is that the multimillion dollar vaccine companies that make the vaccines put a lot of time, effort and money into ensuring that the base that the vaccine is in, be it oil or otherwise actually enhances the immunity formed by the vaccine itself. These vaccines then have to pass the extremely rigorous testing protocol demanded by the Australian authorities before market release with safety of use being a top concern. In a conversation with the Pfizer manager in charge of distribution of the company’s products throughout the Australia-Pacific region, he explained that the company was concerned about the unfounded criticism of one of their vaccines and that legal action against the veterinarian concerned was an option.
5/ Live (NDV4) vaccines vs killed La Sota vaccines
When we did the 18 month long PMV vaccine trial in 2012 we found that when pigeons received a single dose of La Sota vaccine, 70% were fully immune in 4 weeks. When they were given a second shot 4 weeks 100% became immune. Conversely when the pigeons were given NDV4 none were immune after 4 weeks. When given a second shot most but not all became immune and the level of immunity that developed was not as high as that produced by the La Sota vaccine. Recently some people have been advocating the use of NDV4. My simple answer is why – particularly when there is a safe, more effective vaccine available. Some Queensland fanciers have suggested that because NDV4 is alive it can give the pigeons the disease. This is nonsense. The live virus in the vaccine has been modified so that it cannot cause disease. The only way that use of the NDV4 vaccine can cause disease is that if it is used, because it fails to cause the development of immunity in all pigeons this means that if they are exposed to PMV then some of them will get sick.
The simple answer to all of this, is that unlike other diseases, notably Rota virus, where a completely effective vaccine is still a work in progress, we are a bit spoilt with PMV. We have a safe, effective vaccine that has been extensively trialled. These trials were completed 7 years ago and the result of these trials was made widely available being published in the national pigeon magazines and also the peer reviewed Australian Veterinary Journal.
If fanciers have any comments, queries or questions about PMV vaccine use they are more than welcome to contact me. I am happy to reply and comment. In the meantime prevent PMV killing or damaging your birds by using the killed La Sota vaccine . The Australian brand names are “Poulvac and “Newcavac” and remember it is 2 shots about 4 weeks apart with both shots being given after 6 weeks of age and then annual boosters.
Dr Colin Walker