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. Insular Fanciers. 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 Water Problems 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. Canker Reoccurring. 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.
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AuthorDr Colin Walker Archives
October 2020
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