ARTIFICIAL
INCUBATION AND HAND-RAISING
By Dr Colin Walker BSc, BVSc, MRCVS, MACVSc
(Avian health)
With breeding about to start, we all
know that sometimes things don’t proceed as smoothly as we
might like. An abandoned egg or youngster can be a particularly frustrating
experience for a fancier, particularly if it is from one of the more
important pairs. For many of us, the only available option to try
and save the youngster is to foster it under another pair. To have
any real chance of success, however, there should be no more than
48 hours, and preferably 24 hours, difference in the reproductive
cycle between the foster pair and donor egg or youngster. Of course,
such a pair is not always available. This situation need not necessarily
mean that the youngster will be lost.
In the past, if a foster
pair was not available for an incubated egg or a young nestling,
it was not considered practical to raise the chick independently.
However, with the availability of relatively inexpensive incubators
and nutritious artificial hand-raising diets, it really becomes the
fancier’s choice as to whether or not
he wants to save the youngster by taking over the role of egg incubation
or rearing of the chick.
The situation is eased somewhat if the egg has not been incubated.
If development has not started, the egg does not need to be kept
warm to remain viable. Eggs can be stored for several days waiting
for a foster pair to lay. Eggs should be stored in a cool, dry
place with the pointed end up at approximately a 45?q angle and
turned at least twice daily (alternating left and right). Once
the foster pair lays, the stored egg can be placed under them and
development will commence.
If no foster pair is available, artificial incubation should be
considered. A number of ‘hobby’ incubators are available
(with readily available brands being Brinsea, Novital, Multiquip
and Masalles) through a number of outlets. Prices vary depending
on the amount of automation but it is possible for between AUD$500
and AUD$1000 to buy one that not only maintains the correct temperature
and humidity but also turns the egg. The temperature and humidity
parameters used for chickens work well in pigeons (and indeed most
bird species). Temperatures of 37.2 – 37.5?qC and humidity
levels of 55 – 60% are suggested. Automatic turning devices
will turn the egg up to 25 times per day. Incubation procedures
for the bulk of the incubation period are relatively straightforward
and rely only on regular turning and the maintenance of adequate
temperature and humidity levels. This routine only changes 2 – 3
days before hatching when the egg should no longer be turned and
the humidity is raised to 70 – 75% (either by increasing
the exposed surface of water or by decreasing the ventilation in
the incubator). Humidity is usually measured with a hygrometer.
Incubators can sometimes be used as a useful stop-gap measure until
a foster pair has been organized or alternatively their use can
continue until hatching.
Once successful hatching has been achieved, if no foster is available
to raise the chick, then both warmth and food must be provided
artificially.
Heat can be provided by a converted incubator, a pet heating pad
or a container (even a cardboard box is fine) with an incandescent
bulb. If using a bulb, the heat can be altered by changing the
height of the bulb above the chick, the wattage (strength) of the
globe or using a thermostat. A temperature between 32?qC and 37?qC
should be maintained. Newly hatched chicks do better at the higher
end of the scale. Humidity is best supplied by providing a source
of water near the heat source such as a small jar of water. Chicks
that are too cold will become poorly responsive and feel cold to
the touch, and when very cold start to display a reflex involving
repeated opening of the beak. Hot youngsters also become poorly
responsive and become a bright pink colour. Youngsters older than
7 days will also pant.
To feed the chick, an artificial beak needs to be created. This
can easily be done by cutting off the needle attachment on the
end of a syringe. Different syringe sizes are used as the chick
grows. The regurgitation of the parents is mimicked by depressing
the syringe plunger as the chick eats, as shown in the diagram.
The diameter of the opening should be such that the chick’s
beak is able to fit inside the tube opening and open up inside
the tube body. The chick will then drink the hand-rearing formula
in which its beak is submerged.
INSERT DIAGRAM HERE
For purposes of feeding, the growth period in the nest can be
divided into four stages. Initially the hand-rearing formula must
mimic ‘pigeon milk’. Pigeon milk is high in protein
and fat, with a high water content. Carbohydrates are virtually
absent. As the chick grows, the diet becomes progressively more
similar to the adult diet. Gradually, the level of protein and
fat decreases while carbohydrate and solid matter levels increase.
A number of diets are commercially available. A commonly used brand
is Roudybush (Dr Roudybush is an American vet who established and
runs a bird food manufacturing company). Two suitable formulas
are Roudybush Squab Handfeeding Formula (which is essentially a
pigeon milk substitute) and Roudybush Formula 3. These and other
similar diets can be purchased from specialist bird outlets.
The four stages are:
Stage 1:
Hatching to 4 days
Roudybush Squab Handfeeding Formula.
Diluted 2.2 parts water : 1 part formula by volume
Feed five to six times daily
Note: Some hatched chicks can survive off the resorbing yolk sac
for 24 hours. Some people prefer to give an initial feed of either
saline or Hartmann’s solution (available from vets or a pharmacist),
particularly if the chick appears dehydrated (deep red and poorly
responsive, more likely to occur with a prolonged hatching).
Stage 2:
Early growth, 5 – 7 days
Roudybush Squab Handfeeding Formula.
Diluted 1.5 parts water : 1 part formula by volume
Feed four to five times daily
Stage 3:
Late growth, 8 – 14 days
Roudybush Squab Handfeeding Formula.
Dilute 1 part water : 1 part formula by volume
Feed three times daily
Stage 4:
Fledgling, 15 days – weaning (28 – 30 days)
Roudybush Formula 3
Initially dilute at the rate of 1.2 parts water : 1 part formula by volume
and reduce the amount of water as the chick ages.
Feed from 3 times daily down to once daily and start to provide normal adult
seed mix.
Through all stages, it is a good idea to add a probiotic (eg Probac)
to the dilution water for at least one feed per day.
And so, is it all worthwhile? From personal experience, it is
a lot of work and the youngsters at weaning do tend to be slightly
less robust than those that are parent-reared. Once weaned, however,
and eating independently, they do quickly compensate and catch
up and are certainly quite raceable. This procedure is, however,
best reserved for those special youngsters. I guess it all depends
on the value placed on that particular youngster by the fancier.
It is nice to know, however, that the options of incubating and
hand-raising are now practical ones.
Special thanks to Dr Danny Brown for some of the technical information
presented in this article. |