Diagnosis Of Disease
By Dr. Colin Walker B.Sc. B.V.Sc. M.A.C.V.S (avian health)
In Australia there are
approximately 24 practicing, qualified avian veterinarians. This may
sound like a lot but Australia is a big country. Looking through my
clients details shows that 50% live more than 50 miles from the
clinic and 10% live more than 500 miles from the clinic. This means
that it is not always possible to bring sick birds in and so a
proportion of my day is spent speaking to fanciers on the phone. It
is surprising how often, with fanciers accurately relating what they
are seeing that advice can be given. Many times however this is just
not possible and testing is necessary in order to give accurate
Many fanciers I find are keen to
buy drugs but are reluctant to spend money on diagnostic tests. Yet
spending money on diagnostic tests often provides the most
economical way of solving a problem. Money is not spent on
unnecessary expensive drugs, time is not wasted and good birds are
not put at risk through delayed or inappropriate treatment. It can
be frustrating when a fancier describes very non- specific symptoms
such as that his birds are quiet and fluffed and then asks what
medication he should try. So many things could cause this symptom.
Sometimes incredibly, fanciers with sick birds ring the clinic
asking for a particular medication and when asked why, state simply
that another fancier whose birds were also sick used it and they
got better. It is frustrating when such fanciers decline testing to
see if in fact their birds problem is the same. To me this makes no
And so how
are pigeon diseases diagnosed these days? Respiratory infection is a
common problem in racing pigeons. If the birds are sneezing how do
you know if it is a respiratory infection or just dust etc? The most
common cause of respiratory infection in pigeons in Chlamydia. These
days this can be diagnosed very specifically in many ways. A common
thing to do is draw a drop of blood or scrap some cells from the
bird’s eyelid or throat and run what is called a Chlamydia PCR test.
This accurately tests for Chlamydia DNA in the bird. Alternatively,
another test called a Chlamydia Immunocomb is done. This is done on
a drop of blood and tests for Chlamydia antibodies. The antibodies
are found in the blood in response to exposure to Chlamydia. This
test only takes about 4 hours to do and costs the equivalent of 22
pounds or about 60 dollars.
tests are negative and a bacterial or fungal infection is suspected
a test called a sinus flush can be down. Here sterile saline is
flushed into a nostril. Pigeons to not have a septum dividing their
nasal passages (as some other birds such as finches do) and so this
saline flushes through the nose and comes out the other nostril in
the process washing out any bacteria or fungi present. These can
then be cultured and identified. Once a name has been put to the
bacteria we then know the whole biology of that bacteria For example
we know what was the likely source of the infection e.g. a bacteria
called Pseudomonas often comes from water while another called
Camphlobacter can come from wild birds. Accurately identifying the
bacteria means that steps can be taken to avoid repeat exposure so
that the problem is less likely to come back after antibiotic
treatment. Once cultured, the bacteria can also be tested against a
number of antibiotics to see which is the most effective at killing
it. This takes away the guess work and means that a short antibiotic
course is very likely to be effective.
Chlamydia tests and sinus flushes, swabs for bacterial culture can
also be taken from the choana (the slot in the roof of the mouth).
This is the bottom opening of the sinuses and sinus fluid drains out
through it.A swab collected from here represents pretty well the
bacteria in the sinuses themselves.
for biochemistry and hematology are widely used in avian medicine
these days. Blood is usually drawn from the right jugular vain. A
simple formula tells us that a birds blood volume in mls is about
10% of its weight in grams. This means that a 400 gram pigeon has
40mls of blood. About 10% of the blood can be safely drawn at any
time. This means we can draw 4mls quite safely from a racing pigeon.
The labs these days however are so sophisticated that entire blood
profiles can be done on as little as 1/2ml or less of blood. We
routinely do complete blood profiles on budgerigars using only a
1/4ml of blood. One interesting fact is that pigeons can make their
whole blood volume in 24 hours. This mean that if 10% is taken 10
times in one day they will still be ok. Incredible. They can make
blood very quickly.
biochemistry/hematology profile tells us things like how the
kidneys, liver and pancreas etc are working and also blood sugar,
cholesterol, total protein, red and white blood cell counts and
other values. Running a profile is not cheap. In Australia it costs
$120 i.e. about 50 pounds. It does however give us a lot of very
useful information and is of great value in figuring out what is
wrong with an individual bird of value.
flushing is another common test. Here a plastic tube on the end of a
syringe is introduced over the back of the tongue and into the crop.
Material is vacuumed out of the crop and can be examined under the
microscope. This is the test that is used to monitor trichomonad (i.e
canker organism) levels. The aspirated material can be examined
directly under a microscope or alternatively stained or cultured. In
this way bacterial infections, yeast infections and inflammatory
cells can be detected.
are a big part of any fancier’s life. Droppings for most fanciers
are the most accessible and visible indicators of their bird’s
health. Tight brown ‘nut like’ droppings with white urine and
preferably a down feather stuck to them usually mean good health.
Green watery droppings alert the fancier to a health problem.
Examination of the droppings under the microscope takes an
experienced veterinarian less than a minute and is an excellent way
to check for worms and coccidia. If the droppings are less than 10
minutes old they can also be used to check for Hexamita (a canker
like organism in the bowel). Yeast and bacterial populations can
also be estimated and if necessary stained and cultured to evaluate
these further. Canker and respiratory infection cannot be diagnosed
through the droppings.
of further diagnostic tests are available- Circo virus can also be
tested for from a drop of blood, dead birds can be autopsied and
tissue samples collected for pathology, eggs can be autopsied,
endoscopes can be used to examine live birds internally, birds can
be x-rayed and samples for bacterial culture can be collected from
fanciers when consulting an avian veterinarian want one of three
of several race birds for common disease
check several representative birds from the race team, which may
actually look quite normal, to see if they are carrying any health
problem that will compromise performance. Usually a crop flush
aspirate and droppings are examined microscopically and a drop of
blood is drawn for a Chlamydia Immunocomb test.
simple tests allow us to check for all of the common diseases.
birds have become unwell with maybe some dying and an accurate
diagnosis is needed.
history i.e. the circumstances of the disease outbreak and the
symptoms shown by the birds may point us in the right direction.
Testing can then be used to confirm suspicions. Often in this
situation autopsying a freshly dead bird or culling an unwell bird
that we feel is going to die is the quickest and most economical way
of reaching an accurate diagnosis. To be diagnostic, tissue samples
need to be collected within 4 hours of death. During autopsy tissue
samples form all organs are collected and fixed in formulin and any
obvious infection is swabbed for culture. All of these samples are
then forwarded to an appropriate laboratory for testing. Do make
sure your vet forwards these samples to a pathologist with alot of
avian experience. This really is the definitive test and it is rare
for this to not fully and accurately diagnose the problem.
Individual birds of value that have become sick and need to be
diagnosed, treated and made well.
we still see fanciers that believe good birds never become sick.
What a load of rubbish! We see 700 mile open winners that
subsequently become unwell. It makes no sense to deny these birds
treatment An initial thorough clinical examination often indicates
to us which diagnostic tests are likely to give us the most
information and are the best use of the fanciers money. Usually with
valuable individual birds blood is drawn for biochemistry and
hematology and also scanning whole body x-rays are taken. Often this
combination of tests will diagnose the problem or at least indicate
a more specific test e.g. a liver biopsy that will definitively
diagnose the problem. Sometimes with these birds their problem can
fixed with medicine, sometimes the answer in surgery. These days the
risks involved in birds with anesthetics and surgery is similar to
those in dogs and cats and we routinely repair hernias, remove
tumors etc. so these birds can regain their health.
I urge fanciers to
develop a good working relationship with an experienced avian vet.
Accurate diagnosis and effective treatment can only be an advantage
to you and your birds.ody