Margaret A. Wissman, DVM
Excerpt from BIRD TALK Magazine, August 2010 issue, with permission from its publisher, I-5 Publishing.
While we always strive to watch our birds closely for any changes in appetite, droppings, vocalizations, feather condition or behavior, we must have them examined and tested from time to time by an avian veterinarian to uncover any sub-clinical diseases or conditions before they become dangerous or threatening to our birds’ health.
Based on the history that you give your veterinarian, any changes or signs that you have noticed and the results of a physical exam, specific tests will be recommended. These tests may uncover a potential problem that, if otherwise left undiagnosed or untreated, could save your bird’s life.
Complete Blood Count
In my opinion, this is probably the most valuable test that an avian veterinarian will run. The good news is that the complete blood count (CBC) test can be run on just about any bird, even the smallest finches or parrotlets.
The first portion of the CBC is the packed cell volume (PCV or hematocrit), which tells us the percentage of red blood cells (RBC) in the blood. From this test, we determine if an animal is anemic (lacking enough red blood cells) or dehydrated, for example. Blood is drawn up into a thin glass tube, called a hematocrit tube, and then the blood is spun down to separate the solids from liquid in the blood. If the white blood cell portion is elevated, this may be observed by an increase in the length of the buffy coat. The plasma, which is the liquid portion of the blood, may contain fats (called lipids) and may also appear a different color than usual.
The 5 tests your bird needs are the CBC test, the plasma chemistry panel, bile acids test, psittacosis test, and one large group test: radiographs, ultrasound, CT scan, and MRI.
When the blood smear is evaluated, we can tell if a bird has an increased number of immature red blood cells, if there is a chance of lead toxicosis or if there are parasites in the bloodstream as well as other valuable information.
The white blood cell (WBC) count can give us a lot of valuable information. If the WBC is elevated, this can indicate stress, bacterial or fungal infection or even certain types of cancer. If the WBC is low, this can indicate a viral problem or certain chronic conditions. The percentages of the five different types of white blood cells and their absolute numbers are also very helpful in diagnosing certain diseases, the state of a bird’s health and whether or not the bird has a chronic or acute problem.
A veterinarian can learn so much about the state of a bird’s health just by a simple CBC. As far as I am concerned, this test gives us the most bang for your buck. Avian veterinarians skilled in the interpretation of this group of tests will learn much from the CBC.
Vets new to avian medicine are encouraged to take advantage of the free consultation service offered by the larger veterinary diagnostic labs that perform testing on birds. Several diagnostic testing labs will offer a consultation service making avian veterinary specialists available to vets who utilize the lab to answer questions about a case, including how to safely draw a blood sample, and how to interpret the results. It helps for the vet who sees just a few birds or who is new to avian medicine or for the vet who would just like another opinion on a case. An avian specialist who reads literally hundreds of avian CBCs per month may be able to discern subtle nuances from the CBC that may be missed by a practitioner.
Plasma Chemistry Panel
Many different plasma chemistry panels can assess the organ function of any bird using a very small volume of blood. A blood sample, drawn from a vein, is placed in a small tube with an appropriate anticoagulant. The blood is spun down to separate the blood cells from the liquid portion. Many tests can be run from this plasma sample, including tests for liver function, kidney, muscle damage, proteins in the blood, albumin and several different electrolytes, including calcium levels. These tests can help pinpoint problems non-invasively.
This is another test that is run on plasma and is used to assess problems with the liver. The other chemistry tests for liver are more open to interpretation but the bile acids test is very specific for liver function. If the liver is not functioning properly, this test can be very diagnostic, perhaps followed by liver biopsy.
Many birds, especially the smaller psittacines may be carriers of the primitive bacteria, Chlamydophila sp., which is contagious to humans. While no one specific test will diagnose a bird as having illness from Chlamydophila, always screen a bird for this disease, especially in families with children, geriatric family members or those who are immunocompromised. In conjunction with the CBC, chemistry panel and/or radiographs, ultrasound and bile acids, the test for psittacosis can provide valuable information regarding your bird’s total health.
Tests can detect the organism in the environment, in the bloodstream or from excretions (ocular, nasal, choanal or cloacal/fecal). Two titers (blood tests that measure antibodies) exist, one for acute disease and one for chronic infections. Another test looks for the organism in fresh droppings. Sometimes several tests may be necessary. In some cases, because it is impossible to diagnose psittacosis in a live bird, it may be advisable to treat a bird or family flock that lives in a home with people who would be adversely impacted if infected with psittacosis with doxycycline for 45 days, to prevent a bird or birds from shedding the organism into the environment. Discuss this with your avian veterinarian.
Radiographs, Ultrasound, CT Scan, MRI
This group of tests allows veterinarians to "see” inside the body non-invasively. These tests can identify masses internally that may be tumors, granulomas, eggs, foreign bodies, parasites or can detect abnormally sized or shaped organs. Bones and muscles can be checked for developmental abnormalities, fractures or dislocations. If problems are identified, surgery or laparoscopy can be performed for more detailed diagnosis.
Have your pet birds seen by an avian vet on a regular basis. By judicious use of the above-mentioned tests, problems can be identified and treated before they become life-threatening, for the most part. Of course, other tests are routinely utilized, including the Gram’s stain, urinalysis, heavy metal testing, bacterial culture and sensitivity and fungal isolation.
The results of your bird’s history, presenting complaint and physical exam results will all be utilized to decide which tests should be performed.
Proactive Bird Care
- Offer a quality, species-appropriate, balanced bird food.
- Provide ample fresh clean water all the time, preferably from a water bottle.
- Groom your bird periodically
- Take your bird in to see an avian veterinarian regularly.
- Weigh your bird weekly — it is one of the best ways to catch something early, when it is easier to identify and treat.