Back Home Up Next

Recommended Vet Tests


Pamela Clark



"When a client comes to you and thinks he has a parrot that is feather picking for behavioral reasons, what veterinary tests do you want to have seen done to rule out physical causes before you are comfortable going forward with behavioral modification?"



By the time someone calls me for a behavioral consultation, they have usually been to a vet who has done some testing, and has provided the opinion that the plucking is "behavioral." They often tell me, "The vet has done ALL the tests and the bird is completely's behavioral!" Having previously considered themselves loving, conscientious parrot owners, they are perplexed and feeling slightly guilty and very confused. Further, they have often already spent lots of money to arrive at that opinion.

My first question is...."If ALL the tests have been done, what were they?"

Invariably, the owner doesn't know. In fact, I have never had one client be able to answer this question. I would stop here for a moment and term this one of the worst problems in parrot-keeping today. Briefly, each one of us must know exactly what tests are done on our parrots and what purpose the test serves. In the case of featherpicking, we must know what physical cause each test is supposed to rule out. There is great diversity in experience and knowledge among avian veterinarians, and the wise owner will oversee her parrot's care with a proactive attitude. That means asking questions with patient persistence, and making sure that our birds are handled gently. If an owner's vet will not take the time to explain what he is testing for and why, I suggest that person find another vet.

The following story will serve to illustrate this point:

I received a call from an intelligent, well-informed African Grey owner. Her seven-year-old female Grey was feather picking. She had seen two different vets about the problem. The first had performed cultures, a gram stain, and a blood panel (which did not include any determination of heavy metal toxicity) . He had referred her to a second vet, who had done a feather biopsy. Both vets are well-known and well-respected.

However, neither one had tested for aspergillosis, Giardia, zinc or lead toxicity - three of the leading causes of feather picking. Why? Because the science of avian veterinary medicine is still evolving, including the knowledge about the physical causes of feather picking. In many instances, the knowledge a vet has about the physical causes of feather

picking depends largely on how many cases he has had come across his threshold (and has successfully tested and treated) and how much time he spends keeping abreast of advances in this area. Further, it has been a widely-held belief until very recently that most feather picking problems are "behavioral" in nature. Many vets still hold this belief, and as a result, do not always do the exhaustive testing which can be necessary.

Therefore, It is both unfair and unwise to expect that every vet is going to be able to treat a feather picking bird with full knowledge. That leaves us, as parrot owners, as the "bottom line." Each owner of a feather picking bird needs to know exactly what tests have been performed to date for the problem, and what physical cause each of these was supposed to rule out.

Therefore, my first assignment to a new client is to find out what tests have been completed, what physical causes have been ruled out, and then we begin to "fill in the blanks." The most innovative and up-to-date vets are now saying that as much as 70% of all feather picking is caused by physical reasons. Thus, it would be inappropriate of me, as well as irresponsible, to proceed with the assumption that the picking is solely behavioral (even if this statement has been offered by the vet on the case) unless I made a close scrutiny of the tests previously run. On the other hand, I must take into consideration the fact that the owner has already usually spent considerable sums of money on the previous vet visits, without resolution, and may not be happy about being sent back to the vet for more testing.

My preference would be to have owners perform *every* possible test to rule out physical causes before we assume that the cause is solely behavioral. However, the cost of that often runs in excess of $500.00. In cases where it is not practical or possible to rule out every known physical cause right away, I like to see the owner at least test for the following:

Aspergillosis. This is a respiratory fungal infection, caused by the Aspergillus mold. This organism is ubiquitous; spores are everywhere in the environment. It grows readily on corn cob bedding, sold for use in parrot cages, as well as on other organic matter. Since it does occur so widely in the environment, parrots do not usually become infected with the disease (having developed some resistance to it) unless (1) they have some type of massive exposure to the spores, or (2) their immune system becomes suppressed. Massive exposure can occur when corn cob bedding is used, or when fields near a parrot's home are tilled and larger than normal numbers of spores are released into the air. Suppression of a parrot's immune system can occur when the parrot in under increased stress, or when a parrot becomes ill with another infection. African Greys, Blue-fronted Amazons and Jardine's Parrots are three species that appear especially susceptible to aspergillosis infections. Diagnosis of aspergillosis is best made by taking a blood sample, and submitting this to the University of Miami lab. This lab performs a testing procedure which is more comprehensive that the simple test for antibodies which is sometimes done.

Giardia.  As has been described in detail on this list recently, Giardia is an intestinal parasite. It is a fairly large protozoa which, when inhabiting the intestinal tract of a parrot, also creates a histamine response in the parrot. The latter can cause significant itching. However, not all parrots with Giardia display discomfort. Giardia is not as uncommon as many people believe. For instance, in cities and towns that have high water tables and where homes use septic systems for waste disposal, an outbreak of Giardia will occur fairly regularly during years when there is a higher than normal amount of rainfall, causing the contents of the septic tanks to leach into the ground water. Giardia is quite contagious, and the reproductive cysts are extremely durable, able to live for years in the soil and still stay viable and capable of producing disease when coming in contact with moisture again. Giardia is also difficult to diagnose. The most reliable method of diagnosis is the trichrome test, when the sample has been obtained from the first morning's droppings on three consecutive days. (A vet I spoke to recently was of the opinion that it is preferable to collect a sample on alternate days, such as Monday, Wednesday and Friday, rather than three consecutive days.)

 Zinc and lead toxicity. This is another frequently found cause for feather chewing and pulling. Those parrots who are especially "beaky", such as cockatoos and Jardine's Parrots, seem to have a higher than normal incidence of this problem. These species seem attracted to the metal quick-links which hold toys in place, as well as other metals used on toys. One cockatoo with whom I am working presently has a fondness for beaking the inside of the galvanized bathroom faucet in an attempt to obtain water from this source. His zinc levels are three times normal. A diagnosis of heavy metal toxicity is made by performing an avian blood panel, which includes specifically the request for this value. In the case I described above of the African Grey who had seen two vets, a blood panel was performed by the first vet, but no value for zinc or lead were obtained. Therefore, this test had to be performed again.

Infectious diseases, such as Polyoma, Chlamydia, and Psittacine Beak and Feather Disease, have all been known to cause feather picking. In many cases, these diseases have already been ruled out during a well-bird check. If this is not the case, then I must request that these tests be performed as well. All are diagnosed through obtaining a blood sample.

Bacterial infections, such as Klebsiella and Pasteurella, are also responsible in many cases for feather picking. These are usually diagnosed by performing a culture and sensitivity of cloaca and mouth.

Candida (yeast). This is an organism which is normally found in a parrot's body, but in high populations can also be responsible for a parrot's "itchy" feeling and feather abusive behaviors. Candida is usually diagnosed by performing a gram stain. I often suspect a Candida problem when I obtain dietary information and see that a parrot (often a macaw) is eating lots of fruit, as well as sharing liberally in the owner's sugary snacks.

*** It must be understood that the above is considered a "starting place" only. There are many other physical causes for feather abusive behaviors, which can only be ruled out by further veterinary testing. However, they do occur less frequently it seems than those listed above.

Then, as the above testing is being completed, a history is taken to help discover any information which might point to other possible causes, including those of a "behavioral" nature. The age of a bird might point to increased hormonal activity, sometimes a cause or aggravation of feather picking...especially in cockatoos. The timing of a molt and the severity can be a contributory cause. Dietary information can point to either nutritional deficiencies or food allergies. Environmental information on a history form can point to problems with air-borne toxins, another cause. (I had a case with one macaw who began picking after spending a day traveling with her owner, hiding under the seat of the car near the floorboards of this older vehicle, inhaling engine fumes.) Information about the social climate of the household and the mental attitude of it's inhabitants, as well as certain aspects of the physical environment, can point to "behavioral" causes. Sometimes, the information collected points to another, lesser known, physical cause and the client is sent back to the vet for further testing at that point.

There are many, many reasons for feather abusive disorders and I don't believe we have uncovered them all yet. Each case presents a bit of a mystery to be unraveled. It is important to be as systematic and scientific about this "unraveling" process as a detective would be in a murder case. And, just as in a murder case, it is important to continue collecting "clues", and to be persistent in looking for the cause. Parrots do not abuse their feathers for "no reason." As each possible cause is ruled out, it sometimes becomes necessary to return to a veterinarian for further in-depth testing, over and above what is described here.

At the same time, even while the cause is still to be determined, it is always appropriate to implement changes in a parrot's diet, environment, and care practices which might contribute to some improvement or at least slow down the feather chewing. In some cases, such as those where high numbers of bacteria or fungi are living on the surface of the skin, increased bathing can be of help. Improving the diet will help a parrot who might not be feeling well, will relieve nutritional deficiencies and will enhance the immune system. Eliminating dietary items that can cause food allergies, such as peanuts, will often improve the condition. The elimination of recently-purchased big screen televisions or the recently-installed tract lighting may or may not cause a full recovery. Often, it is necessary to implement solutions and await signs of improvement in order to fully rule out a possible dietary or environmental cause. In the meantime, the provision of lots of "shreddable" items in the cage can sometimes at least slow things down.

I must conclude this by saying that the above can only be considered to be a partial commentary on the need to perform veterinary testing, and of the physical causes which should be ruled out. I am not a vet, nor do I have any veterinary background. I am learning more each day, like everyone on this list, and by no means have the definitive answers about feather picking. However, I look forward to learning more and sharing this with all of you. If each of us is persistent about discovering and ruling out possible causes, and sharing this information, we can someday make a significant dent in this growing problem.


Home Articles Behavior Consultants Case Studies FAQs Links List Information Nutrition Picker's Delight Plucky Stars Toys What's New


 Hit Counter

Last Update:  01/28/01