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Articles written about the
problem of feather abuse in parrots always seem to begin with a
description of the problem, using adjectives such as
"frustrating,” “disconcerting,” “difficult,” and
“challenging,” among others. Feather abuse or “feather
picking” as it is often called, is a tough problem to solve, and
resolution is frequently elusive.
Further, there is no avian problem as capable of causing
distress to the owner. It
is a painful experience to watch a beloved parrot companion
destroy his own feathers. Resolution of any feather picking case requires that a
methodical and thorough approach be taken to the identification
and correction of all contributing causes.
Owners often look for the cause for the feather abuse.
In reality, there are usually a few factors or problems
that contribute to the behavior in any given case.
The instances of feather abuse in which there is only one
cause are in the minority. They
include those in which one disease-related cause, such as Giardia,
is present and treatment effects a complete resolution of the
problem. At the other
end of the spectrum are those cases in which the young bird has
had a poor early start to life and now lives in a home wherein
enough stress exists to finally push him into abusing his own
feathers.
In the vast majority of
cases, however, a combination of causes is at work.
Poor nutrition is frequently implicated.
Chronic bacterial or fungal infection, such as
Aspergillosis or Candida, is often present and has gone
undetected. Metal
toxicity may be present. Other
contributing factors include environmental toxins, infrequent
bathing, stress and anxiety, hormonal fluctuations, bacterial or
fungal infections of the skin and/or feathers, reactions to
specific foods, and more. This
is one of the reasons why many cases of feather abuse are never
corrected. If we look for just one cause, we run the risk of leaving
undiscovered the other partial causes that are also contributing
to the problem.
Historically, the avian
veterinary community has believed that most feather picking is
“behavioral.” This
term is used to imply that the bird is pre-disposed to picking by
virtue of his “neurotic” or “nervous” personality.
Obviously, such a conviction on the part of a veterinarian
will lead to a minimal level of testing in order to identify
possible physical causes before the “diagnosis” is made that
the problem is a behavioral one.
Only within the past several years have some of the most
progressive avian vets in the country begun to take a closer look
at the possible physical causes for feather picking and to give
these more credibility. Tammy
Jenkins, DVM estimates that approximately 80% of feather picking
cases have at least one underlying physical cause.
Thus, as she and her colleagues look more closely at such
physical causes, our knowledge of them is growing more rapidly.
Accordingly, resolution of
any feather picking case must begin with a thorough veterinary examination.
Just as necessary, is that the owner take an active
interest in learning which tests are performed and what possible
causes they are designed to rule out.
One of the first things I do, as a behavior consultant,
when taking a feather picking case is to request that the
veterinary records be faxed to me so that I can review them.
Every single client who has had a veterinary work-up prior
to calling me has reported the same thing to me, almost to a word:
“The vet has done all
the tests, and the bird is healthy.
It must be ‘behavioral’.”
However, what I have learned from reviewing many sets of
records is that (1) never
have all the tests been done, and further (2) veterinarians differ
widely in terms of the amount of testing and types of testing they
do before pronouncing a problem to be “behavioral.”
The veterinary records
from five different cases on which I have worked within the last
year will illustrate my point.
Below are listed the species of parrot and the testing
completed.
¨
Green-winged Macaw - avian blood
chemistry panel, complete blood count (CBC), fecal smear for
parasites, culture and sensitivity, thyroid function test.
¨
African Grey - avian blood
chemistry panel, blood tests for Psittacine Beak and Feather
Disease (PBFD), Polyoma Virus and Chlamydia.
¨
Eclectus - avian blood chemistry
panel, CBC, blood test for PBFD, culture and sensitivity, skin and
feather biopsies.
¨
African Grey - avian blood
chemistry panel and CBC.
¨
Cockatoo - blood test for
Chlamydia, culture and sensitivity.
As you can see, the number
and type of tests completed vary greatly among the five cases
above. Yet, at the
completion of the testing listed above, each of these
veterinarians indicated to the owners the opinion that the feather
picking was “behavioral.”
Thus, the well-informed
owner, when hearing this “diagnosis,” will look further by
getting either a second veterinary opinion or contacting a
competent avian behavior consultant who is knowledgeable about the
physical causes of feather picking and can provide some guidance
as to what further testing might be indicated, if any.
Unfortunately, it is often
at this juncture…when the problem is deemed to be
“behavioral”…that medication is prescribed to the parrot.
These medications fall into two categories, those that
target hormonal production and those that target the parrot’s
mental state. Medications
that are routinely given to feather picking parrots for the
regulation of hormone production include human chorionic
gonadotropin (HCG), Lupron, Depo-provera, and progesterone, among
others. Medications given to help a bird that appears to be suffering
anxiety and stress include Prozac, Haldol, and Elavil, among
others.
Frequently, a thorough
history taken from the client will indicate the appropriateness of
further veterinary testing. Another
reason that so many cases of feather abuse are never resolved is
because a thorough history from the client is never compared
against the veterinary testing already completed.
In some cases, the information provided about husbandry
methods does point to the need for further testing.
For example, if corncob bedding has been used for an
extended period and has not been changed daily and the feather
picking bird is an African Grey, testing for Aspergillosis may
well be advisable. Corncob
bedding is a fertile growing medium for the Aspergillus
fungus.
In some cases, a bird’s
behavior when picking and the areas of the body upon which he
feather picks will suggest further testing.
For example, a bird that acts “itchy” and
“agitated,” who interrupts eating and playing with toys to
pull out feathers, or who vocalizes when removing feathers, should
have a Giardia test. Giardia
is an intestinal parasite that appears to be more common among
parrots than has been thought in the past.
Joe and Debbie Arbogast
have, in cooperation with their veterinarian and a reputable
laboratory, been offering a Giardia screening clinic at their
website, www.birdsafe.com,
now for over a year. Their motivation for doing so has come from
their own experiences with feather picking birds that suffered
from giardiasis. Mr.
Arbogast, having recently compiled the figures from the last year,
has found that approximately 18% of feather picking birds tested
through this clinic had positive test results.
This figure is even higher for conures.
Further, since false negative results are common, it would
appear that the incidence might be even higher than these figures
reflect.
It has long been believed
within the veterinary community that larger parrots rarely have
Giardia, although it has been acknowledged for some time now that
approximately 75% of cockatiels carry this parasite. It is also
quite common in budgerigars, lovebirds and Grey-cheeked Parakeets.
Because of Mr. Arbogast’s work, I have become convinced
that any feather picking bird should have a fecal trichrome test,
wherein the owner collects the samples over the course of three
consecutive days.
Once it has been
determined that no further veterinary testing is immediately
warranted, or any indicated testing has been completed, all other
aspects of the parrot’s care must be examined.
If I had to name the second most frequently contributing
cause to feather picking, aside from disease-related reasons, I
would have to say it is diet.
Several aspects of the diet can be implicated in feather
picking cases.
Some birds do react to
certain foods by abusing their feathers.
The species in which I have personally found this to be a
cause for feather abuse include Green-winged, Blue and Gold, and
Scarlet Macaws, Eclectus, parrotlets and African Greys.
Whether these birds are truly experiencing an allergic
reaction, or simply have a hypersensitivity to a particular food,
is unknown. However,
when the offending food is removed from the diet, the problem
improves or resolves completely.
Reactions occur to synthetic food dyes, preservatives,
individual foods themselves, and/or to the “pesticide load”
some foods carry.
In other cases in which
diet is implicated, feather picking may occur due to a shortage or
deficiency of certain nutrients.
A deficiency of enzymes and/or essential fatty acids in the
diet will contribute to feather abuse.
This most often occurs when more than 50% of the diet is
comprised of cooked or manufactured foods in which these nutrients
have been destroyed. Improvement
can be seen when the amount and variety of fresh, live foods are
increased. In some
cases, supplementation with essential fatty acids is beneficial.
Calcium deficiency can play a role in feather picking in
African Greys.
A thorough discussion of
the many ways in which diet can contribute to feather picking is
not within the scope of this article.
For more information, please refer to The
Not-So-Hidden-Link between Diet and Behavior.
I do believe that
“stress” also plays a role in most feather picking cases,
given the fact that our parrots are asked to live a life-style
that is vastly different from the one they would enjoy in the
wild. In this
context, the word “stress” must carry a broad definition.
Both social and environmental factors can contribute to
stress and anxiety in captive parrots, as can a stifled
reproductive drive or a heavy molt in some birds.
Certain social factors can
either cause or contribute to a feather picking problem.
Parrots are creatures to whom the health, both physical and
emotional, of the flock carries great importance.
In captivity, many rather subtle aspects of the "social
climate" can create stress for parrots,
and either contribute to or be the sole cause for feather picking.
The manner in which a
parrot chick is reared can be a predisposing factor to feather
picking in some species. African Greys, for instance, tend to
internalize anxiety. They do not recover emotionally from difficult experiences
the way that Amazons and some of the other New World birds do.
The practices of deprivation weaning wherein a parrot chick
is weaned as early as possible in order to be sold, and clipping
the chick's wings before it has had a chance to fledge and learn
to fly, both contribute to creating a "personality
profile" that is often more likely to feather pick in less
than optimal circumstances later on. Such babies enter life in
captivity at a
disadvantage, with residual anxiety from being hungry, and/or
physical uncertainly from not having attained their true measure
of physical development.
Another social situation, if it occurs early in a parrot's life,
can also be the precipitating event to a feather picking problem.
This happens most often with African Greys, and has become widely
recognized among behavioral consultants as a cause of plucking.
This occurs when the owner goes on vacation during the first year
of a baby Grey's life. I don't think anyone really knows for sure
why this happens so often with Greys and not other species, or why
in the first year and not afterward.
However, there have been many owners who went on vacation
during their baby Grey's first 12 to 18 months, and came home to a
bird with fewer feathers. Greys
seem to need a longer period of time in their new homes to form a
very secure bond before they can psychologically withstand the
stress of their owner's departure.
The manner in which the
owner socialized a young Grey will often determine the likelihood
that the bird will feather pick later due to stress.
Many owners have a tendency to shield their Greys from
anything new or uncomfortable, since these birds have developed a
reputation for being “nervous.”
The impact of this tendency is to prevent the parrot from
developing the skills necessary to deal with new things or
experiences. The
bird’s experience is narrowed to the point where anything out of
the ordinary is capable of causing anxiety that results in the
pulling of feathers.
Another factor that frequently contributes to feather picking has
to do with waiting.
This tends to impact parrots that are anxious in
general, or who do not have good eating skills, and occurs most
frequently in the morning. We often hear the advice that parrots
need 10 to 12 hours of uninterrupted sleep each night. What is not
usually mentioned is that they also have a need to get up early.
Most parrots, even if covered, will still wake up as soon as some
light creeps under their cage covers.
If the owner needs to sleep in, the parrot is often faced
with hours of solitude and hunger as it awaits the opportunity to
be uncovered and fed. Parrots that feather pick often choose these
early morning hours to work on their feathers. In such cases,
every effort must be made to get the parrot up and out of the cage
earlier in the morning and to give him something to eat right
away.
The latter is very
important with any feather picking parrot that was weaned too
early. Anxieties certainly exacerbate picking problems and any
parrot weaned too early or who was deprivation weaned will become
more anxious when hungry. It can help in such cases to make sure
that there is a supply of food available in the cage for that
early morning period before breakfast is served.
Bird rooms can cause problems for some parrots. These have become
quite popular because they allow a family to have several parrots,
and yet confine the mess to one room. Many parrots do well in bird
rooms...but many do not. First,
African Greys are rarely as happy in a bird room as they will be
if located in the family's living area. Greys maintain a close
psychic connection to their human flock and do not like to be
isolated away from the family's goings on.
Second, birds that are subject to stress can have problems in a
bird room if there are too many parrots in the room. Having the
cages closer together than five or six feet can result in
additional stress for an already anxious parrot.
Some parrots will psychologically harass others out of a
sense of territoriality. I
realize that this sounds unlikely, but it occurs quite often.
Parrots can take a dislike to one another the same way that humans
can. Being forced to
live in one room with more than a comfortable number of other
parrots may result or contribute to feather picking.
Another factor in some feather picking cases is the emotional
"make-up" of the owner, or the social climate of the
home. Some feather picking parrots are merely the "symptom
bearers" of an unhappy household or a neurotic individual.
Excessive animosity, ongoing tension or frequent arguing will all
create stress for a parrot who intuitively senses that something
is wrong.
We must remember that parrots are extremely social, flock oriented
creatures. In the wild, separation from the flock, or problems
with flock members, can spell death for a parrot. Instinctively
they know this, whether they are still in the wild or living in
our homes. Thus, tension in the household, if it goes on too long,
will put a parrot psychologically on "red alert."
Similarly, a single owner that is chronically stressed, unhappy,
or tense conveys a message to a parrot that is similarly
interpreted as, "Something is wrong here and it might mean
that I'm in danger!" I once had a client with a feather
picking Grey who confided to me that she has never felt safe in
the world. Having come from abusive circumstances, she had good
reason to feel this way. However, this fear had taken over to the
point where she felt constantly in danger and reacted to the
slightest change in routine with increased anxiety. Her constant
state of anxiety was creating problems for her African Grey.
Some parrots suffer from separation anxiety and will do most of
their feather picking during the first 30 minutes after the owner
leaves for work. In such cases, it can sometimes help to give the
bird a shower just prior to the owner's departure.
This helps to take the bird’s mind off of the emptiness
of the house and onto fixing his feathers.
Once feather picking starts, the owner's reaction to the onset can
be deleterious. It is understandable that the owner would become
upset, but this must be dealt with in a productive way. Some
people give their parrots attention when they observe them
picking, in a misguided attempt to stop the behavior.
If the parrot interprets this attention as a reward, the
picking behavior can actually be strengthened and reinforced,
particularly if the bird is hungry for attention.
Other owners almost completely change their behavior toward the
parrot that starts to pick. A vicious cycle develops in these
cases. The bird starts to feather pick a little, and the owner
gets upset enough that she changes her behavior toward the bird.
This frightens and stresses the bird even more and he picks more.
This causes further behavioral changes in the owner, which causes
more plucking.
In still other cases, the
owner is not only upset about the problem, but focuses so much
attention on the parrot and this problem behavior that the bird's
feather picking is actually made worse.
Many owners will count the number of feathers pulled each
day, or store them in a jar. They constantly watch the bird in order to try to prevent the
behavior. In the
wild, parrots do not place such an intense focus upon each other.
It is only predators that focus this intently upon their
prey, waiting for the perfect moment to strike.
Since parrots are still largely instinctive creatures, this
type of intensity on the owner’s part can increase the
parrot’s anxiety. Owners are always well advised to take a more relaxed
approach to the problem. It is normal to feel stress over the
problem, but try to banish this when interacting with the parrot
and do not count feathers.
Environmental factors
often play a role in the creation or the resolution of a feather
picking problem. These include cage placement and location,
frequency of bathing, substances that get on the feathers
themselves, inhaled toxins, ingested metals, and full spectrum
lighting.
The location of the cage
can have a huge impact upon a parrot’s sense of security.
If the cage is in front of a window, this can afford the
bird a profound sense of vulnerability.
Parrots, if alone in the wild, do not normally perch in a
location where they are highly visible.
In order to feel secure, parrots need the conviction, the
absolute knowledge, of physical and psychological safety. Often a
parrot will live quite happily in front of a window until the day
that a juvenile hawk perches outside staring at him, or a wild
bird slams into the window, and from that day forward the window
itself is perceived as a threatening aspect of the environment. In
such cases, it can help to shift the cage slightly to the side, so
that only half of the cage is in front of the window, and a wall
shields the other half. That way, the bird has a choice and
can move from a place of exposure to a place of
"hiding."
New additions or changes
to the physical environment can create enough stress for a parrot
that feather picking begins or increases. The installation of
overhead track lighting, large screen televisions, large
aquariums, and large pictures or fabrics hung on walls hear their
cage have all been implicated in cases of feather abuse.
Foreign substances that
get on a parrot’s feathers can instigate plucking.
Feathers are critical to a parrot's survival - they are
sensitive about the health of their feathers.
Behavior consultant Sally Blanchard often describes a case
that involved a feather plucking cockatoo. This bird and his owner
sat together every day watching television.
The owner usually ate potato chips as he did so. He would
have a chip, and pet his bird...have a chip, and pet his
bird...have a chip, and pet his bird. The resulting load of grease
on the bird's feathers caused him to remove them in a frantic
attempt to "clean" himself.
In yet another case, an
African Grey was brought into the shower each day and placed on
the floor of the cubicle while the owner shampooed and soaped
herself. After she rinsed herself off, she would also spray him
lightly. Just enough
of the soap products were staying on his feathers to cause him to
begin to pick on his back. Anything that gets on the feathers,
including nicotine from the hands of a smoker, can be an
instigating factor in feather abusive behavior.
Frequent hand washing is a good practice to get into if you
are frequently handling your parrots.
Brian Speer, DVM, agrees
that lotions and other substances on an owner's hands can be the
cause of feather picking.
(He has suggested that owners dip their hands in cornstarch
before petting any "powder" birds they might have, such
as cockatoos, Greys, and cockatiels.) One of his ongoing concerns
is that such substances will actually cause fungal growth on the feathers - not just on the skin - and that this can cause a
real inducement to feather picking. He often prescribes a
medicated shampoo, Pyoben, which contains 3% benzoyl peroxide and
has antimicrobial, keratolytic and follicular-flushing properties.
Inhaled toxins or other
substances can contribute to feather abuse.
Parrots have very sensitive, delicate respiratory systems
that cannot deal with many of the airborne substances routine to
life in captivity. Smoke, either cigarette or marijuana smoke,
will contribute to and/or be the sole cause of feather picking.
The presence of smoke can either cause a problem directly, or can
so damage the air sacs that the parrot succumbs to a chronic
infection of the air sacs such as aspergillosis.
A few parrots have even been reported to react with
plucking to the smell of smoke on a human’s clothing.
It is believed that some
of the powdered products sold for freshening carpeting, air
fresheners, scented candles and similar products with a strong
odor can also be contributory to feather picking.
To date, I remain unaware of any instances in which the
correlation between such substances and a feather picking problem
has been proven, although anecdotal information is quite
persuasive. It makes good sense to eliminate the use of these if
you have a parrot that plucks or chews his feathers.
Carbon monoxide in the
environment has caused feather picking. Behavior consultant Liz
Wilson once discussed while lecturing a case in which a pair of
macaws housed indoors feather plucked themselves to the point of
nakedness. The cause remained a mystery until it was discovered
that they were housed in a room located over the garage. Just
enough carbon monoxide was making its way upward into the house
that the macaws were adversely affected.
Airborne dust from other
species of birds can be a problem for some macaws, which are
housed in the same enclosed space as cockatoos.
The presence of other “powder” birds, such as Greys and
cockatiels, could also be a problem, but it appears that most
problems occur when cockatoos and macaws are roommates.
Lack of sleep can
contribute to a feather picking problem. I live with a diverse
population of parrots, and species do differ in terms of the
number of hours of sleep needed.
Generally speaking, Central and South American parrots are
happiest when getting a full 10 to 12 hours of darkness and
uninterrupted rest. African
Greys, once mature, frequently need fewer hours of sleep than
this. This is
substantiated by the fact that they have been observed in the wild
flying well after darkness has settled.
Some cockatoo species, among them the Goffin’s, do better
if allowed to stay awake longer in the evenings.
High zinc or lead levels
in the bloodstream have been recognized as causing feather abusive
behavior. These
metals enter the parrot’s digestive tract when the bird mouths
certain items. Most
of the cases of metal toxicity of which I hear concern cockatoos,
who are exceptionally “beaky” birds by nature and are often
fascinated by metal objects.
Zinc is present in many
forms in the parrot’s environment. Many of the fasteners used to
hold toys to the cage are galvanized metal, which is coated with
zinc. Bells on toys
can contain zinc. The
powder coating on some of the less expensive cages has been shown
to contain zinc. One feather picking Umbrella Cockatoo who
exhibited very high levels of zinc in his blood had a habit of
drinking from the bathroom faucet.
While doing so, he would scrape the inside of the fixture
with his beak.
The most frequently cited
sources for lead toxicity include the leading on stained glass
windows and other items. This
is quite soft and readily yields to the pressure of a curious
beak. The small seed
beads used to make jewelry often contain lead. Some parrots have increased levels of lead from ingesting the
weights that are placed in the bottom hem of draperies.
Some feather picking
problems appear to have been improved by the provision of full
spectrum lighting or an outdoor aviary.
It is unclear at this point as to why such improvement
occurs. Possibilities
include better absorption of calcium due to higher levels of
vitamin D3, or simply the stimulation provided by better lighting.
Although I do not see this
as frequently as I do other causes, there are times with certain
individuals when feather picking will be associated with either a
heavy molt or hormonal fluctuations. I've seen this especially
with Goffin's Cockatoos, but it also occurs with other species as
well. It should not be too difficult to determine whether the
feather picking your bird is doing is associated with a molt or
hormonal surges.
For one thing, timing is important. Most parrots will molt prior
to breeding. If your bird is feather picking due to a molt, you
should see the picking decrease once the molt is completed and all
new feathers have lost their sheaths. In addition, it most likely
will not occur again with the next molt. When feather picking does
occur due to a molt, this often is an isolated instance. It may be
the parrot's first molt, or an especially hard molt, which leaves
him more uncomfortable than usual. Rarely, however, will the same
parrot engage in feather picking every time he molts.
Some parrots engage in
feather abuse during especially hormonal periods.
With some species, these are signaled by increased
aggression and noise as well. In order to determine whether
hormonal fluctuations are a factor in a parrot’s plucking, it
can help to keep a diary of feather picking behavior. Unlike
picking that may occur due to a heavy molt, hormonally related
feather picking will usually occur in a cyclic fashion every year
when breeding season arrives.
The parrot often then returns to a completely feathered
state once breeding season has ended.
As was mentioned above,
veterinarians will frequently suggest medication for a feather
picking parrot, especially when hormonal reasons are suspected as
the cause. In some
cases, it has been suggested to the owner that they should either
place their parrot in a breeding situation, or resort to such
medication, neither of which is advisable in my opinion.
Avian Medicine:
Principles and Application
by Ritchie, Harrison and Harrison reports:
"Occasionally, a bird will self-mutilate as a result
of sexual frustration. Some of these birds will stop mutilating
when placed in a breeding situation; however, others will continue
self-mutilation activities and may also over-preen a mate.
Assuming that idiopathic self-mutilation is a result of some
undetectable neurosis, it would be considered unwise for these
birds to be added to a breeding collection where they may pass on
genes that will predispose their progeny to the same
problem." (The authors are referring to feather-picking when
using the term "self-mutilation" and are not
specifically referring to episodes wherein the bird bloodies
himself.)
Regarding medications for
this problem, the authors go on to say, "...Mood-altering
drugs that have been suggested for use in feather-picking birds
include tricyclic antidepressants and antihistamines.... These
therapeutic agents are frequently discussed but are rarely
effective. Hormonal therapies including thyroxine, testosterone
and medroxyprogesterone have also been
suggested for some cases of feather-picking; however, all of these
agents have undesirable side-effects and should be used only to
treat specifically identified problems."
In his discussion of the
subject in Holistic Care for
Birds, author David McCluggage, DVM writes:
"Western medicine may treat these seasonal pluckers
with hormonal therapies and tranquilizers. Some hormonal therapies
are relatively safe, like chorionic gonadotropin (HCG), while
others are very dangerous, and the progesterone, testosterone, and
estrogen therapies fall into this category. Drugging a bird for an
essentially normal behavior is somewhat troublesome.
Only rarely the use of what we call psychoactive drugs (such as
Prozac) are used for the same reason. Other therapies employed
include a variety of tranquilizers, which have proven ineffective
in my experience."
Working through a thorough
examination of all the possible causes for feather picking in a
given case, and correcting any problems found, can take months.
However, in the majority of cases with which I deal,
patience and persistence pays off and the parrot becomes feathered
again.
This is not the case,
however, in a certain percentage.
However, even then, there are measures that can be taken.
Mr. Arbogast relates his positive personal experience of
treating a feather picking parrot for Giardia, even in the absence
of a positive test result. This
is not an infrequent outcome.
In a certain percentage of cases, treatment through a
veterinarian with metronidazole (brand name Flagyl) causes
resolution of the problem even when serial Giardia tests have
yielded a negative result. It
is never known whether the parrot did in fact have Giardia, or
whether another parasite such as Cryptosporidium was implicated,
or any one of several strains of anaerobic bacteria, all of which
are killed by this medication.
In still other cases, a
strict elimination diet, which identifies any foods to which the
parrot reacts, can prove to be the final action that brings
resolution of the problem.
The cases that often do
not resolve completely are those in which anxiety and/or stress
play a heavy role. Unfortunately,
it is not that easy for humans to change lifelong behavior
patterns, even if they are causing problems for a companion
parrot. However, even
in such cases, improvement is often seen when behavior
modification techniques are employed, the bird is provided with an
outdoor aviary in which to relax and play away from human
influence, and techniques to reduce the bird’s stress are
implemented.
Agnes E. Rupley, DVM. Manual
of Avian Practice
Branson Ritchie, DVM, Greg
Harrison, DVM and Linda R. Harrison.
Avian
Medicine: Principles and Application
David McCluggage, DVM.
Holistic
Care for Birds
Personal communications, Brian Speer, DVM, 2000
Personal communications, Joe Arbogast, 2001
Personal communications,
Tammy Jenkins, DVM, 1999
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