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Fatty Liver
Degeneration
How Inadequate
Diet & Lack of Exercise Can Kill Our Birds
By Judy H. McElveen
It is a recognized fact that
all-seed diets, which are not only high in fat, but deficient in many essential
nutrients, predispose psittacine birds to fatty liver degeneration. It would
seem that the prevalence of this condition in all companion birds, including
cockatiels, would be decreasing since the advent of pelleted diets, but this
does not appear to be happening. Is this because we cockatiel breeders do not
recognize this condition when it appears and kills our birds? Is it because we
don’t know enough about what causes the disease? Is it because we don’t
generally recognize the benefits of pellets? Is it because, in our pursuit of
"substance" in show birds, we don’t differentiate between a bird with a large
frame and one that is fat?
In this article, I will share some
research I’ve done into this health problem. My source is AVIAN MEDICINE:
Principles and Applications, by Ritchie, Harrison and Harrison. When
quotes from this tome appear, they will be "italicized and appear within
quotation marks, like this". This research was prompted by the diagnosis of
fatty liver syndrome in two of my breeding birds and their eventual death. Both
these birds had been bred by (different) prominent breeders and had been in my
possession no more than a year when they died. Also, I have wondered for a long
time if all our show judges could tell the difference, just by looking, between
a bird of true "substance" and one that is simply fat. If they can – great! If
they can’t reliably do so, then our own show standards have probably been
contributing to this health problem. I understand that ACS’s judging emphasis
has now been shifted to length. This is a change for the better, as a long,
well-proportioned bird is less likely to be fat than a bird selected largely on
the basis of "substance".
The main symptom that brought the
problem to my attention was a substantial decline in weight, although I did not
notice a change in eating habits. As all my birds are kept in large flights when
not breeding, I did not notice this until I removed the birds from the flight in
order to set them up for breeding. (Foods present in the flight cages are:
pellets at all times, seed three times a week, and cooked grain and vegetable
"soft food" 3 times a week.) At that time, their weight loss led me to take them
to the doctor, where blood tests revealed liver problems. Although I did
medicate both birds, and tried very hard to get them to eat a healthier diet in
order to possibly reverse the course of this disease, they both died within two
months of diagnosis. Necropsy did confirm the cause of death as fatty
degeneration and failure of the liver.
At this point, I got alarmed about
the possibility that my best breeding cockatiel, Dolly, (a 1996 hatched bird
that is a Grand Champion in both ACS and NCS) who weighs about 200 grams at her
peak weight and when "resting" and between 160 and 175 grams when raising young,
might be in danger of developing this problem. I asked my vet to do blood tests
in order to check out lipid (fat) levels in Dolly’s blood and also liver
function. Fortunately, all these were within normal limits. This does not mean
that Dolly is home free, though, as my vet informed me that, by the time tests
show its presence, fatty liver degeneration is generally irreversible. This
bird, however, was hatched in my aviary and learned to like her pellets and soft
food when she was weaning, so I am optimistic about her healthy future.
"In zoological collections,
Psittaciformes show a high prevalence of fatty infiltration of the liver.
Hepatic steatosis, hepatic lipidosis and fatty degeneration have all been used
to describe the condition. It has been well established that an unbalanced diet
(biotin, choline and methionine deficiencies) or excessive consumption of
high-energy diets with restricted exercise may lead to fatty degeneration.
In other words, a diet that is high in fat and low in essential nutrients, as
all-seed diets are, may lead to fatty degeneration of the liver.
Regarding treatment of the problem,
…"the single most important treatment seems to be the administration of a
well balanced diet free of hepatoxins. Moldy foods and seed-based diets…should
be avoided. The use of lactulose, hemicellulose and supportive care including IV
fluids and assisted feeding are indicated…"
Just eliminating all sources of fat
from the diet won’t do the job, either, as our birds need, indeed require, the
essential fatty acids, linoleic and arachidonic acid. "Deficiencies of
linoleic acid may be associated with decreased metabolic efficiency, decreased
growth, …increased fat storage, decreased reproduction, embryonic mortality and
decreased hatchability…In addition to fatty liver, excessive levels of fat in
the diet are known to cause obesity, diarrhea and oily feather texture, and to
interfere with the absorption of other nutrients such as calcium. Paradoxically,
lack of fatty acids can also result in fatty liver infiltration because
essential fatty acids are needed for lipid metabolism. Poor growth and reduced
resistance to disease also occur with essential fatty acid deficiencies… If fats
become rancid, essential fatty acids may be destroyed, amino acid availability
may be reduced and peroxidases may be produced that interfere with the
activities of fat and water soluble vitamins (biotin). Rancid foods have been
shown to reduce growth and egg production in poultry….Soybean oil is a good
source of fatty acids that is less likely to spoil"….Adequate levels of choline
chloride have been found to help protect Anseriformes (ducks) from fatty liver
infiltration of the liver".
Are we confused enough yet about how
to provide a diet that won’t lead to fatty liver in our cockatiels and yet will
provide the necessary nutrients for proper growth and reproduction? The obvious
answer, to me, is that we cannot possibly supply the necessary nutrients, in the
proper balance so that all can be utilized within our birds’ bodies, in an
all-seed diet, even with vitamin, mineral and or other supplementation. Also,
some supplements used by some breeders, such as "Calf Manna", a milk replacement
product for calves, and/or poultry feed products, contain much too high a level
of some nutrients, to the point where they can adversely affect the health of
our cockatiels. A formulated product, designed by a scientific process to be
properly balanced, can make our jobs as breeders much easier and result in
better health in our birds. We cockatiel breeders are lucky, in that Tom
Roudybush, while at the University of California at Davis, did actual
experiments and long-term feeding trials with cockatiels, so our favorite birds’
dietary requirements have been established with reasonable certainty. Many
pellet manufacturers are also conducting long term feeding trials so that their
product can be adjusted until it is just right. All in all, I think it just
makes sense to feed pellets especially designed for our companion birds.
If you think your birds won’t eat
pellets, you are wrong. I’ve tried all different ways to convert birds to
pellets and the one that has worked the best is this:
Give pellets and other healthy food
such as vegetables and other "soft food" in the morning. Put a dish with the
usual quantity of your birds’ favorite seeds in their cage for a two-hour period
of time in the late afternoon or evening. Believe me, your cockatiels can eat
enough seeds in 2 hours to keep them alive. They will eventually get tired of
being hungry all day, though, and will begin to eat their pellets. When you see
that happen, cut the time the seed is in the cage to one hour for a couple of
weeks, then one-half hour for a couple of weeks, etc. Within six weeks, you
could eliminate seed entirely or just limit seed to two days on the weekends, or
3 days, or whatever you think provides the proper balance. I do believe that
cockatiels need some seed, but do use a seed mixture fortified with vitamins and
minerals, etc. and make sure they eat it all before they get more. When they
only get seed three days a week, believe me, they eat every little grain and
pellet! Make sure fresh water is always available. This is even more important
for birds on a pelleted diet, as pellets have a much lower moisture content than
seeds.
Your birds will feel better with a
better diet – and so will you!
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