| Hi Jeanne,
Yes, I had a problem with a deficient immune system in a bird.
Intensive vitamin A therapy and weeks of special care turned him
around. He had been fighting a low grade infection so long when
I got him, his immune system was exhausted. With supportive care
he was able to regroup. He had to have antibiotic and anti-fungal
treatment also at first, and nasal flushes to help repair his
mucous membranes to closer to normal elasticity.
I'm not sure this is what happened with your Sunny. I just lost a
beautiful pearl tiel hen to lymphoma (cancer) at the young age of
a year and a half, just as she was about to be set up with a mate,
so I guess they can have most any problem we do. The necropsy
results made me breath easier because it was nothing contagious
(she had no outward signs of illness at any time in her life,
other than looking unusually sleepy the day before she died).
With the pathology available to us today, at least we can make
a distinction between a death due to natural causes or something
we contributed to -- or not -- as well as knowing if there is a danger
to any other birds we have (or to ourselves, for that matter, as in
the case of psittacosis).
On the other half of your questions: Colony breeding is certainly a
time when inbreeding can easily occur, but it is not the only time
there is in-breeding. Some line bred birds are set up this way
deliberately by the breeder, in pairs, in the hope of pulling
forward some desireable trait(s). So a brother and sister might
be put together on purpose, for example.
Line breeding is _usually_ cousins to cousins or uncles to nieces, etc.,
to use the 'human' terms. A portion of each bird's gene pool is 'related'
to the other's gene pool. But siblings are sometimes paired as well.
When siblings are mated, the gene pool is identical in both birds.
Unfortunately, this close breeding using siblings increases the chances
that any flawed genes are combined, as well as the chance that the
desired genes are magnified by this crossing. Some of the resulting chicks
may be severely compromised genetically, while their clutch mates who
carry forward the desireable traits may be show winners.
With more conservative line breeding, there is always a portion of
the gene pool in each individual that is related, and a portion that
is not. This doesn't guarantee that there will never be a chick from
this pairing with genetic defects, but there is much less of a chance
than when siblings are paired.
Many consider that cockatiels with multiple color and marking mutations
have a weaker gene pool than a normal gray tiel. As a breeder and
owner of tiels, I _have_ noticed the normal gray chicks seem to develop
sooner than those that are two or more visual mututations (e.g., cinnamon
pearl pied, lutino pearl, whiteface lutino a/k/a 'albino').
The chicks carrying a recessive gene (called /split to whatever) don't
seem to be any slower developing than a normal gray or a chick with
only one mututation (e.g., visual gray pied/lutino or a visual
cinnamon/pied/whiteface).
Jeanne, thanks for being so good about keeping us informed here as you
have gone through these difficult times with your birds. I imagine it has
not been easy to write some days.
Linda C.
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| I had my English Budgie, Sebastian, died last fall from severe liver
degeneration. He was about 5 years old and had extra-watery droppings
over his last 5 months or so. The vet had run several blood tests
early on and did see evidence of increased bile in the blood serum, but
no sign of infection otherwise. The autopsy didn't give any clues as
to what may have caused the liver problems -- no tumors, parasites,
etc. I have a cockateil about the same age and he seems to be fine
after adjusting to the loss of his buddy, so luckily whatever the cause
of the liver failure, it doesn't seem to be contagious in this case
either.
Laura
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