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A little lesson in Genetics...
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 | Lets use an Umbilical Hernia as an
example. (Umbilical Hernias can be genetically passed on or
could happen
when the dam bites the umbilical cord to short on a newborn puppy, for our
example
here, we'll
assume that
we've only got the genetic kind.)
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 | We've got a sire and dam picked out, neither one of them
has an Umbilical
Hernia, so we should
produce
a litter of puppies that
have no Hernias, right? Ummm... maybe not... |
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Sire
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H
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h
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Dam
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H
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HH
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Hh
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h
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Hh
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hh
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 | Our sire and dam each have two possible genes
to contribute to each puppy. The "H" stands for
the gene
that can produce a hernia. The "h" stands for a clean
gene, one that doesn't produce a
Hernia. |
 | Lets say that we have a litter of four female
puppies. That means that statistically speaking, one
of the dogs will
probably
have a hernia (HH) , two of the others are probably carriers
(Hh) even
though they don't have Hernias themselves and one
of the dogs is probably clean
(hh) and doesn't
even carry the gene that produces the Umbilical
Hernia. But of course of the
three that didn't have
Hernias, we have no clue which was the 'clean'
dog just by looking at them. |
 | Here's how our litter broke down:
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 | Red has
a hernia. (definately HH) |
 | Blue has
no hernia. (Hh
or hh
?) |
 | Green
has no hernia. (Hh
or hh
?) |
 | Orange
has no hernia. (Hh
or hh ?) |
 | Now lets move move on to the next
generation... Each of our four females has been bred to a
wonderful stud dog that we'll
call Brown. Lets assume that this male dog has a
chance of carrying
the gene for Umbilical Hernia, because we know that
one of his
parents had a hernia. (We found
that information in our trusty
little database.) |
 | Here's how the next generation of puppies
turned out:
 | A few of Red's
puppies had hernias. |
 | Two of Blue's
puppies had hernias. |
 | One of Green's
puppies had a hernia. |
 | NONE of Orange's
puppies had hernias. |
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 | So what does this tell us about our original
litter of four dogs, and our sire "Brown"? |
 | It tells us that Yep, we were right, Brown
is indeed a carrier and possesses the recessive gene
for Umbilical Hernias, so
statistically speaking, he can pass that gene on to 75% of
the puppies
he sires.
(So lets update his
entry in the database (Hh)
so anyone else that breeds their female
to Brown will know that information!) |
 | It also tells us that "Orange"
(who has had two other litters previously) is probably not carrying
the gene for Umbilical Hernia (hh). So, if in future generations, we
breed her puppies to mates
that also don't carry the Hernia gene, we
will never see
Umbilical Hernias in Orange's
line again! |
 | It tells us that Blue
and Green
are also carriers for Umbilical Hernia (Hh), so future litters that
are bred to a male
that
has a Hernia, or you will get at least some of
the puppies with Hernias. |
 | It also tells you that if Blue
and Green
are bred to a male that isn't a carrier, that although some
of their
puppies will carry
the gene as a recessive, none of them will actually
have a Hernia! In
subsequent generations of careful breeding, the puppies will not have hernias, and the number of
pups that have
the recessive gene will be 'watered
down' and the genes for Umbilical
Hernia will
eventually be flushed out of the gene pool just like we
showed with
Orange.
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 | But that's
many generations (of careful breeding practices) away. And if
one of these generations
is
mated with a dog that has a Hernia, you're
back where you were, the 'bad' gene is back and
subsequent
litters
from that mating will have to be watched and
controlled accordingly.
This is
where REALLY good database comes in. It also means that
we have to have honest reports from
our breeders, and a commitment
from every one of them that they are willing to work at eradicating
the
diseases that the
group chooses to work on.
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Is this a lot of work? You bet it is!
 | We were only talking about a little bitty
Hernia... If you're talking about things like Hip or Elbow
Displasia, SAS, or a
myriad of other extremely painful, or deadly
diseases, isn't all this work worth
it??? |
 | With careful record keeping, and careful
breeding, we can focus on a few of the worst diseases and
get rid
of
them, once
and for all. Then we can move on to a few of the lesser
diseases and work on
getting rid of them... and so on... and so
on... :-)
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Ok, so to get back to you and your dog...
 | You were asking if you should bother to fill
out the survey... Lets assume that in the litter above,
the owners of Blue,
Green
and Orange
never reported back to their breeder to let him know that
their dog had (or didn't
have!) a problem. It
would leave gaping holes in the
database and it would
make the breeders job of trying to figure out
which dogs were
carrying what genes almost impossible. |
 | Reporting back to your breeder and filling
out our survey is critical for us to be able to breed better
Shilohs. It takes
teamwork and good communication to breed better dogs. :-) |
 | Soooo... since you've gotten this far,
how about going to our Survey page and filling
it out with your
dog's information? Even if your dog is healthy, we
still need the information. And don't forget, if
your dog develops
any diseases in the future, make sure you come back here and enter the
new
information.
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