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A little lesson in
Genetics...
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.)
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.)
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:
 | Red collar puppy
has a hernia. (definately HH) |
| Blue collar
puppy has no hernia. (Hh
or hh ?) |
| Green collar
puppy has no hernia. (Hh
or
hh ?) |
| Orange collar
puppy 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. |
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.
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.
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... :-)
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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