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Ed said:

> If the TB industry really wanted to produce faster horses it
> would open up races to any equine.. Then there would at least
> be a possibility of producing a faster horse by outcrossing.
> Of course this will not happen. There is much too much
> tradition and money invested in the present system.
Actually, the international governing body of TB breeding frequently
discusses the possibility of opening up the stud book because it is well
aware that they may well have reached the limitations of the rather
small gene pool available in "purebred" thoroughbreds.  And it is
interesting to note that improvements in TB racing speeds dropped off
dramatically when the stud book was closed (which most people don't know
was actually quite recently, it IS a 20th century occurrence).  And
since then (especially in dogs), breeders have been using inbreeding as
an attempt at cloning.

Closing of stud books is almost entirely a Victorian concept.  Up until
then a "pure" horse of any breed was one that met the standard of
performance. So, to the bedouin a "pure" Arabian was any horse that
proved itself to be a good warhorse, a "pure" Thoroughbred was any horse
that proved itself to be a good race horse, and a "pure" Standardbred
was any horse that could trot the mile in the set standard time (hence
the name)...and as the horses improved the standard was made faster and
faster.

There are a few breeds today (most notably european warmbloods) that
still use performance ability as a standard for breeding and registering
horses, and one can certainly see VAST performance improvement in pretty
much all the warmblood breeds in the 20th century.

Personally, I think it is past time that the Victorian concept of closed
studbooks was abandoned, and studbooks went back to the original intent
of the Weatherby's General Stud Book, was to keep track of the pedigree
and performance of what breeders were doing with race horses so that it
could be more reliably determined which crosses (that were entirely at
the discretion of the breeder) were most successful...and let the race
track determine whose breeding decisions were right.  From the 17th
through the 19th centuries, that produced an absolutely magnificent
racing athlete that outcrossers around the world are still using to
"improve" their own performance horses a century later.

And right now, the warmblood breeders are trying to recreate the english
thoroughbred (that isn't quite so singleminded about racing as the
modern thoroughbred) by "lightening up" their "breeds" to make them more
suitable as saddle mounts (instead of cart horses, which is a big part
of their "origin").  And it is also interesting to me to note that they
are doing it in much the same way that thoroughbred breeders of a couple
of centuries ago did to lighten up their horses....introducing horses of
"Arabian" breeding.

However, to be able to do this, there also has to be breeders of
Arabians (or any other inbred horse, which, by definition, any horse
from a closed stud book is inbred) to be able to go to for stock to
outcross.

I couldn't breed my Anglo-Arabs by breeding an Arabian to a Thoroughbred
if there weren't people out there breeding Arabians and Thoroughbreds,
despite the fact that an Anglo-Arab is a better horse than both of them
:).

However, from a genetic theory standpoint, if I want my cross breeding
improvement to "stick" (i.e. to breed on to future generations), I need
to breed them back to more closely bred individuals, or I am going to
end up with progeny that have absolutely NO consistency in their
ability.  If I contiue to outcross, I am going to have to cull out a LOT
of horses that aren't "improvements." Just as, if I wanted to "breed" a
better tasting apple by doing sexual reproduction of apples instead of
grafting/cloning, I am going to have to produce a lot of apples that
probably don't taste very good; however, the original Granny Smith was
an "outcross" (an outcross of the Pippin if I remember correctly)

And, BTW, if you analyze Cash's pedigree, which for a "purebred" Arabian
is also quite a bit of an outcross; he too is going to produce a lot of
culls unless he is bred back to horses that are more closely related to
one or the other of his parents.  From a breeding theory standpoint, the
expensive part of using Cash to breed better endurance horses has just
begun, since the next step is to breed the clone to lots of mares, raise
the resultant foals to endurance racing age and then discard the ones
(which will be most of them) that don't measure up.  And it is
worthwhile to note that Cash came by his name because he was sold for a
paltry sum at a rather advanced age (from a breeding standpoint), likely
because he did not show his promise until he was quite old (from a
breeding standpoint).  This suggests that, if his foals resemble him at
all, that the breeders of those foals will have to wait quite a while
before they find out whether they have one that is as good as (or better
than) Cash, so they can't cull them out too quickly or they risk
discarding an exceptionally good one for a paltry sum...the way the
"father" was.  As I said, the expensive part has only just begun, since
breeders who use him as a stallion are going to have to raise alot of
foals to the age of 10 before they know which ones were the right ones
to have produced.

kat
Orange County, Calif.



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