Home Current News News Archive Shop/Advertise Ridecamp Classified Events Learn/AERC
Endurance.Net Home Ridecamp Archives
ridecamp@endurance.net
[Archives Index]   [Date Index]   [Thread Index]   [Author Index]   [Subject Index]

[RC] Selecting for longevity in endurance competition - k s swigart

Ed said:

You could singlemindedly select for horses that could run
100 miles in 24 hours from the time they were 5 until they
had 10,000 miles of competition.  You then, 200 years later,
would have great endurance horses.

Actually, you would have a hard time in actually selecting for the
ability to do 10,000 miles of competition starting when they are 5
specifically, since by the time that you had proven that the horse can
do it (thereby proving its ability for this)...and can throw horses that
do it (therefore proving not only that the horse can do it but that the
trait breeds on), the horse is dead.

One of the essential requirements for "singlemindedly selecting for" a
particular trait is that you must ruthlessly crop out those that do not
exhibit the trait, and you must also ruthlessly crop them out if, even
if the horse does exhibit the trait, its offspring don't.  Consequently,
you it is extremely difficult to select for a trait that doesn't exhibit
itself until after the individual's breeding career is already over.

You would have to find some other way to performance test the
individuals (and its offspring) that you hope is a good proxy for the
ability to do 10,000 miles of competition starting when they are 5.
Some people say that being a war horse in the desert is a good proxy for
this, some people say that the feral lifestyle of the western US is a
good proxy for this, some people say that flat track sprint racing is a
good proxy for this, and some people say that working cattle on the
Rushcreek Ranch is a good proxy for this :).

However, the fact remains, that all these things are but proxies to be
used as selection criteria because the real trait that is being hoped
for would take 30 years of testing to find out which horses you should
have been breeding (before they died :)), especially since so far
virtually all the horses that have successfully proven that they can do
this are.....geldings (i.e. genetic dead ends :)).

It is virtually impossible to "singlemindedly" select for longevity in
endurance competition, instead what breeders must do is select for other
traits that they hope will lead to longevity in endurance competition.

Some of the new reproductive technologies (frozen semen, embryo
transfer, etc.) may extend an individual horse's breeding years to the
extent that it may become easier in the future.  However, in order for
it to be done with any real hope of success, it also has to be done
LOTS.

kat
Orange County, Calif.




=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

Ridecamp is a service of Endurance Net, http://www.endurance.net.
Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp
Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp

Ride Long and Ride Safe!!

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=