Re: Big bone vs small bone

[Tivers@aol.com]

In a message dated 98-06-25 19:05:37 EDT, CMKSAGEHIL@aol.com writes:

<< You make some good points, Nicco.  The other variable that is not
considered
 here, and has to be looked at physiologically rather than physically is the
 horse's own metabolic ability to remodel bone in response to stress and
 produce stronger bone.  While to some degree, smaller bone tends to be
denser,
 a lot of this work involved looking at draft horse bone, which is really HUGE
 bone, >but is on horses that have never had to adapt to speed and hence have
 had no selective pressure (from humans or otherwise) to build more dense
bone.>

My work involved private observations of some 350 TB and QH weanlings,
yearlings, racehorses, mares and stallions, using the NIBBS system developed
by George Pratt and EQB. We observed the babies weekly as they went through a
variety of conditioning protocols. The more quickly a youngster responded to
exercise strains, the more trouble he encountered, because the remodeling
process temporarily (2-3 weeks) weakens the bone. 

 Also, as the remodeling occurs, the bone DOES become larger--have seen my own
 horses increase anywhere from 1/2" to 3/4" in cannon circumference over a few
 years of conditioning and competing.  Intuitively I don't think it is
becoming
 weaker because it is becoming larger. >

Your intuition is incorrect. Bone density can decrease as much as 30% during
the remodeling process.


 >Old horsemen talk about bone
 "quality"--that is a pretty ambiguous term, but seems like skilled,
 experienced folks could almost "see" the difference between "good" bone and
 "poor" bone.  I see it more as a matter of tendon and ligament quality, but
 there is a "look" that does seem to be less prone to breaking.>

Racehorse trainers are always looking for big bone that is not coarse. That's
a mistake. They should be looking for 4 meatballs on toothpicks.
 
 >Another interesting note--this is not at all scientific, but in looking at
 photos of older Thoroughbreds and in looking at several of the premier
 stallions in Kentucky, I get the impression that 1) Thoroughbreds as a breed
 have less bone than they do now, that 2) the really class horses have more
 bone than the population at large, and that 3) an appreciable number of
 racehorses still break down, despite (or because of?) less bone.>

Larger horses tend to win more races, mainly because of stride length, but big
bone is fragile bone and you have to take a lot of extra time to bring these
guys safely to the races.

>  Granted,
 many of these went to the track too soon in their conditioning programs or
 were run in the face of pending injuries, but how much did the lack of bone
 contribute?>

The lack of bone density--probably a lot. The lack of bone size is an
advantage.

>  One of the most beautiful and balanced horses conformationally
 that I have seen of ANY breed is a Thoroughbred stallion named Woodman.  He
is
 a pretty damned good sire, I understand.  He has bone galore.  To me it is no
 surprise that he is noteworthy in his sport--I think he could have been
 noteworthy in other sports, too, had he had the opportunity.>

What dose "bone galore" mean? 
 
> As a generality, though, your points are well taken.>

Very well taken.

ti
 
 Heidi
  >>