"For example, Hintz et al. (1971) reported prececal apparent digestibility values of 71
percent for nonstructual carbohydrates in a high-corn diet and 46 percent for those in a
high alfalfa diet. Glucose derived from from this digestion enters the portal vein and
contributes in a major way to the horse's energy budget." H.F. Hintz, D.E. Hogue, E.F.
Walker, Jr., J.E. Lowe and H.F. Schryver. 1971b. Apparent digestion in various segments
of the digestive tract of ponies fed diets with varying roughage-grain ratios.
J.Anim.Sci. 32:245. As reported in NRC's Nutrient Requirement of Horses (1989).
Please note that corn and particularly alfalfa contain a large amount of structural
carbohydrates - these numbers refer to the non structural components. No time frames
are given but I would assume they would not be all that different than in humans which
derive almost all their energy from the small intestine and very little from activity in
the large intestine. Simpler carbohydrates one would assume would be absorbed quite
quickly.
Bottom line: hay should still be fed for purposes of not screwing up the digestive tract
and because of its lower percentage of structural carbs is probably not going to have a
huge impact on energy while competing. But the addition of simple carbs probably would.
What overall effects it has, I await those of you on the cutting edge.
Duncan Fletcher
dfletche@gte.net
Tivers@aol.com wrote:
>
> In a message dated 97-01-02 20:46:59 EST, you write:
>
> << >Truman Prevatt wrote:
> >> One comment I forgot to make was the following. All the equine sports
> vets
> >> I have talked with (Waldorn, Ridgeway, Fraizer, Jon Warren, Ann Stewart)
> >> say the same thing. Food fed now takes 24 to 48 hours to get through the
> >> digestive system and useful as food for the muscles. There is also about
> >> 24 to 36 hours reserve of processed (ready to be used) food in the hine
> gut
> >> of the horse. The energy the horse gets during a ride comes from the
> hine
> >> gut and not what you feed. >>
>
> Not so. Simple carbohydrates will hit the energy system within one hour and
> blood glucose will peak within 2 hours of feeding. Grain feeding will produce
> similar, but lower-peaked glucose curves. All these "experts" who are
> agreeing have never bothered to test the theory, evidently. If you want to
> test it, just go down to the drug store and get a simple glucometer. In five
> hours you can get your horse's response to any kind of feed.
>
> ti