Re: [RC] The Great Vitamin Debate--attn. Susan - Susan E. Garlinghouse, DVM
Ok, so Susan what is your stand on
supplementing daily vitamins then?
I agree with Heidi's earlier comments, that
there's no way of really knowing exactly what is going on without having the
forage analyzed, and then balanced accordingly. For most horses, on the
diet you described (high quality orchard grass, beet pulp, pasture and Se
supplementation), I would think you're probably fine without additional
vitamins. At least, you're certainly not "abusing" your horse by not
also supplying a vitamin-mineral mix.
However, like humans, there's a wide variety of
requirements and optimal level of nutrients for horses. More so if the
horse is working at a higher level (whether that be exercise, growth,
reproduction or whatever). Keep in mind we also don't even know what
constitutes "optimal" for horses---the NRC is a distillation of the current
knowledge in 1989, but hasn't been updated, and it definitely has its
limitations. Some nutrients have been better defined since via clinical
research, but not all.
Anyway, the point here is that we have an idea
that some nutrients are beneficial if supplemented beyond what's in a normal
ration (ie, biotin, vitamin e, etc). But we don't know everything about
what nutrients should be supplemented precisely to what level, so *your*
horses exact perfect ration is still guesswork. If you choose to add a
general vitamin-mineral supplement, then to some extent, you're using a
shotgun approach to hopefully fill in existing holes in the ration that may or
may not really represent a true deficiency for the horse. Does it do any
harm? Nah, very rarely if it's not overdone (ie, don't add five doses in
the hopes that more is better). Will it help? Might, if true
deficiencies do exist. Is it a waste of money? Usually not if you
don't go crazy with it. Frankly, the best "supplement" you can provide
is good green grass. Beats anything you can get at the feed store hands
down.
My suggestion would be to look for any problems
in your horses indicative of a nutrition problem---performance issues like
tying up or thumps, poor hoof/hair quality, poor body condition, chronic colic
issues (including enteroliths, rare outside the SW, but a big deal around
here), developmental orthopedic problems in youngsters including contracted
tendons and/or insulin-resistance issues (which, contrary to opinions of the
more excitable ridecampers, I am very aware of).
If you see potential problems in your horses,
then explore whether it might be nutritionally based and investigate it
further---maybe with a general vitamin-mineral supplement, maybe with
adjustment to a few very specific nutrients, maybe with elimination of a
problem feedstuff.
I realize this answer seems pretty ambiguous, but
there really are very few hard and fast rules in nutrition (with the possible
exception of Supplement with Selenium in the Northwest) :-). Look for
problems that might suggest a nutrition problem, and go from
there.