Re: RC: Selenium & Vitamin E Supplements

[CMKSAGEHIL@aol.com]

In a message dated Fri, 9 Feb 2001  1:33:26 PM Eastern Standard Time, "guest@endurance.net" <guest@endurance.net> writes:

<< Kathy Bishop jbishop@att.net
I am looking for information on amounts of selenium and vitamin E used
 to treat a horse that has  tied up. What are the min and max amounts that can 
can be given on a daily basis? >>

First of all, you have to determine whether selenium deficiency is actually a part of your horse's tying up complex!  Have you tested his plasma levels of selenium?  Unless you live in a selenium-deficient area where you can pretty much count on your horse being deficient, you'd best test before you do a lot of supplementing.  That said--the daily selenium requirement is in the neighborhood of 8-10 mg per day, and that can vary depending on other trace mineral highs and lows in your area, etc., as some minerals can interact and interfere with absorption of other minerals.  "High selenium" supplements usually contain a maximum of 2 to 2.5 mg per daily serving--so in a deficient area can still be very short of the requirement.   The tricky thing about selenium is that chronic toxicity occurs at 60-90 mg per day--so one doesn't just want to "treat" with it willy-nilly unless one knows that a deficiency exists!  Best suggestion is to test, and then to supplement accordingly--look !
for plasma levels in the neighbo
rhood of 200-250 ppb (sometimes reported as ppm instead, so just move the decimal point over and look for .20-.25 ppm).  Some horses that are extremely deficient actually have difficulty absorbing selenium from the gut, and just about have to have injectable selenium to begin to get their levels up--once up over 150 ppm or so, one can usually maintain and increase using oral supplements alone, in my experience.

Vitamin E is a bit easier as it is not especially toxic.  You can feed 4000-6000 IU a day if need be, and be fine.  In fact, boosting the E supplementation will help with selenium absorption and utilization as well, so you may be able to get by with less selenium supplementation.

JMPO, but I wish selenium levels would be done routinely on tie-up cases, so that one could determine at the outset if selenium is, indeed, part of the problem.  I came from a very deficient area, and moved into a somewhat deficient area, so we can pretty much assume a deficiency in any horse that has not had supplementation.  So--we can just go ahead and give an injection of E-Se to any horse that ties up, and go forward with selenium supplementation.  But unless you have talked to a veterinarian well versed in local nutritional conditions (or you know the approximate levels in hay you may be getting from outside your local area) or to a local extension agent, you are still best to test first.

Heidi