Re: Re: Oregon Hay

["Heidi Smith" <heidi@sagehillcmk.com>]

> Any forage grown in the PNW is almost certainly going to be deficient in
> selenium, so supplement accordingly.  About a milligram a day is about
right
> for most horses, more if they're conditioning hard and/or you're seeing
> signs of otherwise unexplained tying-up/muscle stiffness not related to
just
> a hard workout or riding without warming up first.

Numbers that we got from Oregon State University several years ago indicated
that we should be supplementing as much as 8 to 10 mgs per day of selenium
with our Oregon hay, and having followed several horses with bloodwork (some
for several months to a few years), I'd say that this is more nearly the
level needed when the forage contains virtually none, as is the case with
much of our PNW hay.  Since supplements such as NW and other "high" selenium
supplements only have 2 mgs per daily serving, we accomplished this in the
cases that we supplemented solely by oral supplement by giving EqU-SeE at 3
times the recommended level, which as I recall gave us 7.5 mgs per day.
Most of these horses barely got into the "normal" range on their bloodwork,
and some had to be given injections of E-Se before they would show any
improvement in blood levels at all, although they could be maintained on
oral supplementation once their levels got near normal.  (This led me to
believe that their absorption of selenium was also impaired by the
deficiency, although I have nothing but field experience to back up that
hypothesis.)  Oregon State also at one point had figures out that indicated
that in order to achieve chronic toxicity, the horse had to be ingesting
somewhere in the range of 60 to 90 mgs per day over a fairly lengthy time.
Having seen cattle come up from select areas of Nevada with toxic blood
levels, I know that this can be achieved in nature, but there is very little
danger of selenium toxicity while feeding PNW hay, and good reason to
supplement more liberally than package labels would indicate.

Heidi