Whole blood analysis is what my vet has done (at
Cornell, except for the time their equipment was on the fritz and it went to
Michigan).
I've never found Se at more than 2mg per
dose. And even that's not nearly enough here (my gelding gets 4mg daily,
in addition to the tiny amount in his grain). When I did my original
search (several years ago), I was amazed at all so-called the "selenium
supplements" that had almost no Se in them. Many had only a
half milligram per dose.
Over the past few years, all the blood tests have
shown my gelding to be at the low end of the normal range for Se.
Recently, I upped his vitamin E dosage considerably using gelcaps (thanks,
Susan), and now I'm awaiting test results to see if his body's uptake of the Se
has improved.
I originally starting adding wet, shredded
beetpulp to his feed in order to keep him from sifting supplements out of
his grain. Seems like an eon ago.
