The effect of single doses of selenium salts on whole blood levels of selenium in ewes on a selenium-deficient diet

Abstract

Equivalent doses of sodium selenate and sodium selenite were equally effective in preventing selenium deficiency in ewes on a diet containing a very low level of selenium.

There was a wide variation between animals in blood-level response to a single dose of selenium, and in the time for which it would satisfy ewe requirement. When ewes were fed a hay ration containing a very low level of selenium, a single dose equivalent to 5 mg selenium would give protection for at least 6 months when injected subcutaneously compared with 4 months when administered orally.

There was no significant difference in the response to subcutaneous injection of sodium selenate solution with needles of different sizes. There was no difference in effect between administration of 1 ml into the sheep's mouth or of 10 ml of a 1 in 10 dilution directly down the animal's throat.