Aspects of the faecal excretion of selenium by sheep

Abstract

When 12 μg ⁷⁵Se-selenious acid was introduced into the rumens of sheep 51% was recovered in the dung over a 72-hour period. This confirms that the major route of excretion of selenium in ruminants is not via the urine as in monogastric animals. Chemical fractionation of the dung showed that most of the selenium was present in forms insoluble in water or solvents. The insoluble fraction appeared to be approximately half inorganic and half protein-bound. In a pot experiment negligible amounts of selenium were taken up from dung into herbage of perennial ryegrass over a period of 53 days.