The aetiology of Phalaris staggers in sheep. II. The toxicity to sheep of three types of pasture containing Phalaris tuberosa

Abstract

The seasonal occurrence of phalaris staggers In sheep on three types of pasture containing Phalaris tuberosa L., during periods of 3 years, 2 years, and 1 year respectively, is described. A relatively pure stand of phalaris proved toxic to sheep for almost 6 consecutive months of its growing period. The consumption of appreciable quantities of lucerne, subterranean clover, or other plants, along with the phalaris, reduced the hazard very considerably. Neither the dormant tubers nor the standing straw of phalaris proved to be toxic. The widespread occurrence of phalaris staggers on a diversity of sol1 types is reported and the possibilities that the toxicity of phalaris may fluctuate according to climate and terrain are discussed. The view is advanced that actively growing phalaris is potentially toxic to sheep under most, if not all, circumstances.