Response of cobalt deficient lambs to cobaltic oxide pellets

Abstract

Extract

In New Zealand, cobalt-containing drenches are recommended for the field diagnosis of cobalt deficiency, but find little use as a routine method of controlling the disease. For the latter purpose, cobaltized licks have a place on extensively-grazed untopdressed hill country. Otherwise, topdressing pastures annually with cobalt sulphate, usually as cobaltized superphosphate, has proved the best method of prevention (N.Z. Dept. Agric, 1954; Andrews, 1956). In Australia, however, greater reliance has been placed on drenches and licks, partly because cobalt topdressing is regarded as uneconomic on the extensive undeveloped holdings usually associated with cobalt deficiency in that country, and partly because the effects of cobalt applied to the land have often proved ephemeral, particularly on the acutely-deficient calcareous coastal sands (Lee, 1950; Bennetts, 1955). However, recent work in South Australia opens up an entirely new approach to the control of cobalt deficiency disease. Dewey et al. (1958) report that when semi-porous pellets containing cobaltic oxide are administered to sheep they are retained in the reticulum, or less commonly in the rumen, and release a continuous and adequate supply of cobalt to the animal. Phalaris staggers and cobalt deficiency disease can be prevented in this way.