Experimental Production of Magnesium Deficiency in Lambs on a Diet containing Roughage

Abstract

HYPOMAGNESÆMIC tetany occurs (a) in young ruminants raised exclusively on milk diets and (b) in adult ruminants near the time of parturition, when grazing in certain areas, in the spring and autumn. The latter conditions are difficult to produce experimentally and the causative factor(s) are not well understood. The former type is readily reproduced^1–5 but has been done only under conditions which inhibit normal rumen development, that is, the abnormally prolonged feeding of a roughage-free diet. In this communication, we wish to report the experimental production of hypomagnesæmia in lambs, on a roughage-containing diet of composition as given in Table 1 (diet 1). This diet contains only 0.02 per cent (magnesium air-dry basis, but is adequate in other respects. Reagent grade chemicals were used in preparation of the mineral mix and dicalcium phosphate as the calcium source.