The effect of cobalt supplementation, as an oral drench or pasture treatment, on the growth of lambs

Abstract

SUMMARYIn a trial to investigate an ill-thrift problem in lambs on an Exmoor farm frequent oral drenching with cobalt sulphate was compared with pasture spraying. There were two groups of twin lambs reared respectively on sprayed and unsprayed pasture. One partner from each twin set was drenched with cobalt sulphate every two weeks. There were no significant differences in live-weight gain up to weaning time. Thereafter there was little difference in the progress of the twins on sprayed pasture. On the unsprayed pasture, however, the drenched lambs had gained an average of 9 lb live weight more than their partners over a period of 15 weeks but were still about 7 lb lighter than the lambs on sprayed pasture.Blood vitamin B12 concentration, assayed with Lactobacillus leichmannii, was not well correlated with the treatment of the groups and all values were above commonly accepted critical levels.