Increased live weight gain and wool weight from anthelmintic drenching of ewe hoggets in South Canterbury

Abstract

Abstract Over a period of five years the production responses obtained from drenching young sheep with thiabendazole were examined in 14 trials covering eight localities in South Canterbury. In the first four trials three drenches given at monthly intervals between January and June produced responses ranging from 1.6 lb to 12.6 lb live weight gain and 0.2 lb to 1.6 lb increase in greasy fleece weight. Over the remaining 10 trials drenching at monthly intervals from December or January until August or September increased mean live weight gain by 13.3 lb (range 6.3 lb to 18.6 lb) and mean greasy fleece weight by 1.3 lb (range 0.9 lb to 2.4 lb) compared with undrenched controls. The results also indicated that four drenches, given in January, March, May, and July, could achieve responses averaging 74% of the live weight gain and 79% of the increased greasy wool production from sheep drenched at monthly intervals.