Abstract:
This study examined the effects of clenbuterol on the growth of young cattle (160 kg) that were fed a restricted quantity of a low-quality hay to simulate dry-season pasture conditions in the tropics. Twenty Brahman steers were used. Ten control animals lost an average of 0.24 kg/day in the first 17 days, then maintained their liveweight for the remaining 21 days of the experiment. By contrast, 10 clenbuterol-treated animals lost 0.3 kg/day for the first 17 days of the experiment, then continued to lose weight at a steady rate of 0.15 kg/day. In control steers, plasma concentrations of urea-nitrogen decreased over the course of the experiment, and this effect was accelerated by clenbuterol treatment (