THE EFFECT ON THE GROWTH OF BEEF HEIFERS OF AVOPARCIN IN A FREE-CHOICE MINERAL MIXTURE

Abstract

Twenty crossbred beef heifers (7–9 mo) were fed grass silage ad libitum for 90 days, with a free-choice mineral mixture containing avoparcin (8 g/kg) while 20 other heifers were fed similarly but without avoparcin. Heifers offered the supplement gained 27% faster (P < 0.01) than controls, with no apparent effect on silage intake. Key words: Avoparcin, administration, cattle, growth