Effect of avoparcin on growth rate in grazing beef cattle weaners in the dry season in northern Australia.

Abstract

Proc. Aust. Soc. Anim. Prod. Vol. 17 EFFECT OF AVOPARCIN ON GROWTH RATE IN GRAZING BEEF CATTLE WEANERS IN THE DRY SEASON IN NORTHERN AUSTRALIA W R DODEMAIDE*, J A LINDSAY**, B GULBRANSEN# and P J ROUND## Avoparcin (Avotana 100, American Cyanamid growth promotant under lot feeding conditions ascertain whether improved growth rates would Australia, pen trials and paddock trials were 389 Company) is used as an in-feed in beef cattle in Europe. To occur under grazing conditions in conducted. Avoparcin was administered following mechanical mixing at the appropriate rate into supplements which were offered ad libitum to beef cattle weaners fed pasture hay in pens or grazed on pasture in paddocks. The supplements used as a vehicle to supply Avoparcin included molasses (Mol) alone or with 3% or 8% urea (M3U or M8U), cottonseed meal (CSM) and protected protein in the form of formaldehyde-treated cottonseed meal plus 12% urea (UPP). The allowance of Avoparcin is expressed as mg per head per day (mg/hd/d), the growth rate is expressed as average daily gain (ADG), and the average daily feed consumption is expressed as average feed intake (AFI). Table 1. Average daily gains and average feed intakes in steers given Avoparcin in various supplements. Although not all differences in growth rate were statistically significant, when compared with control group, there was a positive response to Avoparcin in all studies undertaken, with improvements in average daily gain of at least 9%. Feed intakes did not vary consistently or significantly between the Avoparcin groups and their respective controls. These results demonstrate that grazing beef cattle weaners growing at various rates will respond favourably to Avoparcin taken at between 75 and 390 mg per head per day. * Cyanamid Australia Pty Limited, P.O. Box 9, Baulkham Hills; N.S.W. 2153 ** Department of Primary Industries, Millaroo, Qld. 480'7 # Department of Primary Industries, Gayndah, Qld. 4625 #nu Department of Primary Industries, P.O. Box 931, Townsville, Qld. 4810 b Registered trademark of American Cyanamid Company