Response to supplementary sorghum grain by cattle grazing oats

Abstract

Seven groups each of five 18-month-old steers grazed oats (Avena sativa) at allowances ranging from 0.40 to 0.08 ha head-l. A further group in a concrete yard was fed ad libitum a diet consisting solely of sorghum grain. Six of the grazing groups were supplemented with ad libitum sorghum grain. The steers were slaughtered after an average of 100 days on trial. The mean daily grain dry matter consumption of grazing steers ranged from 2.90 to 6.52 kg head-1. Carcase gain ha-1 was linearly related to grain consumption ha-l and increased by 0.097 kg for each kg of grain dry matter consumed. Fasted liveweight gain and growth rate were shown to be unsatisfactory measures of animal performance in pasture/grain feeding systems.