Effect of oat supplementation on the liveweight gain and carcase characteristics of yearling Friesian steers grazed on green pasture in western Victoria

Abstract

Friesian steers aged nine months were set stocked on pasture from May 28 to November 29 at 2.5 and 5.0 steers ha-1 and were supplemented with oats at four levels-nil, 1.8, 3.6 kg steer-1 day-1 and ad libitum. Growth responses to oat supplementation were obtained at both stocking rates in winter but only at 5.0 steers ha-1 in spring. Average daily gains (kg day-1) during the entire six months of the experiment were, at the four oat feeding levels, respectively: 0.67, 0.72, 0.94 and 0.92 at 2.5 steers ha-1 and 0.1 8, 0.35, 0.56 and 0.79 at 5.0 steers ha-1. A mean conversion rate of 10.1 kg of additional liveweight gain per 100 kg of oats consumed was obtained when the spring values for steers stocked at 2.5 ha-l were omitted. Substitution in the intake of grain and pasture was apparent, as indicated by differences in herbage availability, in all treatments except in steers stocked at 5.0 ha-1and supplemented with oats at 1.8 and 3.6 kg day-1. Because of their 'lanky' conformation, the carcases were downgraded by the meatworks even though they all had high muscle contents and some had up to 7 mm of backfat at the 10th rib.