Abstract:
Proc. Aust. Soc. Anim. Prod. (1978) 12: 215 LEVELS OF AUTUMN HAY FEEDING AND WINTER PERFORMANCE OF STEERS S.J. WALSH* and S.K. ANDERSON* In Victoria, a grazing system enabling yearling steers to be marketed in spring before peak markets, can increase returns for the producer. The main barrier to spring turn-off is low steer weight gain during winter when pasture growth is low. This experiment measured the effect of hay quantity (ad lib. and maintenance) and quality (2 hays) fed as a sole ration in autumn, on the weight and fatness of yearling Hereford steers grazing autumn saved pasture in winter. Three groups of 8 steers were each restricted in autumn to 0.2 ha of their grazing area ( a feedlot) and for 80 days were fed either :- Tl) ad lib. sub. clover hay 17.6% C-P., 73% D-DM), T2) ad lib. grass/clover hay (11.4% C-P., The three groups 56% D.DM),T3) grass/clover hay at maintenance. then grazed together for 54 days on 8.61 ha of perennial ryegrass and * sub. clover. Pasture available at turn out (20/7)was 1900 kg/ha dry matter and did not fall below 1600 kg/ha. For treatment 4 (T4) . ' 8 steers were set stocked on 2.87 ha with no hay supplements. Mean pasture available during winter was 1060 kg/ha. Bailey and Bishop (1973) found that steers fed hay in feedlots then grazed, lost weight compared to steers continuously grazed. However, we-found that steers initially fed ad lib. hay (Tl and T2), then grazed on autumn saved pasture, were significantly heavier in final live weight (39 kg and 21 kg P<O.Ol) in carcass weight 23 kg and 13 kg PCO.01) and had greater fat depth (3.9 and 2.4 mm Steers initially P.<O.Ol) than steers continuously grazed (T4). fed hay at maintenance (T3) had a similar live weight and carcass' weight to T4, but had significantly greater fat depth (1.5'mm PCO.01) Quality of hay fed (Tl and T2) had a significant effect on final live weight, carcass weight and fat depth (P<O.Ol). BAILEY P-J. and BISHOP A.H. (1973),Aust. J. exp. Agric. Anim. Husb. 13 =Z :621. a - * Department of Agriculture, Warragul, Victoria. 215. -