Beef production from lucerne and subterranean clover pastures. 1. The effects of pasture, stocking rate and supplementary feeding

Abstract

The production and management of weaner steers on two pasture types were studied over 3 years at Wagga Wagga in southern New South Wales. One pasture (LC) was sown with a mixture of lucerne (Medicago sativa) and subterranean clover (Trifolium subterraneum) and the other (C) was sown only with subterranean clover. On each pasture the management treatments were 1.3 and 2.0 steers ha-' in 1975, and 2.1 and 3.0 steers ha-1 in 1976 and 1977, with a grain supplement at the heavier stocking rate in all years. Each year, steers gained more liveweight in February-March or April-May on LC than on C, and this advantage was maintained or increased until slaughter in the following January. The faster growth of steers on lucerne-clover was always associated with an increased supply of green herbage. Annual liveweight gain on LC exceeded that on C by 20-30 kg/head in 1975 and 1977, and by up to 90 kg/head in 1976, when the rainfall pattern was unsuitable for clover growth. Carcases from steers on LC were heavier (all years), covered with a greater depth of fat (1 975 and 1976) and showed better eye muscle development (1 76 and 1977) than those on C. In 1975, neither stocking rate nor supplementary feeding affected liveweight or carcase development. In the following 2 years, increasing the stocking rate from 2 to 3 steers ha-1 reduced annual liveweight gains by 35-40 kg/head. Oat grain supplements (2-3 kg/head day-1 in February-March, June-July and December-January) improved weight gains and carcase quality on both pasture types in 1977, but only on C in 1976