Abstract

The impact of high quality supplementary feeds on cattle growth rates was investigated in 2 experiments. The first experiment was conducted during late summer (8 weeks) and involved 5 treatments which were replicated twice: no supplement, 2 and 4 kg rolled maize grain/hd/d; and 2.3 and 4.6 kg DM/hd/d high quality pasture silage. The second experiment was conducted during late winter (8 weeks) and involved 3 treatments which were replicated twice: 0, 2 and 4 kg/hd/d rolled maize grain. Rising 2 year steers were used and all pre- and post-grazing pasture masses were similar between treatments within each experiment. During the summer experiment pasture quality was poor and steer liveweight gains for the 5 treatments were: -0.04, 0.44, 0.55, 0.29 and 0.36 kg/hd/d respectively. In contrast, pasture quality was high during the winter experiment and liveweight gains were: 0.93, 1.09 and 1.25 kg/hd/d respectively. The combined results of this experimental series show a consistent liveweight gain response to supplementation of high quality feeds, under both low and high quality pasture conditions. A general response of 0.15-0.20 kg liveweight gain/kg DM grain can be expected. Given current grain prices in New Zealand, its use as a tactical supplement in beef finishing systems will be confined to overcoming variable forage supply and attaining supply contract premiums. Pasture silage is an alternative supplement for summer, but high quality is a pre-requisite.

CJ, Boom, and GW Sheath

Proceedings of the New Zealand Society of Animal Production, Volume 59, , 162-167, 1999