Barley, oat or lupin supplements for cattle fed hay

Abstract

Proc. Aust. Soc. Anim. Prod. 1994 Vol. 20 BARLEY, OAT OR LUPIN SUPPLEMENTS FOR CATTLE FED HAY J.B. ROWE, J.L. JACOBS, F.J. COUPAR and J.M. SNOWDON Cattle Industries Branch, Dept of Agriculture Baron-Hay Court, South Perth, W.A. 615 1 Hay is the most common supplement fed to cattle when paddock feed is limited. The use of cereal Orain is normally confined to feedlot operations. The cost of feeding hay ($/unit of digestible energy) is a almost always greater than the cost of cereal grain. The choice of this more expensive supplement is due to the safety with which hay can be fed compared with the risk of acidosis associated with feeding cereal grain and the inconvenience of feedin g grain in small amounts daily or twice weekly. The use of virginiamycin to reduce the risk of acidosis facilitates feeding of grain at weekly intervals and opens up new possibilities for simple and cost effective use of cereal grains as supplements for grazing ruminants (Rowe and Zorrilla Rios 1993). The aim of this experiment was to investigate the effect of varyin g amounts of barley, oat or lupin grain on feed intake and liveweight gain in cattle with free access to hay. Cattle weighing approximately 300 kg were housed individually and fed hay ad Zibitum. Barley grain and oat grain were mixed with limestone (1%) urea (1%) and virginiamycin (20 g/t). Urea solution was added to all hay to provide 10 g urea/kg dry matter. All grain supplements were hammermilled and were fed in a separate bin to the hay at weekly intervals at levels designed to supply an equivalent of 12, 24 or 48 MJ ME/day. Intake of hay and grain was measured each day and animals were weighed fortnightly. Supplements were fed for a period of 70 days. There were 5 cattle in each treatment group and 15 animals were fed hay only. There was no significant effect of the type of grain on liveweight gain or hay intake. There was a linear increase in liveweight gain (Y, kg/day) in response to all grain supplements (X, kg/day) described by the equation: Y = 0.62 + 0.16X (R' = 0.63) and a linear decrease in hay intake (Y? kg/day) in response to increasing amounts of all grains (X, kg/day) described by the equation: Y = 7.35 - 0.80X (R' = 0.71). Table 1. Intake of grain (kg/day) and hay (kg/day) and the rate of liveweight gain (kg/day) in cattle fed varying amounts of barley, oats or lupin grain as a supplement to hay It is concluded that cereal grains may provide a convenient and cost-effective alternative to lupins as supplements for cattle on roughage-based diets provided sufficient nitrogen is available for microbial activity and virginiamycin is used to control adverse effects associated with the rapid fermentation of starch. This study was partly funded by the MRC and SmithKline Beecham Animal Health. ROWE, J.B. and ZORRILLA-RIOS, J. (1993). In 'Recent Advances in Animal Nutrition in Australia 1993', (Ed D.J. Farrell) pp. 89-96 (University of New England: Armidale). 334