PRODUCTIVE AND ECONOMIC EVALUATION OF THE INCLUSION OF WHOLE GRAIN OAT (Avena sativa L.) AND LUPIN (Lupinus angustifolius L.) IN WINTER FATTENING RATIONS FOR HEIFERS

Abstract

In cattle finishing rations, cereal and legume grains are included ground with forages in order to increase grain starch and protein availability, which facilitates use by ruminal microorganisms. The use of whole grains may decrease feed efficiency and live weight gain. The objectives of the
experiment were to evaluate the productive and economic performance of winter finishing penned system for heifers fed with barley silage (Hordeun vulgare) supplemented with whole grain oat and australian lupine. In an completely randomized block design, 28 Hereford × A. Angus heifers of 22
months of age and 353 kg initial live weight were submitted to treatments: T1 barley whole crop silage and whole grain oat and lupine; T2 silage and ground oat and whole grain lupine; T3 silage and whole grain oat and ground lupine ; and T4 silage and ground oat and lupine. Treatments were isoproteic and isocaloric, and were supplied once daily in the morning during 74 days. Daily live weight gains were 1.423; 1.485; 1.216; and 1.336 kg animal-1, values that were statistically similar (p ? 0.05); daily dry matter intake corresponded to 9.10; 9.20; 9.01; and 9.00 kg DM animal-1 ; feed efficiency were 6.39; 6.20; 7.41; and 6.74 kg DM of feed consumed by kg-1 live weight gain, for treatments 1 to 4, respectively. Dressing percentage, rib eye area and carcass pH showed no significant differences (p ? 0.05). It was concluded that finishing heifers with rations including barley silage supplemented with either whole or ground grains of oat and lupine does not affect the animal response, being T1 the lowest cost ration, which indicates that grain grinding is not necessary.