Supplementation to improve the production of yearling steers grazing poor quality forage. 1. The effects of forage type and a cottonseed meal supplement

Abstract

Yearling Hereford steers grazed on either oat stubble or dry annual pasture and were supplemented with daily rations of 0, 200, 400, 600, 800 or 1000 g/steer of pelleted cottonseed meal. Steer growth rates increased with increasing level of supplement from 500 to 961 g/steer.day on the oat stubble and from 128 to 613 g/steer.day on the dry pasture. The growth responses appeared to be not only due to the metabolizable energy ofthe supplement, but also due to greater forage consumption. Compensatory growth during the 3 months after cessation of supplementation reduced the advantage of the supplementary feeding only slightly. The cottonseed meal supplement was chosen after a preliminary experiment which compared the influence of four protein supplements on the ad libitum intake of a low-quality roughage by weaner lambs. The supplements (pelleted cottonseed meal, pelleted lupins, soybean meal, and rolled lupins) improved consumption of roughage by 67, 49, 46 and 35%, respectively. An in vitro determination of ammonia and amino acid production from these supplements showed that pelleted cottonseed meal and soybean meal are most resistant to degradation.