Abstract 333

Smith,GH; Warren,-B

Rutherglen Research Inst., Dep. Agriculture and Rural Affairs, Chiltern Valley Road, Rutherglen, Vic. 3685, Australia.

Australian-Journal-of-Experimental-Agriculture-and-Animal-Hu bandry. 1986, 26: 1, 1-6; 22 ref.

Yearling Hereford steers grazed on oat stubble or dry annual pasture and were supplemented with pelleted cottonseed oilmeal 0, 200, 400, 600, 800 or 1000 g daily. Growth rates increased with increasing level of supplement from 500 to 961 g daily on the oat stubble and from 128 to 613 g daily on the dry pasture. The growth responses seemed to be not only due to the metabolizable energy of the supplement, but also due to greater forage intake. Compensatory growth during the 3 months after cessation of supplementation reduced the advantage of the supplementary feeding only slightly. The cottonseed oilmeal supplement was chosen after a preliminary experiment which compared the influence of 4 protein supplements on the free intake of a low-quality roughage by weaner lambs. The supplements (pelleted cottonseed oilmeal, pelleted lupins, soyabean oilmeal and rolled lupins) improved intake of roughage by 67, 49, 46 and 35%, respectively. Estimation of ammonia and amino acid production in vitro from these supplements showed that pelleted cottonseed oilmeal and soyabean oilmeal are most resistant to degradation.