Abstract:
Proc. Aust. Soc. Anim. Prod. Vol. 17 FORTIFIED MOLASSES FORMULATIONS FOR SHEEP D.H. COBON*, D.G. McRENNA*, G.M. MURPHY** and R.K. SHEPHERD *** Fortified molasses supplements are gaining acceptance within the grazing industry and their worth to sheep has been documented (Bird et al. 1987). Molasses, urea and salt supplements have the potential for providing low cost energy and protein in times of drought. In this study we examine the response to molasses containing varying concentrations of urea and one level of salt. One hundred and seventy-five Peppin Merino wethers were stratified on the basis of live weight and randomly allocated to one of four treatments. They were depastured on to small paddocks (two hectares) that closely represented pastures under severe drought conditions. Treatments were M3U (3% urea in molasses), M5U (5% urea in molasses), M8U (8% urea in molasses) and M3U4S (M3U plus 4% salt). Measurements of supplement intake, liveweight (LW) change, survival, rumen ammonia and pH and plasma concentrations of Na, K, Ca, Mg were recorded. Table 1 Effect of different urea and salt levels in molasses on the performance of grazing wethers Means within rows with different superscripts differ significantly P < 0.05; S.D. - standard deviation; na - not analysed; ( ) - number sampled In this study the level of salt ingested was not sufficient to limit supplement intake; however, the performance of group M3U4S was significantly better. Large variation in rumen ammonia levels between sheep (range 1.7 to 34.7 Concentration of K in mg/lOO mL) indicates a wide range of supplement intake. plasma of sheep in group M3U4S was significantly different from that in the M3U group (5.0 vs 5.4 mmol/L), but is unlikely to be of biological importance. Concentrations of the other minerals were not different. Visually the sheep in group M3U4S were stronger and more active than sheep in the other groups; this may be due to the correction of an induced sodium deficiency from the high potassium levels in molasses. The use of a non-toxic intake regulator has practical and economic advantages if a suitable proportion can be found. BIRD, A.R., COBON, R.I., MURPHY, G.M., and STEPHENSON, R.G.A. Anim. Nut. Aust. p. 8A. (1987). Rec. Adv. * ** *** Dept Primary Industries, Toorak Research Station, Julia Creek, Q. 4823. Dept Primary Industries, Yeerongpilly, Q. 4105. Dept Primary Industries, Oonoonba Veterinary Laboratory, Townsville, Q. 4810.