DRY-MATTER, CALCIUM AND PHOSPHORUS IN OVI NE RATIONS CONTAINING COTTONSEED MEAL, YEAST AND UREA

This experiment was carried out with 24 male lambs of Polwarth (Ideal) breed with 21 kg of mean live weight. Digestibility of isoproteic rat ions including three different protein sources (cottonseed meal, RA; d ry yeast, RL; and urea, RU) was studied. Data were analized in a compl etely randomized design with three treatments and eight replications. Digestibility coefficients of dry matter were smaller (P<0.05) in rati on RA (58.29%) than in rations RU and RL (64.07 and 62.19%). The mean amounts of apparent absorption of mineral matter did not change signif icatively (P>0.05) among rations. The mean quantities of calcium and p hosphorus absorbed did not differ (P>0.05) among treatments, with valu es of 26.53; 30.04 and 34.97% for calcium and 24.67; 43.10 and 32.40% for phosphorus in rations RA; RL and RU, respectively. Based on these results, and considering the data examined, it was concluded that the use of these three sources of protein can be employed for growing lamb s.