Abstract

This study tried to make use the ample supply of rice straw as the source of roughage. An experiment was conducted to evaluate effect of phosphorus and sulphur supplementation in rations containing ammoniated rice straw in beef cattle diets. The experiment used in randomized block design with cattle of 90±5.63 kg live weight. The experiment diets composed of 50% rice straw and 50% concentrate. The treatment were A = 50%rice straw, previously treated with 4% urea B = A+5% cassava leaves, C = B+0.4% P, D = C + 0.45%S. Differences among treatment means were examined using Duncan multiple range test. The results showed that there were significant differences of the consumption of dry matter and organic matter, digestibility of dry and organic matter and daily gain between treatments. The results indicated that intake, digestibility and daily gain of diets contains ammoniated rice straw with P and S supplementation were significantly higher than the control diet (p<0.05). It is concluded that P and S supplementation is important to improve degradability and daily gain of rations contain rice straw ammoniated. The best result showed at treatment D where, dry matter intake was 3407 g day-1, organic matter intake was 3340 g day-1, digestibility of dry matter was 64% and digestibility of organic matter was 66.90% and daily weight gain was 610.25 g day-1.