Utilization of Urea and Urease Treated Rice Straw by Indigenous Growing Cattle

The experiment was conducted to study the effect of treatment of rice straw with urea and a urease contain-ing midden soil on the chemical composition of treated rice straw, feed intake of the animals, nutrients di-gestibility, body weight gain, feed conversion efficiency and overall economy of feeding for a period of 105 days. Twelve indigenous growing cattle (live weight 130.00±1.67 kg) were selected and divided into four groups having three animals in each group. The animals received 3.0% urea + 2.0% midden soil treated rice straw (group A), 3.0% urea + 3.0% midden soil treated rice straw (group B), 3.0% urea + 4.0% midden soil treated rice straw (group C) and 3.0% urea + 5.0% midden soil treated rice straw (group D). In addition, all the animals were supplied with 2 kg green grass, 450 g concentrate mixture and 40 g salt per 100 kg body weight. Treatment of rice straw with 3.0% urea+ 2.0% midden soil lead to an increase in crude protein con-tent from 3.30 to 7.08%, which was further increased by 7.40, 7.90 and 8.14% if treated with 3.0% urea + 3.0% midden soil, 3.0% urea + 4.0% midden soil and 3.0% urea + 5.0% midden soil, respectively. The total live weight gain by the end of the experimental period (105 days) was 39.00, 42.50, 46.50 and 49.00 kg for groups A, B, C and D respectively. The addition of 5.0% midden soil as a urease source with 3.0% urea (D) treated rice straw not only significantly (P < 0.01) increased the coefficient of digestibility of dry matter (DM), crude protein (CP), crude fibre (CF), ether extracts (EE) and nitrogen free extract (NFE), but also significantly (P < 0.05) increased the coefficient of digestibility of (OM) compared to treatment of rice straw with 3.0% urea + 4.0% midden soil (C), 3.0% urea + 3.0% midden soil (B) or 3.0% urea + 2.0% midden soil (A). Digestible organic matter (DOM), digestible crude protein (DCP), digestible crude fibre (DCF), digestible nitrogen free extract (DNFE) and total digestible nutrients (TDN) contents were significantly (P < 0.01) higher in diet D, compared to diets A, B and C. Total profit of meat production in group D was significantly higher (P < 0.01) than in groups A, B and C.