Nutrient utilization by Murrah buffaloes (Bubalus bubalis) as influenced by varying levels of urea molasses mineral block on wheat straw based diets

To ascertain the optimum intake of urea molasses mineral block (UMMB) as a supplement on wheat straw based diets, twelve adult male Murrah buffaloes (Bubalus bubalis) (390±9.0 kg; 4 y) were assigned to three equal groups in a completely randomized design. To minimize individual diurnal variation, the animals on Diets 1, 2 and 3 were fed fixed quantity of UMMB at the level of 400, 600 and 800 g, dissolved in 1000 ml of water and mixed manually with 5600 g chaffed wheat straw uniformly, for a preliminary period of 21 days followed by a metabolism trial of seven days duration. An increased (P<0.05) intake of crude protein and decreased intake of ether extract, acid detergent fibre (ADF), cellulose (g day−1), dry matter and total digestible nutrients (TDN) per unit metabolic body size (kg W0.75) were observed on 800 g UMMB as compared to similar intake on other diets. The animals from all the three treatments digested most of the nutrients to a similar extent, except dry matter and organic matter, the digestibility of which was depressed on feeding 800 g UMMB daily. Inspite of significantly (P<0.05) lower digestible intake of ADF and cellulose in animals offered 800 g UMMB, their digestibility were comparable among the diets. All the animals were, though, in positive nitrogen, calcium and phosphorus balance, animals fed 800 g UMMB daily lost body weight probably due to the insufficient energy supply. Since supplementation of UMMB at 400 and 600 g levels exhibited similar results and itʹs inclusion beyond that had no beneficial effect, it can be concluded that a level of 400 g UMMB seems to be optimum to maximize utilization of nutrients from wheat straw based diets to meet maintenance requirements of adult male buffaloes.