Ravi Kumar .M (MAJOR)Raja Kishore .KVenkata Seshaiah .ChBaswa Reddy .PMOUNICA KOLLI2024-07-072024-07-072024-01https://krishikosh.egranth.ac.in/handle/1/5810211552In a completely randomized design (CRD), 24 Murrah buffalo bull calves were randomly allotted to three dietary treatments (T1 to T3) comprising of green fodder viz., Hybrid Napier, concentrate mixture and paddy straw viz. normal paddy straw-NPS (T1; control), delignified paddy straw (DPS)-50% (T2) and delignified paddy straw -100% (T3), respectively. A concentrate mixture of 20% CP was prepared by using feed ingredients like maize, DORB, soybean meal. Weighed quantities of paddy straw and concentrate mixture were mixed every day and offered to calves in TMR form. All the three diets were evaluated for their effect on growth, nutrient utilisation, carcass characteristics and cost economics in growing buffalo bull calves. The percent DM, OM, CP, EE, CF, NFE, TA, NDF, ADF, hemi cellulose, cellulose and ADL were 94, 86.54, 5.57, 2.77, 33.55, 44.65, 13.46, 72.2, 49.34, 22.80, 38.1 and 5.43; 92.73, 91.41, 3.38, 2.97, 55.08, 29.98, 8.59, 81.32, 56.04, 25.28, 29.36 and 4.12 per cent in normal paddy straw and DPS, respectively. The calcium and phosphorous content in normal paddy straw and DPS were 0.42 and 0.105; 0.46 and 0.07 per cent, respectively. Feeding delignified paddy straw to growing buffalo bull calves had no effect (P>0.05) on DM, CP, EE and ADF digestibility as compared to control. However, digestibility of OM, CF, NFE, NDF, cellulose and hemicellulose were significantly higher (P<0.01) in T3 group as compared to the control group. The dry matter intake (kg/day) was significantly higher (P<0.01) in T2 group followed by T3 and T1. Inclusion of delignified paddy straw in the diet had no effect (P>0.05) on DMI expressed as % BW and g/kg W 0.75 among the different dietary treatments. Higher (P<0.05) water intake (L/day) in T2 and water intake (L/kg DMI) in T3 was observed in the calved fed delignified straw as compared to control. Further, better dung score (2.50) was recorded in T2 compared T1 (3.45) and T3 (1.50). The present study indicated that feeding of delignified paddy straw in buffalo bull calves had no effect on the body weight gain (kg), ADG (g/d) , feed efficiency and cost of feed/kg gain among the different dietary groups. However, there is a numerical increase in body weight gain (kg), ADG (g/d), better feed efficiency and decreased cost of feed/kg gain in T2 group compared to the T1 and T3 group. The cost of feed /kg gain decreased by ₹ 24.00 and 12.81 in T2 and T3, respectively, as compared to T1. Feeding of delignified paddy straw had no effect (P>0.05) on DCP content expressed as % in diet consumed and intake (kg). However, the TDN content expressed as % in diet consumed was higher in T3 group compared to T1 and T2. The carcass studies in buffalo bull calves fed delignified paddy straw at different levels had no effect (P>0.05) on the slaughter weights, wholesale cuts expressed as percent of carcass weight, yield of visceral organs expressed as percent of pre-slaughter weight. Thus, it was concluded that replacement of normal paddy straw with delignified paddy straw at a rate of 50% found to be superior with increased body weight gain, nutrient utilisation and decreased cost of feeding compared to 100% replacement in buffalo bull calves.EnglishThesis