Improving growth rates of Ongole crossbred bulls by formulation and level of supplement of by-products

Context Formulating diets using agro-industrial by-product concentrates to increase the growth performance and cost efficiency of Ongole crossbred bulls.Aims This study was conducted to evaluate the inclusion of agro-industrial by-products of dried cassava powder (DCP), mixed copra meal (CM), palm kernel cake (PKC) and soybean hull (SBH) into rations at low and high levels of feeding on bull liveweight gain and farmer profitability.Methods Fifty Ongole crossbred bulls with an initial bodyweight (BW) of 227±66.5kg and aged between 12 and 18months, were arranged in a randomised complete-block design of five treatments, with 10 heads per treatment. The control group (T0) was provided the current feeding system (CFS) fed ad libitum. The supplemented treatments consisted of CFS ad libitum+concentrate (50% DCP, 25% CM, 25% PKC) at 1% BW/day (T1), CFS ad libitum+concentrate (50% DCP, 25% CM, 25% SBH) at 1% BW/day (T2), CFS ad libitum+concentrate (50% DCP, 25% CM, 25% PKC) at 2% BW/day (T3), CFS ad libitum+concentrate (50% DCP, 25% CM, 25% SBH) at 2% BW/day (T4). The experiment was conducted for 12weeks.Key results The BW gain over 12weeks (kg) for T0, T1, T2, T3 and T4 was 39.5, 56.2, 68.9, 57.5 and 62.1kg respectively. The income over feed cost was significantly higher in T2.Conclusions Supplementation with by-products increased bull liveweight gain compared with current feeding practices. A concentrate supplementation of DCP mixed with CM and SBH at 1% BW/day was the most effective and profitable supplementation method to increase income of farmers in this district and there was no advantage of increasing the level of supplement.Implications A combination of DCP, CM and SBH to form a concentrate supplement and fed at 1% BW/day will increase bull liveweight gain and income of farmers.