Effect of strategic supplementation with different proportion of agro-industrial by-products and grass hay on body weight change and carcass characteristics of tropical Ogaden bulls (Bos indicus) grazing native pasture

Abstract

The effect of supplementation with agro-industrial by-products and hay on body weight change and carcass characteristics of Ogaden bulls grazing natural pasture was investigated at Haramaya University beef farm. Eighteen uniform and healthy Ogaden bulls with initial mean body weight of 258.5±41.5 kg were selected from the University farm and randomly assigned to one of the three treatments. Treatment 1 (T1; Control) constituted grazing natural pasture alone, while treatments 2 and 3 constituted grazing natural pasture supplemented with agro industrial by-products and hay at a ratio of 25:75 and 50:50, respectively. Average daily body weight gain was highest (P < 0.05) for bulls in T3 (0.65±0.05 kg), while no difference was observed between bulls in T2 (0.47±0.05) and T1 (0.39±0.05). Mean body condition score was highest (P < 0.05) for bulls in T3 and T2 compared to bulls in T1. Feeding period influenced (P < 0.05) body weight change and body condition score , where bulls in the final period were heavier and had better body condition score than the preceding periods Feeding Ogaden bulls with T3 and T2 improved (P < 0.05) empty body and hot carcass weights compared to grazing alone (T1). Dressing percentage was slightly higher for bulls in T3 and T2 compared to bulls in T1. Thus, it could be concluded that supplementation with T3 would be a better feeding strategy to improve the performance of Ogaden bulls under tropical environment. Key words: Body weight, body condition score, carcass and non-carcass components, supplementation, Ogaden bulls.