Abstract:
The experiment was conducted at Haramaya University Beef fattening station, to evaluate the effect of maize silage inclusion at different levels on feed intake, growth performance, carcass characteristics, and meat quality. Twelve castrated Harar oxen of average age 6 years with the initial body weight of 229±1.18 kg (mean+SE) were used for the experiment. The animals were randomly distributed to four treatments each with three replications in a completely randomized design. The dietary treatments contained the maize silage inclusion at a proportion of 0, 33, 67, and 100% for T1, T2, T3, and T4, respectively. The rest proportion of roughage was fulfilled by native grass hay and offered ad libitum to respective treatment groups. The experimental animals were watered and supplemented with concentrate ration at 1.25% of their body weight twice a day. The feeding trial lasted for 90 days. All animals were slaughtered at the end of the trial for the evaluation of carcass and meat quality. The maize silage DM and CP contents were 30.5 and 8%, respectively. Daily DM intake of the ox was signinficantly higher (P<0.01) for T4 (8.05kg/day). Higher (P<0.001) total nutrients intake other than ADF and ash were recorded in the T4. The daily body gain was higher (P<0.01) for T1 (1.09 kg) than all. This study noted the most feed efficient for animals fed on (T1) and did not recommend the replacement of hay by maize silage at more than 33% (T2) in terms of feed conversion ratio. Dressing percentage on slaughter basis was higher (P<0.001) for T1 (55.40%) than other treatment. The quality of beef based on Warner-Bratzler Shear Force test result, T1 and T4, T2, and T3 were categorized as tough, tender, and intermediate, respectively. Water holding capacity was significantly good (P<0.05) for T2 and T3 as compared to T1 and T4, however, no change in the pHu. The net return was higher for T1. Therefore, it could be concluded that the inclusion of maize silage up to 33% (T2) could be confirmed for better performance, feed conversion efficiency, carcass and meat quality parameters in the feeding of fattening oxen. Hence, further study is recommended to verify the optimal level of maize silage inclusion in the diet of beef fattening and also evaluate its effect on beef sensory attributes and fatty acid profiles
