Effects and interactions of origin of sheep in Ethiopia (Highland vs Lowland areas), feeding and lengths of rest and feeding on harvest measures

Abstract

Yearling sheep from Highland (Arsi-Bale, H) and Lowland (Black Head Ogaden, L) areas of Ethiopia were used to determine effects and interactions of animal origin, feeding and lengths of rest and feeding on harvest measures. Ten sheep of each origin were rested for 1, 2 or 3d after arrival at the abattoir and before slaughter with ad libitum availability of grass hay and water and an overnight fast preceding slaughter. Eighteen to 20 sheep of each origin were fed for 2, 4 or 6 weeks in length with ad libitum grass hay and a concentrate supplement at 220 g/day per animal. There was an interaction (P<0.05) between origin and the linear effect of feeding period length in average daily gain, with a much greater value for H-F2 compared with other treatments (209, 120, 125, 118, 90 and 113 g/day for H-F2, H-F4, H-F6, L-F2, L-F4 and L-F6, respectively). Hot carcass weight increased linearly with increasing length of rest (P<0.05), with a tendency (P<0.09) for greater change for H vs L animals and the effect (P<0.05) of feeding vs rest (8.09, 8.34, 8.73, 7.88, 8.19, 8.02, 9.08, 8.54, 9.13, 8.17, 8.03 and 8.57 kg for H-Rl, H-R2, H-R3, L-Rl, L-R2, L-R3, H-F2, H-F4, H-F6, L-F2, L-F4 and L-F6, respectively). Carcass pH or instrumental color did not change due to treatment. In conclusion, there is considerable opportunity to increase carcass weight of H by manipulating periods of rest after arrival at the abattoir and before slaughter longer than 1 day. Moreover, 2 weeks of feeding H sheep markedly increased carcass weight. © GSP, India.