Abstract
Legesse, G., Abebe, G. and Goetsch, A.L. 2006. Performance and harvest measures of Somali and Arsi-Bale goats managed under three feeding systems in Ethiopia. J. Appl. Anim. Res., 30: 5–12.
Forty-eight intact male goats, approximately 9 months of age, were used in an 84-day experiment to determine effects and interactions of genotype [27 Arsi-Bale and 21 Somali, with mean initial body weight (BW) of 14.1 and 15.9 kg, respectively (SE=0.39)] and feeding system (intensive, semi-intensive and extensive) on growth performance and harvest measures. Goats on the intensive (I) treatment were confined in individual pens and fed Rhodesgrass hay supplemented with 300 g/day (air-dry) of a concentrate mixture; semi-intensive (S) goats grazed grass pasture for 7 h/day and were supplemented with 300 g/day of concentrate; and goats on the extensive (E) treatment grazed grass pasture for 8 h daily. There were no significant interactions between genotype and feeding system. Average daily gain (ADG) ranked (P<0.05) S > I > E (54, 32, and 5 g) and was greater (P<0.06) for Somali than for Arsi-Bale goats (34 vs 27 g). Hot carcass dressing percentage among feeding systems was lowest (P<0.05) for E (42.6, 43.3 and 38.8% for I, S and E, respectively). Carcasses of Somali goats were lower (P<0.05) in separable lean tissue (55.3 vs 58.9%) and higher in fat (P<0.05; 14.0 vs 11.0%) compared with Arsi-Bale carcasses. Carcass separable lean concentration ranked (P<0.05) S (62.2%) > I (57.5%) > E (51.6%), fat among feeding systems was greatest (P<0.05) for I (15.3, 11.2 and 10.9% for I, S and E, respectively) and bone was greatest (P<0.05) for E (27.3, 26.6 and 37.5% for I, S and E, respectively). In conclusion, ADG of male Somali and Arsi-Bale goats was similarly affected by the different feeding systems, with Somali goats yielding greater final BW than Arsi-Bale as a function of both greater initial BW and ADG during the experiment. Feeding system can impact not only growth performance but also carcass characteristics that may influence consumer appeal.