Growth, body composition and carcass tissue distribution in goats of large and small sizes.

摘要

Growth, composition and distribution of carcass tissues in male and female Omani goats of large (Batina) and small (Dhofari) body sizes were compared. Goats had ad libitum access to rhodesgrass hay (8% CP) and a concentrate diet (16% CP) from weaning until slaughter at 11 or 18 kg body weights. Batina goats reached slaughter weights earlier than Dhofari goats (P<0.001) with males (maximum of 147 g/day) growing faster than females (maximum of 92 g/day). Dhofari goats had higher growth rates relativeto final body weight (P<0.05). Batina had higher proportions of head, skin, feet, lungs and trachea (P<0.001) than Dhofari goats in which males had higher proportions of the testes in the empty body (P<0.001). Dhofari goats had higher (P<0.01) dressingout percentage (DO) than Batina at 18 kg body weight (55-58% and 51-52%, respectively). Dhofari had higher total body fat (P<0.05), total non-carcass fat (P<0.001) and carcass muscle (P<0.05) but lower carcass bone (P<0.001) than Batina goats. Dhofari also had higher proportions of muscles in the proximal hind limb (P<0.001), around the spinal column (P<0.001) and abdominal wall (P<0.05) but lower proportions of muscles in the proximal forelimb (P<0.001), distal forelimb (P<0.001), muscles connecting forelimb to thorax (P<0.05), intrinsic muscles of neck and thorax (P<0.001) and total forequarter muscles (P<0.001) than Batina goats. Dhofari goats had higher proportions of bone in the forelimb than Batina goats. It is concluded that the smaller Dhofarigoat may be more efficient for meat production than the larger breeds like the Batina in Omani conditions.