حسین شادمان - گروه علوم دامی، دانشکده کشاورزی، دانشگاه زنجان، زنجان، ایران
احسان محجوبی - گروه علوم دامی، دانشکده کشاورزی، دانشگاه زنجان، زنجان، ایران
داود زحمتکش - دانشگاه زنجان گروه علوم دامی
مهدی حسین یزدی - دانشگاه اراک، دانشکده کشاورزی و منابع طبیعی، گروه علوم دامی

To predict body composition of growing Afshari fat-tailed lambs using the ۹-۱۱th rib composition as a predictor of whole body composition, ۱۰ lambs were randomly selected (۴۳.۹ ± ۳.۹; mean shrunk body weight; mean ± SD) and harvested accordingly. After slaughter, the ۹-۱۱th rib sections were harvested from chilled carcasses for ۲۴ h; fat, lean, fat-tail and bone were weighted separately and total separable fat (without fat-tail) and lean were grounded twice to obtain a homogenous sample for further chemical analysis. Rib dissection separable lean, fat and bone percent were (mean ± SD) ۳۳.۹ ± ۶.۶, ۲۳.۶ ± ۶.۶, and ۱۷.۳ ± ۷.۴, respectively. In addition, rib dissection ether extract, crude protein, moisture, and ash percent were (mean ± SD) ۲۷.۶ ± ۴.۱, ۱۹.۳ ± ۰.۷, ۴۹.۶ ± ۵.۳, and ۱.۷ ± ۰.۳, respectively. Except for carcass separable bone percent (with and without fat-tail), it was shown that the ۹-۱۱th physical rib composition can properly predict the carcass separable fat (adjusted R۲ of ۰.۶۲ and ۰.۸۶ with and without accounting for fat-tail, respectively; P < ۰.۰۱) and lean (adjusted R۲ ۰.۷۷ and ۰.۷۱ with and without accounting for fat-tail, respectively; P < ۰.۰۱). As for the carcass chemical composition, with or without accounting for fat-tail, none of rib chemical commotion based on as-is analysis predicted chemical carcass composition. However, when as-is data were represented as soft tissue dry matter, only rib crude protein (%, without accounting for fat-tail) could predict carcass crude protein (adjusted R۲ = ۰.۶۰; P < ۰.۰۰۵). In general, our results for the first time in fat-tailed sheep, showed that the ۹-۱۱th rib section can only predict physical, but not chemical, composition of fat-tailed lamb carcass.

carcass composition,, equation,, fat-tailed sheep,, the ۹-۱۱th rib section