Growth Rate of Carcass, Non-carcass and Chemical Components of Restricted Fed and Realimented Growing Lambs

This study aims to determine the impacts of feed restriction and refeeding on the growth rates of carcass tissues and non-carcass components in lambs A total of 48 Najdi male lambs, of an average body weight 26.6 +/- 0.3 kg and approximately 3.5 months old, were used for this study. Significant (P<0.05) decreases in the daily weight gain of empty body, cold carcass, liver, empty stomach compartments, empty intestines, internal fats, subcutaneous fat, intermuscular fat, and separable lean were detected when the two feed restriction levels (25% and 40%) were imposed compared to the ad libitum fed group. Also, feed restriction levels significantly (P<0.05) decreased the daily accretion rate of fat, protein and moisture contents of the separable lean. In contrast, the daily weight gain of empty body, liver, empty intestines and internal fats of the feed restriction groups were significantly (P<0.05) higher than those values obtained from the ad libitum control group during the realimentation phase; whereas, lambs that moved from 40% feed restriction to ad libitum feeding had significantly (P<0.05) lower average daily deposition rates for all studied carcass tissues than control lambs Liver and empty intestines were the fastest non-carcass components to compensate by realimentation. During the realimentation phase, average daily accretion rate of moisture and protein continued to be significantly (P<0.05) slower, while the accretion rate of chemical fat was higher (P<0.05) in the lambs that had been fed the 25% or 40% feed restriction levels than the control lambs. (c) 2013 Friends Science Publishers