Sixteen weaned (3.5-4 months) entire male lambs from each of Awassi and Karadi were weighed and randomly divided equally into two groups to receive concentrate (16% crude protein and 2769 kcal energy) either ad libitum or 3% of their body weights, and to be slaughtered at 36 or 44 kg. Results revealed that overall means of daily gain in weight, dressing percentage based on slaughter and empty body weight, rib eye area and fat thickness were 0.258±0.01 kg, 46.54± 0.49%, 54.35 ± 0.40%, 14.98 ±0.44 cm2 and 2.86 ± 0.12 mm, respectively. It seems that Awassi lambs significantly surpass Karadi lambs in dressing percentage based on slaughter weight and had thicker subcutaneous fat, only. Also, lambs fed ad lib excell significantly those lambs fed 3% in daily gain in weight, dressing percentage based on slaughter weight, and fat thickness. Lambs slaughtered at 44 kg had significantly higher dressing percentage, rib eye area and fat thickness.

A total of 32 weaned (3.5-4 months) of Awassi (16) and Karadi (16) lambs were randomly allocated into two equal groups to be fed either ad libitum or 3% of their body weight concentrate, and to be slaughtered at 36 and 44 kg body weight. After chilling at 40c for 24h, the carcass was split along the vertebral column into two halves by electric saw, and the left side was separated into eight whole sale cuts and were physically dissected into lean, fat and bone and weighed. Results reveal that the overall mean of lean, fat, bone, lean: fat and lean: bone ratio were 60.31±0.25%, 17.05± 0.69%, 22.63 ± 0.59%, 3.78 ±0.20 and 2.71 ± 0.06, respectively. It was noticed that Karadi lambs surpass significantly (P<0.01) Awassi lambs in the content of lean (61.32±0.29 vs. 59.30±0.21%) and bone (24.72±0.85 vs. 20.53±0.35%) and had lower content of fat (13.94±0.75 vs. 20.15±0.39%). Neither lambs fed ad libitum nor 3% concentrate had a significant effect on composition of the carcasses. Lambs slaughtered at 44 kg had significantly (P<0.01) higher content of fat and lower bone content. Awassi lambs and those slaughtered at 44 kg had significantly (P<0.01) higher total body fat than did Karadi lambs and those slaughtered at 36 kg.

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Twelve new born Karadi lambs were docked within 3 days of their birth using rubber-rings, and left with their mothers till weaning (2.5 months). Another 12 weaned Karadi lambs obtained from local market were left intact. Following an adaptation period of a week, the docked and intact lambs with an average initial weight of 16.83±1.522 and 19.92± 0.748kg were randomly divided into three equal groups to be slaughtered at 20, 30 and 40kg. Results revealed that overall means of daily gain in weight, dressing percentage based on slaughter and empty body weight, rib eye area and fat thickness were 0.261±0.014kg, 45.956±0.428%, 53.933±0.678%, 11.288±0.488cm2 and 2.023±0.76mm, respectively, and no significant difference exist between them except dressing percentage based on empty body weight. It appears that carcasses of intact lambs compared to docked lambs contained significantly higher lean (62.79 vs. 59.85%), lean: fat (5.319 vs. 4.142), lean: bone (2.772 vs. 2.489) and numerically lower fat (16.058 vs. 14.042%) and bone (23.172 vs. 24.096%). Also, it was noticed as slaughter weight increase, there is an increase in dressing percentage, rib eye area, fat thickness, fat content of their carcass with a lower proportion of lean and bone.