Reproductive efficiency in terms of fertility, Prolificacy and survival rate are considered the major components of overall efficiency in sheep productivity. While fertility of Awassi ewes is moderate to high depending on feeding and management practices, however, litter size is low and Awassi is not considered a prolific breed. Heritability estimates of these traits are rather low, and reflect small genetic variation in these traits. The possible avenues for increasing reproductive capacity environmentally and genetically are discussed in the text of this review article.

No abstract

At the Sheep Breeding Station, IPA Agricultural Research Center, milk production was investigated in 92 Iraq Awassi (AW) and 95 Assaf x Awassi (AA) ewes under accelerated lambing system , together with effects of age and body weight of ewe , lambing season and sex by litter size of lamb using General Linear Model (GLM) procedure . The overall means of milk yield and lactation period were 85.64 kg and 132.36 days, respectively. AA ewes surpassed significantly AW ewes in milk yield (99.15 vs. 74.99 kg) and lactation period (139.0 vs.126.8 days).Age, weight of dam at lambing and sex by type of birth of lamb had significant effects on milk yield. Milk produced by ewes lambed at first season was significantly higher than ewes lambed during second and third season.

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.