Effect of Body Condition Score, live weight and age on reproductive performance of Afshari ewes.

摘要

Effect of Body Condition Score (BCS), ewe live weight and age at mating were studied on reproductive performance of Afshari ewes. Total 162 Afshari ewes divided in four BCS Group (2, 2.5, 3 and more than 3.5). Reproductive parameters, such as number of Lambs born per joined ewes, kilograms (kg) lambs born per joined ewes, gestation period and birth weight of lambs were determined. Obtained results from present study showed that, the BCS had a significant effect on lambs born per joined ewes (p<0.05). In BCS=3 reproductive performance was better and heavier lambs (kg) were born. While the lambing rate in ewes with BCS>3.5 declined. Estrus cycle in ewes with BCS=3 was normal, while in ewes with BCS 2 and 2.5, estrous cycle duration was shorter and more irregular. Number of lambs born per lambing in ewes with 74 to 80 kg weighing was higher. Effect of BCS and ewes weight on weaning weight was very significant (p<0.001) and followed by ewes weight increases, lambs weaning weight increased. Effect of ewe age on pregnancy period was significant (p<0.05). Ewes with two years old age had lower gestation period and this factor in eight years old ewes was highest. Results revealed, the importance of BCS on lambs born per joined ewes, lambing rates, positive effect of ewe weight on the number of lambs born per lambing and the impact of age on pregnancy period.