The Effect of Different Levels of Feeding in Late Gestation on Ewe Weight, Lamb Birth Weight and Lamb Growth of Karakas and Hamdani Ewes

Abstract

This study was conducted to investigate the effect of different feeding levels on ewe weight gain, deviation in weight gain, lamb birth weight and lamb growth performance of Karakas and Hamdani breeds. The ewes were devided into 4 groups; the first, second, third and fourth groups had 80, 100, 115 and 130 % of the NRC recommendation for 60 kg late gestation, respectively, The mean deviation of ewe live weight in late gestation and in postpartum were 0.39 and -5.80 kg, 9.09 and 2.97 kg, 11.95 and 5.26 kg, 14.29 and 7.53 kg for groups 1, 2, 3 and 4, respectively. The first group had significantly lower (P<0.01) deviation than other groups. Ewe live weight gain was significantly (P<0.01) increased by increasing the other groups. Ewe live weight gain was significantly (P<0.01) increased by increasing the nutrient percentage. Ewe age and genotype did not affect deviations in late gestation live weight or postpartum live weight. The mean lamb birth weights were 3.97, 4.15, 4.02 and 4.56 kg for groups 1, 2, 3 and 4, respectively The 4th group had significantly higher (P<0.01) birth weight than the other groups. The mean lamb weightson day 28 were 8.44, 9.55, 9.39 and 9.31 kg for groups 1, 2, 3 and 4, respectively. While the first group of lambs exhibited significantly lower live weights on day 28, the live weights of lambs on weaning were 21.90, 22.20, 20.88 and 20.16 kg for groups 1,2, 3 and 4 respectively. While the effect of genotype on lamb birth weight was significant (P<0.01), it had no significant on the other characteristics. Birth type had a significant (P<0.01) effect on lamb weight gain in different periods, but the effect of sex was not significant.