The effect of ewe body condition score at mating on lamb body weights and litter size in purebred and crossbred Zel sheep

The aim of current study was to investigate the effect of ewe’s body condition score on lamb body weights and litter size in Zel sheep. For this purpose, body condition scores of 132 ewes (50 purebred Zel ewes and 82 crossbred of Zel and Dalagh ewes) which ranged from 2 to 4 years and 34.5 to 63.5 kg were used. Body condition scores of ewes were recorded at mating. Ewes were divided into five groups with a distance of 1 unit (from 1 to 5) based on BCS. Ewes with the cores of 3 and 5 had the highest and lowest frequencies in the population, respectively. Purebred and crossbred lambs showed significant differences in body weights (from birth to weaning time) and litter size. Crossbred lambs showed higher weights at the all ages (P<0.05) and more litter size in comparison with purebred lambs. Body condition scores of ewes showed a significant effect on lambs’ body weights and litter size. Lambs of ewes with BCS 4 and 5 showed more body weights from birth to weaning. The highest rate of twinning was recorded in ewes with BCS 3 and higher. These results suggested that ewes with at the least 3 body condition scores had better productive and reproductive performance in Zel breed.