Effect of mother’s age on body weight of lambs from birth to weaning in various strains of domestic sheep Pramenka

Abstract

This study has been conducted on the domestic sheep Pramenka that is a dominant breed in Serbia. The purpose is to determine the effects of mother?s age on suckling and growth of lambs, and to find out at which week the lambs are normally weaned. Research was carried out on 1800 lambs of four strains (Svrljiski, Pirotski, Sjeni?ki, Sarplaninski) of sheep Pramenka (450 lambs per strain) for body weight. The weight of lambs was measured at the time of birth, 30, 60 and 90 days after birth during three years of experiment (2011-2013). Obtained results refer to variability of body weight of lambs at the time of birth, 30, 60 and 90 days after birth depending on mother?s age within each of four strains of Pramenka sheep. At the time of birth, the highest average weight (3.79 kg) of lambs was found in second age group of Pirotska genotype, while the highest average weight in third age group was found in remaining three Svrljiska (3.91 kg), Sjeni?ka (3.74 kg) and Sarplaninska (3.97 kg) strain of Pramenka sheep. Thirty days after birth the highest average weight of lambs was found in the second age group of Pirotska genotype (9.36 kg), in the first age group in Svrljiska (9.89 kg), while the highest average weight in third age group was found in remaining two Sjeni?ka (9.51 kg) and Sarplaninska (9.41 kg) strain of Pramenka sheep. Sixty days after birth, the highest average weight of lambs was found in third age group of Pirotska genotype (15.85 kg), in second age group in Svrljiska (15.51 kg) and Sjeni?ka (15.50 kg) genotypes, while the highest average weight in first age group was found in Sarplaninska (14.45 kg) strain of Pramenka sheep. Ninety days after birth, the highest average weight of lambs was found in second age group of Pirotska (20.58 kg) and Sarplaninska (20.45 kg) genotype, while the highest average weight in first age group was found in Svrljiska (24.38 kg) and Sjeni?ka (23.76 kg) strain of Pramenka sheep. The variability in body weight of lambs at birth, as well at different stages of growth after weaning at early growth stages is influenced by direct maternal genotype, strains of Pramenka sheep and age of ewes.