environmental factors affecting pre-weaning growth traits of hissardale sheep in pakistan

Performance data on Hissardale sheep maintained at Livestock Experiment Station, Jahangirabad, district Khanewal, during 1978-95 were analysed using Harvey's Mixed Model Least Squares and Maximum Likelihood computer programme. The objective was to evaluate the pre weaning growth performance of Hissardale sheep in Pakistan. The average birth weight was 4.0+0.51 kg which was significantly affected by year, season, type of birth, sex and age of the dam (P<0.01). The average 60- and 90-day weights were 11.5+2.13 and 15.5+3.06 kg, respectively, which were significantly affected by year of birth, type of birth and sex (P<0.01). The weaning weight of Hissardale lambs averaged 20.1+3.86 kg and was affected significantly by year of birth, season of birth and sex of the lamb (P<0.01). The effect of type of birth of the lamb and age of the dam on weaning weight was, however, non significant (p>0.05).