Authors: PERVEZ AKHTAR, SAFDAR ALI, ASGHAR HUSSAIN, MUHAMMAD A. MIRZA, MUHAMMAD IQBAL MUSTAFA, JAVED IQBAL SULTAN
Abstract: Data obtained from 5260 birth records of 1179 Hissardale sheep maintained at the Livestock Experiment Station, Jahangirabad, in the district of Khanewal during 1978-1995 were analyzed. The objective was to evaluate the performance and to estimate the heritability of Hissardale sheep in Pakistan. Mean 180-day, 270-day, and yearling weights were 23.5 ± 3.31 kg, 25.7 ± 3.49 kg, and 30.7 ± 3.83 kg, respectively. Mean greasy fleece weight was 3.6 ± 0.57 kg. Post-weaning mean daily weight gain was 45 ± 0.02 g. Mean weight at first service was 38.9 ± 4.9 kg. The number of services per conception averaged 1.23 ± 0.40. The sire model using PROC MIXED in SAS was used to estimate heritability. Heritability estimates for 180-day, 270-day, and yearling weights were 0.09 ± 0.03, 0.17 ± 0.04, and 0.15 ± 0.04, respectively. The heritability estimate of post-weaning average daily gain was low (0.06 ± 0.03). The heritability for greasy fleece weight was also very low (0.02 ± 0.02). Low estimates of heritability indicated the presence of less additive genetic variance and large environmental variance. Hence, improvement in the traits through selection may be limited.
Keywords: Heritability estimates, post-weaning growth, Hissardale sheep, Pakistan
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