Estimation of breeding values and genetic trends in Sahiwal cattle in Pakistan
2002
Javed, K. (Research Inst. for Physiology of Animal Reproduction, Kasur (Pakistan)) | Abdullah, M. | Khan, M.A.
Data on 8948 performance records of Sahiwal cows kept at Livestock Experiment Station Jahangirabad (Khanewal) were used in the present investigation. The breeding values for various performance traits were estimated by using Restricted Maximum Likelihood (REML) procedure fitting Individual Animal Model. The estimated breeding values for age at first calving ranged from -91.71 to 93-76 days in cows. The corresponding values were from -66.16 to 70.90 days in sires. The estimated breeding value for first lactation milk yield ranged from -52.86 to 85.94 kg for cows and for sires the values were -43.43 to 98.64 kg. The estimated breeding values for milk yield considering all lactations in cows fluctuated between -334.96 to 756.17 kg. The corresponding values for sires were - 182.85 to 531.74 kg. The estimated breeding values for lifetime milk yield ranged from -1414.20 to 2612.38 kg in cows and -1146.73 to 3239.37 kg in sires. The estimated breeding values for lactation length were -20.29 to 21.84 days in cows and - 15.61 to 17.95 days in sires. The estimated breeding value for calving interval ranged from -68.50 to 53.94 days for sires and -72.95 to 78.35 days for cows. Almost no net genetic change in milk yield was observed in the present herd of Sahiwal cattle and during the last 58 years indicating inefficiently of the selection strategy.
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