Genetic analysis of milk producing efficiency traits in crossbred cattle

Data on first lactation milk yield/day of first lactation period, first lactation milk yield/day of age at first calving, life time milk yield/day of life time lactation period and life time milk yield/day of total age at calving of 393 animals of 6 genetic groups (Sahiwal, Rathi x Jersey, Sahiwal x Jersey, Sahiwal x Holstein Friesian, Sahiwal x Red Dane and Sahiwal x Jersey x Holstein Friesian) available from Livestock Research Centre of the University over 30 years ( 1970 - 1999) were analyzed. The averages for these traits were 7.53 +/- 0.33 kg, 2.23 +/- 0.10 kg, 8.12 +/- 0.18 kg and 1.73 +/- 0.05 kg respectively. Genetic group and period had significant effect on all the traits. However, effect due to season was significant on First lactation milk yield/day of first lactation period and lifetime lactation yield/day of lifetime lactation period. The heritability estimates for these traits were 0.546 +/- 0.19, 0.763 +/- 0.22, 0.678 +/- 0.28 and 0.367 +/- 0.27 respectively. The genotypic and phenotypic correlations were highly positive and significant. It may be concluded that the performance of Sahiwal x Jersey, Rathi x Jersey, Sahiwal x Holstein Friesian and Sahiwal x Red Dane were better than the Sahiwal and triple crosses under the present study.