Genetic analysis of milk producing efficiency traits in crossbred cattle

Abstract

Data on first lactation milk yield/day of first lactiation 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 of total age at calving of 393animals of 6 genetic groups (Sahiwal, Rathi x Jersey, Sahiwal x Jersey. Sahiwal x Holstein Friesian, Sahiwalx Red Dane and Sahiwal x Jersey x Holstein Friesian) available from Livestock Research Centre of the University over 30 years (1970 - 1990) were analyzed. The averages for these traits were 7.53±0.33 kg. 2.23±O.10 kg, 8.12±0.18 kgand 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 waits 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, 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.