Abstract
Repeatability estimates for lactation yield, peak milk yield, and days in milk were derived from 506 lactation records of 120 Tharparkar cows kept at the Livestock Experiment Station, Rakh Ghulaman, district Bhakkar, during the period 1965-1978. The repeatability estimates for lactation yield, peak milk yield and days in milk were 0.305 ± 0.03, 0.0329 ± 0.05 and 0.219 ± 0.05, respectively. The low repeatability estimates for the three traits suggested considerable effects of environment, therefore, the use of multiple lactation records was emphasized for selection of dairy animals.
