Genetic analysis of Lactation traits of Jersey Crossbred Cattle

Abstract

Data on 305 days milk yield, total lactation milk yield, lactation length and peak yield of Jersey crossbred animals available from organized herd of Eastern Regional Station of ICAR- National Dairy Research Institute, Kalyani, Nadia, West Bengal over 29 years (1986-2014) were analyzed to determine the effects of important environmental factors on lactation traits and their genetic control. The least-squares means of 305-days milk yield, total milk yield and peak yield were 2141.26±79.32, 2496.14±82.57 and 11.89±0.28Kg, respectively with an average lactation length of 337.73±6.9 days. The data were grouped into different classes according to season of calving, period of calving, parity and genetic group of animals. The random effect of sire had significant (P<0.01) influence on all lactation traits considered in the present study. The season of calving significantly (P<0.01) affected all traits except lactation length. Period of calving and genetic group of animal also significantly influenced all the considered traits. The heritability estimates of all lactation traits under study were high in magnitude, ranging from 0.39 to 0.58 except lactation length (0.15), which indicates genetic progress is possible through selection for these traits.