Pantnagar Journal of Research

Abstract

Data for the present investigation were collected from a history sheet of crossbred cattle at the Instructional Dairy Farm of G. B. Pant University of Agriculture and Technology, Pantnagar. The data about 1000 crossbred cattle with a total of 3583 calving records from 87 sires were distributed over 32 years from 1988 to 2019. The estimated average percentages for various parameters, including abnormal births, sex ratio (percent male birth), mortality and culling of female calves up to the age of first calving (AFC), and replacement rate (based on female calf and total calf), were 6.0%, 52.33%, 14.80%, 17.53%, 67.67%, and 30.32% respectively. The effect of the FLMY (first lactation milk yield) group was found to be non-significant on abnormal births, overall mortality rate, overall female calf culling, and replacement rate based on the female calf basis. However, there was a significant effect of the FLMY group on the sex ratio and the replacement rate based on the total calf basis. The heritability estimates for abnormal birth, sex ratio, female calf mortality, female calf culling, replacement rate from total female calf basis, and replacement rate from total calf basis were reported as 0.18±0.011, 0.045±0.056, 0.15±0.019, 0.08±0.078, 0.35±0.071, and 0.05±0.085, respectively. The lower values of heritability suggest a higher influence of environmental factors on these traits. Therefore, the future selection of dairy cattle for replacement and its components will require a fully integrated and balanced breeding model