Genetic Studies and Development of Prediction Equations in  Jersey×Sahiwal and Holstein-Friesian×Sahiwal Half Breds

Singh, P. K.; Kumar, Dhirendra; Varma, S. K.

doi:2005.18.2.179

Article

Animal Breeding and Genetics

Asian-Australasian Journal of Animal Sciences 2005;18(2): 179-184.
https://doi.org/10.5713/ajas.2005.179 Published online April 21, 2005.

Genetic Studies and Development of Prediction Equations in Jersey×Sahiwal and Holstein-Friesian×Sahiwal Half Breds

P. K. Singh, Dhirendra Kumar, S. K. Varma

Abstract

First lactation records (174) of Jersey횞Sahiwal and Holstein Friesian횞Sahiwal half breds under 9 sires maintained at Chandra Shekher Azad University of Agriculture and Technology, Kanpur, Uttar Pradesh, India from 1975-1983, were used to estimate the genetic parameters and to predict herd life milk yield and average milk yield per day of herd life from first lactation traits. The traits included were: age at first calving, first service period, first lactation period, first calving interval, first lactation milk yield, milk yield per day of first calving interval, herd life milk yield, herd life and average milk yield per day of herd life. Most of the production and reproduction traits were found to have positive and significant correlations between them on genetic as well as phenotypic scales. Total twelve regression equations were fitted. The prediction equation of herd life milk yield in both the genetic groups showed linear relationship with AFC, FSP, FLP, FLMY and MY/DCI and was apparent and significant. Similarly, polynomials for milk yield per day of herd life for J횞S and HF횞S half breds also showed linear trend, which was found highly significant. The highest and lowest R2 values were found for FCI and AFC, respectively.

Keywords: Genetic Study; Prediction Equations; Jersey; Holstein-friesian; Sahiwal