Selection of elite murrah buffaloes based on association of production traits

The present study was conducted on lactation records of445 Murrah buffaloes of 171 sires from history cum pedigree sheets maintained at Directorate of Livestock Farms, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab from 2001 to 2016. The milk production traits included in the study were 305-day milk yield (305 MY), total lactation milk yield (TLMY), peak yield (PY), days to attain peak yield (DPY) and lactation length (LL). Normality parameters viz. skewness and kurtosis for the said variables were estimated from the data, followed by data transformation and estimation of genetic and phenotypic correlation coefficients. Based on the estimates of correlation coefficients regression analysis was performed for predicting 305 MY, LL and by considering PY and DPY as independent variables using both transformed and untransformed variables. Results indicated that TLMY had high and positive genetic correlation with 305 MY, LL and PY while non-significant low and negative genetic correlation was observed with DPY Highly significant correlation between PY, 305 MY and TLMY indicated the strong genetic association among them. The 305 MY, LL and TLMY were predicted from PY and DPY using stepwise multiple linear regression models. The results indicated that when two traits were considered together for prediction, PY and DPY were found to be significantly associated with 305 MY, LL and TLMY Hence, selection based on PY can be used as a better criterion for improvement of other performance traits through their correlated response in Murrah buffaloes.