Study on effect of various non-genetic factors on performance traits of Murrah buffaloes

In this study, the data was collected on production traits of Murrah buffaloes w.r.t. 1 to 4 parities for the period of 25 years maintained at Directorate Livestock Farm, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana. The effect of non-genetic factors viz; period of calving, season of calving, age at first calving and parity on daily milk yield were found to be significant and subsequently data were corrected to study the comparison of various lactation curve models to define the shape of lactation curve and to develop a suitable lactation curve model for Murrah buffaloes. The data used in the study pertained to 517293 daily milk yield records pertaining to 1524 lactations of 644 Murrah buffaloes sired by 213 bulls. The analysis was done using SAS 9.3 Least squares analysis. The period of calving showed significant (P<0.01) effect on 305 MY, complete lactation milk yield (CLMY), peak yield, lactation length and service period. The season of calving showed significant (P<0.01) effect on peak yield, lactation length and service period. The age at first calving showed significant (P<0.05) effect on peak yield. The parity showed significant (P<0.01) effect on 305 MY, complete lactation milk yield (CLMY), peak yield, lactation length and service period.