Effect of persistency on milk yield under organised farm management condition

Abstract

The evaluation of 255 Tharparkar cows having 887 records spread over a period of 15 years and 9 parities were done for production and reproduction traits by using least-squares analysis. The overall mean of persistency was 0.71± 0.006. Season of calving and period x season interaction were significant (P<0.01) on persistency whereas, the effect of parity was non significant. The effect of peak yield (as co-variable) was significant on persistency and that of calving interval as nonsignificant on this trait. The phenotypic correlations of persistency with milk yield and lactation length were positive and significant while they were negative and significant with peak yield, wet average and total digestible nutrients intake.