Studies on post- partun oestrum in cross bred cows

Abstract

The object of the study was to find out the various reproductive parameters that influence the onset of post – partum oestrus in cross bred cows. With this object in view, a detailed investigation was undertaken in a herd of 115 cross bred cows of Jersey x Sindhi and Jersey x Local breeds belonging to the University Livestock Farm of the Kerala Agricultural University, Mannuthy during the period from February 1978 to March, 1979. After parturition, they were grouped into normal and abnormal calvers based on the normalcy of calving. All the cows were stall fed and were under identical conditions of feeding and management. The observations made and inferences drawn are summarised below: There were significant variations in the cessation of lochial discharge, regression of pregnancy corpus luteum, period of uterine and vulval involution, onset of first and second ovulations and the post – partum oestrus interval between normal and abnormal parturitions. Duration of lochial discharge, regression of pregnancy corpus luteum and onset of first ovulation were found to be significantly influenced by the season of calving. Parity of the cow was found to influence the period of lochia, involutions of uterus and also the post – partum oestrus interval. Milk yield of the cow significantly influenced regression of pregnancy corpus luteum and vulval involution. However, the breed of the cow and sex and weight of calf were not found to have any significant effect on the reproductive parameters studied. An incidence of 13.4 per cent of aberrations of oestrum was also observed.