Vol. 8, Issue 12 (2019)

Author(s):
AJ Shankare Gowda, TG Honnappa, CSNagaraju, M Devaraj and A Krishnaswamy

Abstract:
Evaluation of conception rate is the most important measure of herd fertility status. Available information on this aspect in a herd under Indian tropical climatic conditions is meager. Therefore, an investigation was undertaken to evaluate the impact of season on conception rate in Holstein-Friesian upgraded cows at an organized dairy farm. In view of statistical analysis, the whole calendar year was divided into four Seasons viz. Winter (Jan-Feb), Summer (Mar-May) south west monsoon (Jun-Sept) and northeast monsoon (Oct-Dec) seasons. The study revealed the overall conception rate of the herd to be 46.59 per cent (with an overall 2.14 inseminations per conception) while the conception rate for 1^st, 2^nd, 3^rd, 4^th, 5^th and 6^th inseminations were 26.65, 10.62, 4.28, 3.72, 1.02 and 0.27 per cent respectively. Thus one half of the total cows were settled with first service, while rest of those cows required more than one service to conceive. Further, significantly higher (P<0.05) conception rate was obtained during summer (32.57%) and south west monsoon (31.95%) season as compared to 18.46 and 17.01% conception rates obtained during north east monsoon and winter seasons, thus, indicated the effect of season on conception rate. The summer season witnessed significantly higher number of conception.