Vol. 8, Special Issue 8, Part O (2024)

Abstract: A normal healthy reproductive cycle in females include onset of early postpartum estrus, successful conception and a normal parturition. The number of services required for a successful conception determines the fertility status of a breeding herd and thus the overall breeding efficiency of a farm. A study was conducted in an organized dairy farm where five years data from 1996 to 2000 was statistically analysed. The overall incidence of the estrous cycle length of less than 17 days, 18 to 24, 25 to 35, 36 to 48 days and more than 48 days were estimated to be 5.61, 42.49, 13.80, 16.08 and 22.00 percent, respectively. The incidence of interservice intervals varied significantly (p<0.05). The difference in the incidence of normal cycles might be due to difference in breed, plane of nutrition, management and agroclimatic conditions. The period of two heats is a reflection of one heat missed or silent heat, but the possibility of embryonic death cannot be ruled out. Inadequate oestrus detection was an important factor for a high incidence of long returns obtained in this study.