Abstract
Data on 4977 breeding records of 1530 Niti-Ravi buffaloes maintained at Livestock Experiment Station, Bahadurnagar (Okara) during 1939-85 were analyzed to study the effect of year and season of calving on service period and calving interval. The service period and calving interval averaged 217.03 + 2.79 and 522.72 2.66 days, respectively. The service period in different years and seasons varied significantly. The service period was the minimum (188 days) in buffaloes calving during spring. The calving interval also varied significantly due to year and season of calving. The average calving interval was the shortest (495 days) among the buffaloes calving during hot humid season and was the longest (585 days) among the buffaloes calving during spring season.
INTRODUCTION
The buffalo has been accused for late age at first calving and long calving interval resulting in reduced reproductive efficiency, calf crop and milk yield on lifetime basis. In order to curtail the unproductive period, reduction in the length of calving interval seems inevitable . Since this parameter appears to have low genetic variability and is considered to be mainly influenced by environmental factors, the present study was undertaken to determine the effect of year and season of calving on the service period and calving interval in Nili-Ravi buffaloes.
