Reproductive performance of Nili-Ravi buffaloes kept under farm conditions in Pakistan

Record of 9300 buffalo heads was used to study the consequence of environmental factors on reproductive traits of nili-ravi buffaloes. the data was analyzed using different fixed effect models to identify the different environmental factors altering the reproductive performance. the averages for age at first calving was1685±9 days varied from 1604±14 days to 1792±20 days at livestock production research institute bahadurnagar and livestock experiment station chak katora,respectively. the calving interval was observed 501±2days with the range of 519±3 days and 491±4 days. the service period ranged from 264±3 days to 224±5 days with the average 240±2 days; whereas,the average services per conception and gestation period were 1.56±0.01 numbers and 308 days,respectively. the herd-year of calving,season of calving (birth) and parity significantly affected all the reproductive traits (p<0.05). overall phenotypic trend for age at first calving,calving interval and dry period increased by 1.6,0.9 and 0.5 days per year,respectively. no change in service period and services per conception was observed during this period. proper feeding,management and early heat detection of heifers reduced the age at first calving,number of services per conception and calving interval.