Reproductive performance of Sahiwal and its F1 crossbreds with Jersey and Holstein-Friesian.

Age at first calving, inter-calving period, dry period and number of inseminations per conception were studied for Sahiwal and F1 crossbreds with Jersey and Holstein-Friesian in a herd of Dairy Farm, C.S. Azad University of Agriculture and Technology, Kanpur. Age at first calving in Sahiwal, Jersey x Sahiwal (J x S) and Holstien-Friesian x Sahiwal (H-F x S) crossbreds was 1215.82±10.15, 971.47±11.59 and 1021.48±14.45 days, respectively. The inter-calving period in the respective breeds group was 502.12±3.17, 444.97±4.96 and 453.64±4.32 days. The dry period was significantly less in the both crossbreds J x S (104.59±2.75 days) and H-F x S (113.64±3.45 days) compared to parental zebu breed (202.29±2.24 days). The average number of inseminations required per conception were 3.88± 0.07, 2.75±0.07 and 2.94±0.08 in Sahiwal, J x S and H-F x S crossbreds, respectively. The results further revealed that age at first calving is reduced significantly by introduction of exotic germplasm. Jersey crossbreds were better than Holstein-Friesian crossbreds in their reproductive performances.