Effect of Dietary Enrichment with Copper and Zinc Along with Additional Energy during Periparturient Period on Ovarian Steroids and Reproductive Performance in the Crossbred Cattle

The study was conducted to evaluate the effect of copper and zinc along with additional energy on steroid hormone and reproductive performance during periparturient period in crossbred cattle.Advanced pregnant crossbred cows (n=20) of 2 to 4 parity and lactation yield of >10L/day were divided into two equal groups (n=10 cows/group).In Group I the cows were supplemented with copper (15.7/kgDM), zinc (22 mg/kg DM) and increased energy allowance in the form of 20% additional concentrate, Group II cows were fed with only basal diet.Copper and zinc were supplemented with wheat flour bolus from 4 before to 8 week after calving whereas energy allowance was increased from 2 to 8 week after calving on daily basis to individual animal.Blood samples were collected to determine estradiol (E 2 ) and progesterone (P 4 ) in the serum using RIA.Postpartum reproductive performance was assessed in terms of calving to conception interval, pregnancy rate and number of service per conception.Serum E 2 increased significantly at 1 st week of prepartum, day of calving, 1,2,3,6,7 and 8 weeks postpartum in Group I as compared to Group II.Further, Serum P 4 level increased significantly from 2 nd week of prepartum, 4,5,6, and 7 weeks postpartum in Group I than that of Group II.Marked improvement in the fertility was recorded in terms of reduced calving to conception interval, service per conception.