EFFECT OF PREPARTUM TREATMENT OF VITAMIN E-SELENIUM ON POSTPARTUM REPRODUCTIVE AND PRODUCTIVE PERFORMANCE OF EXOTIC COWS AND THEIR CALVES UNDER SUBTROPICAL CONDITIONS

This study was carried out at the Livestock Experiment Station, Bhunikey (Pattoki), District Kasur, Pakistan. Forty exotic cows (20 each of Holstein Friesian and Jersey breed) in their last trimester of pregnancy were randomly selected. These cows were divided into two equal groups. Animals of group-I served as control and were injected with 20 ml sterile normal saline intramuscularly, while each cow in group-II was treated with vitamin E-selenium (vitamin E acetate 50.0 mg and sodium selenite 0.5 mg/ml) twice (20 ml at each time) with one-week interval. First injection was given at about 40-60 days prior to the expected date of calving. Calves born to the experimental cows were monitored to study the carry over effect of treatment, if any, from dams to the calves. The reproductive parameters, viz. placental expulsion period, uterine involution period, postpartum insemination interval, service period and number of services per conception in the cows of treated group were significantly (P<0.05) lesser compared with those of the control group. However, the differences in production parameters, i.e., lactation milk yield, lactation length and wet average between the two groups were statistically non significant. The same was true for birth weight, weaning weight and growth rate upto weaning between calves of the two groups. In conclusion, it appears that administration of vitamin E-selenium before calving may be beneficial in improving the postpartum reproductive parameters in exotic cows. However, number of animals used in each group was too small to draw any definite conclusion. Key words: Vitamin-E, selenium, reproductive and productive performance, exotic cows, calves, subtropica