Abstract

    A total of 32 Sahiwal cows in the last trimester of pregnancy were used to determine the effect of different immunopotentiators on their postpartum reproductive performance. The cows were divided into four groups. Group-1 served as untreated control, while groups 2, 3 and 4 were treated with levamisole hydrochloride (0.5 mg/Kg body weight orally), vitamin E-selenium (10 ml intramuscularly per cow) and BCG vaccine (0.5 ml subcutaneously per cow), respectively. These immunopotentiators were given twice with one week interval at about 60 days prior to expected date of calving. Various reproductive parameters during subsequent postpartum period, i.e., placental expulsion period (hours), uterine involution period (days), postpartum estrus interval (days), number of services per conception and service period (days) were studied. It was noted that duration of all these parameters (mean ± SE) were longest in cows of untreated control group (10.56 ± 0.57, 52.38 ± 1.38, 125.38 ± 25.79, 2.63 ± 0.50 and 286.88 ± 39.04, respectively) and shortest in the cows of vitamin-E selenium treated group (8.88 ± 0.30, 31.13 ± 0.52, 70.00 ± 15.92, 1.50 ± 0.19 and 115.00 ± 19.75, respectively). Two reproductive parameters, i.e., postpartum estrus interval and number of services per conception were non-significantly lesser in the cows of treated groups as compared to those of untreated control. Three reproductive parameters, i.e., placental expulsion period, uterine involution period and service period were reduced significantly (p<0,05) in vitamin-E selenium and BCG treated groups as compared to control. The cows of levamisole hydrochloride treated group showed significant (p<0.05) reduction only in uterine involution period as compared to untreated control. All the treated groups differed non-significantly amongst each other for all reproductive parameters except uterine involution period.