EFFECT OF DIFFERENT DOSES OF SODIC CLOPROSTENOL AT POST-PARTUM PERIOD OF BEEF COWS

Abstract

Reestablishment of reproductive activity after parturition is dependent on two physiological processes, uterine involution and reestablishment of the ovarian luteal cyclic activity. Impaired or delayed uterine involution can affect ovarian activity. Prostaglandin F2a (PGF2a) has an important function in uterine involution. The use of PGF2a synthetic analogous in bovine postpartum, however, has been limited. The aim of this study was to compare the effect of two different doses of a racemic cloprostenol mixture (D+L-Cloprostenol) given in the postpartum period, on reproductive performance of crossbred beef cows. Beef cows with normal parturition were randomly distributed into three groups: G1(n=144), Control Group; G2 (n=145), 0.530mg of D+L-Cloprostenol, given IM at three to five days after parturition, and the G3 (n=145), 1.060 mg of D-Cloprostenol, in the same schedule of group 2. The following parameters evaluated were: services per conception (c²), days from parturition to first estrus, and open days (Tukey test). There was no difference in body score condition among groups at parturition or during postpartum period (P>0.05). There was also no difference in the number of services per conception. The average number of days from parturition to first estrus was 88.77 + 23.64ª; 77.59 + 26.95^b and 76.22 + 26.28^b, and the average number of open days open was 97.34±26.54ª, 86.38±28.81^b and 85.23±30.12^b for groups 1, 2 and 3, respectively (P<0.05). Regardless cloprostenol doses, the treatments anticipated the beginning of reproductive activity in more than 10 days. The treatment with sodic cloprostenol in the post-partum period of zebu beef cows is an alternative to reduce anestrous postpartum and open days.

KEYWORDS: bovine; prostaglandins; uterine involution.