Post-calving administration of uterine stimulants does not improve reproductive performance in dairy cows

Abstract

ABSTRACT:The aim of this study was to evaluate the effects of administration of oxytocin, in combination with dinoprost or ergometrin, after parturition on the occurrence of clinical endometritis and subsequent reproductive performance in dairy cows. The cows, without retained foetal membranes, were assigned to one of three groups. No treatment was performed in the control group (Group C, n = 229). However, intramuscular administrations of oxytocin (30 IU) on Days 1 and 2 post partum, in combination with dinoprost (25 mg, Group D, n = 123) or ergometrin (15 mg, Group E, n = 130) administered on Day 7 post partum, were performed in experimental groups. Vaginal discharge score (VDS, 1-5), uterine content score (UCS, 1-3) on Day14 to 21 post partum, number of treatment interventions (TI), proportion of non-treated cows (NT) because of endometritis, calving to first insemination interval (CI), first insemination conception rate (CR), and proportion of pregnant cows by Day 150 post partum (PC), were compared among groups. There was no significant difference among groups for any parameter. Average values were 2.08, 2.24 and 2.06 (VDS); 1.49, 1.51 and 1.45 (UCS); 0.86, 0.93 and 0.74 (TI); 59.4, 54.2 and 54.7% (NT); 73.9 ± 15.2, 75.4 ± 17 and 74.2 ± 17 days (CI); 41.4, 38.9 and 44.3% (CR); and 75.4, 77.7 and 80.5% (PC) for Groups C, D and E, respectively. There was no significant benefit of preventive administration of oxytocin, in combination with dinoprost or ergometrin, after parturition on reproductive performance in dairy cows.Keywords: cow; endometritis; oxytocin; dinoprost; ergometrin; reproductive parameters Abbreviations CI = calving to the first insemination interval, CR = first insemination conception rate, NT = non-treated cows, PC = proportion of pregnant cows by day 150 post partum, TI = treatment interventions, TMR = total mixed ration, UCS = uterine content score, VDS = vaginal discharge score