The use of oxytocin for the reduction of cow placental retention, and subsequent endometritis.

Oxytocin was administered to reduce incidence of retained placenta and uterine infections that could delay subsequent conception. Three hundred and fifty multiparous Friesian cows, each with spontaneous delivery of a single calf were divided randomly into two groups. Some (n = 175) were injected with 30 IU of oxytocin immediately after delivery and again 2-4 h later, while the remainder formed an untreated control group. The placental retention 24 h after parturition was 24.6% and 10.9% in control and treated animals respectively (P < 0.01). Endometritis occurred in 51.6% of the animals following placental retention as compared to 10.4% of those with normal expulsion of the fetal membranes (P < 0.001). A comparison of reproductive indices showed a statistically significant improvement of fertility in treated cows with the average interval from calving to conception being reduced from 124.4 d to 93.7 d (P < 0.0001).