The impact of the duration of retained placenta on postpartum diseases and culling rates in dairy cows / 대한수의학회지

The objective of this study was to evaluate the duration of retained placenta (RP) on postpartum diseases and culling in dairy cows. Data were collected from 456 Holstein cows between 2008 and 2010. RP (> or = 24 h after parturition) and postpartum diseases were diagnosed by farm managers and a veterinarian according to standardized definitions. The overall incidence rate of RP was 14.0%, and the incidence rate of RP with fourth and higher parity was two times that of cows having offspring for the first time. The duration of RP was 2 to 15 days with a mean of 6.8 days, except for cases of fourth and higher parity which had a mean of 10.5 days. A total of 63% of cows with RP had postpartum diseases. Among the cows diagnosed with RP, 23.4% developed metritis, and of those, 35.3% developed endometritis or pyometra. A total of 25% (n = 16) cows with RP were culled within 60 days in milk (DIM) and of those culled, 75% (n = 12) had postpartum diseases. These results suggest that RP increases the risk of postpartum diseases such as metritis and mastitis and is a culling hazard up to 60 DIM.

Risk factors for retained placenta and the effect of retained placenta on the occurrence of postpartum diseases and subsequent reproductive performance in dairy cows

The objectives of this study were to determine the risk factors for retained placenta by evaluating several reproductive factors in individual cows, and to determine the effects of retained placenta on the occurrence of postpartum diseases and subsequent reproductive performance in dairy herds. The health status, cow parity, calving, and breeding dates were recorded from 805 calvings in nine dairy herds from October 2000 to March 2004. We used logistic regression to evaluate the effects of these factors on the incidence of retained placenta. A stepwise procedure, used to obtain the appropriate model with alpha = 0.05, revealed that abnormal partus and gestation length were important risk factors for retained placenta. The occurrence of endometritis and metabolic disorders was greater (p<0.01) in the group with retained placentas than in the control group. The mean intervals from calving to first service and conception were prolonged (p<0.05) by 7 and 18 days, respectively, in the group with retained placentas compared to the control group. These results suggest that abnormal partus and gestation length are strongly correlated with the development of retained placenta, which increases the occurrence of postpartum diseases and subsequently decreases reproductive performance in dairy herds.