Risk factors for prolonged postparturient vaginal discharge in sows

Abstract

Previous study has shown that excessive postparturient vaginal discharge in sows causes impaired reproductive performance in the subsequent litter. This observational study aimed to investigate the effects of categorical predictors (farm (1-7), assisted farrowing, parity number (1, 2-5, >5) and stillbirth) and continuous predictors (farrowing duration, litter size and postparturient body temperature) on the incidence of prolonged postparturient vaginal discharge (duration of postparturient vaginal discharge >5 days) in sows. Data was collected from 620 postparturient sows raised on 7 farms in 4 provinces in Vietnam. Univariate logistic regression analysis was used to identify the potential risk factors for prolonged postparturient vaginal discharge. All risk factors that had a P-value <0.15 in the univariate analysis were selected for multivariate logistic regression analysis. The average farrowing duration, litter size, incidence of stillbirth at litter level and incidence of assisted farrowing were 4.0±1.7 h, 12.1±2.9, 39.4% and 32.9%, respective ly. The duration of postparturient vaginal discharge was 4.3±0.9 days. The incidence of prolonged postparturient vaginal discharge was 12.6% (78/620). Multivariate logistic regression analysis revealed that the risk factors for prolonged postparturient vaginal discharge were assisted farrowing (RR=2.40, P<0.001), increased farrowing duration (RR=1.17, P=0.038), parity >5 (RR=2.57, P=0.001) and stillbirth (RR=1.93, P=0.009). In conclusion, prolonged postparturient vaginal discharge was common in sows. Assisted farrowing, increased farrowing duration, parity >5 and stillbirth were risk factors for prolonged postparturient vaginal discharge.