Factors associated with prolonged farrowing duration in sows
The present study was conducted to investigate the effect of parity number, gestation length, litter size and average piglets’s birthweight on the prolonged farrowing duration (PFD, farrowing duration ≥5h) in sows. Data were collected from 981 sows raised at 17 farms in 6 provinces in the North of Vietnam. Univariate logistic regression models were used to analyze the effect of each single factor on PFD. Factors that had significant effect on PFD with a P value <0.1 was included in the multivariate logistic regression analyses. Results of univariate analyses showed that all of the four mentioned-above factors had significant effects on the PFD in sows. Multivariate analyses, however, revealed that parity number did not significantly influence the PFD in the studied sows. Sows with a gestation length of 113-115 days had a higher odds for PFD than those had a gestation lengh >115 days (OR=2.4, P=0.004). A litter size of 12-15 piglets reduced the risk for PFD in comparison with a litter size >15 piglets (OR=0.38, P=0.001). Also, an average piglets’s birthweight >1.7kg lowered the risk for PFD compared with an average piglets’s birthweight <1.3kg (OR=0.32, P=0.003). This study found that a gestation length of 113-115 days, a litter size >115 piglets and an average piglets’ birthweight <1.3kg are risk factors for PFD in the sows.
Nguyen Hoai Nam
FVM- Vietnam National University of Agriculture
Keywords: Sows, time of farrowing, influencing factors