Effects of day of farrowing induction and spontaneous versus induced farrowing on sow and suckling piglet performance

Results: Analysis 1: Gestation length (mean ± standard error) was 114.01 ± 0.08, 114.67 ± 0.08, and 115.19 ± 0.09 days for day 113, 114, and 116 groups, respectively; spontaneous farrowing occurred in 6.50%, 14.89%, and 80.83% of sows. There was no treatment effect on number born alive (NBA), mummies, stillborns, litter weaning weight, litter average daily gain, percentage litters receiving medical intervention once, piglet mortality, or percentage sows in estrus by day 7 post weaning. Percentage unsupervised piglets was greater (P = .001) in day 116 (64.8%) than day 113 sows (56.9%), and intermediate in day 114 sows. Analysis 2: Sows farrowing spontaneously had shorter gestation lengths (114.4 ± 0.09 days) than induced sows (114.7 ± 0.07 days; P = .01). Other sow and piglet parameters did not differ between induced and spontaneous sows.