Effects of group housing after weaning on sow welfare and sexual behavior

Abstract

This project compared the effects of grouping sows after weaning or within 2 d after insemination on sexual behavior, aggression, injuries, stress, and mating success. At weaning (d 0), 360 sows were housed in groups of 10 sows at 4.4 m2 per sow (group weaned [GpW]) or individual stalls (stall weaned [StW]), with 18 groups per treatment. Six days after weaning (d 6), 7 inseminated GpW sows were moved to pens at 2.1 m2 per sow and keeping acquainted sows, and simultaneously, groups of 7 inseminated StW sows were mixed at 2.1 m2 per sow. Group-weaned sows showed greater variation in the onset of estrus (P = 0.02) but not in the length of estrus compared to StW sows (P = 0.21), with 7% fewer Gp..