HABRI Central

Sows in an extensive setting maintain small, stable matrilineal social groups comprised of familiar, and often genetically related, conspecifics. Providing conditions in an intensive farm setting which allow similar social groups could reduce aggression by allowing familiar sows to benefit from an established dominance order. Given that aggression levels among breeding sows peak immediately following introduction to a group pen, this study used a 2 × 2 factorial design to evaluate whether the level of familiarity among a small cohort, or method of introduction into a larger dynamic pen influenced the occurrence of aggressive behavior involving newly introduced sows. Treatments included combinations of sows either premixed for seven days prior to pen introduction (PMIX) or having no contact prior to pen introduction (UMIX) and entering the pen alone (IND) or entering the pen as a batch (BAT). Sows were monitored by focal video for one hour after entering the pen. Analysis of aggressive events yielded a significant interaction between level of familiarity and method of introduction. Familiarity had no effect when sows entered the pen as individuals whereas UMIX BAT sows participated in the most aggressive events (46.7 ± 9.1) and PMIX BAT sows the fewest (10.5 ± 2.1; P 

Researchers should cite this work as follows:

1. Aggression
2. Animal welfare
3. Group housing
4. sows
5. Swine