Harold Gonyou University of Saskatchewan

Publish Date: April 23, 2012

A common problem in group-housed gestating sows is aggression at mixing. Mixing-induced aggression can cause injuries to sows, such as skin lesions, vulva biting, and even lameness [1]. The initial aggression can also result in subordinate sows becoming fearful of further conflicts while attempting to obtain feed which leads to inadequate feed intake and poor body condition [2]. Poor body condition represents poor welfare. Mixing sows during the first few weeks after breeding may reduce pregnancy rate [3,4]. Reproduction failure and lameness can result in sows being culled, which reduces longevity of sows. So, management strategies are needed to minimize aggression at mixing thereby to enhance welfare and performance of group-housed gestating sows.