Working boars are an often-overlooked group in pig welfare discussions. Their welfare is affected by housing conditions, social isolation and the demands of intensive reproductive management.
Boar welfare is constrained by the management requirement for individual housing that prevents uncontrolled mating. Unlike sows who can be managed in groups, boars are isolated because group housing causes severe fighting. This isolation imposes chronic social deprivation on an inherently social species. Boars in individual pens show high rates of stereotypic behaviour indicating frustration and boredom. The physical demands of natural service cause progressive joint and muscle wear that often results in lameness that is underreported and undertreated. Training boars positively for semen collection and providing appropriate mental stimulation within individual housing constraints partially mitigates but cannot eliminate the welfare cost of isolation.