Pigs have strong motivations to forage and root for food, and feeding system design significantly affects welfare through competition, satiety, and natural behaviour expression.
Feed restriction to control growth rate causes chronic hunger and frustration, expressed as stereotypic rooting behaviour on floors and pen-mates. Feeder competition in group housing causes injuries and welfare disparities between dominant and subordinate pigs. Feeding system design that allows simultaneous access for all pen occupants significantly improves welfare outcomes.