Barnett, J. L., Hemsworth, P. H., Winfield, C. G. et al. 1987. The effects of pregnancy and parity number on behavioural and physiological responses related to the welfare status of individual and group-housed pigs. Applied Animal Behaviour Science 17, 229-243.
Pigs housed in tether stalls showed immunosuppression suggesting that their welfare was impaired. It was concluded that unresolved aggression in tether-housed pigs may result in a chronic stress response.
Year
1987