Motivated for movement? Exercise and the gestation environment on sow performance and welfare

The societal concern regarding sow confinement has prompted multiple countries to move towards providing a greater freedom of movement to gestating sows. The 2014 Canadian Code of Practice for the Care and Handling of Pigs permits the operation of existing stall barns if bred female pigs are given access to periodic exercise. The objective of this thesis was to determine how strongly gestating female pigs are motivated for time out of their stall, and if providing periodic exercise can increase sow welfare and reduce stress in comparison to housing in stalls and groups throughout gestation. Chapter 3 compared gilt and sow motivation for movement and food using an operant panel. In Chapter 4, operant panel testing was used to compare motivation to exit the stall in sows at three levels of satiety achieved by feeding high fibre (HF) feed. Finally, the welfare (Chapter 5) and productivity (Chapter 6) of gestating sows receiving exercise (E; walking/running 160 m/week) vs sows housed in stalls (C) and groups (G) during pregnancy was evaluated. Chapter 3 found that both gilts and sows demonstrated that they were equally motivated to exit the stall, and sows were more motivated for food than gilts. Chapter 4 found that feed restricted sows were more motivated for movement than sows fed HF ad-lib, with sows receiving 50% of their ad-lib HF intake being intermediate. Chapter 5 found that G sows lay more, sat less and performed fewer stereotypies than C and E sows. Chapter 6 found that in parities 5-7 E and G sows had a greater number of liveborn than C sows. These results suggest that gestating female pigs are motivated for movement, and this motivation has a strong exploratory/foraging component. Group housing, but not periodic exercise improved sow comfort and reduced stress, as indicated by postures and stereotypies. Periodic exercise improved reproductive performance in older sows only. In conclusion, periodic exercise at a low level does not provide any welfare or production benefits. Whereas group housing was shown to better meet the needs of the sow than periodic exercise, and a transition to group-housing is advisable