The Effect of Hoof Abnormalities on Sow Behavior Before and After Feeding When Housed in a Farrowing Stall

and Implications The objective of this study was to evaluate the effects of excessive toe growth, hoof cracks in the outer hoof wall, and length difference between the inside and outside toe of the hoof on sow behavior in mid-lactation. Sows were classified into three treatment groups and one control group. The treatment groups were 1) presence of cracks in the outer hoof wall 2) length differences between the inside and outer toe of the hoof and 3) excessive toe growth. Some sows had both toe size differences and cracks in the outer hoof wall (n = 23). Hoof abnormalities were categorized into 3 scores based on the severity of the lesion. Control sows spent 12.7 % (13.3 min) of the total time (105 min) standing and eating. Before feeding, control sows spent 1.2 % of time standing and eating Sows with overgrown hooves spent less time standing and eating as lesion severity increased when compared to control sows. Each increase in overgrown hoof lesion score was associated with sows spending 54 % less time standing Sows classified as having hoof cracks were observed to stand more and lay down less than control sows; however, this may have resulted from the inability to identify hoof lesions that caused pain. As a result, sows with hoof lesions that did not have pain were grouped with sows that had hoof lesions that caused pain and may have reduced the true effect of hoof lesions on behavior. In this study, sows that had differences in toe size were not associated with a deviation from the control sows.