A University of Minnesota study concluded that higher claw lesion scores in lame sows vs. non-lame sows occurred in group-housed sows with electronic sow feeders (ESF) compared to those in stalls.

There was also an increased chance that sows with overgrown claws would have higher scores for white line and vertical side wall lesions, which appeared to be a risk factor for lameness in both sow housing systems.

Lameness is considered an effective animal-based indicator of well-being in pigs, resulting in less-than-optimal breeding efficiency and culling prior to achieving peak production.

In this study, 233 sows in conventional gestation stalls were compared with 323 sows in group pens with electronic sow feeders at the University of Minnesota Southern Research and Outreach Center at Waseca, MN. Lesion scores in different claw areas in lateral and medial claws and in front and hind limbs of sows were compared. The claws were examined during Days 60-70 of gestation using a mechanical restraint.

Total lesion scores for a claw were determined by adding the lesion scores for various areas in the claw.

Sows were categorized as lame based on their willingness to support weight equally on all limbs.

Analysis of the data showed that group-housed sows had higher lesion scores in all claw areas than stall-housed sows.

Regardless of the housing configuration, the likelihood of lameness increased by 13, 20 and 17%, respectively, with every unit increase in scores for overgrown claws, total white line cracks and total vertical and horizontal side wall cracks.

Separate analysis for the housing systems indicated that the likelihood of lameness increased by 13% in ESF pens and 28% in stalls, for every unit increase in the total score for vertical and horizontal side wall cracks.

There were positive correlations for all lesions observed in different claw areas in an analysis of the 229 stall-housed sows.

Researchers: Sukumarannair S. Anil; Leena Anil; and John Deen, DVM, University of Minnesota-St. Paul; and Samuel Baidoo, University of Minnesota Southern Research and Outreach Center at Waseca. For more information, contact Deen by phone (612) 625-7784, fax (612) 625-1210 or e-mail deenx003@umn.edu.