Associations between lying-down behaviour problems and body condition, limb disorders and skin lesions of lactating sows housed in farrowing crates in commercial sow herds

Health problems, difficulties in lying down and skin lesions are relevant indicators of poor welfare in sows confined in farrowing crates. This study investigated limb disorders, injuries, body condition and lying-down behaviour in 10 commercial sow herds. Five hundred seventy lactating sows were examined clinically, and 555 sows were further observed when lying down. Forty-one percent of the sows showed some difficulties in lying down and 15% were lame. Skin lesions were most frequently observed on lateral hind feet or shoulders, each in approximately 20% of the sows. The data were analysed for conditional associations among the parameters applying hierarchical log-linear models for contingency tables. Slipping and interruptions while lying down were associated (P<0.05), but other difficulties in lying down were conditionally independent within the herd. Shoulder wounds were more common in thin or lame sows (odds ratio 5.5 and 2.5, respectively), and lameness was further related to hock lesions (OR 11.9, severely lame sows), hind feet lesions (OR 2.5–4.3 depending on the severity of lameness) and uncontrolled lying-down behaviour (OR 1.8–5.8). Fat sows were more likely to show stepping behaviour when lying down (OR 2.7), slipping was associated with hind feet lesions (OR 2.2) and overgrown hooves were associated with abnormal lying-down behaviour (OR 11.5). The specific difficulties in lying down may provide relevant support for the clinical findings.