Epidemiologic evaluation of decubital ulcers in farrowing sows

Objective - To define temporal patterns and risk factors for development of decubital ulcers over the tuber of the spine of the scapula (tuber) of lactating sows. Design - Prospective study. Animals - 147 late-gestation sows and gilts. Procedure - Females were examined for skin lesions over the tubers, and body condition score, depth of back fat, and depth of soft tissues over the tuber (tuber depth) were determined (day 0). On days 5, 12, 18, 40, 54, and 68, sows were examined for lesions over the tubers. Data on sow parity, date of farrowing, total number of pigs born/litter, and number of stillborn pigs/ litter were obtained from farm records. Results - Ulcers were recorded for 33 of 206 (16%) shoulders by day 5. Peak prevalence (99/206; 48% of shoulders) was on day 12, and all ulcers had resolved by day 68. Ulcers were more common on the right shoulder. Considerable resolution of ulcers was evident between days 12 and 18, when sows still were housed in farrowing crates. Parity and tuber depth were significantly associated with ulcers and ulcer severity (size) on day 12. Clinical Implications - Decubital ulcers in lactating sows are a multifactorial condition. Factors such as floor type are important, but other physiologic and behavioral factors of periparturient swine, including body weight, body condition and mobility of late-gestation animals, duration of farrowing, and patterns of recumbency and activity, appear to be important in the pathogenesis of lesions. Housing sows on hard floors is not a sufficient cause of decubital ulcers over the scapula.