Foot lesions in finishing pigs and their associations with the type of floor.

The associations between individual foot lesions and different types of floor were investigated in 4038 finishing pigs on 21 units. The overall prevalence of foot lesions was 93.8 per cent and the prevalence ranged from 79.4 per cent to 100 per cent on different units. Analysis showed that pigs kept on bedded floors, with either sparse or deep straw, had a lower prevalence of sole erosions, heel erosions and heel flaps and a higher prevalence of white line lesions, false sand cracks, wall separations and toe erosions than pigs kept on bare solid concrete floors. Partially slatted floors were associated with an increased prevalence of heel erosions, heel flaps, white line lesions, wall separations and false sand cracks, and totally slatted floors were associated with an increased prevalence of sole erosions and heel flaps.

The prevalence and risk factors associated with forelimb skin abrasions and sole bruising in preweaning piglets.

The presence of skin abrasions and sole bruising in 264 preweaning piglets (1-30 days old) from 13 breeding units in south west England was investigated in 1995. The mean prevalence of forelimb skin abrasions among the pigs on the study farms was 36% (range 0-59%) and sole bruising was 50% (range 0-95%). Skin abrasions were located on three aspects on the front limbs: the carpus, the metacarpus and the digit. Lesions occurred early in a piglet's life; the modal ages for sole bruising was 4 days and for skin abrasions were 5 and 10 days. The presence of skin abrasions on the front limbs was significantly associated with the presence of sole bruising on the front feet. Logistic regression indicated that part-concrete, part-round-mesh (OR 56.4) and part-concrete, part-metal-rods floors (OR 15.9) and exposed aggregate (OR 4.6) were associated with an increased odds of sole bruising while the presence of sparse straw (OR 0.12) or deep straw (OR 0.12) in the pen was associated with lower odds of sole bruising. The same floor type (part-concrete, part-round-mesh) was associated with increased odds of forelimb skin abrasions (OR 2.2). A worn floor surface where the solid adjoined the perforated area (OR 4.6) and the presence of sparse shavings (OR 1.7) were also associated with an increased risk of skin abrasions.

Prevalence and risk factors associated with adventitious bursitis in live growing and finishing pigs in south-west England.

The prevalence and risk factors associated with adventitious bursitis in 912 growing and finishing pigs, originating from 20 different housing systems in south-west England, were investigated in this study. The overall prevalence of bursal lesions was 63.4%. Bursae were seen at different aspects of the hock: lateroplantar, plantar, medial and point of the hock. The most frequently affected site was lateroplantar (54.4%) followed by plantar (12.5%), medial (2.0%) and finally the point of the hock (0.7%). There was no difference in the proportions of left and right hocks affected. Bursal lesions were seen in pigs from 8 to 28 weeks of age and prevalence increased with age. Also, the longer the period pigs spent in the pen, the more likely they were to have bursitis. After accounting for the effect of herd of origin, bedding which covered the whole pen (OR 0.11) or only the lying area (OR 0.29) was the most important factor which reduced the risk of bursitis. A wet slurry film in the dunging area (OR 1.67) and a difference between the solid area and the concrete slats greater than 3 cm (OR 3.11) were significantly associated with an increased risk of bursal lesions.

Adventitious bursitis of the hock in finishing pigs: prevalence, distribution and association with floor type and foot lesions.

The prevalence, severity and distribution of adventitious bursitis were estimated in 3989 finishing pigs from 21 units in south-west England. The overall prevalence of adventitious bursitis was 51.0 per cent and ranged from 10.1 to 84.0 per cent in the different units. Bursae were found on four different aspects of the hock: lateroplantar, plantar, medial and point of the hock (capped hock). The median severity of the bursae at all the different sites was mild (score 1). There was a large variation in the prevalence of different bursal lesions. Lateroplantar bursae (41.8 per cent) were the most prevalent followed by plantar (12.0 per cent), medial (4.8 per cent) and capped hock (3.7 per cent). There was a significant trend in the prevalence of bursitis with floor type; pigs kept on solid concrete floors with deep straw (> 10 cm) had the lowest risk of having bursitis, and the prevalence increased successively when the floors were solid concrete with sparse straw (< 10 cm), semi-slatted and fully slatted. There was a significant association between the presence of bursitis and foot lesions.

Prevalence and distribution of foot lesions in finishing pigs in south-west England.

This paper gives the first estimate of the prevalence and distribution of foot lesions in finishing pigs in the south-west of England for 33 years. It was based on the examination of 4038 finishing pigs from 21 units. There were 3727 out of 3974 (93.8 per cent) pigs with at least one foot lesion. The prevalence of different lesions was: toe erosion (33.0 per cent), sole erosion (62.1 per cent), heel erosion (13.0 per cent), heel flaps (14.4 per cent), white line lesions (55.4 per cent), false sand cracks (23.9 per cent) and wall separation (11.5 per cent). The hind feet were more commonly affected than the front feet, and on each foot the lateral digits were significantly more frequently affected than the medial digits. Sole erosions, heel flaps, wall separation and false sand cracks were more frequently observed on the lateral than the medial digit. Digits with sole erosions were significantly more likely to have heel flaps, white line lesions or false sand cracks than those without sole erosions. Furthermore, there was a within digit association between overgrown hooves and toe erosion. The effects of weightbearing, gait and environment on the development of foot lesions is discussed.