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Diseases of the locomotor system cause in intensively housed fattening and breeding pigs considerable financial loss due to reduced productivity or death. The purpose of this retrospective observational study was to investigate associations between specific farming factors (e.g. housing, breeding, feeding) and limb disorders. The data were collected in 180 farms with questionaires from veterinarians during their routine herd visits. No analysis of individual animals was performed; rather, random samples were taken from at least five pens each in the farrowing, weaning and rearing. An incidence of illness of about 25 % was taken to represent a herd health problem. The descriptive evaluation of the data revealed a wide range of housing methods in the individual farms. In the farrowing and we aned piglet phases, a total of ten different housing methods were used, with plastic, metal and concrete all being deployed. In the farrowing unit the most common type of housing was the partly slatted metal floor (33 %), in the weaning unit the fully slatted plastic floor ( 40 %). The rearing section only used concrete floors with the most common variant (60 %) beeing fully slatted concret floors. So-called regression trees were performed first to find out farm specific factors influencing limb disorders, and then multiple logistic regression was performed to estimate quantitative associations between factors and disorders.In the farrowing unit the piglets were examined when one week and the three weeks old for haematomas of the claws, limb abrasions and arthritis. The herd frequency of claw haematomas (76 %) and abrasions (47 %) was high in the first week of life, but declined significantly in the third week of life (6 % resp. 17 %). Arthritis
as a herd health problem occured only sporadically in the first (4 %) and in the third (1 % ) week of life. It was therefore not analyzed statistically, since no structure of the data was to be expected; the same also applies to haematomas of the claws in the third week of life. The occurence of haematoma in the first week was associated with slatted floors on general (fully slatted floor OR: 3.1; partly slatted floor: OR 8.2), particulary with fully slatted floors with slat widths of <or= 9 min (OR 5.9). The chance of limb abrasions in the first week in farms with fully slatted concrete floors was 35-times higher than in farms with fully slatted plastic floors. In the third week of life limb abrasions on partly slatted floors were linked to rough rung surface (OR 7,6).in the weaned piglets section, the animals were examined for overgrown claws, bursitis, limb deformity and arthritis. 55 % of the herds revealed a problem with overgrown claws, 65
% with bursitis and 24 % with limb deformities. Arthritis only occure occasionally (5 %) and was therefore not subjected to statistical analysis. The occurence of overgrown claws was associated with smooth slat surfaces (OR 13,7). Herds with fully slatted floors and less than 90 sows had comparably fewer problems with overgrown claws than herds with more than 139 sows (OR 3,1). In farms with fully slatted floors, bursitis occured comparatively more often when weaners were rehoused at bodyweights of > 30 kg than at weights <or= 30 kg (OR 1,8). No association could be established between limb deformities and the farm-specific factors recorded.In the rearing section overgrown claws, bursitis, limb deformation and arthritis were examined. There, the frequency of herds with overgrown claws was lower (12 %) compared to the weaning unit. This was probably related to the excl
usive use of concrete floors. However, 76 % of the farms had a problem with bursitis. The herd frequency of limb deformities (29 %) was nearly the same as in the weaning section. No association could be established between overgrown claws and the specific farm factors investigated. The chance of bursitis on fully slatted floors was 5,5-times higher than on solid concrete floors with straw bedding. Limb deformities were more often a herd problem in farms with fully slatted floors than in farms with partly slatted floors (OR 1,8). This herd problem was basically influenced by the same problem occuring in the weaning piglets section. However, since no associations between limb deformities and fanning factors could
be established in the previous production phase, no concrete countermeasures can be established.Due to the nature of the study, the associations revealed in the data collected are to be regarded merely as hypotheses. The limb diseases analyzed were influenced by a large number of different factors and a large number of residual dispersed cases could not be explained by any of the factors examined. Therefore, we recommend further comparative studies on the basis of individual pig scores in selected housing types that were detected important according to our findings.