PubMed1989
The economic loss resulting from the skinning and trimming of pig carcases is estimated at from 2.5 to 3 million Netherlands guilders per annum. In addition, this dermatitis also gives rise to logistic problems. The pilot project 'Integrated Quality Control' (IQC) is concerned, among other things, with studies designed to result in an optimum method of inspection. For this purpose, the meat inspectors recorded a number of pathological findings on ante-mortem inspection, including 'dermatitis'. Living animals did not show any clinical symptoms, and the dermatitis recorded by the meat inspectors was non-specific. There was believed to be a relationship between scabies (Sarcoptes scabiei var. suis infection) on the farm and the prevalence of dermatitis on the carcases of pigs. To determine whether this dermatitis was due to scabies, pathological and histological investigations were carried out in twenty animals. The recordings of the meat inspector were also analysed. Histopathological findings suggested parasitic infection, also in view of the fact that sarcoptic infection is known to coincide with allergic reactions. Dermatitis was detected in 5,712 out of 722,273 carcases (0.79 per cent) examined in a single plant in 1987; 1,855 cases (1.27 per cent) occurring in the winter, 1,798 cases (0.96 per cent) in the spring, 1,357 cases (0.65 per cent) in the summer and 710 cases (0.39 per cent) in the autumn. With the exception of the winter and spring, the consecutive seasons differed significantly (p less than 0.01). 136,434 animals of sixty-nine pig farms which took part in the IQC programme, were examined in 1987. The prevalence of carcases showing dermatitis on these farms varied from 0 to 6.3 per cent, averaging 0.66 per cent. The pathological findings in these investigations suggest a causal relationship between scabies and 'dermatitis' as recorded by the meat inspector.