Pathological Changes in the Microstructure of Pale, Soft, Exudative (PSE) and Normal Turkey Breast Muscle

The aim of the study was to determine the type and extent of histopathological changes in PSE and normal breast muscle of turkey. Changes in fibre size (atrophy, hypertrophy - giant fibres), changes in fibre shape (angular fibres), degenerative lesions (necrosis with phagocytosis) and connective tissue hypertrophy were evaluated. The present study showed that significantly fewer normal fibres were found in the muscles of PSE group compared to the normal group. Moreover, the histopathological changes observed in all birds from the PSE and normal groups included muscle fibre atrophy and change in fibre shape (angular fibres), with both the percentage of female turkeys showing this type of pathology and the frequency of atrophic and angular fibres being significantly higher in birds from the PSE group. Also in the case of giant fibres, the muscles of PSE group were characterized by a greater number of animals with giant fibres and a significantly higher proportion of giant fibres compared to normal group. In the case of connective tissue hypertrophy and necrosis with phagocytosis, the changes observed in this study were not extensive in either groups of birds. In summary, the PSE syndrome contributes to a significant increase in the frequency of histopathological changes in muscle tissue, and this may directly translate into meat quality.