Pathomorphological features of myocardial changes in piglets under industrial housing conditions

In pigs, as in other farm animals, the health of cardiac muscle is the most important factor determining the general state of the organism, and therefore plays a significant role in improving the quality of the products. Due to industrialization of pig farming, structural and functional changes in cardiac muscle can occur in early ontogenesis. Despite the fairly detailed coverage of the problem of heart pathology in farm animals, the literature does not provide much data on the features of morphological changes in the myocardium identified using a complex of histochemical methods. The objective of the research is to study pathomorphological myocardial changes in piglets using histochemical methods. To achieve this objective, the material collected postmortem from piglets aged 1-2 months (n = 3), 3 months (n = 6), and 4.5-5.0 months (n = 4) was examined. Different histological methods of preparation staining were used for the morphological examination: hematoxylin and eosin, Mallory and HBFP staining. Immunohistochemical staining with antibodies to IL-6 was performed. As a result of histological studies, areas of damaged muscle tissue attributed to myocarditis were detected in the myocardium of piglets aged 1-2 months. At the same time, a positive reaction of cardiomyocytes to IL-6 was detected, which was probably associated with the protection of muscle tissue. In piglets aged 3 months, destructive processes were expressed to a greater extent and they correlated with an increase in the area of damaged cardiomyocytes. In piglets aged 4.5-5.0 months, probably due to the activation of compensatory mechanisms, inflammatory processes were expressed to a lesser extent, and in addition, foci of myogenesis were detected. The data obtained justify further studies related to a more detailed clarification of the mechanisms of destructive processes of the myocardium in pigs of different age.

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