Morphological and histochemical changes in pig liver under the influence of mycotoxins and antiparasitic treatment with eprinomectin against the background of subclinical mycotoxicosis

The liver, as a multifunctional organ, participates in the regulation of homeostasis and plays an important role in maintaining the health and productivity of animals. The action of numerous stress factors on animals in the conditions of industrial livestock farming induces the development of morphofunctional changes in liver. In this regard, the goal was set to establish morphological and histochemical changes in the liver of pigs with multiple contamination of feed with mycotoxins and carrying out antiparasitic treatment against this background. The experiment was performed on three groups of pigs. The first group is the control group. Animals of the 2nd and 3rd experimental groups received food containing mycotoxins (deoxynivalenol - 0.93 mg/kg; T-2 toxin - 0.025 mg/kg; zearalenone - less than 0.02 mg/kg). At the same time, animals of the 3rd group underwent antiparasitic treatment with Veteprin (the active substance is eprinomectin) at a dose of 300 mcg/kg once. The duration of the experiment was 45 days. Histological examination of the liver of control animals showed no signs of pathological changes. Vascular changes and disruption of the parenchyma beam structure were recorded in the liver of animals of the second group. In the central part of the lobules there were hepatocytes with signs of atrophy and dystrophy: their borders were smoothed, the nuclei were in a state of pyknosis. Hepatocytes were slightly enlarged in size, and their cytoplasm contained acidophilic granular mass. In some cases, partial cytolysis was observed with the formation of vacuoles in the cytoplasm. At the same time, the content of nucleic acids and glycogen in the liver was reduced, small droplet inclusions of lipids were present in hepatocytes, and lobular variations in the protein content in cells were noted. Thickening of the walls of interlobular and intralobular vessels, more pronounced deformation of the hepatic cords, and the presence of micronecrosis sites were recorded in animals of the 3rd group. Histochemical examination revealed a decrease in the RNA content in the cytoplasm of hepatocytes, a sharp decrease in glycogen content, and a significant amount of fat droplets. Most of the injuries (dystrophic processes, vascular disorders, disturbance in cellular metabolism) are reversible and can be considered as a manifestation of adaptive reactions.