Morphological and functional characteristics of Trichinella sp. larvae in bears and badgers in the Kirov Region

The purpose of the research is study of morphological and functional characteristics of Trichinella sp. larvae in bears and badgers in the Kirov Region.
Materials and methods. The compressor trichinelloscopy (CT) method was used to study 72 sections of muscle tissue samples (in accordance with the Guidelines "Prevention of helminthiasis transmitted through meat and meat products" dated September 23, 1996) from animals obtained during scientific culling. The sections were prepared from the diaphragmatic peduncle muscles and the diaphragm of bears and badgers along the muscle fibers, and placed in the compressorium. The sections were then transferred to glass slides, and provisional slides were prepared and examined using various magnifications (× 8, × 20, × 40). Morphometric measurements were performed using a microscope at × 40 magnification, then the capsule index was calculated. Digestion (peptolysis) in artificial gastric juice was performed according to the P. A. Vladimirova’s method modified by A. V. Uspensky and F. Skvortsova after the test samples were placed in various temperature conditions from 5 to -18 °C, and the parameters of both animal species were compared. The viability of Trichinella sp. larvae was evaluated in a Petri dish in saline at a room temperature. Morphological changes were recorded in the larvae structure (coiled larvae against the total number of isolated, coiled and stretched larvae) and their mobility.
Results and discussion. We studied badgers and bears infected by Trichinella spiralis larvae in the Kirov Region. The Trichinella sp. larvae were found in all examined sections of the infected animals. The infection intensity was higher in the badger than the bear and amounted to 218±79.5 larvae per 1 g of muscle, while it was 115±28.5 in the bear. The stated above is explained by the fact that the badger eats carrion more often, and typically visits spontaneous dumps. For postmortem diagnosis of trichinellosis in the obtained bears and badgers, we can use trichinelloscopy and peptolysis methods which are aimed at detecting infection sources and preventing zoonosis in humans.

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