Trichinellosis in Badgers in the Rostov Region (Southern Russia)

Introduction. Nematodes of the genus Trichinella are the causative agents of trichinellosis, which affects humans and animals and causes significant economic damage to agricultural and food industries, especially with regard to food safety. Currently, the genus Trichinella includes 10 species and 3 genotypes, which are divided into 2 clades: encapsulated and non-encapsulated. In the wildlife, a wide range of animals participate as carriers in circulation of Trichinella, and badgers are one of the main natural reservoirs for this disease. The article provides the information on detection of the first case of Trichinella larvae in a badger in the Rostov region.
Materials and Methods. The object of the study was a carcass of a badger hunted in the Sholokhov district of the Rostov region in August 2024. Detection with further study of larvae and capsules in the samples was carried out by the method of compressor trichinelloscopy. Afterwards, histological sections were made from the individual muscles, which were stained with hematoxylin and eosin according to the standard technique.
Results. Capsules of Trichinella were found in all the examined muscles of an animal. The largest number of them was found in the diaphragm and its crura. The larvae found belonged to the encapsulated ones and were located in capsules in groups or one at a time. Histological sections showed thick collagen shells of the capsules surrounded from the outside by thin membranes of connective tissue. The results of capsule morphometry showed that their size didn't differ depending on their location in the badger’s body; the shape of the capsules in all muscles was almost round.
Discussion and Conclusion. The capsule shape indices calculated based on the morphometric results are closer to the corresponding indices of T. nativa than T. spiralis, however, this does not allow us to make fully accurate conclusions about the species membership of Trichinella, since the molecular genetic studies or the use of Western blot are required for precise diagnostics. Thus, the study of Trichinella species distribution and composition remains an extremely relevant objective that requires further research both in our region and worldwide.

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