Fish is considered the most important source of full nutrition due to the content of easily digestible protein, valuable vitamins and microelements. Today the concerned departments of the veterinary and medical services of the Magadan region do not have information about the parasitological situation with respect to helminthic zooanthroponoses transmitted through marine and freshwater fishes. In this regard, the issue of studying of fish diseases and effect on people’s health has a certain novelty and absolute relevance. The aim is to study the distribution of anisacidosis and diphyllobothriasis in open and closed water bodies of the region. As a result of long-term (from 1989 to 2021) helminthological studies of 14 species of fish, the representatives of the marine and freshwater fauna, nematode larvae of 3 species were identified (Anisakis simplex, Pseudoterranova decipiens, Thynnascaris adunca) and diphyllobothriidae plerocercoids of 4 species: (Diphyllobothrium luxi, Diphyllobothrium dendriticum, Diphyllobothrium ditremum, Diphyllobothrium sobolevi). The material for the research was fish caught in three regions (Ola, Severo-Evensk and Srednekansky) in the waters of the Sea of Okhotsk and in the Kolyma river basin. The average long-term infection with the causative agents of anisacidosis and diphyllobothriasis was 66.4 % and 52.6 %, respectively. Anysakis simplex (88.0 %), located mainly in the abdominal muscles, prevail among all the species of found larvae. The highest invasion was noted in salmon of the genus Onchorynchus (chum salmon, pink salmon, coho salmon) – 92.0 %. Muscle invasion in these fish species ranges from 86.5 to 100.0 %. High values of the infestation extent by diphyllobothriidae plerocercoids were noted in pond smelt and Alaska smelt (from 56.6 to 100 %), chum salmon (20.0 %), coho salmon (20.0 %) and grayling (20.7 %). Based on the data obtained, it is concluded that anisacidosis and diphyllobothriasis are widespread among fish in open and closed reservoirs of the Magadan region.

Moskalenko Ekaterina S., Postnikova Anna B., Vitomskova Ekaterina A.

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