Clinical manifestations and patterns of progression of cryptocaryonosis in marine fish under aquarium conditions
Stepankov A.P. 1
Year: 2026, Number: 2, Pages: 82-90
This study presents observations of a parasitic disease caused by Cryptocaryon irritans Brown, 1951 in marine fish maintained in closed aquarium systems. Based on clinical assessment and microscopic examination, two forms of the disease were identified, a typical (cutaneous) form and a gill-associated form, differing in parasite localization, clinical manifestation, and disease progression. The typical form was characterized by prolonged persistence and relatively low mortality, whereas the gill-associated form involved parasite localization within the epithelium of the gill lamellae, impaired respiratory function, and caused rapid mortality. Analysis of published data indicates that cases with predominant gill involvement have been reported, but are rarely considered as a distinct clinical form. The findings highlight the importance of including gill examination in diagnostic protocols, particularly in public aquarium systems.
DOI: 10.25221/2782-1978_2026_2_8
Keywords: parasitic disease, Cryptocaryon irritans, marine fish, gill-associated infection, clinical manifestations, diagnostics, Primorsky Aquarium,
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