Altogether 180 specimens of Perca fluviatilis (L.) from Srebarna Lake, North-eastern Bulgaria, were examined for helminths during spring, summer and autumn of 2005 – 2006. Of them, 143 (79.4 %) perch were infected with helminths. Thirteen helminth species were found: metacercariae of Bolbophorus confusus, Diplostomum pseudospathaceum, D. spathaceum, Ichthyocotylurus pileatus, Posthodiplostomum cuticola and Tylodelphys clavata; cestode Proteocephalus percae; acantocephalans Acanthocephalus anguillae and A. lucii and nematode larvae Contracaecum microcephalum, Eustrongilides excisus, E. tubifex and Rhaphidascaris acus. The digenean T. clavata was dominant species of the perch component community. Little seasonal differences were found in the prevalence, abundance and mean infection of helminths. Eustrongilides tubifex reported from the territory of Bulgaria for the first time, represent the new geographical records and new species of Bulgarian helminth fauna.
P. fluviatilis was reported as a new host record for two digeneans, namely Diplostomum pseuspathaceum and Posthodiplostomum cuticola, the cestode Proteocephalus percae, the acantocephalan Acantocephalus anguillae and the nematodes Contracaecum microcephalum and E. tubifex from the territory of Bulgaria. P. fluviatilis was reported as a new host record for D. pseudospathaceum, P. cuticola, C. microcephalum and E. tubifex from Balkan peninsula.
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