An Investigation of Larval Ascaridoid Nematodes in Some Marine Fish from the Gulf of Thailand

Abstract

Larval Ascaridoid nematodes were investigated from in 1,880 samples from 78 species of marine fish from the Gulf of Thailand. Four genera of larval Ascaridoid nematodes: Anisakis, Contracaecum, Porrocaecum and Rhaphidascaris were found in the mesenteries, visceral organs and the intestines of 57 samples of 11 marine fish species. Larvae of the genus Anisakis were found in four species of fish (Muraenesox sp., Epinephelus areolatus, Rachycentron canadum, Trichiurus lepterus). Larvae of the genus Contracaecum were found in two species of fish (Priacanthus tayenus, Scolopsis dubiosus). Larvae of the genus Porrocaecum were found in two species of fish (Priacanthus tayenus, Seriolina nigrofasciata). Larvae of the genus Rhaphidascaris were found in four species of fish (Dasyatis sp., Plotosus anguillaris, Johnius dussumieri, Pelates quadrilineatus). Priacanthus tayenus was infected with the highest number of species of Ascaridoid nematodes (2 genera). The highest number of Ascaridoid nematodes per fish was observed in Muraenesox sp., which was infested with 3.75 Anisakis per fish. In this study, Anisakis followed by Rhaphidascaris, were found in 63 (52.07%) and 32 (26.45%) fish samples, respectively.