抽象的な

Survey of the Cymothoid Parasites Associated with some Estuarine Fishes (Actinopterygii) from the Upper Reaches of the Bonny Estuary Nigeria: Their use in Ecotoxicological Studies

Ugbomeh AP*, Nwosu OR

Five hundred and forty two (542) fishes belonging to 9 species (Pomadasys peroteti, Tilapia spp, Arius gigas, Elops lacerta, Eucinostomus (Gerres) melanopterus, Pseudotolithus elongatus, Liza grandisquamis and L. falcipinnis) were collected from 5 landing sites along the upper reaches of the Bonny river in Nigeria and examined for macro-ectoparasites. Parasites isolated were Cymothoa exigua, C. hermani, Nerocila monodi, an unidentified Nerocila spp and Lironeca vulgaris. Total prevalence for all parasites was 37%. For each parasite, the host fish, parasitic specificity and prevalence are given. P. peroteti and Tilapia spp had the highest parasite prevalence. The Cymothoa species were found in the mouth replacing the tongue, in the pharynx attached to the gill arch and externally on the skin of P. peroteti and Tilapia, Lironeca vulgaris was found in the mouth while the Nerocila species were found on the skin. A toxicological survey of the concentration of heavy metals (Cd and Pb) in fish and parasite showed the absence of heavy metals in all parasites while the fish had concentrations above recommended permissible limits. There was no significant difference in the prevalence among stations.