ABSTRACT
Parasites are part of the aquatic community, and freshwater fishes are known to serve as definitive, intermediate or paratenic (transport) host in the life cycle of many species of parasites. They are afflicted by endo and ectoparasites, especially protozoans and helminths causing heavy mortality. There is an appreciable documentation of parasitic fauna of Clarias gariepinus in Nigeria but Owan River is one of those in which information on parasite of fish species is limited. This study was aimed at investigating the helminth parasites of Clarias gariepinus in Owan River, Edo State.
Samples of C. gariepinus were collected between February and September 2017, using fishing traps, cast and gill nets of various mesh sizes. Routine measurement of standard length, total length and body weight were taken. The gastro-intestinal tract and abdominal cavity were carefully examined for parasites in different Petri dishes containing 0.75% normal (physiological) saline.
Results showed that six species of helminth parasites belonging to two taxonomic phyla; Platyheminthes and nematoda, were recorded. Parasites recovered were Allocreadium sp., Proteocephalid sp., Lytocestus sp., Procamallanus laeviconchus, Camallanus sp. and Psuedonisakis rotundata.The prevalence of Nematode infection was highest (61.3%), followed by cesteodes (27.7%) and trematodes (10.9%). Percentage prevalence of parasite species was Allocreadium sp. (10.9%), Proteocephalid sp. (15.9%), Lytocestus sp. (11.8%), Procamallanus laeviconchus (19.3%), Camallanus sp. (24.4%) and Psuedonisakis rotundata (17.6%). In relation to location of parasite in host; Camallanus sp. (10.35%) was highest in the stomach while Pseudonisakis rotundata (7.59%) was the least and for the intestine Proteocephalid sp. (4.79%) was the highest and Allocreadium sp. (4.64%) the least. Parasite prevalence was higher in males (25.00%) than females (17.11%) fishes, while parasite prevalence was highest in the fishes with weight range of 19.19 – 123.23g and 15.52 – 65.10g in March and August (17.65%). The need to create awareness on the need and necessities for studies on the parasitic infections of fish, as regards the optimum growth of fisheries and health consciousness is important.
