Helminth parasites of some tropical freshwater fish from Osse River in Benin, southern Nigeria

Abstract

Investigations into helminth parasites of freshwater fish from Osse River, Benin, revealed an overall 17.1% infection rate. Of the twelve species of fish studied, Barbus sp. had the heaviest infection rate (2.2%) while Xenomystus nigrihad the least (1.0%). Parasites recovered were the tematodes Clinostomum tilapiae, Clinostomum sp, Allocreadium sppand Diplostomum tragenna; the cestodes Polyonchobothrium sp. and Proteocephalus sp; the acanthocephalan Acanthogyrus (Acanthosentis) tilapiae; and the nematodes Camallanus sp; Procamallnus laeviconchus; Spinitectus sp; Spirocamallanus sp; Serradactnitis sp; and Spironoura sp. Nematode infection had the highest prevalence of 7.7% while trematodes recorded the least of (1.9%). A seasonal pattern of infection was demonstrated with a high infection rate in the rainy season months of June to November and a low infection rate in the dry season months of December to May.


Tropical Freshwater Biology VOL. 8 1999, pp. 41-48



KEY WORDS:

helminth parasites – prevalence - freshwater fish - seasonal effects.