Cross-sectional study reveals high parasite burden and diversity in wild freshwater fish, highlighting potential transmission risks to local aquaculture and human consumers.
Key Points
To assess the prevalence, diversity, and intensity of internal and external fish parasites across three freshwater species and evaluate their association with host biological traits.
Conducted a cross-sectional parasitological survey during 2023–2024 sampling Oreochromis niloticus (n = 135), Clarias gariepinus (n = 87), and Labeobarbus intermedius (n = 43).
Inspected external surfaces and internal visceral organs, classifying isolated parasite specimens morphologically to the genus level using standardized pictorial taxonomic keys.
The overall parasite infestation rate was 88.30% (n = 234/265), yielding 1,748 total parasites across nematodes, trematodes, monogeneans, myxozoans, crustaceans, and leeches.
Predominant internal parasites included Clinostomum (65.16%) in O. niloticus, as well as digenean encysted metacercariae (68.97%) and Contracaecum species (50.57%) in C. gariepinus.
Mean parasite intensity and abundance were 8.59 and 7.40 in L. intermedius, 7.92 and 7.37 in C. gariepinus, and 6.79 and 5.84 in O. niloticus, respectively.