Comparative Parasitic Infections in Gymnarchus niloticus (Cuvier, 1829) and Heterotis niloticus (Cuvier, 1829) in Lekki Lagoon, Lagos State, Nigeria

Bamidele, Akinsanya; Awolumate, Samuel; Taiwo, Adubi; Ovioma, Godwin; Excellence, Akeredolu; Otubanjo, Zainab; Oyinkansola, Tobi; Nwanma, Henrietta I.; Nyerede, Odiogbeyi; Ishola, Akpome; Eloho, Patience; Omoregie, Isibor P.; Evelyn, Olotuah O.

doi:10.21608/eajbsz.2025.430013

Comparative Parasitic Infections in Gymnarchus niloticus (Cuvier, 1829) and Heterotis niloticus (Cuvier, 1829) in Lekki Lagoon, Lagos State, Nigeria

Document Type : Original Article

Authors

¹ Department of Zoology, University of Lagos, Akoka, Nigeria.

² Department of Animal Science and Fisheries, National Open University of Nigeria.

³ Department of Biological Sciences, Yaba College of Technology, Yaba, Lagos,Nigeria.

⁴ Department of Biological Sciences, College of Sciences and Technology, Covenant University, Ota, Ogun state, Nigeria.

10.21608/eajbsz.2025.430013

Abstract

This study investigates the comparative parasitic infections in Gymnarchus niloticus (Cuvier, 1829) and Heterotis niloticus (Cuvier, 1829) within the ecological context of Lekki Lagoon, Lagos State, Nigeria. Both species, integral to the biodiversity and fisheries of the lagoon, exhibit ecological differences influencing their parasitic burdens. A total of 200 specimens (100 per species) were collected and examined for ecto- and endoparasites using standard parasitological techniques. Results revealed a higher prevalence and mean intensity of parasitic infections in Heterotis niloticus (Tenuisentis niloticus) (65%) compared to Gymnarchus niloticus ( Raphidascaroides sp)(48%), with significant variation (p < 0.05) in parasitic taxa between the two hosts. Identified parasites included helminths (nematodes and trematodes), protozoans, and monogeneans, with Heterotis niloticus hosting a more diverse assemblage, likely attributable to its bentho-pelagic feeding strategy and omnivorous diet, which increase exposure to intermediate hosts. Conversely, Gymnarchus niloticus, as a piscivorous species, exhibited fewer parasite species, dominated by trophically transmitted helminths. Seasonal variations significantly influenced infection rates, with peaks during the wet season correlating with increased host density and ecological interactions. The findings underscore the ecological drivers of parasitism in Lekki Lagoon and their implications for fisheries management. Understanding host-parasite dynamics in these commercially and ecologically significant species is crucial for sustainable exploitation and conservation strategies in freshwater ecosystems.

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