Dolops ranarum from Oreochromis esculentus and Protopterus aethiopicus in Lake Kanyaboli, Kenya: Additional Information Using Scanning Electron Microscopy

Olonde, Felix; Rindoria, Gladys; Morara, George; Smit, Willem; Powell, Wilmien; Rindoria, Nehemiah

doi:10.21608/ejabf.2025.418365

Dolops ranarum from Oreochromis esculentus and Protopterus aethiopicus in Lake Kanyaboli, Kenya: Additional Information Using Scanning Electron Microscopy

Authors

10.21608/ejabf.2025.418365

Abstract

Fish parasites are often overlooked, yet they can have detrimental effects on both capture fisheries and aquaculture, leading to significant economic loss. Heavy infestation of external parasites on the fins, skin and gills of fish may lead to pathogenic effects or may create a suitable environment conducive to secondary infections. This study, conducted in Lake Kanyaboli from January to March 2024, aimed to identify the ectoparasites of the endemic species Oreochromis esculentus and Protopterus aethiopicus, and asses their infection levels and diversity. A total of 60 specimens of each host species were examined for the presence of ectoparasitic crustaceans. The parasites collected were subjected to morphological examination using scanning electron microscopy (SEM). The infection (prevalence and mean intensity) and diversity (Margalef richness, Shannon-Wiener and Simpson’s) levels were calculated. Morphological analysis identified the branchiuran (Dolops ranarum). A prevalence rate of 76.7% was recorded for D. ranarum from O. esculentus and 90% from P. aethiopicus with a mean intensity of 1.39 and 1.59, respectively. The parasite diversity indices of D. ranarum were relatively diverse in P. aethiopicus, but dominant in O. esculentus. SEM observations revealed additional taxonomic features which have not been previously described. In addition, the study provided an updated taxonomic key to Dolops species and extended the geographical locality of D. ranarum to Kenya.

Keywords