Endo-helminths Infestation in Nile Perch, Lates niloticus, (L.,) and Nile Tilapia, Oreochromis niloticus (L.,) in Winam Gulf of Lake Victoria, Kenya

Abstract

Nile tilapia, Oreochromis niloticus (L., 1758) and Nile perch, Lates niloticus (L., 1758) were introduced into Lake Victoria in 1950, mainly to boost the fishing economy. Parasitic infections remain a major concern to the fish industry. It has recently been identified as an important public health problem with considerable economic impact. Data on parasitic infections on the two fish species is scarce; particularly in the Winam Gulf of Lake Victoria. Therefore, this study aimed at investigating the prevalence, mean intensity and mean abundance of endo-helminths infecting O. niloticus and L. niloticus in the Gulf. A total of 320 fish comprising 151 O. niloticus and 169 L. niloticus were caught weekly and transported alive to Egerton University. Prior to examination, fish were killed humanely by cervical dislocation. The total length were taken using a calibrated dissecting board and weights were obtained using a sensitive weighing balance (Sartorius ED4202S). Fish were dissected immediately and subjected to parasitological examination using standard procedures. Eleven parasite taxa were recovered from O. niloticus, with Tylodelphys sp. dominating the community. On the other hand, six parasite taxa were recordedfrom L. niloticus, with Armithalingamia macracantha dominating (P =5.3% MI = 4.6 and MA = 0.2). We conclude that L. niloticus had a poor parasite fauna, while O. niloticus had a rich parasite fauna. Despite the low infection level of Bothriocephalus acheilognathi and Heterophyes sp., are still the major parasites of concern, especially considering their potential zoonotic effect.