Parasite community of wild and cultured Oreochromis niloticus from Lake Manzalah, Egypt

A total of 323 O. niloticus (168 wild fishes and 155 cultured fishes) were collected from Lake Manzala, Egypt from July to September 2010. The fish samples were examined for both ectoparasites and endoparasites. The parasite community of wild and cultured, O. niloticus consisted of ten parasitic species, one protozoon (Trichodina spp.), six monogenea (Cichlidogyrus sclerosus, C. thurstonae, C. halli typicus, C. tilapiae, C. ergensi, C. tiberianus), one acanthocephalan (Acanthogyrus (Acanthosentis) tilapiae) and two crustacean species (Lernaea cyprinacea and Ergasilus sp.). Mean parasite species richness significantly differed between wild (4.9 +/- 0.3) and cultured (6.6 +/- 0.8). The overall prevalence of infection in cultured O. niloticus (54.84%) was significantly higher as compared to that in wild fish (39.9%). The most prevalent parasite was C. thurstonae (37.46%) and C. sclerosus (35.91%) while the less prevalent one was Ergasilus sp. (14.55%). Host sex and host body size significantly affect parasitism in most parasite species.