A comparative study of helminth parasites from the fishTilapia zilliiandOreochromis leucostictusin Lake Naivasha and Oloidien Bay, Kenya

Abstract

AbstractThe parasitic fauna of two fish species, namely gill-netted samples of 652Oreochromis leucostictusand 448Tilapia zilliifrom Lake Naivasha and Oloidien Bay was investigated during the period from the end of October 1995 to September 1996. Five larval helminth parasites were recovered including the nematode,Contracaecumsp., the acanthocephalanPolyacanthorhynchus kenyensis, the digenetic trematode,Clinostomumsp. and two cestodes,Amirthalingamiasp. andCyclusterasp. Both prevalence and intensity of the infection of these helminths increased in larger sized fish, whereas male fish were more heavily infected than females. No seasonality in infection level were observed. The health status of both fish species remained unaffected, althoughO. leucostictusfrom Oloidien Bay which harboured heavy infections ofContracaecumexhibited stuntedness and the lack of fatty deposits around the digestive caecum.