Parasites of Commercially Important Fish Species Caught for Food in Lake Ziway, Ethiopia

Fish marketability; Parasitic infestation; Parasitic prevalence; Zoonotic diseases


  • Mekonen Hailu
    Fishery and Aquatic Life Research Center, Ethiopian Institute of Agricultural Research, Ethiopia
  • Brook Lemma Natural and Computational Sciences, Addis Ababa University, Ethiopia
  • Marshet Adugna National Fish and Aquatic Life Research Center, Ethiopian Institute of Agricultural Research, Ethiopia
  • Yacob Hailu Veterinary Medicine and Agriculture, Addis Ababa University, Ethiopia
January 1, 2023


Background: In order of importance, the most commercially important fish species often caught for food in Lake Ziway are Oreochromis niloticus, Clarias gariepinus, Carassius carassius, and Cyprinus carpio. Some fish parasites have been reported in this lake, and the lake ecosystem appears to be conducive to parasite propagation, which may have an impact on fish marketability and societal health.
Objective: The purpose of this study was to look into the prevalence of major fish parasites in four of the most commercially important fish species in Lake Ziway, as well as their effects on the commercial values of host fishes and the health of fish consumers.
Materials and Methods: From May to July 2019, the study was carried out by purchasing random samples of live fish from local fishermen at Wafiko, Korokonch, and Kafteria landing sites and administering a research questionnaire to various stakeholders. Within three months, 240 specimens from the four species were examined in the Laboratory of Batu Fish and Aquatic Life Research Center.
The data were analyzed using SPSS software.
Results: About 87.5% of the fish examined were found to be infested with 64.2% (trematodes), 42.5% (nematodes), 40% (crustaceans), 17.1% (cestodes) and 1.3% (Acantocephala). The fish examined were found to be heavily infested with zoonotic Clinostomum, Contraceacum, and Capillaria species. Thus, fishers were losing some catches due to the effect of parasites. The differences in the prevalence of parasites among the studied fish species were statistically significant (P = 0.00), but it was not
statistically significant for the fish sexes (P = 0.60).
Conclusion: Lake Ziway's commercially important fish species are heavily infested with various types of external and internal parasites, which have both health and economic consequences for the people living on raw fish as food. Therefore, it is vital that awareness creation is done and sanitary measures are taken to stem the problem of human health caused because of eating raw fish and to enhance the productivity of the lake ecosystem.