Occurrence and risk factors associated with Eimeria species infections in Clarias gariepinus and Heteroclarias species

Eimeria infection can cause a serious health risk to fish in the wild and especially to the fish production enterprise. Eimeria species are a group of protozoan parasites common in many fish farming systems with little information available on the occurrence, impact, and risks associated with the infection in fish populations. This study was conducted to ascertain the prevalence and risk factors associated with Eimeria species infections in three hundred and seventy-six Clarias gariepinus and Heteroclarias species from some selected fish farms in Kaduna state, Nigeria. Using direct smear techniques, oocysts were recovered from the mucous and intestinal content of the fish. Data on the risk factors were obtained by administering a well-structured questionnaire to the fish farmers. An overall prevalence of 30.3 % was obtained for the apicomplexan parasite of the genus Eimeria. The monthly prevalence of Eimeria species infection among fish was highest in October and the lowest in July. Some risk factors were significantly (p <0.05) associated with fishes in the univariate model. Sex of fish, level of formal education of farmers, feeding of fish with dead poultry and fish, and the number of ponds in a fish farm were the significant risk factors in the multivariate model. This finding indicates that Eimeria species infection is endemic and of great concern among the fish population, thereby posing significant health problems. There is a need for improved fish management practices and biosecurity protocols.