Diagnosis and Management of Coccidiosis in a Clarias gariepinus Catfish Farm: A Case Report

Coccidia are spore-forming obligate intracellular protozoan parasites that cause disease in several animal species, including fishes. In this report, we present the clinical diagnosis and therapeutic management of a case of coccidiosis in a Clarias gariepinus catfish farm with a high morbidity and mortality rate. Following the report of an increasing mortality on the farm, fish showing nondescript signs were sampled, and subjected to parasitological evaluation. Dissection of the small intestines revealed small white to grayish raised nodules in portions of the anterior intestines, the mucosa of the small intestine also showed congestion, hemorrhage, and presence of brownish blood-mixed contents in the intestinal lumen. Histological examination of sections of the small intestines showed the presence of cystic structures full of spores (sporocyst of about 580 μm in size) developed in portions of the anterior intestine of the affected fishes. These were identified as Coccidian sp. because of their similar morphology to those of the parasites in the Coccidian group. Based on history, clinical symptoms, gross, feacal and histopathological findings, the present case was diagnosed as coccidiosis. Treatment was instituted with amprolium delivered through ‘top-dressing’ of the feed at 0.05% for 5 days. Effectiveness of the instituted treatment could not be ascertained, as the owner sold of the entire flock to cut further losses on the farm.