Abstract: From September, 1998 to August, 1999, the Heamotological indices of Southern catfish( Silurus meridionalis ) are investigated. The result shows that the erythrocyte count and hemoglobin content value of Silurus me ridionalis are higher than those of Ari stichthys nobilis, Carassius auratus, Megalobrama amblycephala and Carassius auratus cuvieri , which indicates the consistency with its eating flesh habit and the features of fast growth and less disease. The differential leukocyte count is a new type, i. e. , the kind that is composed mainly by lymphocytes, and has few neutrophilic granulocytes and monocytes and many thrombocytes. The erythrocyte count , the percentage of lymphocytes,the percentage of thrombocytes and the size of all the kinds of blood cells have significant year-round changes.

Key words: Silurus meridionalis, heamotological indices, year-round changes