Hematological Changes Associated with Epizootic Ulcerative Syndrome in the Asian Cichlid Fish, Etroplus suratensis

Abstract

Apparently healthy and epizootic ulcerative syndrome (EUS)-positive Etroplus suratensis collected from Hamilton Canal, Negombo, Sri Lanka, were subjected to a hematological examination. The hematological parameters studied were total erythrocyte count, total leucocyte count, hematocrit, hemoglobin content, mean erythrocyte volume, mean erythrocyte hemoglobin content, mean erythrocyte hemoglobin concentration and differential leucocyte count. Results indicate that severely affected fish were anemic as shown by significant reductions in total erythrocyte count, hematocrit and hemoglobin content. In addition, the differential leucocyte counts of severely affected fish indicate a significant increase in the percentage of neutrophils. The anemic condition can be attributed to the hemorrhagic lesions that resulted in blood loss in the severely affected fish. Increase in neutrophils may be a result of local inflammation and tissue damage due to severe EUS lesions.