HAEMATOLOGICAL CHANGES IN Oreochromis niloticus (OSTEICHTHYES: CICHLIDAE) WITH GILL ICHTHYOPHTHIRIASIS AND SAPROLEGNIOSIS

Abstract

The effects of gill ichthyophthiriasis and saprolegniosis in haematological parameters and relative condition factor (Kn) of Oreochromis niloticus (Nile tilapia), naturally infected with Ichthyophthirius multifiliis and Saprolegnia sp. were studied, in comparison with those of healthy fish. Results show no difference in relative condition factor between the two groups. However, red blood cells count (RBCC), lymphocytes percentage, hemoglobin concentration, hematocrit and mean corpuscular hemoglobin concentration were significantly lower when compared with the healthy group (P<0.01). In addition, mean corpuscular volume, neutrophils and monocytes percentage were significantly higher (P<0.01) in the infected fish. Thrombocytes showed no differences (P>0.05). No relation between the thrombocytes and the mechanism of organic defense was observed. These results suggest that the parasitism induced anemia and increase in the percentage of circulating neutrophils and monocytes.