ABSTRACT
Selenium (Se) is described as an essential micronutrient and participates in different biological functions, as the antioxidant defense systems maintenance and regulation. However, when in high concentrations, Se may cause toxic effects as well as hematological changes in fish. The aim of the present study was to determine the toxicity of selenium in the form of sodium selenate (Na2Se6+O4) in Oreochromis niloticus based on hematological parameters, after exposure to different concentrations (0.01, 0.14 and 1.4 mg Se6+ L-1). The erythrocytic and leukocytic series were examined over 14 days at intervals of 0, 3, 5, 7,10 and 14 days. The erythrocytic series showed significant alterations in the first 7 days, including the control group. Neutrophils and monocytes showed variations in the first 3 days at a concentration of 1.40 mgSe6+ L-1 characterizing an acute response. The total number of leukocytes was different in relation to time zero on all Se concentrations. The thrombocyte count also differed statistically from time zero and control in the first 3 days at 0.14 mgSe6+ L-1. These results indicate that different concentrations induce an acute response with diminution of total leukocytes, neutrophilia, monocytosis and thrombocytosis.
ABSTRACT
Selenium (Se) is described as an essential micronutrient and participates in different biological functions, as the antioxidant defense systems maintenance and regulation. However, when in high concentrations, Se may cause toxic effects as well as hematological changes in fish. The aim of the present study was to determine the toxicity of selenium in the form of sodium selenate (Na2Se6+O4) in Oreochromis niloticus based on hematological parameters, after exposure to different concentrations (0.01, 0. 14 and 1.4 mg Se 6+ L-1). The erythrocytic and leukocytic series were examined over 14 days at intervals of 0, 3, 5, 7,10 and 14 days. The erythrocytic series showed significant alterations in the first 7 days, including the control group. Neutrophils and monocytes showed variations in the first 3 days at a concentration of 1.40 mgSe6+ L-1 characterizing an acute response. The total number of leukocytes was different in relation to time zero on all Se concentrations. The thrombocyte count also differed statistically from time zero and control in the first 3 days at 0.14 mgSe6+ L-1. These results indicate that different concentrations induce an acute response with diminution of total leukocytes, neutrophilia, monocytosis and thrombocytosis.
O selênio (Se) é descrito como um micronutriente essencial e participa de diversas funções biológicas. No entanto, quando em concentrações elevadas, o Se pode causar efeitos tóxicos, bem como alterações hematológicas em peixes. O objetivo do presente estudo foi determinar a toxicidade do selênio na forma de Selenato de sódio (Na2Se6+ O4) em Oreochromis niloticus com base em parâmetros hematológicos, após a exposição a diferentes concentrações (0,01, 0,14 e 1,4 mg + Se6+ L-1). A série eritrocitária e leucocitária foram examinadas por 14 dias, em intervalos de 0, 3, 5, 7,10 e 14 dias. A série eritrocítica mostrou alterações significativas nos primeiros 7 dias, incluindo o grupo controle. Neutrófilos e monócitos apresentaram variações nos primeiros 3 dias na concentração de 1,40 mgSe6+ L-1, caracterizando uma resposta aguda. O número total de leucócitos foi diferente em relação ao tempo zero em todas as concentrações de Se. A contagem de trombócitos também diferiram estatisticamente entre o tempo zero e os primeiros 3 dias a 0,14 mgSe6+ L-1. O resultados indicam que diferentes concentrações induzem a resposta aguda com diminuição dos leucócitos totais, neutrofilia, monocitose e trombocitose.