Hematological, biochemical and enzymological responses in an Indian major carp Labeo rohita induced by sublethal concentration of waterborne selenite exposure

Selenium (Se) pollution in aquatic ecosystem is an environmental issue throughout the world. Elevated concentrations of inorganic Se from agricultural and industrial processes may cause adverse biological effects in aquatic organisms such as fish. In the present study, Labeo rohita an Indian major carp were exposed to sublethal concentration of Se (sodium selenite) for 35 days and certain hematological, biochemical and enzymological parameters were estimated. The median lethal concentration of waterborne sodium selenite (Na2SeO3) to L. rohita was found to be 23.89 mg L−1 for 96 h. During sublethal (2.38 mg L−1) treatment, hematological and biochemical parameters such as hemoglobin (Hb) (except 14th day), hematocrit (Hct), erythrocyte (RBC) count and protein levels were found to be decreased in Se treated fish whereas leucocyte (WBC) count and glucose level increased in Se treated fish throughout the study period. The enzymatic parameters such as glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and lactate dehydrogenase (LDH) activities were found to be increased in liver of Se treated fish L. rohita. A biphasic response was observed in the value of mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC). The alterations of these parameters can be used as suitable biomarkers in monitoring of selenium in the aquatic environment and to protect aquatic life.