Hematological and histological parameters of Nile tilapia in response to the challenge of different salinity levels

Abstract

This research aimed to evaluate the influence of different levels of salinity on growth performance, haematological parameters and the cells of Nile tilapia chloride. 144 fish were used during a 97 day trial period, submitted to four experimental treatments of 0 ‰, 10 ‰, 20 ‰ and 25 ‰ salinity. Sampling were collected for monitoring of performance parameters, blood samples to determine the erythrocyte count, packed cell volume, hemoglobin concentration, the erythrocyte indices, the count of thrombocytes and leukocytes and the electrophoretic profile of serum proteins. Gill samples were also collected for counting the number of cells chloride. Significant differences were found in hemoglobin concentration, the total plasma proteins and the number of erythrocytes (p <0.05). There was no difference in the number of white blood cells and thrombocytes. Serum proteins showed differences (p <0.05) from pre-albunima fractions, α1-globulin, α2-globulin, βglobulin, and γ-globulin. There was a direct relationship between the number of chloride cells and increase in salinity levels (p <0.05). The CBC constituents, the electrophoretic profile of proteins as well as quantitative analysis of gill chloride cells can serve as indicares mechanism of adaptation and tolerance to salinity in Nile tilapia.