Comparative Studies of Hepatic and Blood Biomarkers in Three Species of Black Sea Elasmobranchs

Abstract

The investigations of elasmobranchs are very important for the understanding of evolutionary process and mechanisms of fish adaptation. Fishing pressure and global climate changes are affecting elasmobranch population size and structure. Baseline data of these taxa from different locations are useful for the evaluation of their health and for development of the methods of their preservation. In this study Aminotransferases (ALT and AST) activity, oligopeptides, albumin and hemoglobin concentrations were determined in the liver, red blood cells and blood serum of three Black Seaelasmobranch species: Atlantic spiny dogfish Squalus acanthias, buckler skate Raja clavata and stringray Dasyatis pastinaca. Interspecies differences of enzymatic activities depending on fish biology and ecology were shown. Hepatic aminotransferases level and serum oligopeptides concentration were greater in benthic/pelagic active shark, than in benthic sluggish rays. Oligopeptides concentration in red blood cells was the similar in tested elasmobranchs, while serum enzymatic activity and hepatic oligopetides level were higher in R. clavata than in D. pastinaca and S. acanthias inhabiting deeper waters. The results demonstrate that the complex of biochemical characteristics of elasmobranchs together with their ecological specificity can be used to indicate the main strategy of biochemical adaptation of fish evolutionary process.