Research of Physiological and Biochemical Parameters of Golden Mullet (Liza Aurata, Risso) in the Caspian Sea

Abstract

The paper outlines the study of the physiological and biochemical parameters 
 of golden mullet (Liza aurata, Risso) in the Caspian Sea. Collecting material was carried out in the western part of the Northern and Middle Caspian in September-October 2019. The female and male species were analyzed. The histomorphological investigation of the gonads of females and males indicated the completion of spawning. The morphological picture of the gonads of golden mullet
 of both sexes corresponded to the maturity scale of this species as applied to the Caspian region. 
 In the blood there was determined the concentration of hemoglobin, total serum protein, total lipids, triglycerides, cholesterol, glucose, and inorganic phosphorus. A valid positive correlation dependence (p < 0.05) of weight and length of females (r = 0.9340) and males (r = 0.9320) was stated. 
 In females high correlations were recorded between the levels of total serum protein and cholesterol (r = 0.9071), total serum protein and hemoglobin (r = 0.9706), glucose and hemoglobin 
 (r = 0.8897) with a statistical significance level of p < 0.05. The revealed statistical dependencies of physiological and biochemical parameters of fish blood indicated their important role in the body in optimizing the total energy costs after spawning. According to the study of males, there has been found a high (r = 0.9195) significant (p < 0.05) correlation relationship between the content 
 of hemoglobin and cholesterol in the blood. The content of total lipids in muscles, gonads and liver of females and males of golden mullet were comparable. The levels of water-soluble protein in the muscles, liver, and gonads of fish of both sexes did not differ significantly. The obtained research results on the complex of physiological and biochemical parameters of golden mullet will significantly increase the volume of reliable information about the physiological status of the organism of the studied species of mullet in the modern ecological conditions of the Caspian Sea.