The cultivation of sharptooth catfish (Clarias gariepinus burchell) when the use of compound feed with different protein level

Abstract

It has been found as a result of the research that sharptooth catfishes grown on a highprotein diet (the 2nd variant) had a higher growth rate compared to fish that consumed low-protein, but cheap feed (the 1st variant). The average daily gains of fish in the 2nd variant of the experiment corresponded to 6,1 g/day, which was 3,4 g higher compared to the herdmates of the 1st variant. During the experiment period (60 days) the individual weight of catfishes that consumed low-protein compound feed has been increased by 160 g while fish have been grown on high-protein compound feed added 364 g, which was 2,3 times more. In the end the higher yield of fish products per unit of water area has been obtained in the 2nd variant of the experiment 271,2 kg/m[sup]3[/sup] against 118,4 kg/m[sup]3[/sup] in the 1st variant. However, economic analysis has shown that the use of expensive high-protein feed does not give a significant effect. The additional profit in the 1st variant was only 12 %. Catfishes have been grown on high-protein compound feed had the best conformation and technological indicators. They differed from their herdmates from the other variant with higher indicators of edible body parts their body contained less internal fat. High growth and better physiological condition of catfishes that consumed higher-quality protein feed are confirmed by interior, hematological and biochemical indicators. Their blood had a higher concentration of protein, hemoglobin, and fewer white blood cells. In catfishes of the 1st variant the higher level of AST and ALT enzymes has been found in the blood serum, which indicates a low protein metabolism, increased urea synthesis and the high load of work of the liver.