Effects of Acclimation Temperature and Feeding Rate on Carbohydrate-Metabolizing Enzyme Activity and Lipid Content of Common Carp.

Abstract

Common carp Cyprinus curpio were fed for 40 days with a diet at different temperatures and feeding rates, and the activities of several carbohydrate-metabolizing enzymes and the body com position were determined at the end of the experiment. In both cold (17°C)- and warm (27°C)- acclimated fish, activities of hepatopancreatic glucosephosphate isomerase, glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, and glutamic pyruvic transaminase as well as the body lipid content increased with an increase in feeding rate, though glucose-6-phosphatase activity was nearly constant regardless of feed intake. When the fish were fed at the same feeding rates, the activities of all the enzymes tested together with apparent lipid retention were higher in the cold-acclimated fish than in the warm-acclimated fish, suggesting a metabolic compensation for cold temperature by the regulation of enzyme activity in the poikilothermic animal. The results indicate that the acclimation temperature and feeding rate separately or cooperatively affect the carbohydrate-metabolizing enzyme activities and lipid contents in the fish. © 1993, The Japanese Society of Fisheries Science. All rights reserved.