![]() |
|
|
Department of Biochemistry, Mississippi State University, Mississippi State, MS 39762
Three isonitrogenous, isoenergetic diets were formulated with varying levels of carbohydrate (CHO) and lipid to determine the effect of energy source on lipogenic enzyme activities in fingerling channel catfish. Diets A, B, and C contained, expressed as a percentage of total energy, 0% CHO and 49% lipid, 16% CHO and 33% lipid, and 46% CHO and 3% lipid, respectively. Duplicate groups of 60 fish weighing 435 ± 5 g/group were fed 3% of their wet weight per day. Fish fed the high lipid (A) diet grew as well as fish fed the high-CHO (C) diet. Fish fed diet B, however, had a significantly greater growth rate. Fish were sampled and composite samples of liver and mesenteric adipose tissue were assayed for the following enzymes: fatty acid synthetase, malic enzyme, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and NADP-isocitrate dehydrogenase. In both hepatic and adipose tissue, all lipogenic enzymes assayed were stimulated by the high-CHO diet. All lipogenic enzymes were depressed by the high lipid diet only in hepatic tissue. Enzyme activities were much lower in adipose tissue relative to hepatic tissue. The marked stimulation of the hepatic lipogenic enzyme activities by dietary CHO may explain why catfish can utilize higher levels of dietary CHO than certain solmonid fishes.
KEY WORDS: lipogenic enzymes channel catfish
1 Mississippi Agricultural and Forestry Experiment Station publication 4912.
2 Based on a thesis submitted by the senior author to the graduate faculty of Mississippi State University in partial fulfillment of the requirements for the degree of Master of Science in Biochemistry.
3 A preliminary report on this work was presented at the 65th Annual Meeting of the Federation of American Societies For Experimental Biology, Atlanta, GA, April, 1981.
Manuscript received 28 July 1981.
This article has been cited by other articles:
![]() |
C. Kolditz, M. Borthaire, N. Richard, G. Corraze, S. Panserat, C. Vachot, F. Lefevre, and F. Medale Liver and muscle metabolic changes induced by dietary energy content and genetic selection in rainbow trout (Oncorhynchus mykiss) Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2008; 294(4): R1154 - R1164. [Abstract] [Full Text] [PDF] |
||||