鱼类对碳水化合物的利用.pdf

Aqlmculture ELSEVIER Aquaculture 124 ( 1994) 67-80 Review Utilization of dietary carbohydrate by fish R.P. Wilson Department of Biochemistry and Molecular Biology, MississippiState University,MississippiState, MS 39762, USA Abstract The nutritional value of carbohydrates varies among fish with warmwater fish being able to utilize much higher levels of dietary carbohydrate than coldwater and marine fish. No dietary requirement for carbohydrate has been demonstrated in fish; however, if car- bohydrates are not provided in the diet, other nutrients such as protein and lipids are catabolized for energy and to provide metabolic intermediates for the synthesis of other biologically important compounds. Thus, it is important to provide the appropriate level of carbohydrate in the diet of the fish species being cultured. The relative use of dietary carbohydrates by fish varies and appears to be associated with the complexity of the car- bohydrate. For example, certain species have been shown to utilize simple sugars as well as, or better than, complex carbohydrates whereas other species do not utilize simple sug- ars as an energy source. Most species utilize cooked starch better than raw starch. Oral glucose tolerance tests result in persistent hyperglycemia in fish. This prolonged hypergly- cemia and the relative inability of fish to utilize high levels of dietary carbohydrates has been assumed to be the result of low levels of endog