Hemre GI ; Torrissen O ; Krogdahl A ; Lie O ;

Aquaculture Nutrition vol. 1 (2)   pp. 69-75, 1995

Inst. Nutr., Dir. Fish., P.O. Box 1900, N-5024 Bergen, Norway

Individually tagged Atlantic salmon, Salmo salar L., were fed three different adaptation diets containing low, medium or high levels of extruded starch, before intraperitoneal injection of glucose. The injections were done at winter and at summer temperatures. This was to investigate whether the tolerance for glucose varied according to adaptation diet and/or according to season. The results showed a temperature-dependent response. At winter temperatures (2 degree C) the Atlantic salmon had problems adapting to both medium and high levels of dietary starch. This was indicated by lower growth response in the adaptation period, as well as by delayed glucose regulation. At summer temperatures (12.5 degree C) the Atlantic salmon could tolerate and utilize both medium and high levels of dietary starch. In summer also all groups responded evenly to the tolerance tests with respect to blood glucose regulation. Incorporation of liver glycogen was higher at summer than at winter temperatures in the high-carbohydrate group. No effect was found on haematocrit values as a response to diet or season

Glucose ;  Tolerance ;  Diets ;  Adaptations ;  Water temperature ;  Temperature effects ;  Starch ;  Salmo salar ;