Abstract
Activities of lactate dehydrogenase, hydroxy butyric dehydrogenase, glutamic oxalacetic transaminase, glutamic pyruvic transaminase, glutamate dehydrogenase, creatinine kinase, alkaline phosphatase, and leucine amino peptidase were determined in the sera of rainbow trout. The animals had previously been adapted to temperatures of 3.5, 6, 8, 10, 12.5, 15, 17, 19, 21.5 and 23° C. Most of the enzyme activity increased with the rise in temperature. The activity of alkaline phosphatase decreased in the range 6–19° C, while the changes in the glutamate dehydrogenase activity took a complex course. The results are compared with the findings of other authors.