Surfagon Effect on Rheoreaction of Young Brown Trout Salmo trutta

Abstract

The effect of surfagon injection (synthetic analog of gonadotropic-releasing hormone) on the kind and time of rheoreaction change in juvenile brown trout Salmo trutta is studied. In spite of the fact that the increase of gonadotropins in the organism after surfagon injection is recorded just during several hours, the action of this preparation on the rheoreaction is discovered only at the 25^th day, continues for 19 days, and is seen as the increase of the part of fish swimming upstream. The long-term effect of surfagon is found later – 5 months after the injection. This effect is present only in starving specimens and is the stabilization of their behavior in the water flow.