Short- and long-term effects of dietary l-tryptophan supplementation on the neuroendocrine stress response in seawater-reared Atlantic salmon (Salmo salar)

► Effects of dietary l-tryptophan on stress reactivity was examined in Atlantic salmon. ► l-tryptophan evoked an acute stimulatory and delayed inhibitory stress response. ► Dopamine activity was more affected by l-tryptophan than serotonin activity.