Recovery of the brown trout, Salmo trutta L., from acute handling stress: a time-course study

The response of the brown trout to a single, short (c. 1 min) incidence of handling stress was monitored for a period of 1 month post-stress. Significant changes were found in feeding behaviour, in the levels of plasma cortisol, glucose and lactate, in the concentration of circulating lymphocytes and in the degree of epidermal mucification. No changes were detected in the growth rate and coefficient of condition, in the levels of plasma thyroxine, in the concentrations of circulating erythrocytes, neutrophils and thrombocytes or in the thickness of the epidermis. The time-course for recovery of each parameter was examined and from this it was concluded that a minimum of 2 weeks was required for complete recovery and a return to normality.