PHYSIOLOGICAL RESPONSES OF MEAGRE, ARGYROSOMUS REGIUS (ASSO, 1801), JUVENILES TO DENSITY AND TEMPERATURE

摘要

The meagre, Argyrosomus regius (Asso, 1801), is a high market value sciaenid species. For optimisation of production, it is necessary to find a balance between the maximum culture profitability and the minimum stress incidence in specimens. Density and water temperature are two important aquaculture-related stressors that induce an activation of stress system characterized by three sequential responses: i) primary (rise in plasma cortisol levels); ii) secondary (reduction of hepatic glycogen content,increased plasma glucose, reorganization of metabolite stores) and iii) tertiary (problems with growth, reproduction, immune system, etc.). Thus, a stress situation causes an increased consumption of energetic reserves for metabolism, which inevitably results in a relative decrease in growth. We analysed the influence of culture density and temperature on growth, and on plasmatic/hepatic parameters related to stress and metabolic processes. The results will be useful to determine the optimal culture combination of density and temperature for the ongrowing phase of the species.