Respiratory plasticity during acclimation to hypoxia and following a recovery in normoxia

Phenotypic plasticity manifested after acclimatization is a very important source of biological variability among fish species. We hypothesized that hypoxic acclimation, besides potentially generating temporary respiratory phenotype, would also manifest as continued benefit reacclimation to normoxia. Hence, we holistically characterized the phenotype European sea bass ( Dicentrarchus labrax (Linnaeus, 1758)) acclimated normoxia with or without prior acclimation hypoxia. Compared original normoxic hypoxia and return produced 27% higher absolute aerobic scope (AAS), 24% citrate synthase activity in red muscle, 28% lower excess post exercise O 2 consumption. Additional testing hypoxia-acclimated under explored specific effects acclimation. The when compared had standard metabolic rate, better performance, minimum PO for supporting 50% AAS. Thus, allows improve its maximum capacity returning from potential exploiting habitat. Given this malleability, general predictions marine more future should consider prolonged exposures.