Fig. 2

CS protocol validation. A Diagram of NTT experimental design (1-min acclimatization + 5-min evaluation). B Virtual zones (upper, middle, and lower) of evaluation area stablished with Noldus Ethovision® XT16 software. C Kinetic parameters: velocity (cm/s) and distance (cm). D Merge (n = 9) and individual heatmaps from both experimental groups showing the minimum amount of time an individual spent in each pixel in dark blue and the maximum in red. E Time spent by males in the upper, middle, and lower zones (%). F Relative gene expression in zebrafish brain of two genes involved in endoplasmic reticulum (ER) stress: bip and chop. S⁻: control males. S⁺: males exposed to the chronic stress (CS) protocol. Data are presented as mean ± SEM (kinetics and preference data: n = 9; gene expression analysis: n = 5; fish batch 1). *p < 0.0500