As freshwater resources become increasingly limited, exploiting brackish and marine waters for aquaculture is viewed as a promising alternative. Nile tilapia (Oreochromis niloticus), although considered euryhaline, shows relatively restricted tolerance to salinity compared with other tilapia species, making it an ideal model to study adaptive responses to osmotic stress. Serotonin (5-HT) and dopamine (DA) are key modulators of...