Have you ever had the experience of having a fish that suffered a stress attack and ended up dying?
My experience leads me to believe that when fish are stressed, they swim around the aquarium completely out of control, with clearly visible "stress bars," hitting the glass and sometimes, after losing all energy, lying on the bottom of the aquarium or hiding, breathing with great difficulty. Frequently, their eyes droop from swimming sideways and scratching their retinas on the bottom of the aquarium, which is due to an excess of one of their hormones, cortisol. In Discus, cortisol is the main hormone associated with the physiological stress response. Empirically, and before talking and discussing with different biologists, I always thought it was a hormone produced in the fish's brain, but in reality, it is not, contrary to my theory. The stimulus of catching a fish with a net and capturing it, its transport, lack of oxygen, sudden changes in water, or territorial conflicts are perceived by the nervous system located in the brain. This stimulus in the brain activates th...
