Channel catfish ( Ictalurus punctatus ), a significant aquaculture species, occupies a prominent position in the aquaculture industry due to its rapid growth, excellent adaptability, and economic value; however, the hemorrhagic disease caused by Aeromonas hydrophila has had a substantial impact on its cultivation. Researches have indicated that cortisol, the main stress hormone, is essential for regulating immune responses. Therefore, in this study, the immune regulatory effects of cortisol on the spleen tissue under Aeromonas hydrophila stimulation were analyzed. Through transcriptomic (RNA-s...