Simulating natural chronic stress,Method of incorporation of cortisol in diet was used to study the effects of cortisol on the phagocyte respiratory burst and the serum alternative complement hemolytic activity(ACH50) of adult yellow catfish(Pelteobagrus fulvidraco). The results and conclusions are as follows.The cortisol incorporated in the diet resulted in sustained elevation of serum cortisol concentration, while there was no statistic difference among control groups. This result indicated that the metho...