Effects of Antrodia camphorata-Supplemented Diets on the Non-Specific Immune Responses and Disease Resistance of Orange-Spotted Grouper (Epinephelus coioides) against Vibrio alginolyticus and Streptococcus iniae

Abstract

In Taiwan, the mushroom Antrodia camphorata (AC) is used for medicinal purposes, including cancer prevention and treatment. This study aimed to investigate the effect of AC-supplemented diets on the innate immunity and disease resistance of the orange-spotted grouper Epinephelus coioides against two bacterial infections—Vibrio alginolyticus and Streptococcus iniae. Orange-spotted groupers were fed AC-supplemented diets at 0 (control), 1.5, 3.0, 4.5, and 6.0 g kg−1 for 28 days and examined for innate immune responses and survival rates against V. alginolyticus and S. iniae. The results showed that the innate cellular and humoral immune parameters, including respiratory burst, phagocytic activity, and lysozyme activity of leukocytes, along with serum alternative complement activity (ACH50) and superoxide dismutase activity, as well as interleukin (IL)-4 and IL-6, were all significantly increased in groupers fed AC-supplemented diets. Groupers fed diets containing AC at doses higher than 3.0 g kg−1 had better survival rates than the control group 3–18 days after V. alginolyticus or S. iniae challenge. The enhanced disease resistance may be attributable to AC-induced innate immunity, suggesting that utilizing AC as a dietary supplement at 3.0 g kg−1 may enhance the disease resistance of orange-spotted groupers against Vibrio or Streptococcus infection.