Enhancement of Non-specific Immune Responses in Giant Grouper Epinephelus lanceolatus via Dietary Administration of Antrodia camphorata Extract (ACE) and Protection Against Grouper Iridovirus Infection

Giant grouper, Epinephelus lanceolatus in Taiwan are affected by diseases caused mainly by the members of the iridovirus and nervous necrosis virus; consequently, the increase in mortality rate of the groupers has resulted in major losses in their production, consequently threatening the commercial grouper industry. Antrodia camphorate-containing several bioactive compounds-is used for medicinal purposes including cancer prevention and treatment. In this study, the effects of A. camphorata extract (ACE) on the innate immune responses and disease resistance in giant groupers against grouper iridovirus (GIV) were examined after subjecting the groupers to diets with different levels of ACE for 14 days. After GIV infection, groupers that were fed diets with ACE doses higher than 1.5 g/kg revealed higher survival rates than that of control groupers that did not receive any ACE. The innate immune parameter values-determined after 14 days of ACE administration-were also significantly higher in groupers fed ACE-supplemented diets compared to those of the control groupers. The enhanced disease resistance of the giant groupers to GIV may be attributable to the ACE-induced innate immunity, whereas ACE showed significant anti-GIV infection activities in a dose-dependent manner, thus emphasizing the significance of ACE as a potential therapeutic for giant groupers against GIV infection.