Astaxanthin in Aquaculture: Enhancing abalone health through oxidative stress management

Oxidative stress is one of the most important physiological stressors observed in aquaculture, particularly in species such as abalone (Haliotis spp), whose metabolic properties and environmental stressors render them vulnerable to reactive oxygen species (ROS). Overproduction of ROS can damage cells, impairing immune responses and growth performance in aquaculture species. This review summarizes the importance of antioxidant defense mechanisms, especially enzymatic and non-enzymatic systems, in reducing oxidative stress in abalone. Astaxanthin, a potent carotenoid antioxidant from microalgae and other marine sources, is the main active ingredient in managing oxidative stress. Astaxanthin acts as a potent scavenger of free radicals, stimulating antioxidant enzyme activity and modulating immune responses, thus boosting general physiological stress resistance in abalone. In addition, dietary astaxanthin supplementation has been shown to improve growth performance, increase survival rates, and develop pigmentation, thereby increasing the market value of abalone. It also discusses the absorption, metabolism, and best dietary approaches for astaxanthin supplementation. Although it offers advantages, cost-effectiveness and formulation optimization are still important barriers to its broad implementation in aquaculture. Further studies should focus on optimizing astaxanthin production, the prolonged physiological effects of astaxanthin, and the cost-effective formulation of astaxanthin-rich diets that could be adopted in the sustainable farming of abalone.