Astaxanthin supplementation enhances low-temperature stress tolerance, immune-related genes, and resistance to Vibrio parahaemolyticus in Whiteleg Shrimp Penaeus vannamei

Whiteleg shrimp Penaeus vannamei, a highly valuable commercial species in aquaculture, is known to be susceptible to environmental stressors. In this study, we examined how dietary astaxanthin impacts the survival, behavior, and molecular responses of shrimp under acute cold stress. Shrimp were split into two groups: one fed a standard diet, the other fed an astaxanthin-enriched diet. Following feeding periods of 2 and 4 weeks, the shrimp were exposed to an acute temperature stress of 10 °C. Survival rates, behavior, and gene expression (heat shock protein [HSP]70, HSP90, hepatic lectin-like, prophenoloxidase [proPO], lysozyme, hemocyanin C chain-like, catalase [CAT], superoxide dismutase [SOD]) were studied. Astaxanthin as dietary supplement significantly improved survival under cold stress, suggesting enhanced stress tolerance. Molecular analysis showed slightly lower HSP70 and HSP90 expression in the astaxanthin group across various tissues, indicating a potential mechanism by which astaxanthin aids in stress mitigation. The astaxanthin-supplemented diet positively influenced immune and antioxidant gene expression, implying a stronger immune response and defense. These findings highlight astaxanthin’s potential to boost stress resilience and overall health in Whiteleg shrimp in aquaculture, resulting in enhanced immune responses and increased disease resistance. The results showed an effect on immunity, increasing their resistance to challenge and effectively protecting shrimp against Vibrio parahaemolyticus infection, resulting in increased resistance and high survival. Understanding these effects can contribute to better aquaculture practices, ensuring the well-being of this commercially important species in varied environmental conditions, especially in the temperate region.