Combined Effects of Dietary Astaxanthin and β-Carotene on Antioxidant Status, Pigmentation, Muscle Quality, and Flavor Profile in Male and Female Macrobrachium rosenbergii

Abstract

Carotenoid nutrition plays a crucial role in crustacean aquaculture by regulating antioxidant defense, pigmentation, physiological performance, and edible quality. This study evaluated the combined effects of dietary astaxanthin and β-carotene on antioxidant status, pigmentation, muscle quality, and flavor profile in male and female Macrobrachium rosenbergii. Seven isonitrogenous and isolipidic diets were formulated, including a carotenoid-free control and six diets supplemented with different astaxanthin and β-carotene combinations. After a 77-day feeding trial, growth performance, antioxidant parameters, digestive enzyme activities, carotenoid deposition, body coloration, muscle texture, free amino acids, flavor nucleotides, equivalent umami concentration, and volatile flavor compounds were systematically assessed. Dietary carotenoid supplementation improved growth performance in both sexes, although the response patterns differed between males and females. In males, astaxanthin contributed more prominently to growth and several physiological traits, whereas in females, astaxanthin, β-carotene, and their interaction significantly affected multiple response variables. Carotenoid supplementation enhanced antioxidant capacity, carotenoid deposition, body redness, muscle texture, and flavor-related traits. GC-IMS analysis further revealed sex-dependent remodeling of volatile flavor profiles under different carotenoid combinations. Among all treatments, the combined high-dose diet containing 160 mg/kg astaxanthin and 160 mg/kg β-carotene showed the best overall performance in both sexes. These findings indicate that dietary astaxanthin and β-carotene combinations exert compound- and sex-dependent effects in M. rosenbergii and provide a basis for developing sex-specific functional feeds.