Digestive and antioxidant modulation by anthocyanins from Rubus spp. in black skirt tetra Gymnocorymbus ternetzi: implications for sustainable ornamental aquaculture
摘要
This study evaluated the effects of dietary supplementation with microencapsulated blackberry anthocyanin extract on pigmentation, antioxidant status, digestive enzyme activity, and histological parameters of black skirt tetra Gymnocorymbus ternetzi. Ninety juveniles were randomly distributed into nine tanks (three tanks per treatment), which were considered the experimental units: a control diet and diets supplemented with 1000 or 2000 mg kg⁻1 microcapsules for 30 days. Survival was 100%, and no differences were observed in final weight, feed intake, or viscerosomatic index; however, fish fed 2000 mg kg⁻1 exhibited a higher condition factor. Supplementation reduced lightness (L*), resulting in darker body coloration. Amylase and alkaline phosphatase activities increased significantly, while hepatic alanine aminotransferase activity decreased in supplemented groups. Histological analyses revealed improved liver architecture and increased intestinal villus height, accompanied by enhanced goblet cell activity. Antioxidant enzyme activities (SOD and CAT) decreased in supplemented groups, suggesting a modulation of antioxidant responses associated with anthocyanin supplementation. Overall, dietary inclusion of microencapsulated blackberry anthocyanins may promote enhanced pigmentation, improved digestive function, modulation of antioxidant-related biomarkers, and preservation of hepatic and intestinal integrity, supporting its use as a natural functional additive in ornamental aquaculture.