Dietary Curcumin Promotes Gilthead Seabream Larvae Digestive Capacity and Modulates Oxidative Status

SIMPLE SUMMARY: The production of marine fish larvae is still recognized to have high mortality rates, so to achieve a more sustainable and competitive aquaculture industry it is essential to develop high-quality larvae. Therefore, this work evaluates if dietary supplementation of natural antioxidant curcumin enhances fish larvae robustness, hence improving growth performance and health status of the farmed fish. For that, two doses of curcumin were assessed and showed that curcumin can modulate larvae condition, digestive capacity, and antioxidant status throughout development. These results bring new perceptions of the effects of dietary curcumin in marine fish larvae that until now have not been studied. Moreover, this data suggested that curcumin can be a suitable feed additive contributing to the development and optimization of microdiets for fish larvae. ABSTRACT: The larval stage is highly prone to stress due to the ontogenetic and metabolic alterations occurring in fish. Curcumin inclusion in diets has been shown to improve growth by modulating oxidative status, immune response, and/or feed digestibility in several fish species. The aim of the present work was to assess if dietary curcumin could promote marine fish larvae digestive maturation and improve robustness. Gilthead seabream larvae were fed a diet supplemented with curcumin at dose of 0 (CTRL), 1.5 (LOW), or 3.0 g/Kg feed for 27 days. From 4 to 24 days after hatching (DAH), no differences were observed in growth performance. At the end of the experiment (31 DAH) LOW larvae had a better condition factor than CTRL fish. Moreover, HIGH larvae showed higher trypsin and chymotrypsin activity when compared to CTRL fish. LOW and HIGH larvae were able to maintain the mitochondrial reactive oxygen species production during development, in contrast to CTRL larvae. In conclusion, curcumin supplementation seems to promote larvae digestive capacity and modulate the oxidative status during ontogeny. Furthermore, the present results provide new insights on the impacts of dietary antioxidants on marine larvae development and a possible improvement of robustness in the short and long term.