Nano-selenium supplementation: improving growth, digestibility and mineral absorption in freshwater fish, Catla catla

Abstract Background This research investigated the impact of selenium-nanoparticles (Se-NPs) supplemented in sunflower meal (SM)-based diets on digestibility, mineral absorption, and growth performance of Catla catla. Se-NPs were added to seven test meals in varying amounts (0, 0.5, 1, 1.5, 2, 2.5 and 3 mgkg− 1). A total of 315 fish were evenly allocated three replicate tanks, with 15 fish per tank, and given diets equivalent to (5%) of their wet biomass daily for a period of 90 days. Results The test diet (T-D) supplemented with 1.5 mgkg− 1 Se-NPs yielded remarkable results, including a significant increase in mean weight gain (14 g), an impressive average weight gain percentage (208%), a 100% survival rate, with no mortality observed and the highest specific growth rate (1.25). Moreover, 1.5 mgkg− 1 Se-NPs (T-D-IV) demonstrated superior nutritional digestibility (CP, 76%; CF, 79% and GE, 74%). Additionally, the diet 1.5 mgkg− 1 Se-NPs showed enhanced mineral absorption (K, P, Ca, Na, Zn, Cu and Fe) than other diets. Conclusion It was practically proven that the growth indices, nutrient absorption, and mineral status of C. catla were significantly improved by Se-NPs supplemented SM-based diets, with the optimum level of supplementation being 1.5 mgkg− 1.