Intestinal histology of tambaqui fed a nanocomposite consisting of Selenium, Zinc, and Schinus terebinthifolius

This study investigated the effect of dietary supplementation of nanocomposite composed of selenium (Se), zinc (Zn), and Schinus terebinthifolius extract on the intestinal histology of juvenile Colossoma macropomum. Different concentrations of nanocomposites (NC1 and NC2) were compared with inorganic supplementation (IN) after 15 and 30 days. All groups exhibited significant growth over time. Histomorphometric analysis revealed that, at day 15, inorganic supplementation promoted increases in villus height, width, and epithelial thickness. However, at day 30, this group showed a significant decrease in villus height and total villus height, and a sustained increase in villus width and epithelial thickness, indicating compromised intestinal integrity. In contrast, fish fed the nanocomposites maintained histomorphometric parameters similar to those of the control group, suggesting preservation of intestinal integrity. The index of histopathological changes showed that the histological responses induced by the nanocomposites were mild to moderate compared to the inorganic form. In conclusion, supplementation with Se, Zn, and S. terebinthifolius extract nanocomposite was effective in preserving intestinal integrity, especially at the highest concentration, indicating potential benefits for the intestinal health of tambaqui.