Excessive dietary histamine inhibits growth performance and impairs intestinal and hepatic health in juvenile American eel (Anguilla rostrata)

Introduction: Histamine commonly accumulates in animal-derived feed ingredients and is detrimental to aquaculture species, but the adverse consequences of dietary histamine remain inadequately characterized. Here, we explored the physiological influences of different dietary histamine levels on the growth performance, as well as the intestinal and hepatic health, of American eels, a fish species intolerant to histamine. Methods: , respectively. Following a 10-week feeding trial, growth performance, intestinal and hepatic morphology, antioxidant capacity, intestinal microbiota composition, and hepatic metabolites were analyzed. Results: as the maximum tolerable dietary histamine level for American eels. Conclusion: These findings provide crucial insights regarding dietary histamine levels and underscore the importance of restricting histamine content in American eel diets.