Introduction Fishmeal is beneficial to the growth performance of grass carp. However, it remains unclear whether fishmeal can enhance the flavor of muscle, and contribute to the regulatory mechanisms involved in its interaction with the intestinal microbiome. Methods In this study, grass carp (70.01 ± 5.34 g) were fed with diets containing 0% (FL), 3% (FM), and 6% (FH) fishmeal for 60 days. The growth performance, intestinal a...