One underexplored factor that affects the food industry is the gut microbiome of animals raised for consumption. Gut microbes play big roles in how animals break down food and absorb nutrients and thus how animals grow and develop. A new study explored the links between gut microbial communities, fish feed conversion, and fish genetics in the domestic Atlantic salmon. While researchers observed weak associations between host genetics and microbial composition, they did identify bacteria linked to carbon metabolism in fat tissue and feed efficiency, as well as weight gain. The findings highlight some of the roles played by gut microbes in the metabolism of Atlantic salmon, which could affect how the fish are raised for consumption.