Efficacy of probiotic exposure during the early developmental stages of steelhead trout (Oncorhynchus mykiss)

Probiotics, such as Bacillus subtilis, have been shown to benefit the host organism. Seeding of intestinal tracts within fish begin early in their life cycle, but probiotic exposure during the early life cycle of steelhead trout has been understudied. A high concentration of a proprietary strain of Bacillus subtilis was top-coated onto the feed and fed to the fish and compared to a control diet. The microbiome is a vital resource for its fish host, so the 16S rRNA gene V4 region was sequenced from the internal homogenates of steelhead trout throughout the study.