Abstract Bacillus species are spore-forming bacteria with characteristics that support their use as probiotics; however, the effects of combined Bacillus subtilis and Bacillus amyloliquefaciens supplementation on intestinal and immune outcomes have been minimally studied in dogs. This study evaluated fecal characteristics, microbiota, fecal immunoglobulin A and calprotectin concentrations, serum chemistry, hematology, and immune function in healthy adult dogs supplemented with B. subtilis and B.
