A villus expanding agent of an animal including human is provided to improve digestion by promoting the expansion of the villus of the small intestine. A villus expanding agent of an animal comprises lactic acid bacteria(provided that EGF producing recombinant lactic acid bacteria are excluded), a killed body thereof and a treated material thereof as effective ingredients, wherein the lactic acid bacteria are microorganisms of an Enterococcus sp. and they are administered orally or nasally. Further, the microorganisms of an Enterococcus sp. are Enterococcus faecalis.