Article History
Received: 5 April 2018
Accepted: 28 June 2018
First Online: 11 July 2018
Ethics approval and consent to participate
: Animals were housed and cared for in accordance with the committee for the assessment of laboratory animal care standards and the guidelines of Tokyo University of Agriculture. This animal study was approved by the Ethics Committee of the Tokyo University of Agriculture. Care of gnotobiotic mice and collection of samples were operated by Sankyo Labo Service Co. (Tokyo, Japan). This experimental design was approved by the ethical committee of the company.
: Not applicable.
: The authors declare that they have no competing interests.
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