Funding for this research was provided by:
Innovative Research Group Project of the National Natural Science Foundation of China (31970874)
Natural Science Foundation Project of Chongqing, Chongqing Science and Technology Commission (csct2018jcyjA1294)
Fundamental Research Funds for the Central Universities (SWU117061, SWU117062)
Article History
Received: 2 March 2020
Accepted: 1 June 2020
First Online: 8 June 2020
Ethics approval and consent to participate
: This study was carried out in accordance with the recommendations of the Animal Welfare Act and US Government Principles for the Utilization and Care of Vertebrate Animals Used in Testing, Research, and Training. The protocol (2018056) for evaluating bacterial colonization, immune response and protection rate was approved by Southwest University Institutional Animal Care and Use Committee.
: Not applicable.
: The authors declare that they have no competing interests.