Funding for this research was provided by:
National Science and Technology Program during the Twelfth Five-year Plan Period (2016YFD0500703-4)
Unitatea Executiva pentru Finantarea Invatamantului Superior, a Cercetarii, Dezvoltarii si Inovarii (CXZZSS2018056)
the Hebei Province Science and Technology Support Program (17226613D)
Received: 23 November 2019
Accepted: 10 May 2020
First Online: 20 May 2020
Ethics approval and consent to participate
: This study was ethically approved by the Hebei Agricultural University’s Animal Welfare and Ethical Review Board. All procedures were performed in accordance with the guidelines for the care and use of animals of Hebei Agricultural University (China) and with current Chinese legislation, following the written and informed consent of the pig farm owners.
: Not applicable.
: The authors declare that they have no competing interests.