Funding for this research was provided by:
the Chinese Academy of Sciences (KSZD-EW-Z-005-003)
the Key Laboratory of the Zoological Systematics and Evolution of the Chinese Academy of Sciences (O529YX5105)
Received: 22 October 2017
Accepted: 10 May 2018
First Online: 24 May 2018
Ethics approval and consent to participate
: This study was approved by the Animal Care and Use Committees of college of Life Sciences, Shaanxi Normal University. Housing and collecting of skin samples involving duck in the described experiments were carried out in strict accordance with the recommendations of the Regulations for the Administration of Affairs Concerning Experimental Animals (Ministry of Science and Technology, China, revised in June 2004). All animals used in this study were handled in strict accordance with good clinical practices and all efforts were made to minimize suffering.
: The authors declare that they have no competing interests.
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