Funding for this research was provided by:
Marcia MacDonald Rivas; UC Davis Center for Equine Health (14-04)
Received: 11 September 2017
Accepted: 4 January 2018
First Online: 18 January 2018
Ethics approval and consent to participate
: Written consent for participation was obtained from all horse owners. This study was performed in accordance with the institutional animal care and use committee at the University of California Davis (approved IACUC protocol# 18285).
: Not applicable.
: The authors declare that they have no competing interests.
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