Funding for this research was provided by:
U.S. Department of Agriculture (USDA-ARS 3062-51000-051-00D, USDA-ARS 3062-51000-053-00D)
Received: 9 April 2018
Accepted: 3 July 2018
First Online: 10 July 2018
Ethics approval and consent to participate
: This study uses publically available secondary data, and was deemed exempt by the University of North Dakota Institutional Review Board.
: Not applicable.
: The authors declare that they have no competing interests.
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