Funding for this research was provided by:
Svenska Forskningsrådet Formas (221-2012-667)
European Research Council (322206)
Carl Tryggers Stiftelse för Vetenskaplig Forskning (12:546)
Received: 3 July 2017
Accepted: 8 January 2018
First Online: 23 January 2018
: The animal studies were approved by Jordbruksverket (Swedish Animal Ethics board), with ethical permit Dnr 122–10.
: Not applicable.
: The authors declare that they have no competing interests.
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