Received: 9 February 2018
Accepted: 29 May 2018
First Online: 26 June 2018
: This study was conducted in compliance with local and national regulations and was approved by the Merck Animal Health Ethics Committee.
: PF is an employee of MSD Animal Health, FG and FS are employees of Merck Animal Health.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.