Funding for this research was provided by:
Bundesministerium für Ernährung und Landwirtschaft (2873MDT903)
Received: 21 June 2017
Accepted: 19 June 2018
First Online: 27 June 2018
: All animal experiments were performed under approval of the Lower Saxony State Office for Consumer Protection and Food Safety (reference number 09/1714) regarding internationally accepted veterinary standards and federal guidelines. All animals from the field study were stunned during the marketing process of the farms. The farmers agree with their participation in the field study.
: Not applicable.
: The authors declare that they have no competing interests.
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