Received: 30 January 2019
Accepted: 3 June 2019
First Online: 17 June 2019
Ethics approval and consent to participate
: The study design followed ethical guidelines of the University and procedures on healthy dogs were approved by the authorities of Lower Saxony (animal experiment number 33.9-42502-05-14A453). The samples included in the study were taken as part of the standard care. Owners of each dog gave consent for their dog to be included in the study. The consent was sufficient, according to the ethical guidelines of the University of Veterinary Medicine Hannover, Foundation.
: Not applicable.
: The authors declare that they have no competing interests.