Received: 14 August 2018
Accepted: 20 November 2018
First Online: 26 November 2018
Ethics approval and consent to participate
: The blood samples were taken by the responsible farm veterinarian in the context of the health-monitoring program of the farm under the control of the Bovine Health Service (Chamber of Agriculture for North Rhine-Westphalia, Bad Sassendorf). No permissions were necessary to collect the specimens used in the study.
: A written informed consent to use the animals in the study was obtained from the owner of the animals.
: The authors declare that they have no competing interests.
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