About the Authors
Animal Sciences Group, Wageningen University and Research Centre, Lelystad, The Netherlands
Faculty of Veterinary Medicine, Department of Farm Animal Health, Utrecht University, Utrecht, The Netherlands
Animal Health Service, Deventer, The Netherlands
The authors have declared that no competing interests exist.
MCMdJ, GJB, MvB, and TJH conceived the ideas underlying the analyses. AB, GN, and ARWE collected the data. GJB, TJH, and MvB analyzed the data and wrote the paper. AB, GN, ARWE, and MCMdJ commented on the text.