Affiliation: | 1. Wageningen UR Livestock Research, PO Box 65, 8200 AB Lelystad, The Netherlands;2. Dutch Udder Health Centre UGCN, GD Animal Health Service, PO Box 9, 7400 AA Deventer, The Netherlands;3. Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, PO Box 80163, 3508 TD Utrecht, The Netherlands |