1. Clinic for Small Animals; Faculty of Veterinary Medicine; Freie Universität Berlin; Berlin Germany
2. Gastrointestinal Laboratory; Texas A&M University; College Station TX
3. Department of Production Animal Studies; Faculty of Veterinary Science; University of Pretoria; Onderstepoort South Africa
4. Institute of Animal Nutrition; Faculty of Veterinary Medicine; Freie Universität Berlin; Berlin Germany
5. Institute of Immunology; Faculty of Veterinary Medicine; Freie Universität Berlin; Berlin Germany