1. Zoo Duisburg AG, Department of Zoo Veterinary Medicine, Duisburg, Germany
2. Institute of Animal Nutrition, University of Zurich, Zurich, Switzerland
3. Kölner Zoo, Department of Zoo Veterinary Medicine, Köln, Germany
4. Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
5. Biochemical Genetics Laboratory, CHU Sart Tilman, University of Liège, Liège, Belgium
6. IDEXX Laboratories, Ludwigsburg, Germany