1. Department of Animal Sciences Ruminant Nutrition, University of Göttingen Göttingen Germany
2. Institute of Agricultural Sciences, ETH Zurich Lindau Switzerland
3. AgroVet‐Strickhof, ETH Zurich Lindau Switzerland
4. Leibniz Institute for Zoo and Wildlife Research (IZW) Berlin Germany
5. Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty University of Zurich Zurich Switzerland