The German Animal Welfare Act establishes minimum requirements for the keeping of animals, which also apply to zoos. The competent authorities and each zoo agree on the particular requirements for each animal species on a case by case basis. There are Expert Opinions, Guidelines and Information Leaflets for individual animal species. However it is not clear whether these documents are binding. The Expert Opinion concerning mammals published by the German Federal Ministry of Food and Agriculture does not have such widespread and generalised applicability to allow the relevant veterinary authorities or Court to forego an individualised consideration of the facts of each case. Notwithstanding this, the Expert Opinion concerning mammals does have some relevance. Single results of the expert opinion may constitute a ‘general experience’, in which case the authorities or Court may refrain from further fact finding if no existing evidence indicates that the present case is atypical.