Abstract

In June 2003, Zurich Zoo in Switzerland opened a new rainforest exhibit based on and linked to the Masoala National Park in Madagascar. The “Masoala Rainforest” ecosystem at Zurich Zoo exhibits on an area of 11,000 m² animals and plants from the Madagascan rainforest. The free roaming animal collection comprises representatives of 30 different species from insects (e.g., Gromphadorhina portentosa), amphibians (e.g., Dyscophus antongilii), reptiles (e.g., Geochelone gigantea, Phelsuma madagascariensis) birds (e.g., Scopus umbretta) and mammals, including different species of primates (e.g., Pteropus rodricensis, Varecia variegata rubra). Temperatures in the ecosystem vary from 18°C during night time up to 40°C during the day with an ambient relative humidity above 65%. The unique animal collection, tropical climate, possible public animal contact, size of the exhibit and semifree condition make veterinary care challenging especially in regards of zoonotic disease prevention.

The zoonotic disease prevention program in the Masoala rainforest ecosystem at Zurich Zoo regulate that all arriving animals, even animals from within the country, have to pass through a quarantine procedure according to state veterinarian regulations or an extended protocol with additional clinical and laboratory investigations. The quarantine procedure is carried out at the veterinary clinic and quarantine facility at Zurich Zoo, which is accredited by USDA and is physically separated from the zoo. In addition, animals within the exhibit are screened for potential diseases on a regular basis, especially primate faeces is examined for pathologic bacteria and parasites biannually. In cooperation with the state physician an annual health check for all employees was established and carried out by a consulting physician, specialized for zoonotic diseases. The consulting physician is also available on demand for all staff members year around and is informed about the situation within the zoo. A potential health risk was especially examined for the exhibit’s water distribution system. Standing water in puddles and water pipes for fog and artificial rain can reach temperatures between 20 to 40°C due to high environmental temperatures in the exhibition and carries an increased risk for Legionella ssp. colonization. Therefore water pipes are emptied after every use and water quality is tested within the rain/fog system, as well in the river and lake system for Legionella ssp. quarterly. Based on the current experiences the applied zoonotic disease prevention program appears effective in identifying potential pathogens during quarantine and within the ecosystem.