Infectious diseases in wildlife threaten not only those species but also domestic animals and human health, necessitating strategies to prevent pathogen spread. The natural decomposition of carcasses may lead to pathogen inactivation due to associated increases in temperature and changes in the pH of the carcass and in the surrounding soil. In this study, the internal temperatures of 64 decomposing wild boar carcasses, the pH in the topsoil beneath 74 carcasses, and the pH of muscle and rectal tissue from 12 carcasses were monitored throughout the decomposition process. Carcass temperatures increased during decomposition, frequently exceeding 30 °C during aerobic decomposition in summer (maximum 58 °C). The pH in the carcasses increased until skeletonization, ranging from pH 4 to above pH 8. Soil pH also continuously increased during the decomposition, reaching a pH above 9 and remaining stable for at least 30 days post-skeletonization. The information on natural carcass decomposition processes provided by our study can serve as a basis for future studies to assess if elevated carcass temperatures and pH changes are sufficient for pathogen inactivation. However, our results suggest that, in most cases, neither the increase in carcass temperatures nor the changes in pH exceed the thresholds required to inactivate African swine fever virus.

Chair of Wildlife Ecology and Management Albert Ludwigs University Freiburg Freiburg Germany

Clinical unit Small Animal Surgery Department of Companion Animals and Horses University of Veterinary Medicine Vienna Vienna Austria

Department of Animal Ecology and Tropical Biology University of Würzburg Würzburg Germany

Department of Conservation and Research Bavarian Forest National Park Grafenau Germany

Department of Ecosystem Biology Faculty of Science South Bohemian University České Budějovice Czech Republic

Department of Environmental Systems Science ETH Zürich Zürich Switzerland

Department of Integrative Biology Institute of Wildlife Biology and Game Management University of Natural Resources and Applied Life Sciences Vienna Austria

Department of National Park Monitoring and Animal Management Bavarian Forest National Park Grafenau Germany

Department of Natural sciences and Environmental Health University of South Eastern Norway Bø i Telemark Norway

Department of Statistics Statistical Consulting Unit StaBLab Ludwig Maximilians Universität Munich Germany

Faculty of Applied Ecology Agricultural Sciences and Biotechnology University of Inland Norway Koppang Norway

Federal Ministry for Economic Cooperation and Development Berlin Germany

Friedrich Loeffler Institut Institute of Epidemiology Greifswald Insel Riems Germany

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