Animal Welfare Evaluation of Wild Boar (Sus scrofa) Trapping
2018 Joint EAZWV/AAZV/Leibniz-IZW Conference
Åsa Fahlman1, DVM, VetMedLic, PhD; Johan Lindsjö2, DVM; Therese Arvén Norling2,3; Odd Höglund4, DVM, PhD; Petter Kjellander5, BSc, PhD; Erik O. Ågren6, DVM, DECVP, DECZM; Mats Stridsberg7, MD, PhD; Ulrika A. Bergvall5,8, PhD
1Swedish Biodiversity Center, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden; 2Department of Animal Environment and Health, Swedish University of Agricultural Sciences (SLU), Skara, Sweden; 3Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences (SLU), Umeå, Sweden; 4Department of Clinical Sciences, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden; 5Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Sciences (SLU), Riddarhyttan, Sweden; 6Department of Pathology and Wildlife Diseases, National Veterinary Institute, Uppsala, Sweden; 7Department of Medical Sciences, Uppsala University, Uppsala, Sweden; 8Department of Zoology, Stockholm University, Stockholm, Sweden
Wildlife traps are used in many countries with limited or no in-depth evaluation of animal welfare. Trap-capture of wild animals should be humane and ensure animal welfare, whether the animals are captured for marking, research, or hunting. Live-trap capture of wild boars is a recently introduced but disputed hunting method in Sweden, where the legal trap constructions have been approved based on pathological examinations only. For improved animal welfare evaluation, our aim was to study live trapping of wild boar in an approved corral-style trap (JP Trap). Behavioral, physiological and pathological assessments were conducted through filming of 12 capture events of 38 wild boar, blood sample analysis of the chromogranin A-derived peptides vasostatin and catestatin, and pathological examination of wild boars euthanised after live trapping. Behavioural alterations indicative of capture-induced stress (e.g., charging into the trap walls) were documented in trapped wild boars with no or minor physical injuries (e.g., skin abrasions, subcutaneous hemorrhage). Thus, capture-related injuries alone did not reflect the stress induced by live-trapping in wild boar. Single captured individuals showed more escape behaviours and reacted stronger to external stimuli than individuals captured in a group. The median (range) for catestatin and vasostatin levels were 0.91 (0.54–2.86) and 0.65 (0.35–2.62) nmol/L, respectively. In conclusion, behavioral and physiological assessments should also be included when evaluating trap constructions, to determine the stress response in captured animals, since pathological evaluation insufficiently reflects the animal welfare aspects of live trapping of wild boar.
The study was supported by the Swedish Environmental Protection Agency (SEPA) - Wildlife Management Fund (#13/279) and the Swedish Association for the Protection of Animals (Swedish: Svenska Djurskyddsföreningen). We thank Lillemor Wodmar and Bengt Röken for advice and support, Michael Gustavsson, Petter Foucard and Robert Tiblom for field support, and Sumer Lovlinger for conducting the CgA analyses. We also thank Henrik Uhlhorn, Jonas Malmsten and Gete Hestvik for conducting wild boar necropsies. Field testing of new live animal traps, including pathological assessment, was accomplished through a contract between SEPA and SLU (Contract no NV-04004-14).