Abstract
The parasitic mite Sarcoptes scabiei causes mange in nearly 150 species of mammals by burrowing under the skin, triggering hypersensitivity responses that can alter animals’ behavior and result in extreme weight loss, secondary infections, and even death. Since the 1990s, sarcoptic mange has increased in incidence and geographic distribution in Pennsylvania black bear (Ursus americanus) populations, including expansion into other states. Recovery from mange in free-ranging wildlife has rarely been evaluated. Following the Pennsylvania Game Commission’s standard operating procedures at the time of the study, treatment consisted of one subcutaneous injection of ivermectin. To evaluate black bear survival and recovery from mange, from 2018 to 2020 we fitted 61 bears, including 43 with mange, with GPS collars to track their movements and recovery. Bears were collared in triplicates according to sex and habitat, consisting of one bear without mange (healthy control), one scabietic bear treated with ivermectin when collared, and one untreated scabietic bear. Bears were reevaluated for signs of mange during annual den visits, if recaptured during the study period, and after mortality events. Disease status and recovery from mange was determined based on outward gross appearance and presence of S. scabiei mites from skin scrapes. Of the 36 scabietic bears with known recovery status, 81% fully recovered regardless of treatment, with 88% recovered with treatment and 74% recovered without treatment. All bears with no, low, or moderate mite burdens (<16 mites on skin scrapes) fully recovered from mange (n=20), and nearly half of bears with severe mite burden (>16 mites) fully recovered (n=5, 42%). However, nonrecovered status did not indicate mortality, and mange-related mortality was infrequent. Most bears were able to recover from mange irrespective of treatment, potentially indicating a need for reevaluation of the mange wildlife management paradigm.
| Original language | English |
|---|---|
| Pages (from-to) | 434-447 |
| Number of pages | 14 |
| Journal | Journal of Wildlife Diseases |
| Volume | 60 |
| Issue number | 2 |
| DOIs | |
| State | Published - Apr 2024 |
Bibliographical note
Publisher Copyright:© 2024, Wildlife Disease Association, Inc.. All rights reserved.
Funding
The authors thank the many biologists, game wardens, veterinarians, and technicians at the Pennsylvania Game Commission, in particular Quig Stump and Andrew Di Salvo, and personnel at the University of Pennsylvania Wildlife Futures Program, that supported this research. We also thank members of the Penn State Veterinary Entomology Laboratory for their aid collecting research samples during this project, in particular Jessica Brown, Jesse Evans, Kylie Green, Taylor Miller, Alex Pagac, and Karen Poh, and Penn State Statistical Consultants for advising on data analyses. We also thank the anonymous reviewers for their constructive feedback on this manuscript. This work was supported by the Summerlee Foundation (grant 205757), and the US Department of Agriculture National Institute of Food and Agriculture and Hatch Appropriations under Hatch Project PEN04608 and accession number 1010032 (E.T.M.) and Hatch Project PEN04758 and accession number 1024904 (F.E.B.). The authors thank the many biologists, game wardens, veterinarians, and technicians at the Pennsylvania Game Commission, in particular Quig Stump and Andrew Di Salvo, and personnel at the University of Pennsylvania Wildlife Futures Program, that supported this research. We also thank members of the Penn State Veterinary Entomology Laboratory for their aid collecting research samples during this project, in particular Jessica Brown, Jesse Evans, Kylie Green, Taylor Miller, Alex Pagac, and Karen Poh, and Penn State Statistical Consultants for advising on data analyses. We also thank the anonymous reviewers for their constructive feedback on this manuscript. This work was supported by the Sum-merlee Foundation (grant 205757), and the US Department of Agriculture National Institute of Food and Agriculture and Hatch Appropriations under Hatch Project PEN04608 and accession number 1010032 (E.T.M.) and Hatch Project PEN04758 and accession number 1024904 (F.E.B.).
| Funders | Funder number |
|---|---|
| Penn State Statistical Consultants | |
| Summerlee Foundation | |
| Penn State Veterinary Entomology Laboratory | |
| University of Pennsylvania Wildlife Futures Program | |
| US Department of Agriculture National Institute of Food and Agriculture, Agriculture and Food Research Initiative | 1010032, PEN04608, 1024904, PEN04758 |
| US Department of Agriculture National Institute of Food and Agriculture, Agriculture and Food Research Initiative | |
| Sum-merlee Foundation | 205757 |
Keywords
- Control
- Sarcoptes scabiei
- epizootics
- mange
- mite
- parasitic disease
- scabies
- wildlife
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Ecology