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Chronic wasting disease (CWD) prions are notoriously resilient infectious agents that can retain infectivity in environmental settings for extensive periods of time. Given their pronounced durability and evidence of widespread prion distribution across an array of host tissues, the carcasses of CWD-infected cervids have been recognized as a potential source for ongoing transmission. Accordingly, efforts that help limit the abundance and accessibility of potentially infected carcasses on the landscape have been prioritized, with several disposal methods deemed best practices. However, the availability of effective and sustainable options for cervid carcass disposal has become increasingly limited in various parts of the country, presenting challenges to involved agencies. Thus, there is a critical need to better understand agency approaches to this issue, including any plans, practices, and perspectives. In this study, data were collected via an online questionnaire administered to recommended personnel at all 50 state wildlife agencies in the U.S. and supplemented by qualitative interviews with representatives from multiple involved state agencies in Colorado, Minnesota, and Pennsylvania. Overall, the information obtained by this effort provides valuable insight on cervid carcass disposal and its application for CWD management across the U.S. from the perspective of the numerous state-level agencies involved.

Abstract: Management of cervids for Chronic Wasting Disease (CWD) is a challenging multi-stakeholderendeavour. This thesis focuses on the thoughts and perceptions of various experts regardingcervid management in Alberta, and the inclusion of Indigenous peoples and their knowledge.This research sought to explore diverse expert perspectives on the role of Indigenous Knowledgein wildlife monitoring and management in relation to the issue of CWD; and better understandthe key challenges and opportunities regarding wildlife management in Alberta. The methodsused in this thesis include a modified qualitative expert elicitation, probabilistic sampling, andthematic analysis. The major thematic results experts discussed include: the lack of Indigenouscompliance in cervid monitoring with varying reasons provided; the necessity of both scientistsand Indigenous communities to engage in intercultural and technical capacity development; andthe need for both scientists and Indigenous communities to form a functional and mutuallybeneficial working relationship. This research is a preliminary investigation into the social,cultural, and economic aspects of CWD management, and is intended to provide further insightstowards this end with a focus on future areas of research.

Abstract: Chronic wasting disease (CWD) is a contagious prion disease spreading and emerging in wild and captive Cervidae species worldwide. Prion diseases are fatal neurodegenerative disorders occurring in various mammalian species including deer, elk, sheep, cattle and humans. Central to prion pathogenesis is the PRNP gene, which encodes the cellular prion protein (PrPC), a membrane glycoprotein that is primarily expressed in the brain. The pathogenesis of prion diseases involves the misfolding of PrPC into self-replicating, strain-encoding PrPSc (PrPCWD for cervid infections) conformers termed “prions”. Single PrPC amino acid polymorphisms can influence aspects of the disease, including susceptibility, clinical presentation and pathological phenotypes. In cervids, transmission of CWD occurs within and between species expressing PRNP allelic variants. A potential consequence of prion transmission between hosts with different PrPC primary structures is the emergence of CWD strains with novel transmission properties. These studies characterize the biological effects of CWD propagation in deer expressing different PrPC molecules: I) PrPC amino acid polymorphisms H95 and S96 subjected CWD prions to selective propagation barriers that modified the spectra of PrPCWD conformers. II) Transmission of PrPCWD conformational variants resulted in the emergence of a novel CWD strain that was selected in concert with the host recipient PrPC. III) CWD transmission between deer expressing different PrPC primary structures expanded the host range of CWD. These results suggest that circulating CWD strains would diversify as transmission between different cervid PRNP genotypes occurs. Understanding the effects of PrPC polymorphisms on the properties of CWD strains could help identify key events in their replication and spread.