Abstract:
Increasing risk of pathogen spillover coupled with overall declines in wildlife population abundance in the Anthropocene
make infectious disease a relevant concern for species conservation worldwide. While emerging molecular tools could
improve our diagnostic capabilities and give insight into mechanisms underlying wildlife disease risk, they have rarely been
applied in practice. Here, employing a previously reported gene transcription panel of common immune markers to track
physiological changes,we present a detailed analysis over the course of both acute and chronic infection in one wildlife species
where disease plays a critical role in conservation, bighorn sheep (Ovis canadensis). Differential gene transcription patterns
distinguished between infection statuses over the course of acute infection and differential correlation (DC) analyses identified
clear changes in gene co-transcription patterns over the early stages of infection, with transcription of four genes—TGFb,
AHR, IL1b and MX1—continuing to increase even as transcription of other immune-associated genes waned. In a separate
analysis,we considered the capacity of the same gene transcription panel to aid in differentiating between chronically infected
animals and animals in other disease states outside of acute disease events (an immediate priority for wildlife management
in this system). We found that this transcription panel was capable of accurately identifying chronically infected animals
in the test dataset, though additional data will be required to determine how far this ability extends. Taken together, our
results showcase the successful proof of concept and breadth of potential utilities that gene transcription might provide to
wildlife disease management, from direct insight into mechanisms associated with differential disease response to improved
diagnostic capacity in the field.
