Meeting Abstract
Co-infection with helminth parasites (e.g. gut worms) and microparasites (bacteria or viruses) is often the natural state for wild animals. Although murine models have shown that gut helminths can bias immune responses away from inflammatory processes, few studies have examined the role that helminths play modulating immunity in free-living, wild vertebrates. Here, we used anthelminthic drugs to treat free-living song sparrows (Melospiza melodia) for helminth infections (“de-wormed” birds) and measured markers of systemic inflammation (heterothermia and activity level) to an immune challenge induced using lipopolysaccharide (LPS), a nonreplicating cell-wall component of gram negative bacteria. We attempted two non-invasive methods of confirming helminth infection status, fecal flotations and 18S amplicon sequencing. Skin temperature and activity level were monitored remotely using automated radio telemetry in the field. Because helminths can reduce inflammation, we predicted that in comparison with control birds (birds not treated for helminth infection), de-wormed birds would be less active and display higher fevers when challenged with LPS. In contrast, initial analyses suggest that de-worming had no effect on thermoregulation, and that LPS-injection decreased birds’ activity regardless of anthelminthic treatment. These results suggest that natural helminth infection may not bias bird immune response away from whole-body inflammation, though such patterns may depend on tissue tropisms and other characteristics of specific co-infecting organisms.
