Meeting Abstract
Wild animals cope with both short-term (acute) and long-term (chronic) stressors. The glucocorticoid hormones, such as corticosterone (CORT), often facilitate such coping, but they can have quite distinct effects contingent on the duration of their elevation and subsequently the host cells and tissues they affect. Previously, we found that experimental elevation of CORT for 2 days affected responses to West Nile virus exposure in zebra finches (Taeniopygia guttata); manipulated birds had higher viremia for days longer than controls although West Nile virus (WNV)-associated mortality remained low until well after viremia had peaked. Here, we queried whether acute elevations of CORT would have similar effects or if instead elevation in just the 1h prior to exposure would instead be protective; much work in rodents has shown that short term CORT elevations can help hosts resist or cope with infection. We found that although CORT injection elevated circulating CORT to a similar degree as 2d implantation, effects on WNV outcomes were very different. Implanted individuals reached higher viremia and suffered mortality to WNV, however, the same birds were more tolerant of WNV than the other two groups and only implanted birds reached titers that could be transmitted to vectors. Our work reveals additional, yet complex, roles for CORT in avian West Nile virus dynamics.
