TURMELLE, Amy S.*; ALLEN, Louise C.; SCHMAEMAN, Cynthia; MENDONCA, Mary T.; KUNZ, Thomas H.; MCCRACKEN, Gary F.; University of Tennessee, Knoxville, TN; Boston University, Boston, MA; Auburn University, Auburn, AL; Auburn University, Auburn, AL; Boston University, Boston, MA; University of Tennessee, Knoxville, TN: Ecological Effects of Innate and Adaptive Immune Function in Brazilian Free-tailed Bats (Tadarida brasiliensis).

This study examines both innate and adaptive immune function in wild populations of Brazilian free-tail bats in south-central Texas. With increasing numbers of bats inhabiting bridges and residential roosts, it is important to investigate the health of bats occupying man-made structures relative to those using natural roosts. Existing data suggest that Brazilian free-tail bats may switch roosts from year to year, and as such, we expect no significant variation in innate immune function across sites. However, a higher frequency of potential stressors in bridge roosts (e.g. noise, vibration, and toxins) may compromise adaptive immune response in individual bats. We tested these hypotheses with Brazilian free-tail bats captured from four different sites (two caves and two bridges) by quantifying bactericidal ability of blood and an in vivo T cell response to an antigen challenge. Preliminary data suggest significant site and roost type variation in innate immunity, with bats at bridges showing lower bactericidal ability than bats in caves. Additionally, there was significant site and roost type variation for adaptive immune response, with bats from caves exhibiting a significantly greater T cell response than bridge-roosting bats. Neither sex, age, nor reproductive condition, compared within sites, were consistent predictors of variation in bactericidal ability or T cell response. These results will also be discussed in the context of stress endocrinology and epidemiology of free-tail bats in south-central Texas.