Meeting Abstract

P3.167  Tuesday, Jan. 6  Effects of chronic stress during molt on the heart rate and heart rate variability of European starlings KOSTELANETZ, Sophia A.*; DICKENS, Molly J.; BUTLER, Luke K.; ROMERO, L. Michael; Tufts University; Tufts University; Tufts University; Tufts University sophia.kostelanetz@tufts.edu

Chronic stress (CS) is the physiological condition of over-stimulation of coping mechanisms to chronically repeated noxious stimuli. Previous studies have looked at glucocorticoid levels during molt and stress. This is the first study to investigate the effect of chronic stress during molt on heart rate (HR) and heart rate variability (HRV) in captive European Starlings (Sturnus vulgaris). Each of 16 birds was implanted with a heart rate monitor to collect electrocardiograms. Three weeks after molt began, all birds were exposed to 18-days of chronic stress. Changes in HR and HRV were analyzed during two daily time periods: daytime and nighttime. Preliminary data show that during the daytime, there were no statistical changes in HR. However, HRV decreased with the onset of a molt, with no subsequent change during CS. The decrease in HRV indicates a shift from parasympathetic to sympathetic control of HR with the onset of molt, with the same balance remaining throughout CS. In contrast, during the nighttime HR goes up with the onset of molt, with no subsequent change during CS. HRV did not change both with the onset of molt and throughout CS. Because there was no decrease in HRV, the data suggests that the increase in HR is being driven by changes in parasympathetic not sympathetic input. Previous data have shown that CS has a dramatic impact on HR and HRV of non-molting birds, but here we show that molting birds have an attenuated response to CS.