Meeting Abstract

64.3  Monday, Jan. 6 08:30  Effects of thermal stress on cellular physiology of winter-acclimated House Sparrows. JIMENEZ, AG*; WILLIAMS, JB; The Ohio State Univ. jimenez.102@osu.edu

Given that our climate is rapidly changing, Physiological Ecologists have the critical task to identify characteristics of species that make them either resilient or susceptible to changes in their natural air temperature regime. Birds are important bio-indicators of detrimental effects of global climate change. Air temperature not only affects the metabolic rate of birds, but also exerts other indirect and direct such as their food supply, and the timing of breeding. The implications of climate change for birds have only recently begun to be addressed and there is already compelling evidence some of species have been impacted by recent climate change. We have explored whether short-term thermal stress at the whole animal level might alter cellular rates of metabolism. We collected winter acclimatized House Sparrows, Passer domesticus, during January and February of 2013 in Ohio. We separated 14 birds into a “control” group of 7 birds that was promptly sacrificed after collection, and a “heat shocked” group that was acclimated to 43 ºC for 24 hrs and then sacrificed. Skin from both groups was collected and primary dermal fibroblasts were grown. We predicted that cells from the control group would have lower rates of metabolism than fibroblasts from heat shocked animals. We found that oxygen consumption rates (OCR), measured using a Seahorse XF 96 analyzer, were significantly higher in the heat shocked group of House Sparrows compared with their winter acclimated counterparts. Additionally, we also measured cellular rates of glycolysis and glycolytic capacity and found that heat shocked birds had higher rates for both parameters as well. These results lead us to believe that whole-animal responses to increases in temperature can be translated down to the cellular level in birds.