Effects of changing ambient temperature on metabolic, heart, and ventilation rates during steady state hibernation in golden mantled ground squirrels(Spermophilus lateralis)

To determine whether metabolic rate is suppressed in a temperature-independ ent fashion in the golden-mantled ground squirrel during steady state hiber nation, we measured body temperature and metabolic rate in ground squirrels during hibernation at different T-a's. In addition, we attempted to determ ine whether heart rate, ventilation rate, and breathing patterns changed as a function of body temperature or metabolic rate. We found that metabolic rate changed with T-a as it was raised from 5 degrees to 14 degreesC, which supports the theory that different species sustain falls in metabolic rate during hibernation in different ways. Heart rate and breathing pattern als o changed with changing Ta, while breathing frequency did not. That the tot al breathing frequency did not correlate closely with oxygen consumption or body temperature, while the breathing pattern did, raises important questi ons regarding the mechanisms controlling ventilation during hibernation.