Thermoregulatory, metabolic and ventilatory physiology of the western barred bandicoot (Perameles bougainville bougainville) in summer and winter

Abstract

The metabolic, thermoregulatory and ventilatory physiology of western barred bandicoots (Perameles bougainville bougainville), measured in the laboratory during summer and winter at ambient temperatures of 10 and 30°C, is relatively unusual for a peramelid marsupial. It has a low thermoneutral body temperature (33.7 ± 0.2°C), a very high basal metabolic rate (0.68 ± 0.03 mL O₂ g^–1 h^–1 at ambient temperature = 30°C), low respiratory exchange ratios (often less than 0.7) and a high thermal conductance, reflecting its high oxygen consumption rate and low body temperature. Ventilatory frequency and tidal volume were variable between seasons, although minute volume and oxygen extraction efficiency were not. Minute volume of the western barred bandicoot was higher than expected, reflecting its high metabolic rate. Time of year (i.e. season) had an effect on some aspects of metabolic, thermoregulatory and ventilatory physiology (carbon dioxide production, respiratory exchange ratio, total evaporative water loss), but this effect was not as substantial nor as general as the effect of ambient temperature.