The effects of temperature and housing on water balance in a burrowing mouse,Peromyscus polionotus

Summary The effects of temperature and humidity on the water balance of two races ofPeromyscus polionotus were compared to individuals of the same race given moist sand to burrow in. Temperature had the greatest effect on fluid consumption. A change from 20 to 30°C resulted in a significant decrease in the amount of water and 0.4 M NaCl solution consumed. Generally, there was no difference in the amount of water or 0.4 M NaCl consumed at 20°C under different housing conditions, but at 30°C both races consumed significantly more fluids at the low humidity than when occupying a burrow. Considering all types of housing, temperature had a significant effect on a mouse's ability to maintain body weight when stressed with salt water. Irrespective of temperature, weight loss was less and survival greater while drinking salt water for mice in a burrow (92% survival) compared with the high (77% survival) and low (67% survival) humidity conditions.