Journal of Applied Physiology, Vol 43, Issue 1 121-125, Copyright © 1977 by American Physiological Society
Effect of cold exposure on water requirements on three species of small mammals
D. R. Deavers and J. W. Hudson
Water turnover rate (WTR) was determined from tritiated water (3H2O) loss
in the short-tailed shrew (Blarina brevicauda), red-backed vole
(Clethrionomys gapperi), and white-footed mouse (Peromyscus leucopus). When
given ad libitum water at Ta of 20 degrees, B. brevicauda, C. gapperi, and
P. leucopus turned over 16.2, 13.8, and 6.2 ml/day, respectively; minimum
WTR was 9.9, 7.8, and 3.5 ml/day, respectively. When they were given ad
libitum water at 5 degrees C, WTR was 1.4 to 1.6 times higher than at 20
degrees C. On minimum water rations, WTR at 5 degrees C was 1.7 to 1.9
times higher than at 20 degrees C. Since increases in VO2 at 5 degrees C
and at 20 degrees C were of about the same magnitude, increased metabolic
rates may have caused increased water requirements. Total body water (TBW)
was calculated from 3H2O dilution. On minimum water rations, the three
species at both Ta's showed decreases in TBW and body weight, but percent
body H2O increased.
