SEASONAL VARIATIONS IN HEMOGLOBIN AND HEMATOCRIT VALUES IN THE NORTHERN RED-BACKED MOUSE, CLETHRIONOMYS RUTILUS DAWSONI (MERRIAM), IN INTERIOR ALASKA

Abstract

Seasonal variations in hemoglobin and hematocrit values were determined in the northern red-backed mouse, Clethrionomys rutilus dawsoni, from July 1963 through August 1964 in the vicinity of College, Alaska. Hemoglobin concentrations and hematocrits did not show any significant seasonal variation. The relative constancy of the blood values was considered to be a reflection of the rather uniform thermal characteristics of the microenvironment inhabited by the mice. Mean corpuscular hemoglobin concentrations followed a cycle which varied inversely with the ambient macroenvironmental temperature, while net body weights followed a seasonal cycle which was directly correlated with the ambient temperature of the macroenvironment.