Endothermy and Ectothermy in Mice at ~3°c
نویسنده
چکیده
A study is being made of the effects on laboratory mice (Mus musculus L.) of breeding at an environmental temperature of — 2 to — 4 C. It has been found that both A (white) and C57 (black) mice, rigorously inbred, can be maintained indefinitely at this temperature, given cotton-wool for nesting (Barnett & Manly, 54)In general, adjustment to a low temperature may be of two kinds: (a) internal changes (endothermic), such as raised heat production or improved thermal insulation; (b) alteration of the environment of the animal (ectothennic), for instance nest-building or moving to a warmer place. This paper describes some observations on the combination of endothermic and ectothermic adjustments by which mice maintain themselves at — 3 C.
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