温度与聚群对三种仔兽热能代谢的影响

仔兽出生以前,是在相对稳定而安全的母兽子宫内生活的,出生以后,仔兽的营养条件与环境温度即起了根本的变化。新生仔兽是如何适应新环境的?仔兽在新环境中的生活能力怎样?环境温度与食物条件对新生仔兽的存活率、生长与发育的影响如何?环境温度和聚群行为与能量代谢的关系怎样?这是一系列的基础理论问题,尤其是毛皮动物饲养业所关心的实际问题。

THE EFFECT OF THE HUDDLING AND AMBIENT THERMOREGULATION ON HEAT ENERGY METABOLISM OF NEWBORNS OF FUR ANIMALS

1. The paper reports the effect of the 3 or 4 animals of a huddling and ambient temperatures(from 15℃ to 33℃)on heat energy metabolism and thermoregulation of newborns of three species' fur animals,viz.weasels(Mustela sibirica)3-35-day-old, 1-44-day-old minks(Mustela vison)and 1-24-day-old domestic rabbits.2. The heat energy metabolism of the newborns were measured under a simple closedsystem respirameter.3. The body temperatures of the newborns rose or fell with ambient temperatures until they reached homeothermic days old(Figs. 1 to 3 ),but the heat energy metabolism (cal/g/day) increased with the ambient temperatures falling (Figs. 4 to 6 ). The increased extra heat energy was not enough to maintain the steady body temperature level during the falling of ambient temperature.4. The homeothermic ability of newborns of the three species increased with their age(Figs. 1 to 3 ).5. (1) Exposed to coldness the body temperatures of the huddling of newborns were higher than singles(Figs 1 to 3 ):For rabbits of l-18-day-old,the average body temperature of a huddling was higher by 1.09℃,0.5℃ and 0.3℃ under ambient' temperatures of 15℃, 25℃ and 33℃ respectively than singles;Minks (Mustela visora)l-44-day-old, the average body temperatures of a huddling was higher by 2 ℃ and 0.72℃ than singles under 22℃ and 26℃ respectively.Weasels(Mustela sibirica) 3 -35-day-old,the average body temperatures of a huddling was higher by 1.38℃ and 0.97℃ than singles under 22℃ and 25℃ of ambient temperatures respectively. (2) But the heat energy metabolism (cal/g/day)of a huddlirg is lower than the single when exposed to coldness(Figs. 4 to 6 ):Rabbits l-6-day-old,the average heat energy metabolism(cal/g/day) of a huddling was lower by 35.02% and 37.75% than singles urder 25℃ and 33℃ of ambient temperatures respectively.Minks (Mustela vison) 1-40-day-old, the average heat energy metabolism (cal/g/day)of a huddling was lower by 40.68% and 46.95% than singles under 22℃ and 26℃ of ambient temperature respectively.Weasels(Mustela sibirica)3-35-day-old,the heat energy metabolism(cal/g /day)of a huddling was lower by 39.45% and 27.41% than singles under 22℃ and 25℃ of ambient temperature respectively.6. It is an ecological strategy that any uneffective extra energy consumption of the newborns should decrease in their huddling or in a warm nest.