PREVITE AND BERRY 



difference after 24 hours. Therefore, my findings would essen- 

 tially agree with those of Dr. Miya. That is, within 24 hours, 

 the body temperature of control animals exposed to 5° C returns 

 to the normal range, 



SCHMIDT: You have essentially shown us that you can take 

 a group of ten animals and leave them at 25° C, and their average 

 rectal temperature is going to drop 1° C, 



PREVITE: It is not one complete degree. It's a fraction of a 

 degree. Again, if one compares the figures 37.8° C versus 36,6° C 

 alone, they do seem to differ significantly. However, upon sta- 

 tistical analysis they are not significantly different because of 

 the wide mean deviation and overlap between them, 



BERRY: I would like to comment first on Mr, Schmidt's question. 

 It is very relevent. It seems a little peculiar, when you look 

 at the cold figures, to find temperature differences, but it may 

 be just a statistical fluke. Mice show variations in temperature 

 during the day, and particularly, with time of day. This is a well 

 known fact, Afound 4:00 a,m,, or at least early morning, the tem- 

 perature is typically a full degree lower than it is in the after- 

 noon. This has been studied extensively by people interested in 

 biological clocks. Now, with any group of mice, in order to es- 

 tablish a change in body temperature with time of day, it is 

 necessary to work with large numbers of animals and to main- 

 tain, if possible, a constant environment. With a small sample 

 of mice, it may be possible to get nearly a degree's tempera- 

 ture average difference just because of a sampling anomaly, 



WALKER: I think you can get as much of a temperature difference 

 as that and more in addition to that with just a little bit of activity, 



BERRY: Yes, and you probably change their temperature with 

 rectal probes, 



WALKER: Wisconsin mice don't like a rectal probe at first, 

 and they usually struggle, which will run the body temperature 

 up. If you let them struggle and keep the probe there, you can 

 follow his temperature climb. If you take ten mice in a group 



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