KLEIBER 



The thii-d point is that heat loss in the rabbit exposed to high 

 temperatures is certainly accomplished through panting. Ididsome 

 experiments wherein rabbits were exposed at 50 C (Eagan, 1961).* 

 In spite of vigorous panting by each animal, rectal temperature 

 rose steadily (after a transient slight decrease) and ear tempera- 

 ture ran between 1 C and 2 C higher than rectal temperature. 



FOLK: Is there a histological difference in the skin of the 

 Brahman cattle and the American domestic breeds? Are there 

 sweat glands in any of the cattle? 



KLEIBER: Apparently the histologists agree that there are 

 sweat glands in both breeds. 



WEST: I was interested in the caloric intake of the cows; you 

 have quite a nice curve of caloric intake as temperature falls. Is 

 this something that they just do without any forcing or do they just 

 eat this much so they can produce milk or something? 



KLEIBER: This was a theoretical, not an empirical curve. I 

 was attempting to figure out what we have to look for. 



WEST: I see, because I was wondering how you were able to 

 get cows to do this. We are trying to do this with birds. 



KLEIBER: It was just an arbitrary expression, thatthere must 

 be some limit where the temperature is too high for food intake, 

 and there must be some low temperature limit where the food intake 

 must be increased. I drew a curve against these two limits. 



WEST: In other words, you think of it as a curve, not as a 

 straight line more or less paralleling the resting metabolism or 

 heat requirement? 



KLEIBER; Well, it could be a straight line, perhaps, but I do 

 not see how. 



*Eagan, C. J. 1961. Topical adaptation to cold in the rabbit ear. Fed. Proc. 

 20, No. 1, Part 1:210. 



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