IBVING 



HART: You have an increase in food intake of 50% to 60%'^ 



HANNON: This is average daily intake on five huskies. 



HART: I do not think that you can conclude that this necessarily 

 represents metabolic temperature regulation. How well did you con- 

 trol activity, sledding and various things? 



HANNON: These dogs were tied with six-foot chains. They were 

 only released from these chains a few times, in both summer and 

 winter, to be brought into the laboratory for blood sugar determina- 

 tions. Furthermore, in the winter the body weight declined, and 

 in the summer it increased, thus suggesting an inability to precisely 

 match the caloric intake to the energy demands of the environment. 

 In other words, in the summer they were eating too much and in the 

 winter too little to maintain a constant body weight from season to 

 season. 



HART: Is not 60% a large increase in food intake for a well- 

 insulated animal? 



HANNON: It wouM seem so, yes. 



MORRISON: Are they rather limited in their activity in the 

 summer? 



HANNON; Grossly, the animals appeared to be most active in the 

 summer and the least active during periods of extreme winter cokl. 

 Whether this produced a significant seasonal difference is unknown. 

 It is my guess, however, that they may be more active in summer, 

 because there are more people around them. 



o 

 DURRER: It is interesting to note that in temperatures of -35 C 



or -40 C the activity is quite reduced. For example, they are even 

 reluctant to get up and eat and are not as apt to rise in the presence 

 of people at these extreme winter temperatures as they are in sum- 

 mer or in the warmer winter temperatures. 



JOHANSEN: One factor that has not been mentioned is the 



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