772 



PHYSIOLOGICAL STUDIES OF THE RUFFED GROUSE 



prolonged fast previously described (Experiment 7) were given the same rations as above 

 and were studied similarlv for five days at an air temperature of 65°F. The observational 

 data are recorded in table 117. This study immediately followed ten consecutive days of 

 living without food during which all the birds lost weight. Despite the daily ingestion of 

 food during the 5-day period, four birds (Group B) continued to lose weight. The remain- 

 ing six, however, gained. The average trends in body weight during the periods of fasting 

 and recovery are shown in figure 94. It will be noted that the caloric value of the food eaten 

 per day by the birds in Group B was considerably below that of Group A. Also, the former 

 group averaged heavier at the beginning of the fasting period, but lost a somewhat greater 

 proportion of their initial weight before again being given food. 



As shown in figure 9.'i, Group A was again weighed at the end of 13 days. The rate of 

 recovery was about three times faster during the first five days than during the remaining 

 eight. At the end of this period these birds, after losing about 19 per cent of their initial 

 weight while fasting had recovered only 65 per cent of the loss and therefore were still about 

 6 per cent below their initial weight. 



I 620 



Group A 

 Group B 



< 



o 



I- 



^ 520 1 

 UJ 



5 



>- 

 a 



O 500 



m 



540 



ELod ot Ta»tirtq period 



n 



DURATION OF TEST IN DAYS 



FIGURE 95. COMPARATIVK TKENOS IN BODY WEK-IIT AMONG TWO GROl PS OF ADIT.T GROISE 



DURING PERIOD OF FASTING AND FOLLOWING SUBSEQUENT INGESTION OF FOOD 



The consistent gain of certain birds was due chiefly to a larger daily food and water 

 intake. Such birds would recover their nitrogen balance quicker after fasting than ones 

 which ale less food. Furthermore, the more protein eaten the more rapid the replacement of 



