764 



I'lnSIOLOCICAL STL DIES OF THE RL FEED CROiSE 



able to iiKiease their mctaliolisin snllicii-ntly to prpveiit a hrpakdowii of their temperature- 

 regulating mechanism. In this i)arti(ular instance there was a significant rlilTerence hetween 

 the averages of body temperature for males and females, beginning at the 'Mtih hour of 



fasting. 



In table 111 the body temperatures of Groups A and C are compared with those of nor- 

 mally feeding birds. The rectal temperature of Group C birds at the 84th hour of fasting 

 averaged higher for both sexes than for Group A but lower than for individuals that were 

 not subjected to fasting during these tests. The experimental data from this group demon- 

 strate the effect of both active digestion and starvation upon body temperature. Variability 

 in rectal temperature, as indicated by the magnitude of the standard error, was least for the 

 control birds and most for those individuals fasting without water. 



TABl.K 111. COMPARISON OF BODY TEMPERATURE OF FEEDIN(; GROUSE WITH 

 THAT OF GROUSE AFTER FASTINC; lil Mot US BOTH 

 WITH AND WITHOUT WATER 



♦Average caj,'*' activity. 

 ^Group A. 

 t(iroup C. 



When fasting without water, grouse apparently are subjected to rapid dehydration of body 

 tissues. The drying-up process is of such magnitude as to cause a definite increase in mor- 

 tality. The data from all groups of birds in these tests clearly indicate that grouse have 

 definite daily need for water to satisfy particular physiologic functions. Due to limited data 

 the actual cause of carlv death of grouse fasting without water is not clearly understood at 

 this time. 



Effect of Fasting on Body Weight 



Experiment 7 was supplementary to the preceding sluch and irn(il\td cLila taken coinci- 

 dental!) from the same groups of birds. Its |)urpose was to stndx liie elTcil nf fasting I both 

 with and without water) upon body weight. 



By subjecting the birds to fasting conditions the resultant data fnrnisiicd a fundamental 

 base-line of minimum vital needs for maintenance of the various physiologic functions. By 

 superimposing upon the base-line nf minimum needs the effect of such factors as muscular 

 activity, digestion of food, and air temperature, the maximum phvsiologic needs for main- 

 taining \ital functions at normal levels will be revealed. 



The 18 birds were subjected to prolonged fasting as lollcius: 



Group A — 6 grouse at 65°F.. withdut food biil with water. 

 Group B — f) grouse at lO'F.. without food but with water 

 Group C — 6 grouse at 6.S°F., without food or water 



