STATISTICS OF NUTRITION. 677 



than the amount of albumen in the preceding diet in determining the 

 degree of albumen destruction in the first days of starvation, and that 

 the albumen destruction from starvation is dependent upon two 

 causes : — 



1. A very variable one, which only acts in the first days and which 

 is dependent on the preceding diet and the general condition of the 

 body. 



2. A constant cause, which alone remains in force after the cessa- 

 tion of action of the first. 



The following table shows how the amount of urea excreted 

 increases with the amount of nitrogenous matter in the preceding 

 meals : — 



Food given Before 



CJrea in Last Day 



Urea in Fir 



Starvation. 



of Feeding. 



of Fasti 



2500 grammes meat, 



180.8 



60.1 



2000 " 



142.9 



33.6 



1500 " " . . . . 



110.8 



29.7 



800 " " and 200 grammes fat, 



51.8 



19.8 



Decreasing amount of meat on last day 







176 grammes, 



26.2 



16.9 



Abundance of fat after starvation, 



16.1 



15.4 



Voit concludes that animals possess, first, a considerable available 

 " store " of albumen, which is capable of being increased by a previous 

 meal rich in albuminoids and which is again rapidly removed in any 

 drain on the economy ; and, second, a much larger amount of proteid 

 matter, which represents all the proteids of the animal body and 

 which he terms "tissue-albumen." Of this latter but a small portion 

 comes under the conditions of decomposition. The rapid fall in elimi- 

 nation of urea in starvation depends upon the using up of the " stored " 

 albumen; when, however, this is all consumed, then the tissue-albumen 

 in its turn undergoes destruction. Of course, the stored-up albumen is 

 also located in the various tissues. 



Herbivora contain in their tissues a lesser amount of this stored- 

 up or reserve albumen than do the carnivora ; even the tissue-albumen 

 is present in relatively smaller amount. Thus, it has been found that a 

 full-grown ox during starvation will only use up 1.27 kilos of proteids, 

 while, measured by the albuminoid waste in carnivora, at least double the 

 amount of nitrogenous excretion products might be expected. 



In addition to the influence of these amounts of albumen on the 

 proteid waste of fasting animals, the amount of fat in the animal body 

 is also of moment; the greater the amount of fat, the less the nitrogenous 

 waste, and this holds whether the fat is already stored up in the economy 

 or is given to thin animals in the food. 



Voit, by giving one thousand five hundred grammes of meat daily 

 to a dog, brought it to a nutritive condition in which the excretion of 



