362 



1. Fat, . 



2. Spleen,* 



3. Liver, 



4. Testicles, 



5. Muscles, 



6. Mood, 



7. Kidneys, 



8. Skin, . 



9. Intestine, . 

 There is a very important difference according as the animals before inanition 



have been fed freely on flesh and fat [i.e., if they have a surplus store of food 

 within themselves], or as they have merely had a subsistence diet. Well-fed 

 animals lose weight much more rapidly during the first few days than on the later 

 days. V. Voit thinks that the albumin derived from the excess of food occurs in 

 a state of loose combination in the body as "circulating" or "storage-albumin" so 

 that during hunger it must decompose more rapidly and to a greater extent than 

 the ''organic albumin," which forms an integral part of the tissues ( 236\ 

 Further, in fat individuals, the decomposition of fat is much greater than in slender 

 persons. 



238. METABOLISM ON A PURELY FLESH DIET. A man is not able to 

 maintain his metabolism in equilibrium on a purely flesh diet ; if he were compelled 

 to live on such a diet, he would succumb. The reason is obvious. In beef the 

 proportion of nitrogenous to non-nitrogenous elementary constituents of food is 

 1 : 1 *7 (p. 357). A healthy person excretes 280 grammes [8 to 9 oz.] of carbon in the 

 form of CO.,, in the expired air, and in the urine and fa?ces. If a man is to obtain 

 280 grammes C from a flesh diet he must consume digest and assimilate more 

 than 2 kilos. [4*4 lbs.] of beef in twenty-four hours. But our digestive organs are 

 unequal to this task for any length of time. The person is soon obliged to take 

 less beef, which would necessitate the using of his own tissues, at first the fatty 

 parts and afterwards the proteid substances. 



A carnivorous animal (dog), whose digestive apparatus, being specially adapted for the 

 digestion of flesh, has a short intestine and powerfully active digestive fluids, can only main- 

 tain its metabolism in a state of equilibrium when fed on a flesh diet free from fat, provided its 

 body is already well supplied with fat, and is muscular. It consumes -fa to ^ T part of the 

 weight of its body in flesh, so that the excretion of urea increases enormously. If it eats a 

 larger amount, it may " put on flesh," when, of course, it requires to eat more to maintain itself 

 in this condition, until trie limit of its digestive activity is reached. If a well-nourished dog is 

 fed on less than ^ to -fo of its body-weight of flesh, it uses part of its own fat and muscle, 

 gradually diminishes in weight, and ultimately succumbs. Poorly fed, non-muscular dogs are 

 unable from the very beginning to maintain their metabolism in equilibrium for any length of 

 time on a purely flesh diet, as they must eat so large a quantity of flesh that their digestive 

 organs cannot digest it. The herbivora cannot live upon flesh food, as their digestive appa- 

 ratus is adapted solely for the digestion of vegetable food. 



[The proteid metabolism depends (1) on the amount of proteids ingested, for 

 the great mass of these becomes changed into circulating albumin ; (2) upon the 

 previous condition of nutrition of the organism, for we know that a certain amount 

 of proteid may produce very different results in the same individual when he is in 

 good health, and when he has suffered from some exhausting disease. (3) The use 

 of other foods, e.g., fats and carbohydrates. If a certain amount of fat be added to 

 a diet of flesh, much less flesh is required, so that the N metabolism is reduced by 

 fat. This is spoken of as the " albumin-sparing action" of fats.] 



Exactly the same result occurs with other forms of proteids, as with flesh. It 

 has been proved that gelatin may to a certain extent replace proteids in the food, 

 in the proportion of 2 of gelatin to 1 of albumin. The carnivora, which can 



