442 DISEASE IN WILD MAMMALS AND BIRDS 
animal protein. No vitamine deficiency has so far been 
determined. Wilson's careful studies of the diets known 
to have produced the condition show that the etiological 
factor lies in a deficiency of the protein molecule. The 
results of Goldberger(30) corroborate this fact, and he 
concludes from his latest studies that '' the dominating 
role of diet in the prevention and causation of pellagra 
is referable primarily to the character of the protein sup- 
ply or to the specific quality of the aminoacid makeup 
of the protein supply. ' ' Just w^hat aminoacid or combina- 
tion of aminoacids it is, has not been determined, nor has 
the possibility of a vitamine alone or in combination with 
the aminoacid factor been absolutely excluded. 
The principal influence of the omnivorous diet is 
toward those degenerations arising primarily from im- 
balances in the inorganic makeup, or to insufficiencies of 
certain necessary factors. The vitamine deficiencies are 
markedly less prevalent in animals than in man whose 
food is less often consumed in its natural state. It is 
now known that much of the injury and loss of nutritive 
value in foods is produced by the processes involved in 
preparation, preservation, refinement and storage. 
Whenever the choice of food is not restricted, vitamine 
deficiencies do not occur. The vitamine requirements 
probably differ in different species and in individuals 
from the same species according to their environmental 
and individual variations. It is very possible that if the 
diet is low in vitamine content there may arise conditions 
of relative deficiencies ; and McCarrison has shown that 
a vitamine deficiency associated with a high fat or car- 
bohydrate content may disturb the balance of the endo- 
crine glands. It is how^ever to the inorganic content of 
the omnivorous food that most of the disturbances pecul- 
iar to this diet are to be assigned. 
With the flesh eating animals and birds the records 
present a very different picture. Disorders of the diges- 
(30) Jour. A.M.A., 1922, 79, 2132. 
