Comparative Nutrition of Man and Domestic Animals: Volume I

The science of nutrition deals primarily with the interactions between the animal body and its food supply with the ultimate purpose of defining quantitatively the fully adequate food supply for any combination of animal functions and for any type of internal and external stress. Obviously, this purpose can best be realized most economically, not by studying all possible combinations of animal functions, but, in so far as possible, by studying animal functions each in turn with reference to the nutrient expenditures or storages involved—in growth, activity, reproduction, lactation, etc.—and the conditions, within the animal or in the environment, that modify these methods of nutrient disposal. In this way, nutrient requirements can be assessed for each function under any given set of conditions.