A GUIDE FOR KEEPERS OF POULTRY 281 
have an injurious effect upon the color or flavor of the 
product. The age of the fowl, the breed, the kind of 
product which it is desired to produce, must be taken 
into consideration; as to whether the feed is intended to 
grow bone and muscle or to produce eggs or to fatten. 
It pays to give such points close attention. 
“The ration must provide the two classes of feed nutri- 
ents, the protein and carbohydrates, in such proportions 
that they will supply the daily need of the fowl’s system. 
It must also provide sufficient digestible protein to sup- 
ply the waste of tissue with new growth, and to produce 
eggs. It must provide sufficient carbohydrates to furnish 
heat, energy and to lay by a little surplus fuel in the form 
of fat. It is not how much a fowl eats, but how much it 
can digest, that determines the value of feed. Various 
classes of animals differ in their capacity to digest the 
same kinds of feeds. Feeds also vary in their digestibility 
when used by the same animal. Unfortunately, the pro- 
portions of each poultry feed which fowls can digest 
ordinarily have not as yet been determined. Therefore 
we are obliged to accept standards of digestibility which 
are used in formulating rations for other animals as the 
result of many experiments.” 
The principles laid down by Prof. Rice contain every- 
thing that it is necessary we should keep in mind when 
formulating a ration for fowls. As he remarks, we have 
no such authoritative feeding tables as have feeders of 
other classes of stock. Investigators have never made 
the careful experiments with poultry that Wolff and 
others have with horses, cattle, sheep and swine. The 
best and about the only work of this kind that has been 
done in this country was by Wheeler at the New York 
station. He found that about 500 pounds live weight of 
