AMERICAN POULTRY CULTURE 
because no other food can fill its position. Foods 
rich in protein are called nitrogenous foods. 
Those elements of a food which go to make fat, 
heat and energy are the carbohydrates. These are 
burned in the body, and any surplus above what is 
necessary to supply heat is stored up in the body as 
fat, to be drawn upon later should insufficient car- 
bohydrates or carbonaceous food be supplied. 
Ash is the mineral portion of feeding stuffs, and 
goes largely to make bones, egg shells, etc. Less 
of this material is needed than of the other two, 
and in making up a ration little attention need be 
paid to it, for most feeds contain a sufficient 
amount without any special provision being made. 
A “balanced”’ ration is one in which protein 
and carbohydrates are combined in such propor- 
Balanced tion that they will fully supply the 
Rations needs of the fowls but at the same 
time there will be no surplus of either. A 
“wide” ration is one which contains too large a 
proportion of carbohydrates; its continued use 
will cause the fowls to become too fat. A 
“narrow” ration is one too rich in protein; its 
continued use will affect the kidneys and liver, be- 
cause they will have been overtaxed in endeavoring 
to dissipate the excessive amount of nitrogen. To 
be sure, the over-supply of protein will, to a cer- 
tain extent, take the place of the carbohydrates 
that are lacking, but this should not be allowed to 
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