CORN AND ITS BY-PRODUCTS 



185 



usually available are oyster shells, limestone grit, and dry ground 

 bone. Their composition is shown in Table VI. 



TABLE VI. Composition of Sources of Lime (pounds in 100). 



Phosphate. Less than four per cent of the body of the adult 

 bird is mineral matter, consisting almost entirely of phosphate 

 of lime, and the use of phosphate has been found to be especially 

 profitable and practical in rations for growing chicks. Bone ash is 

 supplied in the form of granulated bone, bone meal, or cut bone. 



Organic Feeds. The feeds grouped under this heading are: 

 .(1) Grains and their by-products, which are termed concentrated 

 feeds, and (2) grasses, hay, and straw, which are called roughage. 

 Concentrates take their name from the fact that high nutrient 

 content is represented in small bulk; and roughage from the fact 

 that a larger amount of fibre or cellulose is present, and a larger 

 bulk represents only a small nutrient content. 



The leading grains must be relied upon mainly for poultry. 

 The different organic feeds naturally group themselves into the 

 following divisions: Grains and their by-products, animal feeds, 

 hays, grasses, and vegetables. As the by-products are closely 

 associated with the grains from which they are derived, these two 

 groups will be discussed together. 



Corn and its by-products are the principal sources of feed for 

 poultry, the great value of this grain lying in its available energy, 

 due to its high percentage of easily digested carbohydrates and 

 fat and the absence of all poisonous substances. 



When birds have access to a variety of grains, they usually 

 select the corn first, showing that it is extremely palatable. There 

 is very little difference in analysis between yellow and white corn. 

 The yellow corn, however, is preferred where it can be secured, 

 as it has a tendency to impart its color to the flesh of the birds 

 feeding on it, and also colors the egg yolk* a deeper yellow. It is 

 a better practice to feed cracked rather than whole corn, as it 

 necessitates more exercise to secure a sufficient amount for one 

 meal. The composition of the two is the same, except that in 



