COMPOSITION OF FEED MATERIALS 213 



or bony framework and is composed largely of lime and phos- 

 phorus, the body of the average bird containing about 4 

 per cent of ash. It is especially desirable in the feed of a 

 young growing animal, since it is needed for the formation 

 of the skeleton. 



Water. — This is in the body in large quantities, the body 

 of the average bird containing more than 50 per cent. It is 

 diffused between and within the cells, and also permeates 

 the entire body structure. Water is composed of two chemi- 

 cal elements, hydrogen and oxygen, two parts of the former 

 being combined with one part of the latter to form the liquid. 

 The general composition of the bird's body varies with its 

 age, breed, and activity. The older it becomes, the bigger 

 the ash content, and the less the water and fat in its body; 

 this is especially true of male birds. The White Leghorn 

 breed, which is very active, develops considerable tough, 

 fibrous tissue and little of the tender, juicy flesh which is un- 

 excelled for eating. Hence, the more active the breed, the 

 tougher and more fibrous becomes the meat. 



COMPOSITION OF FEED MATERIALS 



Materials which are valuable for poultry feeding are 

 similar in composition to the constituents of the body which 

 they furnish. The same compounds found in the feeds 

 are present in the body. To this number a new one is added, 

 namely carbohydrates. In the following paragraphs we 

 will discuss the five compounds found in feeding stuffs, — 

 protein, carbohydrates, fat, ash, and water. 



Protein. — Common examples of protein feeds are meat 

 scraps, linseed meal, cottonseed meal, and other so-called 

 concentrated by-products. Protein in feeds is of the same 

 chemical composition as when found in animals (Fig. 122). 

 It is essentially a nitrogenous material, and is the determining 

 factor in poultry feeding for all purposes. In the feeding 

 of birds it has many uses, but it is essential for the formation 



