306 



POULTRY PRODUCTION 



nutrient. All poultry feedstuffs are composed of one or 

 more of the following groups of nutrients: (1) water, (2) 

 ash, (3) proteins, (4) carbohydrates, and (5) fats. For con- 

 venience, these nutrients may be classed as follows: 



Dry matter 



Water (1) 

 (1) Ash (2) 



(2) Organic nutrients 



Inorganic nutrients 



(1) Proteins ' 



1(1) Crude fiber 

 (2) Nitrogen- 

 free extract 

 (3) Fats 



Of these, water alone is a definite chemical compound. 

 Ash, protein, carbohydrate, and fats, which collectively 

 form the dry matter, are classes or groups of compounds 

 having certain distinctive characteristics. 



Relation of the Nutrients to Production. — Both the fowl's 

 body and the egg are composed of the same five groups of 

 compounds. These compounds are not in most cases trans- 

 ferred directly as such from the feed to the tissues, but are 

 split up in the digestive tract and remade. 



There is, however, a close relation between the nutrient 

 composition of the feed and its use in building tissue. The 

 ash in the body or in the egg can only come from the ash in 

 the feed. The protein of the body can be built up and the 

 protein of the egg elaborated only when protein is furnished 

 in the feed. While, as is shown elsewhere, fat may be manu- 

 factured from protein it is normally made over from fats in 

 the feed or built up from carbohydrate in the same source. 

 The very small amount of carbohydrate in the fowl's body 

 and the still smaller amount in the egg have the carbohydrate 

 of the feed as their original source. 



Water. — ^Water plays a highly important part in the pro- 

 cesses which collectively result in production. (1) It serves 

 to soften the feed in the crop, preparing it for maceration 

 in the gizzard. (2) It is a constituent part of the body of the 

 fowl and of the contents of the egg, comprising over 55 per 



