Circular No. 50. March, 1915. 



MASSACHUSETTS AGRICULTURAL EXPERIMENT STATION, 



AMHERST. 



RATIONS FOR DAIRY STOCK* 



By J. B. LiNDSEY. 

 1. Composition of Cattle Feeds. 



All cattle feeds, whether in the form of grains and their by-products, 

 or as hay, corn silage and straw, are composed of the following groups 

 of substances: 



Water — The several grains and their by-products contain from 7 to 

 12 per cent of water; hay and straw, 12 to 16 per cent; field-cured corn 

 stover, 30 to 40 per cent; and corn silage, 76 to 80 per cent. 



Ash represents the mineral ingredients, and constitutes the ashes after 

 the feed is burned. These ashes consist of lime, potash, soda, mag- 

 nesia, iron, phosphoric and sulfuric acids. 



Protein is a collective name for all of the nitrogenous matter; it cor- 

 responds to the lean meat in the animal, and may be termed "vegeta- 

 ble meat." It has the same elementary composition as animal flesh. 

 When fed to animals as a component of the various feed stuffs, it serves 

 as the exclusive source of flesh as well as a source of heat or energy 

 and fat. 



Crude fiber or cellulose is the coarse or woody part of the plant. It 

 may be called the plant's framework. It is a source of heat or energy 

 and fat. 



Non-nitrogenous extract matter represents the sugars, starch and 

 gums. It is the principal source of heat or energy and animal fat. 



Fat includes not only the various oils and fats in all grains and coarse 

 fodders, but also waxes, resins and coloring matters. It is frequently 

 termed ether extract, because it is that portion of the plant soluble in 

 ether. It serves as a source of heat or energy and fat in the body of 

 the animal. 



Carbohydrates is a term which is generally used to include both the 

 fiber and the non-nitrogenous extract matter. 



It will thus be seen that all of the several groups of nutrients — pro- 

 tein, carbohydrates and fat — are sources of energy; that is, they furnish 

 the food or fuel to maintain the life of the body. They also are con- 

 vertible into fat. The protein, however (including the ash), is the only 

 group from which the animal can make its flesh or lean meat. In or- 

 der to form the bones all the groups are used. 



* Originally prepared for the Massachusetts State Board of Agriculture as Circular No. 3. 



