8 



PRINCIPLES OF FEEDING FARM ANIMALS 



in the soil where the plant grew. The elements found in the mineral 

 matter are present in one or two forms : Either in inorganic form, 

 as sulfates, phosphates, nitrates, chlorides, or silicates, combined 

 with bases, like potassium, sodium, calcium, magnesium, and iron ; 

 or in organic form, as constituents of organic compounds. Espe- 

 cially in the case of seeds of plants the ash materials are present 

 largely in the latter form. 



Ordinary feeding stuffs contain, as a rule, only relatively small 

 amounts of mineral matter, viz. : Less than 5 per cent, except in 

 the case of some factory by-products and dry forage, in which the 

 ash content may go even above 10 per cent. Leafy plants contain 



ID 20 30 40 50 60 70 60 90 100 110 120 130 140 150 160 170 180 

 ALfALFA HAY 

 COTTON-5EED MEAL 

 CLOVER HAY 

 WHEAT BRAN 

 LINSEED MEAL 

 DRIED BEET PULP 

 TIMOTHY HAY 

 DRIED BREWERS' 

 OAT5 

 CORN 



GLUTEN FEED 

 POTATOES 



FIG. 2. Mineral matter in a ton of common feeds, in pounds. 



relatively large percentages of ash, like all parts of plants in which 

 a considerable evaporation of water takes place. On the other hand, 

 by-products in manufacturing processes where the raw materials 

 are treated with large quantities of water, as gluten feed, brewers' 

 grains, beet pulp, etc., have comparatively low ash contents (Fig. 2). 



Protein is a general name for nitrogenous organic compounds 

 of a very complex chemical structure. They contain carbon, oxygen, 

 hydrogen, and nitrogen, with a small percentage of sulfur and, in 

 some cases, phosphorus. The name protein was given to these sub- 

 stances by Mulder, a German chemist, and means the first or the 

 rnpst important. This term is justified from a physiological point 

 of view, inasmuch as protein is absolutely essential to animal life, 

 for the formation of muscle, body fluids and other nitrogenous body 

 substances, as well as for the continued exercise of vital functions. 



The protein substances are characterized by the fact that all 

 contain the element nitrogen, which is not found in the other groups 



