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, 

 in combinations of two or more of the elements, as sulfates, phos- 

 phates, nitrates, chlorides, or silicates, combined with bases, as 

 potassium, sodium, calcium, magnesium, and iron; or in organic 

 form, as constituents of organic compounds. Especially 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 con- 



10 20 30 40 50 60 70 60 90 100 110 120 130 140 150 160 170 180 



ALFALFA HAY 

 COTTON-SEED MEAL 

 CLOVER HAY 

 WHEAT BRAN 

 LINSEED MEAL 

 DRIED BEET PULP 

 TIMOTHY HAY 

 DRIED BREWERS' 

 OATS" 

 CORN 



GLUTEN FEED 

 POTATOES 



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



tain 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, etc., have comparatively small 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 

 most important. This term is justified from a physiological point 

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



The protein substances are characterized by the fact that all 

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



