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Reading-Course for Farmers. 



foods depends largely on the amount of crude fibre, which is the least 

 valuable of the four constituents because it is largely indigestible. 

 Young plants contain less crude fibre than plants that have matured 

 and formed seed, and hence are mere digestible. Nitrogen-free extract 

 consists of starch, sugar, gum, and the like. This substance forms 

 the largest part of most foods. This constituent is easily digested, 

 more so than any of the other three constituents, and hence foods rich 

 in nitrogen-free extract are ordinarily considered readily digestible. 

 Fat includes food constituents that may be readily dissolved in ether. 



Fig. 24. — All all-around serviceable family road pair. Suitable also for light 



farm work 



and is often called " ether extract." Fats are not so readily digested 

 as nitrogen-free extract. The functions of the fibre, nitrogen-free 

 extract and fat are all about the same: they go largely to form animal 

 fat and to produce heat. 



Protein. — Since protein alone contains nitrogen and since nitrogen 

 is essential to the formation of bones, muscles, blood, nerves, hair, 

 and hoof, it is necessary that we make ample provision for this food 



