238 AGRICULTURE 



The kind and quantity of food given animals is a matter of so 

 much importance that there is a saying that 'feed makes breed.' 



We have learned something about crop feeding ; let us now con- 

 sider the subject of stock feeding. 



Soil and Plant. You have already learned that processes in 

 the soil prepare elements for plant use, changing unavailable ones 

 into available forms. Then the plant changes these inorganic 

 elements, gases and minerals, into organic structure, corn, 

 clover, cotton, according to its nature. 



Plant and Animal. The plant changes substances into protein 

 or compounds containing nitrogen, into fat or oils, and into starchy 

 and sugary compounds called car bo hy'drates. In addition 

 to these, the plant contains water and ash or mineral matter. The 

 animal body is made up of similar substances, for all of which, 

 except water, animals are dependent on food furnished directly or 

 indirectly by plants. 



As the soil processes prepare elements for the plant, so the plant 

 prepares them for the animal. Corn and clover, hay and grain, 

 are changed by the animal into blood, flesh, and bone. 



Food Assimilation. The process begins in the mouth. There 

 the food is chewed and mixed with saliva. It passes through the 

 stomach and the intestines, where it is subjected to the action of 

 various juices; food thus acted on is said to be 'digested.' This 

 digested food passes through tiny tubes, called lac'te als, into the 

 blood vessels. As the sap carries nourishment to the plant, the 

 blood carries nourishment to the animal and in a wonderful way 

 not clearly understood by us makes flesh and bone. The un- 

 digested part of the food passes from the system through the kidneys 

 and bowels. 



Uses of Food. Let us consider the uses of food to animals. 



First : Food supplies material to repair the waste of the system^ 



