242 AGRICULTURE 



cut or crushed. Some seeds, such as corn, that have hard shells 

 have their food value increased by grinding. 



Scientists inade laboratory tests to learn the chemical value of 

 foods, and feeding tests to learn their digestible value. They 

 weighed and analyzed the food, products, and manure of animals 

 to learn how much food was digested. Experiments long and 

 carefully conducted enabled them to prepare tables showing the 

 feeding values of different foods and fodders, that is, their 

 amount of digestible protein, fat, carbohydrates, and ash. A table 

 containing a statement of some of these results will be found on 

 page 309. 



Every farmer bears practical testimony to the truth of these tests 

 by the different prices he sets on different feeds and fodders, and 

 the way he feeds and buys and sells. As a rule, the richer a food 

 is in nitrogen the greater its value. 



Feeding Standards. Scientists made feeding tests also to learn 

 the amount of digestible protein, fat, and carbohydrates that are 

 best for domestic animals under average conditions. They 

 studied the results of different foods and different amounts on 

 thousands of animals. The results are embodied in what are called 

 'feeding standards' (see page 309). These tell the proper ration, 

 or one day's food, for an animal of a certain weight under ordinary 

 conditions. 



A ration conforming to this standard and giving the proper 

 amount of digestible protein, fat, and carbohydrates is called a 

 'balanced ration.' Feeding standards are not hard-and-fast rules, 

 for there are differences among individuals, but they are good 

 general guides. 



As you have learned, food has a twofold value, its feeding value 

 and its manurial value. This latter subject has been discussed in 

 the chapter on Soil Improvement. 



