392 FUNDAMENTALS OF AGRICULTURE. 



place of fats and carbohydrates, but such substitution 

 is not practicable, as protein generally costs more than 

 fats and carbohydrates. Protein hardly ever performs 

 the functions of fats and carbohydrates unless these 

 latter compounds are lacking in the animal's food. 



Functions of Fats and Carbohydrates. These nu- 

 trients supply the fuel for the animal body. They fur- 

 nish the materials that keep the animal warm. The 

 fats and the carbohydrates also produce fat in the 

 animal body. The fats are not always changed in 

 forming fatty tissue, but the carbohydrates are trans- 

 formed into fats before being stored as such. As an 

 energy and heat producer fats have a greater value 

 than carbohydrates. Fats are considered as being 2.25 

 times more valuable than carbohydrates in this respect. 

 In other words, one pound of fat is worth 2.25 times 

 as much as one pound of carbohydrates for animal fuel. 



* Classification of the functions of the nutritive ele- 

 ments : 



{Supplies materials for the bones and framework of the 

 body. Helps build up the blood, tissues, digestive 

 fluids and secretions. 



f The flesh formers. Substances for the making of the lean 



Protein 4 meat, muscles, skin, ligaments, horn, hair and milk. 



[ Sometimes used as fuel to give warmth and energy. 



{Furnish fuel to keep the animal warm. Help to pro- 

 duce energy. Aid in the production of fatty tissue. 

 As a heat producer fats are 2.25 times as valuable as 

 carbohydrates. 



,f 



Supply the fuel to keep the animal warm and to pro- 

 duce energy. Are transfi 

 L production of fatty tissue. 



Do not make the pupils memorize the tables in this section, but 

 require them to understand the fundamental principles involved. 

 Take the class to some pasture or stable and have them look over 

 some animals. Make them feel the body warmth. Show them to 

 which parts of the animal the protein, fats, carbohydrates, water and 

 ash are distributed. 



* The idea and some of the data in this classification came from 

 Bulletin 106 of the North Carolina Experiment Station. 



