LESSON LII 

 FOOD OF FARM ANIMALS 



Food necessary for growth. Besides air and water, 

 all animals, as well as plants, must have food in order 

 to live and grow ; and the feeding of animals is a large 

 part of the fanner's work. 



A food is any substance that can be eaten and used 

 in the body to produce growth and energy. Every 

 animal is provided with automatic indicators of its 

 needs. If it is thirsty, the body needs water ; and if it 

 is hungry, the body needs food. The natural appetite 

 tells also what kind of food the body needs. Dif- 

 ferent kinds of animals require different kinds of food. 

 For example, a horse gets hungry for oats and hay, 

 while such things would not taste good to a dog, be- 

 cause the dog requires meat. Most animals need a 

 variety of foods. A man would starve if fed on bread 

 alone, because it does not contain everything he needs. 



Materials in food. In addition to water, there are 

 four kinds of materials in food ; and all animals need 

 these materials in the right proportions. These ma- 

 terials are minerals, proteins, carbohydrates, and fats. 

 The minerals, with the exception of salt, are usually 

 present in sufficient quantities in the natural foods. 



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