PROGRESSIVE POULTRY CULTURE 113 



muscle, trains and nerves. These compounds also 

 form the collagen of the tendons, the ossein of the 

 skeleton and parts of the skin, feathers, 'beak, toe- 

 nails, etc. The white of the egg (albumen) is almost 

 pure protein. 



The proteids may aid in keeping up the body tem- 

 perature in case of necessity. 



These nitrogenous constituents are absolutely nec- 

 essary to the continued life or growth of the fowl. 



3. Carbohydrate Portion: A very large part of 

 some of the favorite foods of fowls consists of starch, 

 sugar and fiber made up chemically of carbon and the 

 elements of water (oxygen and hydrogen). This group 

 receives the name of carbohydrates. 



These nutrients, especially the digestible sugars and 

 starches are valuable and economical sources of heat 

 and energy and are also stored in the fowl's body in the 

 form of fat. 



4. Fatty Portion: Many foods contain fats or oila 

 which are also composed of cartoon, oxygen and hydro- 

 gen. These fatty constituents have on the average two 

 and one-fourth times the heating power of the carbo- 

 hydrates, when oxidized in the fowl's system to main- 

 tain body temperature. When more fatty nutrients are 

 digested and assimilated by the fowl than are needed 

 it usually proceeds to store up the surplus in the form 

 of fat A well-fed, caponized chicken may thus increase 

 in plumpness until one-third of its body weight is com- 

 posed of fat 



THE FEED-STUFFS. 



Fowls are omnivorous, eating nearly all things that 

 are eatable. 



Their food should be organic, i. e. of plant or ani- 

 mal origin. 



Whatever feed-stuffs are used have their nourish- 

 ing value determined by the digestible nutrients which 

 the fowls extract from- them in the process of digestion. 



The necessary supplies for the digestive system 



