236 POULTRY BREEDING AND MANAGEMENT 



grind the food. The tough muscular walls of the gizzard 

 aided by the grit that the hen picks up takes the place of 

 teeth which in domestic animals grind the food. The 

 moistened ground grain passes from the gizzard into the 

 large intestine, or duodenum, where it is acted upon by 

 the pancreatic juices. The bile from the liver also enters 

 the duodenum and aids in the digestion of the fats of the 

 food. The digestive process is here completed and the di- 

 gested portions of the food are absorbed into the blood and 

 the waste or indigestible portions forced on to the cloaca. 

 The ceca correspond to the appendix in man, and their 

 function is not understood. The total length of the diges- 

 tive canal from beak to vent is 4 to 5 feet. 



The digestive process of the fowl works with extreme 

 rapidity. Investigations have shown that in about two 

 days after eating, the food has entered into the making of 

 the egg yolk. In two days after being eaten certain foods 

 have given a color to the outer layers of egg yolk. 



To keep this complex system of digestion in proper work- 

 ing order requires a variety of good food, abundant exer- 

 cise, and fresh air in the house. 



What Foods Should be Fed. The table of composition 

 of foods contains the names of foods that are used for poul- 

 try. This table does not, however, exhaust the list, as there 

 are doubtless other foods that are used to a limited extent in 

 different localities. The composition of any food not on 

 this list may usually be obtained from the experiment 

 stations. 



