30 INTERNAL ORGANS OF FOWLS 



food passes through the upper part of the esophagus 

 a into the crop &; from the crop the food passes through 

 the lower part of the esophagus into the gizzard c; 

 and from there through the other organs of the digestive 

 system. 



Crop. In fowls and other granivorous, or grain-eating, 

 birds, the crop is relatively larger than the crop of 

 birds that feed largely on grass. Within the crops are 

 juices that moisten the food and hasten its passage into 

 the gizzard. 



Gizzard. The gizzard c may be looked on as a power- 

 ful grinding machine in which the whole grain and 

 other foods of poultry are ground, oftentimes finer 

 than they would be ground by the teeth of chewing 

 animals. The grinding is accomplished by means of 

 the powerful muscles of the gizzard, which keep the 

 mixture of sand, grit, and food within it constantly in 

 motion. In the gizzard the food is also acted on by 

 digestive juices before being passed into the intestines. 



Intestines. The intestines as applied to fowls means 

 all of the alimentary canal beyond the gizzard. The 

 intestines of the fowls, although different in many 

 respects from those of other animals, present a somewhat 

 similar appearance and have functions nearly identical 

 with those of the other domestic animals. In fowls, the 

 intestines are made up of the duodenum, and the rest 

 of the small intestines d, the caeca e, and the large 

 intestines and the rectum g. Inside of the intestines the 

 food is acted on by various digestive fluids, and 

 digestible nutrients within the food are taken from it 

 and eventually converted into blood. The inner walls 

 of the intestines are covered with minute projections 

 known as villi, which absorb the digested material 

 from the contents of the intestines. The indigestible 

 part of the food passes into the rectum g and out of 

 the body through the vent h. 



Liver. The liver i is a large, two-lobed organ of 

 peculiar cellular structure. It has two offices, one of 

 them being to purify the digested material brought to 



