44 



Diseases of Poultry 



I 



a 



the left side of a hen 

 carried out in such a way 

 as to show the principal 

 organs. Beginning at the 

 anterior end we see, when 

 the skin is removed from 

 the bird, two tubes lying 

 along the ventral aspect 

 of the neck. These are 

 the esophagus (1) and the 

 windpipe or trachea (2). 

 In the region where the 

 neck joins the trunk 

 there is a sac-like dilata- 

 tion of the esophagus, 

 the crop (3). 



Proceeding backwards 

 from the crop the ali- 

 mentary tube passes 

 through the thoracic 

 cavity and as it enters 

 the abdominal cavity 

 widens out into the pro- 

 ventriculiAs (4), or glan- 

 dular stomach. This 

 opens directly into the 

 gizzard (5) in which the 

 mechanical breaking up 

 and grinding of the food 

 material is carried on. 



After leaving the giz- 

 zard the food passes into 

 the intestine. The first 

 portion of the intestine, 



