Atresia Ani* 



By A. T. Kinsley, M. Sc, D. V. S., Pathologist, 

 Kansas City Veterinary College 



This is the season that the veterinarian is 

 called to attend cases of parturition. Obstetrical 

 cases in addition to the general practice entails 

 the expenditure of considerable energy and the 

 practitioner may not be as careful and observing 

 in some cases as he should be. 



Atresia Ani is a malformation that is not rare 

 and is frequently not observed by the attending 

 obstetrician. This malformation is the result of 

 imperfect union of tissues. During the earlier 

 stages of development, i. e., the embryonic period, 

 the digestive tract from the pharynx to the rec- 

 tum inclusive is formed from the entodermal 

 tube. The anus is formed in the fetal stage by 

 invagination of the skin surface, the anus and 

 rectum are at this stage separated by a thin 

 membrane. Normally the rectal and anal walls 



*Seprinted from the MUaouri ValUy Veterinary Bulletin, June, 1908. 



