1064 Veterinary Obstetrics 



tween it and the end of the gut becomes more and more attenu- 

 ated, until finally it disappears and the gut opens posteriorly as 

 the anus. In some cases the attenuation and disappearance of 

 the walls of the proctodeal pit fail to occur, and as a result the 

 young animal is born with an imperforate anus. 



In other cases, not only is there an arrest of the development 

 in this part, but the entire posterior gut, or any portion of it, may 

 fail to form or may become obliterated early, so that there is an 

 absence of both the anus and the rectum. 



The diagnosis of imperforate anus is comparatively simple, 

 since it depends upon the absence of that organ. Upon examin- 

 ation no posterior opening of the gut is discoverable. If only 

 the anus fails, the meconium may be pushed back against the 

 thin membrane, to form a tumor in the anal region ; while, if the 

 rectum itself is absent, no such tumor occurs. 



The handling of imperforate anus consists of making an in- 

 cision through the skin of the part, down upon the accumulated 

 meconium. If the rectum is absent, so that the accumulation of 

 meconium in the anal region does not occur, the animal should 

 be destroyed as valueless. 



In some instances in new-born females, there occurs an imper- 

 forate anus, accompanied by an imperfect vulvo-anal partition, 

 and the feces drop downward into the vulva through the defect- 

 ive partition, and escape therefrom involuntarily. Such a case is 

 illustrated in Fig. 42 on page 310. It may possibly be overcome 

 by inserting the finger or a curved sound through the vulva up 

 into the anus, and, directing it backward, cutting down in the 

 anal region until the wall is perforated. The communication 

 between the anus and vulva may then be denuded of its raucous 

 membrane, and closed by sutures. However, because of the 

 difficulty of bringing about the closure of an opening in this 

 place, it would be better as a rule to destroy the young animal, 

 unless it is of unusual value for work purposes. An animal with 

 such a defect should not be used for breeding. 



4. Imperforate Vulva. 



Imperforate vulva is fundamentally referable to the same cause 

 as we have already described as operating in imperforate anus. 

 The vulva is formed in the same manner as the anus, that is, it 

 originates from the lower portion of the proctodeal pit. The 



