38 THE DISEASES OF THE DOG. 



In the differential diagnosis of rabies a number of 

 popular errors as regards the disease have to be avoided. 

 Thus extensive frothing from the mouth, fear of water, 

 constant firm compression of the tail between the hind 

 legs are not seen in this disease so invariably as to 

 make them pathognomonic. Also the presence of ranula, 

 or cysts beneath the tongue, which used to be insisted 

 on, is not to be relied on. It has been supposed that 

 bitches never turn mad spontaneously, but then we do 

 not know that dogs do so either ; certain it is that 

 spaying as a preventive of rabies is a fallacy, although 

 it seems to be rather extensively resorted to in France. 

 That dogs which have been " wormed " do not go mad, 

 and that removal of the tip of an animal's tail, taking care 

 that one of the tendons of the depressors is drawn out and 

 shall curl up like a worm in elastic recoil when broken, 

 are ideas based on ignorance but not yet obsolete. The 

 occasional occurrence of a pustular discharge from the 

 nose and eyes with corneal ulceration in rabies have some- 

 times led to confusion of this disease with distemper, yet 

 the differences between the two disorders are so marked 

 as to render such a mistake possible only with very care- 

 less diagnosis. Pits due to epilepsy, especially those 

 which follow distemper, differ altogether from symptoms 

 shown in rabies. The rabid dog does not lose conscious- 

 ness, he does not lie on the ground struggling and champ- 

 ing the jaws and foaming at the mouth as an epileptic 

 does ; the latter may on " coming to " bite anyone holding 

 him and rush off, but his escape is very different from the 

 way in which the mad dog "runs a muck." Youatt 

 speaks of cases where dogs have been bitten on the ear 

 and the disease thus conveyed been mistaken for canker 

 of the ear ; in each the irritable part will be energetically 

 scratched, but in rabies some of the earlier symptoms of 

 general disorder will be present at this stage, and there 

 will be no such local eruptions as are found in ear canker ; 

 tetanus, colic, and (as we have already seen) bone in the 

 throat have been confused in diagnosis with rabies. Such 

 errors can occur only with imperfect examination of the 



