CATTLE PLAGUE. 147 



Now and then a relapse takes place after signs of improvement 

 have become estahlished, and in some instances animals appa- 

 rently quite convalescent commence to purge, and to sink from 

 intestinal and other complications. 



Mr. Gamgee says that the disease is periodical in its manifes- 

 tations : " Improvement in the morning ; exacerbations at night ; 

 a distinct subdivision of an attack into stages, and from the date 

 of the crisis either sudden aggravation or gradual abatement of 

 alarming symptoms." This periodicity may exist to some ex- 

 tent ; it is, however, so slight as to escape ordinary observation. 

 Indeed, in many instances I have observed that the symptoms 

 were quite as bad in the morning as in the evening. 



The mortality in Great Britain is always very great. Amongst 

 liussian cattle mild cases of the disease are not of uncommon 

 occurrence, the animals passing through the disease presenting 

 but slight symptoms of it. But even in Eussia from 80 to 90 

 per cent, is reckoned the usual mortality, and under the most 

 favourable circumstances 53 and 56 per cent, have been witnessed. 



Although the disease is so highly contagious, it is found that 

 some cattle resist its influence, remaining healthy wdiilst sur- 

 rounded with the plague ; but it is also no less remarkable that 

 an animal thus exposed to the contagium will, whilst resisting 

 the malady itself, convey the disease to other cattle, the morbid 

 material being lodged about its body. 



The ijost mortem appearances of cattle plague vary in different 

 stages. 



In the first stage there is congestion of the mucous membranes 

 of the mouth, larynx, pharynx, and particularly of the fourth 

 stomach near its pyloric end, the small intestines are marked 

 with streaks and patches of red, and the follicles are uniformly 

 reddened. 



The surface of the mucous membrane is covered with a viscid, 

 tenacious, and bloody secretion ; is denuded of its epithelium, 

 whilst the submucous tissue is charged wdth a turbid semi-fluid 

 exudate. The condition of the first two stomachs calls for no 

 special remarks. Sometimes the rumen presents patches of 

 congestion on its mucous surface, approaching in tint the 

 colour of port wine, and in a very small number of cases 

 sloughing of the membrane has been observed. 



The condition of the third stomach has been supposed to give 



