CHAPTER XVII. 

 THE BACILLUS OF SWINE ERYSIPELAS. 1 



Introduction. 



Section I. Experimental inoculation, p. 284. 

 Section II. Morphology and cultural characteristics, p. 284. 

 Section III. Biological properties, p. 286. 



Section IV. The detection, isolation and identification of the bacillus, p. 287. 

 The bacillus of mouse septicaemia (Bacterium murisepticum), p. 288. 



SWINE erysipelas (measles) is due to a bacillus discovered by Pasteur and 

 Thuillier, and of which the classical description was given by Loaffler. 



A very large number of deaths among swine are attributable to swine erysipelas 

 and the disease becomes therefore of considerable economic importance. The 

 acute form of the disease is nearly always fatal, and in infected herds about 50 per 

 cent, of the animals die. 



Swine are liable to the disease between the ages of 6 months and 2 years ; under 

 3 months old they are immune and beasts more than 2 years old are rarely infected. 



Highly bred swine, such as the English breeds, are the most susceptible, while 

 wild animals are immune. 



Swine become infected by feeding upon the excreta of infected animals ; they 

 are almost the only animals susceptible to the spontaneous disease ; pigeons, [mice], 

 and rabbits which have frequented infected pig- sties are however sometimes attacked. 



The flesh of suspected animals, and even of those dead of the disease, is frequently 

 consumed as food without apparently causing any harmful effects in man : but 

 cases of painful erythema have been noticed following the accidental inoculation 

 of the virus. 



Swine erysipelas occurs in two forms, acute and chronic. 



The acute form of the disease is characterized by the appearance of bright or 

 dark red purpuric spots on the skin, chiefly about the ears, the anus and vulva, the 

 internal surface of the thighs and the groins. The animal suffers from diarrhoea : 

 it grunts dismally and remains lying down hidden in its bedding with its tail uncurled 

 and hanging down : its temperature is raised and death takes place in from 48-72 

 hours. 



Chronic swine erysipelas is the less severe form of the disease ; recovery after an 

 attack is not infrequent, though some animals never recover completely. When 

 an animal begins to recover, desquamation occurs about the spots on the skin. The 

 characteristic swelling of the joints is responsible for a peculiar gait noticed in infected 

 animals, and for the disease being sometimes called Gout. 



Post mortem, in swine dead of the disease, there is frequently in addition to the 

 spots on the skin an intense congestion of the serous membranes and of the intestines ; 

 the lymphatic glands especially those of the abdomen are swollen and congested ; 

 the spleen is very much enlarged and diffluent and shows bosses on the surface ; 



1 [(Fr. Rouget du pore, erysipele, rougeole. Ger. Schwein Rothlauf.)J 



