190 CLINICAL BACTERIOLOGY AND 



called "buttins" of swine fever. In acute conditions a 

 typical gastro-enteritis with petechial hasmorrhages may 

 be noted. 



In some cases necrosis of the mucosas over a large area 

 of the large bowels is pronounced, giving the surface a 

 dirty greyish-yellow appearance. 



The lymphatic glands are extensively involved, in- 

 filtrated, and often hasmorrhagic, and, later, patchy necrosis 

 is seen. 



On the pharyngeal mucosae hasmorrhagic patches with 

 ulceration and necrotic areas are noted, and the same con- 

 ditions may be seen in the larynx and the root of the 

 tongue. 



Where the pulmonary organs are involved, we find a 

 typical croupous pneumonia, and in advanced cases multiple 

 necrotic centres are distributed through the parenchyma 

 of the lungs. In addition, a typical pleurisy may be present, 

 which tends to become plastic, and sometimes pericarditis 

 is noticed. 



Sero-Therapy. 



It is obvious that so long as the bacterium of swine fever 

 remains undetected so long will it be impossible to make a 

 prophylactic or curative vaccine. To prevent or cure the 

 disease we must therefore fall back upon serum-therapy. 



As far back as the year 1897 Preisz obtained the blood 

 from a pig which had recovered from a natural attack of 

 swine fever. From this he made a serum, injecting 10 c.c. 

 each into thirty pigs, and produced a degree of immunity. 

 These thirty pigs were placed together with thirty healthy 

 pigs and with a few affected ones. Eighteen of the in- 

 oculated pigs sickened and nine died, while all of the 

 thirty control pigs died. 



Since that period great improvement in the technique 

 has taken place, and to-day on the Continent very great 

 value is placed upon the serum treatment for swine fever 

 both as a prophylactic and as a cure. 



