714 INFECTIOUS DISEASES. 



But the inquiries made did not corroborate or favour the suggestion 

 that the disease which produced these morbid growths was in any way 

 infectious or contagious. Such inquiries as could be made led to the 

 opposite conclusion, since in every instance where the cases could be 

 followed up it was ascertained that the deaths had been quite sudden, 

 were limited to a single animal, and that those in contact remained 

 in perfect health. 



At this stage the all -important point to determine was whether 

 the disease which existed in this country, "verrucous endocarditis," 

 was communicable from pig to pig, and with this object numerous 

 experiments have been conducted to discover whether the bacilli found 

 within the hearts of diseased pigs were pathogenic to healthy swine. 



A large number of healthy pigs have been fed or inoculated with 

 the blood, the diseased portions taken from the valves of the heart, 

 and with artificial cultures of the bacilli obtained from the heart, 

 but in no instance has the attempt to produce this disease been 

 successful. 



PNEUMONIA OF THE PIG. 



The occasional association of pneumonia with or without pleurisy 

 in cases of swine fever has led many veterinarians in England to 

 regard lung complications as one of the lesions produced by that 

 disease. 



In the Board of Agriculture's report for the year 1894 a description 

 was given of the various diseases in the lungs of swine which had 

 come under notice, and it was therein stated that the Board had 

 been unable to discover any special lesion of the lung which would 

 warrant them in stating that it was indicative of swine fever or due 

 to contagion. 



It is an indisputable fact that pigs are extremely liable to pneumonia 

 and pleurisy. But as the clinical appearances present in the lungs 

 examined in no wise differed from those which take place in the lungs 

 of other animals which have been exposed to cold or septicaemia and 

 other causes, the Board's officers have never accepted these lesions as 

 being specific. 



It is well known that both in Germany and the United States out- 

 breaks of pneumonia of a contagious nature attributed to the presence 

 of a bacillus pathogenic to the pigs of those countries are reported to 

 occur. Indeed, contagious pneumonia of swine under the names of 

 schweinesuche in Germany and swine plague in America are regarded 

 as one and the same disease. 



In view of the fact that in a large number of cases pneumonia, 

 more or less extensive, sometimes associated with pleurisy, was found 



