C0NTAQ10U3 DISEASES OF DOMESTICATED ANIMALS. 365 



INVESTIGATION OF SWINE PLAGUE. 



INTRODUCTORY. 



In the further investigation of swine plague Dr. Detmers finds but 

 few additional symptoms worthy of mention. As his observations ex- 

 tended through the winter he was enabled to observe the disease closely 

 during those months when it is neither so general nor so fatal as during 

 other seasons of the year. During the winter months, therefore, and in 

 the early S})riug, he found bleeding from the nose and symptoms of re- 

 spiratory disorders quite frequent, but there se«mcd to be fewer indica- 

 tions of gastric disorders than he had observed during the summer and 

 tall montlis. Neither was the prognosis, as a rule, so hopeless in the 

 winter and spring as during the summer and early autumn. This he 

 regards as attributable to the fact that during the former seasons the 

 seat of the jnorbid process is limited more frequently to the respiratory 

 organs and to the pulmonal tissue, and is not found so often in the in- 

 testinal canal. Thirty additional 'post-mortem examinations failed to 

 reveal any new morbid changes worthy of sj)ecial mention. A few 

 variations, and in some cases an unusual combination of morbid changes, 

 were observed, which will be found accuiately described in the text of 

 Dr. Detmers' report. The absence of worms or entozoa in 75 per cent, 

 of the whole number of animals dissected prior to December 1, and their 

 entire absence in every animal examined between that date and the 15th 

 of the same month, would seem to prove conclusively, Dr. Detmers 

 thinks, tliat the Kiorbid changes characteristic of swine plague cannot 

 be attributed to the work of entozoa. He thinks, however, that the 

 presence of worms in large numbers, occurring in weak, poorly-kept, 

 and neglected animals, may cause considerable mischief, aiid sometimes 

 occasion death, but in such cases the cause should not be attributed to 

 swine plague. 



Former experiments seemed to fully demonstrate the fact that swine 

 plague is an infectious and coiitiigions malady, and that it is easily 

 communicable from one animal to another by means of direct inocula- 

 tion, and by tlie introduction into the digestive organs of the infectious 

 principle l>y means of food and drinking water; second, that an exceed- 

 ingly small quantity of the virus or infectious ])rinciple is sufficient to 

 ])roduce the disease; third, that the period of incubation does not exceed 

 lifteen days, and lasts on an average from six to seven days; fourth, 

 that the small microphytes [hacilli) found in all the morbid products, in 

 the blood and other fluids, and in all excretions of the animals, would 

 seem to constitute the infectious principle of the malady. This being 

 the case Dr. Detmers instituted a series of experiments m order to de- 

 termine, if possible, first, whether the infectious principle consists solely 

 in the bacilli and their germs; second, whether an animal that has re- 

 covered from the disease has gained immunity from, a second attack; 

 and, third, whether the affection can be transmitted to other classes of 

 domesticated animals. The result of these experiments proved, first, 

 that an inocukition with haciUi and baoilkis-germs cultivated in so in- 

 nocent a fluid asmilk will produce the disease with just as much cer- 

 tainty as an inoculation with pulmonal exudation from a diseased or 

 dead hog ; second, that an animal that has been afflicted with the i>]iigue 



