DISEASES OF SWINE AND OTHER ANIMALS. 55 



tious principle has beeu iutrodncfid into Mr. Locke's pasture hy the car-loads of dis- 

 eased swine which pass by every evening, and which sometimes remain standing on 

 the tracks, at a distance of not uiuch over forty rods from the hog-pasture, for half an 

 hour or longer; whether the vicinity of the rendering establishment has been instru- 

 mental in bringing about an infection ; or whether the infectious priucii)lo has been 

 communicated l)y other means, I have not been able to ascertain. 



The herds of Mr. Clellaud (or McClelland), nine or ten miles northwest of Champaign, 

 and of Mr. Allen, six or seven miles northeast of Urbana, have remained exempt for a 

 long time, proliably because neither of them has any close neighbors, hut finally the 

 disease, spreading from farm to farm, has reached their herds. 



Mr. Clay West, three and a half miles northwest from Champaign, living also some- 

 what isolated, expected that his swine (forty-seven head) would remain exempted. 

 Most of them (forty-two or forty-three) obtained their water for drinking from a run- 

 ning streamlet which, three-fomths of a mile above, passes through the hog-pasture 

 of another fann. On the latter swine-plague made its appearance, and three weeks 

 later Mr. West's swine commenced to die. So it must he supposed that the infection 

 had been brought about bj" the water in the streamlet. Mr. West, as soon as he 

 found that his hogs commenced to die, sold twenty-seven head to he shii)ped to Chi- 

 cago. 



3. MORBID CHAXGES AFTER DEATH. 



Since November 15th I have made some more post-mortem examinaiions, mostly for 

 the purpose of obtaining material for microscopical investigation; but have found 

 nothing not found before, or of any sj>ecial imi^ortance, except in one case, of which, 

 therefore, a full account may not be superfluous. It was a pig of Mr. Clellan's (or 

 McClelland's), who had lost four head out of seventeen witMn a few days, or after 

 brief sickness. The pig iir question, which was a little over four months old, had been 

 sick only two or three days. The post-mortem examination was made on November 

 22d, about sixteen hours after the animal had died. 



Externalhj. — Considerable capillary redness of a purple htfe in the skin on the lower 

 surface of the body, between the legs, and behind the ears. Internallij. — Lower and 

 anterior jjarts of both lobes of the lungs hepatized (red hepatization) ; the rest of both 

 lobes gorged with blood-serum or fluid exudation ; j)ericardimn coated with plastic exu- 

 dation ; auricles of the heart congested, the capillary vessels tinged with dark-colored 

 blood ; lymphatic glands, but especially those of the mesenterium, very much swelled ; 

 liver, sclerotic ; serous membraneofsomeof the intestines(csecumandcolon)coated with 

 exudation; ecchymoses and capillary redness in pyloric jjortiou of the stomach ; and 

 a few worms (Trichocepliahis crenatus)mcaicxiva, but no morbid growths or ulcerous 

 tumors whatever in any part of the digestive canal. This case is worth mentioning, 

 because no morbid growths or ulcerous titmors were found in the coecmn and colon, 

 or in other parts of the intestinal canal ; it consequently shows once more that em- 

 bolism and subsequent exudation in the lungs and in other tissues are more constant 

 and more characteristic of the morbid iirocess of swine-plague than the iieculiar morbid 

 growths or ulcerous tumors in the ca;cum and colon. 



Whether those ulcerous tumors on the intestinal mucous meml^rano occur only in 

 cases in which the infectious principle has been introduced partly or wholly through 

 the digestive canal, and are absent in those cases in which the haciUi and their germs 

 have entered exclusively through wounds or lesions, or whether, finally, this presence 

 or absence depends upon other influences and conditions, is a question which I am 

 not fully prepared to answer. It has decidedly the appearance that the seat and the 

 character of the morbid changes depend, to a certain extent at least, upon the means 

 and parts by and through which the hacilU and their germs have entered the animal 

 organism. 



My opinion, expressed in my report of the 15th ultimo, that an infection is brought 

 about either through the digestive canal or through wounds or lesions, and probably 

 not through the respiratory mucous membi'ano and through the skin, if no wounds 

 or lesions are existing, has been corroborated by an observation made at Mr. West's 

 place. I was there on November 20th. The disease had made its appearance on Novem- 

 ber 10th. Mr. West had lost five animals, had sold twenty-seven more or less diseased, 

 and still had fourteen or fifteen, including four or five older hogs kept in a separate 

 pen, about 12 by 16, which had a wooden floor, and was separated from the hog-lot or 

 hog-pasture only by a board fence. Those older animals receive and have received 

 their water for drinking from a well, while all those kc])t in the hog-lot or hog-iiasture, 

 origin.'illy forty-two in number, had access to the streamlet before mentioned. None 

 of the older animals, although breathing the same atmosphere as the rest, showed any 

 symptoms of disease, and are still healthy (November 29th), as far as I have been able 

 to learn. 



In conclusion, I may say that swine-plague does not seem to bo commniucable to 

 any other domesticated animals, and must be considered as a disease sui generis pe- 

 culiar to swine. 



