DISEASES OF SWINE AXD OflTEK ANIMALS. 39 



C shows plain symptoms of disease; its appetite is poor, aiul some 

 emaciation lias gradually taken place ; at least C lias not improved like 

 A, and weighs about half as nnich as the latter, notwithstanding A is 

 in an open pen, exposed to the inclemencies of the weather, and C in a 

 good, new building, with a shingled roof, in which it is amply protected 

 against the changes of the weather. 



October YL — Pig C rather poor appetite; breathing a little accelerated, 

 and coat of hair somewhat rough and staring. 



October 18. — Pig exhibits plain sjTiiptoms of swine-plague; its 

 breathing is accelerated; it sneezes a good deal, and its appetite is poor. 

 Eats some in the evening. 



October 10. — Pig C improving; has better appetite. 



October 20. — Pig C much improved ; eats its Ibod again, but is not 

 greedy. 



October 21. — ISTo change. 



October 22. — Pig C is lively again, and eats well — at any rate, seems 

 to care more for its food. The sores on the ears are healing and disap- 

 Ijearing. 



October 23.— Pig C nuist be considered as fully recovered from its 

 slight attack. 



Up to date pig C has presented the appearance of a perfectly healthy 

 pig. Its ears have healed, and are now (November 11th) perfectly smooth. 

 It is lively and greedy for its food, but has grown very little, and weighs 

 to-day about half as much as pig A. It can be seen very plainly that 

 pig C has been sick. When I received A, B, and C, A was slightly the 

 best pig. B came next, and C was the smallest, but the diiference was 

 only a trifling one. 



The experiments just related show that the bacilU and their germs 

 must have a causal connection with the morbid process of swine-i)lague, 

 because an inoculation with hacilU and bacillus-germs, cultivated in such 

 an innocent and harmless fluid as milk, i)roduced the disease, whUe an 

 inoculation with blood-serum from diseased lungs — a highly infectious 

 fluid, if not deprived of its bacilli and bacillus-germs — remained without 

 the sMghtest effect after it had been freed from its bacilli and bacillus- 

 germs. I know very well that the«result obtained can hardly be consid- 

 ered as conclusive, and that some more experiments of the same kind are 

 needed to conflrm the conclusions arrived at. 



5. THE CONTAGION, THE CAUSES, AND THE NATUKE OF THE MOEBID 



PROCESS. 



That swine-])iaguc is an infectious disease, whicli can bo communi- 

 cated to heathy animals, has been demonstrated by my experiments. 

 It has further been proven that an exceedingly small quantity of an 

 infectious or contagious substance (blood-serum or exudation, for in- 

 stance) if inoculated, or directly absorbed by the vascular system, is 

 sufficient to produce the disease. It has also been ]Hoven that morbid 

 tissues and inorbid products, if consumed by healthy pigs, will cause 

 them to become aflccted with the i)lague. Consequently, two ways of 

 infection liave been ascertained Avith certainty. Further, if the results 

 of {ha po;-it-7nortem examinations are inquired into more closely, it will 

 be found that the principal morbid changes have occurred in the digest- 

 ive ca)ral, but especially in the cajcum and colon, in all those cases in 

 which tlie disease had been communicated by way of the digestive ap- 

 paratus ; and that, on the other hand, the ])rincipal seat of the morbid 

 process has been in the organs of respiration and circulation, or in the 



