436 REPORT t>F THE COMMISSIONER OF AGRICULTURE. 



CONTAGIOUS . PLEURO- PNEUMONIA OR LUNG- 

 PLAGUE OF CATTLE. 



Prof. James Law, V. S., of Cornell University, l^ew York, has issued 

 a valuable work of about one hundred pages, entitled "The lung-plague 

 of cattle — contagious iileuro-pneumonia." This vrork is all the more val- 

 uable from the recent exjjerience of Dr. Law in the treatment of this 

 disease, for it will be remembered by many of the readers of this brief 

 review that he was last spring appointed by the governor of New York 

 to act as chief of a commission of veterinarians to assist the State author- 

 ities in devising and carrying out such, measures as it was hoped would 

 result in the complete suppression of this deadly malady among the cat- 

 tle of that State. He states many facts connected with the history of 

 the disease in this country not heretofore generally known, and also cor- 

 rects some errors and misapprehensions touching the disease itself which 

 English veterinarians have fallen into. He says that the name of the 

 disease {pleuro-pjieitmonia) has been largely misapprehended by the 

 medical mind, and that there is no proof that the malady, like other 

 imflammations of the organs within the chest, is caused by exposure, 

 inclement weather, changes of climate or season, imperfect ventilation, 

 &c. Other names have been, at different times, employed; for instance, 

 Ferqmeiimonia, Peripneumonia pecoriim enzootica or ejnisootica, Feripneu- 

 inonia exudativa enzootica or contagiosa^ Peripneumonia pecorum cpizootica 

 typJwsa, Pleuro-pneumonia interlobularis exudativa, Pneumonia cataj'^rlialis 

 gasirica asthenica, Pleuritis rliemnatica-exudativa. But Dr. Law regards 

 all of these terms as objectionable, and says if the term contagious {con- 

 tagiosa) be added to any of these definitions it only removes the diffi- 

 culty a short step, "for the i)hysician still concludes that the affection 

 is due to local or general causes, and that if it arises in one animal under 

 such circumstances it may in one million, subject to the same conditions; 

 that its general prevalence, at any time or place, may be altogether due 

 to the environment, and that the doctrine of contagion is either founded 

 on insufficient data or true only in a restricted sense and entirely sub- 

 sidiary to the generally acting causes. But the malady, as known to 

 veterinarians of to-day, is always and only the result of contagion or 

 infection." Therefore, a name better adapted to set forth the character 

 of the disease without the risk of misleading should be chosen, and for 

 this reason Dr. Law has adopted that of contagious lung-plague of cattle, 

 the new counterpart of the Lungenseuclie, by which it has long been 

 known in Germany. He regards the old i^vm, puhnonary murrain, 2i& 

 equally good. The German Lungenseuclie is especially apposite, the real 

 meaning being lung contagion, which conveys the idea of transmission 

 by contagion only. He therefore gives, as a definition of the malady, a 

 specific contagious disease peculiar to cattle, and manifested by a long 

 period of incubation (ten days to three months) by a slow, insidious 

 onset, by a low type of fever, "^and by the occurrence of inflammation in 

 the air iDassages, lungs, and their coverings, with an extensive exuda- 

 tion into lungs and j»leura3. 



After reciting the history of the malady in the Old 'World, in which 



