THE LUNG PLAGUE OF CATTLE. 



THE BOYTNE PNEUMONIC PLAGUE.— PLEUEO- 

 PNEUMONIA CONTAGIOSA. 



Nomenclature. — Generally known in English veterinary 

 literature as Pleuro-pneumonia, this affection has been 

 consequently largely misapprehended by the medical 

 mind. It is naturally assumed that the malady, like 

 other inflammations of the organs within the chest, is 

 caused by exposure, inclement weather, changes of cli- 

 mate or season, imperfect ventilation, etc., etc. There is, 

 however, no proof that such is the case, and hence it is 

 impolitic to retain a name which is misleading to the ed- 

 ucated mind, and conveys no definite conception to the 

 uneducated. Other names that have been at different 

 times employed are equally objectionable : Peripneumo- 

 nia, Peripneumonia pecorum enzdotica or epizdotica, Peri- 

 pneumonia exudativa enzdotica or contagiosa, Peripneumonia 

 pecorum epizdotica iyphosa, Pleuro-pneumonia intpiobvlaris 

 exudativa, Pneumonia catarrhalis gastrica asthenica, Pleu- 

 rifis rheumatico-exudativa. If we add the term contagious 

 {contagiosa) to any of these definitions we only remove 

 the difficulty a short step, for the physician still con- 

 cludes that the affection is due to local or general causes, 

 and that if it arises in one animal under such circum- 

 stances, it may in one million subject to the same condi- 

 tions, that its general prevalence at any time or place 

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