INFECTIOUS BRONCHO-PNEUMONIA OF CATTLE. 



Synonyms. Corn-stalk disease. 



History. This has been known for a length of time in Amer- 

 ica, as appearing more particularly among cattle shipped from 

 the West, and sometimes attacking, at intervals, all or nearly all 

 of an entire shipment of cattle that had been subjected to the 

 same environment, but without showing the disposition to indefi- 

 nite propagation as an epizootic, contagious disease, which charac- 

 terizes lung plague. In common with the broncho-pneumonias 

 developed by the foul air and overcrowding on the Atlantic 

 steamers, it gained a great notoriety in Europe where it was at 

 first mistaken for the genuine lung plague. In 1888, Billings re- 

 ported it as the corn-stalk disease, attributing it to a bacteridian 

 parasitism of the stalks of Indian corn. In France it was studied 

 by several veterinarians in imported American cattle, and chiefly 

 by Nocard, who made cultures of its microbe and inoculations 

 with pure cultures, and definitely established the contention of 

 W. Williams, in Scotland, that it was a form of broncho-pneu- 

 monia entirely distinct from lung plague. 



Causes. The essential cause of this affection is a bacillus about 

 I ju, long by 0.3 to 0.4 /t thick, highly motile, easily stained in 

 aniline colors, aerobic (facultative anaerobic) and growing lux- 

 uriantly in buillion cultures, of a neutral or alkaline reaction. 

 On peptonised gelatine growth is slow and spare, producing a 

 thin, transparent, bluish pellicle with deeply notched borders like 

 a fern leaf, and without liquefaction of the gelatine. On gelose 

 it grows luxuriantly. On potato it grows slowly and sparingly 

 forming a delicate, grayish film which shades off insensibly at the 

 borders. The germ has great vitality retaining its virulence for 

 a length of time in artificial cultures. 



Nocard inoculated the bacillus in pure artificial culture success- 

 fully on mice, rabbits, Guinea-pigs, pigeons, cattle and sheep. 



Inoculations on chickens, dogs and cats were negative. Two 

 or three drops in rodents or pigeons caused death in forty-eight 

 hours, with intense congestion of the mucosas generally, but with- 

 out local lesion in the seat of inoculation. Injection into the 

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