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A lobular broncho-pneumonia simulating infectious pneumonia 
very closely is not inirequently found in young pigs. It is described 
on p. 485. It seems to follow collapse. ~ 
Lung worms (Strongylus paradoxus,.*)—Are frequently found in 
the falland winter. They first appear in the extreme end of one of the 
large bronchi, 2. e., in the caudal tip of a principal lobé. Here they 
may be detected as small, hard nodules, not larger than a small pea. 
The lung tissue around them may be hyperzemic, or perhaps in a state 
of hepatization. The presence of the worms will in all cases explain 
the lesions. ; 
More advanced changes are well illustrated by a case which came under our ob- 
servation recently. Each principal lobe contained-four masses about three-fourths 
of an inch in diameter and very hard to the touch, The cut surface was coarsely 
granular, the granules yellowish, imbedded in a pale red parenchyma, and probably 
representing plugs in the smallest air tubes and alveoli. The trachea and bronchi 
contained large quantities of gelatinous mucus. The bronchi leading to the hepa- 
tized regions were completely occluded with lung worms. There was not pleuritis. 
In hog cholera the lung lesioms are quite insignificant compared 
with those of other organs. In the acute type there is usually a 
hemorrhagic condition. The entire surface is dotted with subpleural 
blood extravasations. On section the lung tissue itself is found to 
contain these hemorrhagic foci. Excepting the occlusion of a few 
alveoli here and there with blood, there is no inflammation or hepa- 
tization perceptible in any part of the lung tissue. 
' In chronic cases of hog cholera these hemorrhages either never | 
take place or else they are speedily absorbed, for the lungs are, as a 
rule, healthy, if we except the collapse of the small ventral lobes now 
and then encountered as above described. 
When the sternum of a diseased animal is removed the ventral 
lobes which overlap the apex of the heart only during a full mspira- 
tion do not collapse and drop out of sight into the thorax, as in the 
normal lung, but they stand up over the heart as two solid masses, 
of a deep red, mottled with yellowish points, or more grayish, accord- 
ing to the stage of the disease. If these lobes are normal the dis- 
ease, as a rule, does not exist in the remainder of the lung tissue. 
Frequently they are glued to the wails of the thorax and the peri- 
cardium. 
The appearance of the lungs will thus lead to an easy diagnosis of 
swine plague as distinguished from hog cholera. The intestinal 
lesions which accompany swine plague in its most severe forms are 
not so easily differentiated from lesions produced by hog cholera, but 
a careful attention to descriptions given in the foregoing pages will 
solve this difficulty in most cases. The disease of the large intestine 
in swine plague is essentially exudative. Necrosis of the superficial 
layer of the mucous membrane is secondary, the resulting ulcers 
superficial. In hog cholera the lesions are at ‘irst either hemor- 
rhagic or necrotic (ulcerative), or both. There is little or no exudate 
preceding the stage of ulceration. 
SUGGESTIONS AS TO THE MEANS OF PREVENTING THE SPREAD OF 
SWINE PLAGUE. 
Experiments with the microbe of this disease have shown that it 
has very feeble powers of resistance to external agencies. It is ‘xilled 
* See p. 282 of the Report of the Bureau of Animal Industry for 1885. 
