ACTINOMYKOSIS. 
9 
extends into the mouth and the cancellated tissue of the bone, 
and is accompanied by abscesses and fistulse. In this situation it 
has been observed in the ox, pig, goat and dog. 
Only one instance has been recorded in the dog—that lry 
Professor Vachetta, of the Veterinary School at Pisa, and which 
was published this year under the heading of “ Macrocellular 
osteo-condro-sarcoma, with actinomycosis.” About two months 
before the professor saw the dog a swelling appeared, without 
any assignable cause, upon the posterior half of the right branch 
of the lower jaw, and rapidly increased in volume. In about 
twenty days the tense skin became ulcerated, mastication was 
difficult, And the animal was then brought to the clinic of the 
school. The ulceration of the skin was now somewhat extensive, 
and in the centre of this was a small hole, into which a probe 
could only be introduced two or three millimeters. The tumor 
was hard as a stone at the margin of the dental alveoli, but be¬ 
came softer towards the lower border of the jaw. With the ex¬ 
ception of the ulceration, the skin was otherwise healthy in the 
neighborhood. The tumor was not hot, neither did pressure upon 
it cause pain, but difficulty was evidently experienced in moving 
the second or third molar tdeth. Sometimes the upper jaw is implicated. . . 
At a spot on the side of the face corresponding to the roots of the third or fourth 
grinder, above or below, a small, hot, circumscribed swelling occurs. The ani¬ 
mal experiences no inconvenience from it, except when the part is struck or 
pressed upon. The tumor, however, grows, and pain increases. In some cases 
the growth is rapid, and in a few months the disease has invaded the larger part 
of one-half of the upper or lower jaw, and gives rise to severe symptoms, which 
arise chiefly from disturbed mastication, pain, and often from various cruel 
methods of treating the disease. The teeth become loose in their sockets, may 
be affected by caries, and dr«*p out. Anacker says that sometimes a fistula opens 
into the mouth. . . . It is evidently a morbid condition of the bony struc¬ 
ture. On dissecting the skin off the tumor, we find it covered Avith tough, 
fibrous tissue, arranged iu layers. The fibrous element diminishes towards the 
deeper parts of the growth, where at various parts yellow accumulations of a fri¬ 
able, calcular or granular matter are enclosed in solid cavities, surrounded by bony 
plates, or a tough, gristly tissue. M. Collignon, veterinary inspector of the 
slaughter-house of Montmartre (Paris), has observed the disease three times in 
three hundred oxen, and those he found affected came from the marshy plains 
of La Rochelle. In the plains of Ferrara, and iu the Maremme of Tuscany, the 
disease is very frequent. Low-bred animals are most subject to it, and its 
origin is usually attributed to a blow.” 
