282
"Actinomycosis" and Actinobacillosis in Animals
The pericardium was unevenly but markedly thickened, and showed the
disease in a more severe form, the entire organ being involved and more or less
thickly covered with papilliform growths. The connective tissue reaction
was severe and in the form of a highly vascular granulomatous tissue,
as before, wherein foci of wandering cells, by no means rich in polymorphs,
were seen. In these foci thickly felted masses of a Gram-positive Strepto-
thrix (Plate XXII, figs. 2 and 3) could easily be detected. There was, however,
no definite club-formation, although a slight swelling of the peripheral ends of
some of the filaments was suggested. The filaments showed an uneven Gram-
positive character and the cell-collection around the ray-colony was at places
very scanty.
A most remarkable feature of the pericardiac lesion was the presence, in
the granulomatous tissue, of eggs (Plate XXII, fig. 4 and Plate XXIII, fig. 1)
which in caustic potash preparations were observed to be operculated. No
worms, or evidence of eosinophilia was noticed. The eggs were, in all pro-
bability, of a trematode, and in view of the thoracic situation of the lesions
and of the reported existence of the lung-fluke Paragonimus westermani from
dogs in South India, the ova, by their size, may well have been of this species,
although no worms were detected by Mr. Mutappa at autopsy. How these
eggs came to be situated in the lesions and what part, if any, they played in
the causation of the " actinomycotic " disease are questions which cannot be
readily answered.
Although Streptothrix infection in canines is definitely rare, various
authors have, from time to time, observed its occurrence in other parts of the
world, and some of them have expressed the identity of the causative organism
with A. bovis. Vachetta [1882] was the first to detect " actinomycosis " of
the jaw of a dog. Rivolta [1884] described a purulent pleurisy in a dog due
to an unbranched leptothrix type of organism. Rabe [1888] described three
cases of " actinomycosis " of the dog ; in two there was suppurative phleg-
mon, and in the third a blood-tinged purulent peritonitis was observed. A
filamentous organism, Cladothrix canis (Rabe), was seen in the actino-bodies.
Rabe [1888] succeeded in transmitting the disease to a dog by inoculation of pus
from the third case, and recovered the organism. Hartl [1901] met with one
case of " actinomycotic " tumour in the mediastinum and thoracic wall. Bahr
[1904] described " actinomycosis " of the dog and cultivated the causative
streptothrix. Schnelle [1929] described the case of a dog, similar to that of
Mr. Mutappa, but wherein abscesses appeared on the skin which showed on
autopsy an effusive pleurisy with reddish cloudy exudate, granulations on the
pleurae, broncho-pneumonia with consolidation, and greyish nodules in the
lungs throughout. Microscopically, Streptothrix canis was detected. Feldman
and Mann [1932] described an extensive granulomatous condition of the sub-
mucosa of the dog's stomach with typical actino-bodies with clubs but without
a demonstrable central Gram-positive filamentous mass either in sections, or
in culture, or by animal inoculation. Histologically, their case resembled to
some extent the one encountered by the author in a bovine [Spec. 1557/1929
(p. 277.)]. Sheather [1932] reported a finely divided papilloma-like growth
removed from the thoracic cavity of a dog, which histologically revealed the