46
Pleuropneumonia in Goats
areas of grey hepatization; a greater part of the left diaphragmatic lobe
showed consolidation in the red hepatization stage and a zone of spread; the
pericardial sac contained about 30 c.c. of blood-tinged fluid and the linings
of the pericardium and the surface of the myocardium were found covered
with shreds of fibrin.
Case 596. Areas of consolidation were found in both the lungs, but only
the apical and the cardiac lobes of both were completely consolidated ; some
parts of these lobes were oedematous with prominent interlobular septa and
the others had passed into the stage of red hepatization; areas of grey hepati-
zation were, however, absent; the whole apical and cardiac lobes of the right
and a part of the cardiac lobe of the left were covered with a gelatinous clot of
pleural exudate; the diaphragmatic lobes showed a few irregular haemor-
rhagic infarcts. The pleural cavity and the pericardial sac contained
each about 100 c.c. of clear straw-coloured fluid.
In experimentally reproduced cases, the nature of the lesions did not
materially differ from those of the field cases, except in their extent and
distribution according to the routes of inoculation of the culture or other
infective material.
In the majority of cases injected by the intratracheal route, the lesions
appeared first in the right lung, involving the apical lobe first and later extend-
ing to other lobes of the same side. If the animal did not die or was not
destroyed at this stage the left lung also showed involvement chiefly of the
cardiac lobe. Very few cases infected by this route showed lesions in the
remaining two lobes of the left lung.
Lesions resulting from the intravenous and the subcutaneous inocula-
tions of the infective materials were uniform in distribution in both lungs
and appeared in the form of haemorrhagic infarcts or patchy consolidation.
A few cases in which infection was obtained by contact with the affected
animals, and by feeding of infective materials showed consolidations in
both lungs and areas of red and grey hepatization were present in each lobe.
The lung lesions in experimental cases appear in the form of a more or less
extensive consolidation (Plate V, fig. 1) involving one or more than one
lobe, either completely or partially. In the case of a partial involvement of a
lobe, the diseased part has always been found demarcated from the healthy
lung tissue which beyond the line of demarcation shows a typically congested
zone of spread. Apart from the diffuse type of lesion, one could see particularly
over the diaphragmatic lobes scattered areas of patchy congestion simulating
haemorrhagic infarcts, when recently formed, which with the progress
of the disease may be transformed into typically consolidated areas. Areas of
red and grey hepatization seen easily through the opaque and usually thicken-
ed pleural covering revealed a variegated appearance on section (Plate V,
fig. 2). In an acutely inflamed lung tissue the interlobular septa have been
distinctly seen from within the pleural covering (Plate V, fig. 1), and on section-
ing the lung tissue at this stage of hepatization, a small amount of red-tinged
fluid escaped from the cut surfaces. The cut ends of the bronchioles were
observed to be patent, although on squeezing a frothy mucoid discharge
exuded from them. The portion of the lung tissue involved in red hepatiza-
tion looks more compact and firmer in consistency and the cut surfaces, with