138
Contagious Pleuro-pneumonia of Goats
All animals evidenced profound depression after the inoculations.
Sterility tests.—Cultural tests made as described, with consolidated lung
tissue, pleural, and pericardial effusion, and the prepared inoculum revealed
no growth. Two guinea-pigs and two rabbits, receiving 2 c.c. intra-muscularly
and 1 c.c. intra-venously respectively of pleuritic effusion survived 26 days,
when they were slaughtered and found free from any lesions.
Results.—The surviving five goats of the experimental group developed
on the 2nd day after inoculation, lameness at both sites of inoculations (shoulder
subcutaneously and thigh intra-muscularly). During the succeeding two days
a progressive swelling developed at the above sites and the goats were dis-
inclined to stand or feed. No fever was present in any. One (No. 34),
with the most pronounced lesions, was slaughtered for transmission purposes
on the 14th of December 1938, 5 days p. ins. The remaining four died, as
shown in Table V, within the succeeding two days with the most remarkable
swellings at both the subcutaneous and intra-muscular sites of inoculation,
severe prostration, and a sub-normal temperature.
As previously mentioned none of the four control goats showed any
reaction or effect other than the temporary depression immediately after
inoculation. Two of these, Nos. 37 and 41, were subsequently tested for
immunity on the 19th of December 1938, 10 days later, by the inoculation
of virulent pneumonic lung emulsion, both proving susceptible. (Table
VI, Experiment 4).
Post mortem lesions.—Goat No. 34 was slaughtered as stated above
and examined. The lesions at both sites were opened up with aseptic pre-
cautions, and presented the same picture : massive oedema of the entire
region with enormous infiltration of clear, straw-coloured effusion into the
inter-muscular and subcutaneous connective tissues ; extensive necrosis of
the muscles, which were either pink or yellowish-grey in colour ; marked
congestion of the small vessels of the subcutis and inter-muscular septa, the
dilated vessels standing out in a clear net work in the oedematous bed ; and
oedematous enlargement of all regional lymph glands, especially the pre¬
crural. Though fluid on incision, coagulation of the effusion occurred within
two or three minutes of its liberation. The lesions extended from the croup
to the hock in the hind limb, where they were rather more advanced than in
the fore-limb. There was no gas-formation and no smell. All the residual
four goats showed identical lesions at autopsy.
Smears were made from both sites, stained by gram and examined, with
negative results.
Cultural tests were made from both sites on all media with the exudate
and from muscle, and with portions of muscle in liquid media. Stray colonies
of staphylococci resulted on the agar and blood agar only, with fluid from
the lesion on the hind limb only. All other cultures were sterile.
Mixed emulsion of muscle, with effusion, was prepared from both sites
using the same technique as for lung, and inoculated to goats and guinea-
pigs, without result in the latter as detailed in Experiment 3.
Of the other four goats, only one could be examined bacteriologically as
the remainder died over-night, and post mortem invasion was preclusive.
In this goat (No. 39), stray staphylococci were also isolated. Two rabbits
and two guinea-pigs inoculated intra-muscularly with 1.5 c.c. and 1.0 c.c.