292
Bovine Contagious Pleuropleumonia in Assam
(d) At Patabari two goats were kept intimately
in contact with two sick calves in the same shed,
feeding and drinking water being common.
One calf died on the third day and the other ten
days later. The goats kept under observation
for three weeks remained normal.
The experimental reproduction of the condition
in goats was unsuccessful. That goats were not
susceptible to natural infection has been ascer-
tained in all the outbreaks where investigation
was undertaken. Hence, the infection appears
to possess specific pathogenicity to bovines.
In this connection it will be of interest to refer
for comparative study to contagious pleuro-
pneumonia of goat occurring in Madras, the
etiological agent of which has been designated as
Borrelomyces peripneumoniae capri [Longley, 1940].
In regard to experimental transmission, it is stated
that cattle do not appear to be susceptible to
inoculations of massive particulate inocula con-
sisting of pneumonic lung, along with the effusion
of affected goats. In the field conditions also,
the disease was known to affect goats only [Visva-
nathan, 1937]. Similar experience has been
reported in East Africa too. Mettam [1929]
states that ' the specificity of caprine contagious
pleuropneumonia may be proved by the im-
possibility of infecting other animals than goats
with pathological material '. Conversely, goats
were found to be resistant or insusceptible to
inoculations with pleuropneumonia material of
the bovine origin in Assam. Hence, it seems
evident that the causal agents of bovine and cap-
rine pleuropneumonia, though belonging to the
same group, capable of manifesting a pathological
condition apparently similar, are different- posses-
sing specific species infectivity.
LABORATORY FINDINGS
As a routine, micorscopical examination of
smears of affected parts, exudates, effusions,
etc. was carried out. Preliminary cultural test
was also undertaken locally. No organism of any
significance could be found. Coliform and bipo-
lar organisms (Pasteurella ?) and Cocci were
observed. Heart blood cultures were usually
sterile. It would appear necessary to refer to the
isolation of Pasteurella organisms in these cases.
Shirlaw [1939] refers to the striking similarity
between the pulmonary lesions of contagious
bovine pleuropneumonia and the more subacute
lesions in haemorrhagic septicaemia. The usually
rapid course, so characteristic of haemorrhagic
septicaemia in Assam, is conspicuously absent
in the outbreaks of bovine pleuropneumonia.
Even the isolation of bipolar organisms from the
lesions of the lung and pleura would generally
be deemed as secondary or terminal invader.
Requisite material and full information were
sent to the Imperial Veterinary Research Institute,
Mukteswar, for detailed research. It was reported
that the etiological agent of bovine Pleuro-
pneumonia, as it occurs in Assam, has been isolat-
ed and that "it (causal organism) passes with ease
through Berkefeld 'V' filter and is readily culti-
vable on serum agar. It has been maintained
by passage in hill bulls.
*
*
*
*
There is a probability that this organism belongs
to the same group as that causing Pleuropneu-
monia Contagiosa, i.e. Borrelomyces peripneu-
moniae".
Further, fresh material from outbreaks in differ-
ent districts of Assam, as far apart as possible,
was called for by the I.V.R.I. Hence suitable
material was sent from Majuly area, Sibsagar
district. The affected locality is situated nearly
300 miles north-east of Deosiri area. As a result
of the laboratory tests, it was reported that this
strain was found immunologically identical with
the original Assam virus obtained from Deosiri
area.
TREATMENT AND CONTROL
Treatment was attempted in animals in the
early stage of the disease with Novarsenobillon—
' N.A.B.' (M. & B.). Of course, advanced cases
and those showing pronounced lung involvement
were avoided. The dosage was 0.3 gm. for
calves and 1.5 gm. for adults in 5 to 10 c.c. of
distilled water intravenously, as was tried in
Gold Coast Colony [Stewart]. It is further stated
that
'N.A.B.'
had given
'marvellous
results' in cases of contagious bovine pleuro-
pneumonia. Fifteen cases were treated, and they
were under observation for a month. Ten of
them recovered. In the recovered cases the
abatement of symptoms was gradual in the course
of five to eight days, and subsequently they ap-
peared bright, feeding normally. Cases that did
not respond to the treatment died in the course of
7 to 17 days. Previous attempts to treat cases
with formalin, iodine, etc. did not give satisfactory
results. From the experimental treatment with
'N.A.B.' it appears that the results are promising.
As regards control, restriction on the sale and
movement of cattle from the infected areas was
recommended. Isolation of sick cattle and segre-
gation of newly purchased animals, particularly
from suspected localities, were advised.
With regard to vaccination, preliminary field
trials with contagious bovine pleuropneumonia
vaccine prepared at the Imperial Veterinary
Research Institute is now in progress in Assam.
The product used is a culture-virus-vaccine
tested by tail-tip inoculation (Willems' method).
On completion of the preliminary trial, large
scale immunization is contemplated.