THE OCCURRENCE OF BOVINE CONTAGIOUS PLEUROPNEUMONIA
IN ASSAM*
By V. R. GOPALAKRISHNAN, G.M.V.C., Veterinary Investigation Officer, Assam
(Received for publication on 12 September 1942)
(With one text-figure)
CONTAGIOUS bovine pleuropneumonia or ' Lung
Plague ' is undoubtedly one of the most serious
cattle diseases causing considerable losses. Bal-
drey and Williams [1909] and Hutyra and Marek
[1926] mention the occurrence of the disease in
India; Edmonds and Walker [1929] doubt its
existence in this country while Edwards [1927]
considers that India has escaped its ravages.
Similarly, a perusal of the available annual reports
of the Provincial Civil Veterinary Department
indicates that opinion was always divided as to the
existence of the disease in India.
In the last few years some work has been done,
in collaboration with the Imperial Veterinary
Research Institute, Mukteswar, to investigate the
disease, as it occurs in Assam. Efforts were made
to study in detail the incidence and epidemiology
of the condition. The first outbreak that the
writer had the opportunity to investigate was in
Deosiri grazing area, Goalpara district, in the
month of January 1940. A study of the epidemic
was undertaken, and suitable materials were
collected for examination at the Imperial Veteri-
nary Research Institute, Mukteswar, and for
preliminary transmission experiments at Gauhati.
As more outbreaks occurred in other centres,
further material was obtained for experimental
work, and additional information relating to the
disease was collected. The disease has so far
been investigated in three districts of Assam.
Careful field observations suggest the specific
and contagious nature of the infection. A few
forms of pneumonia of different etiology are known
to occur in cattle, but the specific nature of this
condition was really noteworthy. Almost identi-
cal clinical syndromes in affected animals in various
centres of outbreak, similar courses of the disease
with high mortality and uniform post mortem
lesions strengthened the suggestion of its contagious
nature and specificity. Transmission experiments
carried out in Assam gave sufficient evidence
that the disesae can be reproduced in cattle, and
that goats were resistant, thus confirming the
observations in the field. The causal organism
of the disease, as it occurs in Assam, has been
isolated at the Imperial Veterinary Research
Institute, Mukteswar, from natural cases, the first
one being from Deosiri area. The organism was
reported to belong to the same group as that of
Pleuropneumonia Contagiosa, i.e. Borrelomyces
peripneumoniae. A strain of the organism ob-
tained from Sibsagar was also found to be immu-
nologically identical with the original Assam
strain. There seems to be substantial evidence
now to show that the disease, as it occurs in
Assam, is the same Contagious bovine pleuro-
pneumonia as, occuring in other parts of the world.
Besides, in India this disease seems to have been
in existence only in the province of Assam.
Geographical and climatic conditions of Assam
It appears necessary to give a brief description of
the natural features and geographical and climatic
conditions of the province to appreciate fully the
epidemiology of the disease. Assam is essentially
a land of hills and valleys abounding in forests
and ample vegetation. It is a land-locked province
forming the north-eastern frontier of India, al-
most touching Tibet, China and Burma. The
general topography presents numerous undulations
consisting of hills and dales. There are two
main valleys—the Brahamaputra and the Surma—
that constitute mainly, though not entirely, the
whole province. Sloping downwards from the
Bhutan Hills, or the foothills of the Himalayan
range on the north, numerous tributarias, big and
small, flow southwards to join the Brahamaputra.
To the south of the river, there are many hill
ranges—Khasi and Jaintia Hills, Garo Hills, etc.
The districts of the Brahamaputra or Assam valley
lie on either side of the Brahamaputra river, ex-
tending from Lakhimpur in the north-east to
Goalpara on the west. Further south of the hill
ranges that border the Assam valley lies the Surma
valley, named after the river which flows in that
area.
In the Brahamaputra valley, where the occur-
rence of the disease has been recorded, extensive
forest areas and low-lying marshy tracts, which are
inundated during rains and floods, border the
course of the river. Vast areas of land, with rank
and wild grasses and coarse herbage, constitute
the main grazing reserves. Cattle are maintained
in these areas in groups in places known as khutis.
Besides, there are many islands in the bed of the
river, known as charson charland, which are very
fertile, and cattle are kept there for cultivation
as well as for grazing.
The climate of Assam is humid, and the rainfall
is high. The winter season is short, and dry
* Paper read at the Indian Science Congress (Section
of Medical and Veterinary Research), held at Calcutta
in January 1943.
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