P. G.
PANDE
41
smears, and in others it was based on the result of bowel-washing examination
only.
Not only was the disease limited to Government farm animals, but its
presence was later confirmed in individual private farms where Government
bulls had been placed for some time. Similarly, the disease, as a result of
the avian tuberculin test, was later detected amongst the indigenous cattle
of some of the villages where Government bulls were issued for breeding
operations. In view of the observations that the disease had its origin amongst
animals issued or sold from the Government farms, and that it was detected
amongst indigenous cattle herded with the farm-bred animals, it appeared
certain that further progress of the disease in the province could be checked
only by resorting to its proper diagnosis amongst farm animals, in and outside
the farm premises.
The incidence of the disease in Assam, as revealed by our investigation
extending over a period of four years, is not likely to reveal the state of affairs
with regard to this disease in other parts of India, for it should be realized
that the climatic and topographical conditions, peculiar to this province, have
to a certain extent determined the course and the progress of the disease in
Assam.
TOPOGRAPHICAL AND CLIMATIC CONDITIONS
These factors are mainly to be considered in the light of effects they are
likely to produce on the normal life and the health of cattle of the province.
Assam is essentially a hilly tract, comprising an area of about 53,015 square
miles intersected with numerous rivers, streams and natural water reservoirs
of various sizes, locally called bheels. On the map it is roughly triangular
in shape, the apex of the triangle being formed by the North-eastern Frontier
Tract. The main body of land has a slope towards Bengal as is indicated by
the flow of the Brahamaputra which forms the northern boundary of Assam.
The central part of Assam is occupied by ranges of Khasi and Jaintia hills,
and the part of the plains lying south of these hills is interspersed with several
small rivers, the principal of them being the Surma river. Thus the province
could be divided into three distinct tracts :
(1) In the north the Brahamaputra Valley consisting of six districts
which may be called Assam proper,
(2) the Surma Valley in the south consisting of two districts, and
(3) the hills.
Further it is a land of heavy rainfall and annual floods. Vast areas of
land which have not yet come under cultivation constitute the main grazing
reserves to which might be added such lands as get inundated during the mon-
soon, but are open for grazing during the winter period. The grasses, which
are wild and perennial in nature in the grazing reserves, and coarse and rank
in areas exposed to flood, do not usually contain much food value. The soils
in the plains of the Brahamaputra and the Surma Valley districts consist
mainly of clay suitable for rice cultivation, and may be divided into new
and old alluviums and the foot-hills. The old alluvium is composed of a light
layer of clay underlaid by beds of sand which in higher areas are more conso-
lidated and are closer and heavier in texture. The foot-hills are characterized