148 Contagious Bovine Pleuro-pneumonia in British India
The fact that we hear little more of this disease after 1905-06, when
bovine hæmorrhagic septicæmia sprang, more or less suddenly, into promi-
nence lends weight to this view. The outbreak of bovine pleuro-pneumonia in
Ferozepore area affecting 138,000 bovines was, on prima facie evidence one of
hæmorrhagic septicæmia. This outbreak remained peculiarly localised and it
is well known that this is exactly what does happen during an outbreak of
hæmorrhagic septicæmia. The disease, originating in an area of dense cattle
population flares up quickly to a climax, when the majority of animals in that
area are affected and then suddenly abates, recurring again with less severity
the following year and succeeding years, until, on the emergence of a new
generation with little inherited resistance, the disease again makes its appear-
ance in epizootic form.
The peculiarity of these epizootics is their tendency not to spread to ad-
jacent herds. Contrast these facts with those known about bovine pleuro-
pneumonia. This disease occurs insidiously and slowly in a herd and " after
the introduction of the disease it is usually weeks before it becomes manifest
and months before all the susceptible animals have become affected in stall and
still longer in the case of animals at pasture. In the case of affected animals
infection recurs continually and may become established on
farms for years when even apparently cured animals may transmit the virus
to the fresh arrivals " [Hutyra andMarek]. This succinct expression of the
epizootiology of contagious bovine pleuro-pneumonia is one that has never
been observed in cattle herds in India and conversely the epizootiological
features of hæmorrhagic septicæmia are well known to and frequently en-
countered and commented upon by workers in the field.
It is impossible to conceive localised outbreaks of contagious bovine pleuro-
pneumonia. When it makes its appearance in a country previously free from
the disease the effects are disastrous. " The disease has decimated herds
throughout Europe and in other parts of the world on several occasions and
probably has been directly responsible for the death of more cattle than any
other single disease with the possible exception of cattle plague (Rinderpest)."
[Miller, 1935]. As an illustration, the disease was reintroduced into Great
Britain in 1860 and in that year one hundred and eighty-seven thousand head
of cattle died. One has no hesitation in affirming that if this disease did exist
in India much more would have been heard of it. The silence of the last three
decades on the subject is practically certain evidence of its non-existence
and the reports of sporadic outbreaks (Sind, etc.), appear to enhance the
evidence. Contagious bovine pleuro-pneumonia, as already observed is not
a sporadic disease.
The outbreaks reported in recent years from Assam have been fairly fully
dealt with and the evidence goes to show that this form of bovine pneumonia
is certainly not true contagious bovine pleuro-pneumonia associated with a
Borrelia infection. It is true that the lesions bear a striking resemblance to
the latter disease but comment has already been made on the fact that a form