THE DURATION OF IMMUNITY IN CALVES INOCULATED BY
                        THE GOAT VIRUS CUM SERUM METHOD AGAINST
                                                RINDERPEST

                                                      BY

                                        P. C. BANERJI, G.B.V.C.,

Officiating Veterinary Deputy Superintendent, Imperial Institute of Veterinary Research,
                                                   Muktesar.

                 (Received for publication on the 13th September 1933.)

The results of experiments designed to test the duration of immunity in calves
inoculated by the usual sero-virus method at this Institute have recently been
published by D'Costa and Balwant Singh [1933] and the continuation of the work
with a modified virus will now be reported.

The introduction of goat virus for prophylactic inoculation against rinderpest
may be regarded as a notable advance in the development of such measures against
this disease in India, although our knowledge in regard to the precise value of this
product cannot, as yet, be declared to have reached a stage when it can be safely
recommended for use under all circumstances as a substitute for the more usual ox
virus. Nevertheless, this product would appear to meet the present demand for
a cheaper method of active immunisation for general application to the herds of
cattle in Indian rural districts in that, when goat virus is used, an efficient margin
of safety can be attained with a much smaller dose of serum than when ox virus is
inoculated. Indeed in many cases it would appear that serum may be dispensed
with altogether as shown independently by Kerr [1932] and by Stirling [1932].

Although considerable attention has been paid to the susceptibility of goats in
various parts of the world and Koch [1897] noted that virus when passaged through
goats became less virulent for cattle, the use of virus from this source for field
inoculations does not appear to have been considered a practical proposition except
by Bliss [1922] who recommended the use of goat virus in China, and Topacio
[1926] whose experiments proved the economy of the method. Edwards [1927] has
recorded the circumstances and the method which led to the establishment of a
rinderpest goat virus at this Institute, and he also emphasised the fact that this
virus was free from the serious drawback attendant upon the use of ox virus, in
that blood protozoan parasites, e.g., piroplasmata, are not infrequently introduced
along with the virulent blood.

A point of considerable importance, in regard to which little information is
available, is the duration of the immunity conferred upon cattle which have been

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