342 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, IV.

It will be observed that only two out of the 22 calves inoculated reacted at the
time of the orginal inoculation and in conformity with the findings when ox virus
was used as reported by D'Costa and Balwant Singh (loc. cit.), the reactions
occurred in the oldest group of animals. Considering the dose of serum and the
comparatively low virulence of the virus used it is surprising that any reaction was
observed at all. One of these animals was tested twelve months later and proved
to be solidly immune. The other died before the completion of the test period.

Of the remaining thirteen animals which survived the allotted test period and
which showed no reaction at the time of the initial immunisation, one was tested
after twelve months' interval, four after approximately 18 months, four after
approximately 24 months, and four after approximately 30 months. The reac-
tions noted at the time of the test were :—2 calves tested at 18 months developed
a temperature reaction; in one of these, the reaction was apparently due to a mild
attack of rinderpest, the other which developed temperature of 105°F. on the
fourth day after inoculation returned to normal on the 5th day, no other symptom
was observed and in the opinion of the writer this reaction was not due to rinderpest
but in the absence of sub-inoculations into susceptible hill bulls the case must
remain doubtful. Three of the four animals tested at about 24 months developed
mild attacks of rinderpest which, in the case of 2 animals having a thermal reac-
tion only, were confirmed by sub-inoculation into susceptible hill bulls of blood
withdrawn on the 6th day after the test inoculation. The sub-inoculated bulls
succumbed to rinderpest. Two of the four calves tested after 30 months reacted to
the test, the temperature reaction in each case being followed by a short period of
inappetence. No sub-inoculations were done from these calves.

Whilst a considerable amount of further work will have to be done before it is
possible to arrive at a definite conclusion in regard to the value of goat virus when
used in conjunction with anti-serum in the protective inoculation of cattle against
rinderpest, the results summarised above would seem, at any rate, to point to the
conclusion that the degree of immunisation obtained with this product is adequate
for the purpose of protecting against death for a period of at least 31 months.
At the same time it must be noted that even at 24 months and possibly even at
18 months a certain proportion of these animals can contract the disease in a mild
form and may, therefore, presumably act as disseminators of infection for at least a
short period.

The results do not indicate that the interval between immunisation and retest
is a factor of great importance in the exhibition of a reaction or otherwise, although
it is probably of very considerable importance as regards the degree of severity of
the reaction produced, In conformity with the results published by D'Costa and