( 17 )
buffaloes, the dose being repeated in some cases. The details and dates will be
found in Appendix XXXV.
208. The result of the test, which is, of course, far more searching than
the animals are likely to be put to under ordinary circumstances, has been that
none of the animals showed any outward signs of Rinderpest whatever, but the
temperature of K/L 4 rose 4/5 of a degree F. on the 6th day, and the temperature
of Kv. rose from 102 to 103.4 F. on the 6th day. (See Appendix XXXV).
209. I have to add that a subcutaneous injection of 1/1000 part of 1 c c m.
of virulent blood is sufficient to cause the usual visible symptoms of Rinderpest
to develop according to Dr. Kohlstock.
210. Amongst the various Bile experiments carried out at Belgatchia
those of the 11th September assumed considerable importance in regard to the
duration of the immunity conferred by Bile, because three animals inoculated
on this date with 10 c.c.m. of the Bile from a bullock that had died on the 10th
September of Rinderpest were subsequently attacked with natural Rinderpest,
and one died, thus:—
Bullock JA. was attacked 4 months and 15 days after inoculation, and died
quickly.
Bull JA. 1 was attacked 4 months and 24 days after inoculation.
His
attack was very mild.
Bull JA. 2 was attacked 5 months and 5 days after inoculation. His
attack was mild.
211. It will therefore be seen that the test cattle at Kanti treated with
buffalo's Bile, though subjected to what I consider to be a much higher test, did
not take Rinderpest, whereas animals treated with bullock's Bile that died of
naturally acquired Rinderpest took the disease naturally.
212. Though it is dangerous to generalize too early in experimental work
it seems safe to point out—
(a) That buffalo's Bile used under the circumstances recorded may be
expected to confer a longer immunity than the Bile of bullocks
that die of the disease.
(b) That in an overwhelming majority of cases the buffalo Bile method
which was used at Kanti, confers immunity for an average
period of not less than five months. The duration of the immu-
nity is probably longer, but how much longer can only be
settled by actual experiment.
(c) That it has been clearly proved that there is no danger of the inocu-
lation with Bile conveying Rinderpest, if the work is done as
I do it, viz., according to Koch's teaching.
(d) It has also been clearly proved that the operation does not interfere
with the ordinary work of the bullocks.
213. My experiments show that the buffalo Bile method may be employed
with advantage and safety on Wards' Estates, &c , when Rinderpest is prevalent
in the neighbourhood, for it would probably confer immunity long enough for
the disease to die out in the surrounding villages; and in all probability the
raiyats seeing the advantages to be gained by having their cattle inoculated,
would gradually permit their animals to be treated in the same way.
214. For the present the buffalo bile method is the simplest way of con-
ferring temporary immunity on cattle in Bengal, but it has the obvious drawback
that a delay occurs in obtaining the bile in necessary quantity and purity. It
cannot be obtained from the cattle for local reasons. A further delay of about
seven days occurs while the inoculated cattle are acquiring immunity, because
they do not become immune at once. Hence twelve very important days at
least are lost.
215. It has been accepted as a principle by the workers in South Africa,
and I believe elsewhere, that immunity extending over a very long period can
only be acquired after an attack and recovery from Rinderpest. In attempting
to confer immunity to animals by a system based upon this principle, the preli-
minary difficulty is of course to control the strength of the attack which is to
confer immunity, otherwise a large percentage of the animals would die.
216. Though I am not yet prepared to offer a definite opinion as to
whether constant control can be maintained over the virulence or mildness of the
D