10
Vaccination Against Rinderpest
six showed a more or less severe reaction and recovered, while two died of acute rinderpest. As
some of these buffaloes were probably immune before vaccination, it appears that at best successful
' takes ' occurred in only a small percentage.
(iii) Owing to the hot weather, the temperature reactions in rabbits at the Military Veterinary
Laboratory were difficult to define and it was therefore decided to repeat the trial with fresh material
from Mukteswar and to use stronger suspensions of both liver and spleen. Accordingly, the 176th
passage in rabbits was sent in live rabbits, and was passaged once only at the Laboratory.
Material from this passage was inoculated into:
Group 1.—40 buffaloes at rate of 1 c.c. 1 : 100 liver suspension
Group 2.—40 buffaloes at rate of 1 c.c. 1 : 10 liver suspension
Group 3.—40 buffaloes at rate of 1 c.c. 1 : 100 spleen suspension
Group 4.—40 buffaloes at rate of 1 c.c. 1 : 10 spleen suspension
The reaction in five animals of each group were recorded in detail, but unfortunately owing to
an outbreak of what is believed to be buffalo-pox, the records of all but group 2 were vitiated. In
group 3, three animals showed an indefinite temperature reaction and diminution in milk yield.
Thirtyfive days later, three animals were chosen at random from each group and tested with virulent
virus. The only reactions were that one animal in group 1 and one in group 4 had severe reactions
and recovered, one animal in group 2 and one in group 4 had very slight temperature reactions. Un-
fortunately, experiments at Mukteswar, concurrent with the third trial, indicated that the virus had
by this time lost most of its invasive power for highly susceptible cattle.
Further work on rabbit passaging is now in hand, with the object of seeing (a) whether passages
between the 50th and 100th will regularly give a satisfactory vaccine for buffaloes, (b) whether the
attenuated rabbit virus can be transferred to hill bulls and maintained in them.
SUMMARY
1. Results are recorded of a small-scale experiment with virus adsorbed on alumina-gels.
2. Results of experiments on glycerolized vaccine are recorded. The findings of previous workers
on the value of such vaccines are confirmed, but to obtain entirely reliable results it is necessary to
increase the dosage and reduced the period of storage under glycerol. The method is somewhat
expensive.
3. Successful attempts were made to fix rinderpest virus in rabbits. For this purpose, it is
necessary to use a strain of high virulence for cattle. The virus becomes progressively attenuated in
rabbits, until it loses all or nearly all its invasive power for buffaloes and cattle. At intermediate
stages the virus appears to constitute a suitable vaccine, but the exact stage and method of main-
tenance are not yet defined. The virus in rabbit tissue is not present in large quantity and cannot
be stored for long outside the animal body. It can, however, be readily transported in the living
rabbit to areas within a range of seven days.
ACKNOWLEDGEMENTS
Our thanks are due to Brigadier E. S. W. Peatt, D.V.S. in India, Major F. W. Priestley, Capt.
K. J. R. Norkuman and Lt. A Wilson R. A. V. C. for assistance and co-operation and to Mr. C. Seethar-
aman for laboratory assistance.
REFERENCES
Bennett, S. C. J. (1936). J. Comp. Path & Therap. 49, 1
Daubney, R. (1928). Ibid 41, 228
Edwards, J. T. (1927) Trans. Far-East Ass. trop Med. 3, 699
—
(1924) Ann. Rep. Imp. vet. Res. Inst. 32
Haddow, J. R. and Idnani, J. A. (1941). Indian J. vet. Sci. 13, 113
Inoue, T. (1934). J. Jap. Soc. Vet. Sci. 13, 336
Kakizaki, C. (1918). Kitasato Arch. Exp. Med. 2, 59 Cited by Bennett (1936)
Morcos, Z. (1931). Vet. Rec. 11, 231
Nakamura, J. Wagatuma, S. and Tukusho, K. (1938). Jap. J. vet. Sci. 17, 25
Pfaff, G. (1938). Onderstepoort. J. vet. Sci. 11, 263.