4
20 c.c., of anti-rinderpest serum will be ample to give protection by the
"Serum alone" method for a period of several months.
13. Anthrax.—The opinions expressed by me in the concluding portion
of my letter No. 526, dated the 29th August 1900, with regard to the prepara-
tion of a serum for Anthrax and Anthracoid diseases, were approved of by the
Viceroy in Council, as referred to in Government of India, Revenue and Agri-
cultural Department, No. 54 of 1900, dated 4th October 1900, to Her Majesty's
Secretary of State for India. Consequently, during 1900-1901, experiments
were taken in hand with a view to the preparation of a protective serum
against Anthrax, which has been further developed and brought to a successful
issue during the year under review.
14. The mode of procedure adopted for the purpose of immunising animals
was similar to that utilized in the case of rinderpest, except that enormous
quantities of Anthrax material had to he prepared in bouillon and cultivated
in the incubator for several days and later injected subcutaneously, instead of
the injection of virulent blood as in rinderpest. The other details with regard
to repeated injections at intervals, are somewhat similar to those used in the
preparation of anti-rinderpest serum.
15. From the date on which the initial experiments for the purpose of
protecting the selected animal against Anthrax, to the date of the first bleeding,
for the purpose of collecting the serum, a period of from four to five months
must elapse, and even then only one bleeding can be effected, and another
injection of virulent anthrax cultivation has to be made in order that a subse-
quent bleeding may follow. As the experiments progress, it is hoped that a
shorter period will be required to produce a more highly efficient serum.
16. In the preparation of a protective Anthrax serum, plains and hill
cattle, and in addition buffaloes have been utilized for the purpose. Our
researches have elucidated the following important facts amongst others :—
(i) The inoculated disease in this country runs a course in plains animals
of from 70 to 144 hours, and in hill cattle from 35 to 120 hours.
(ii) The hill breed of cattle, as in the case of rinderpest, is much more
susceptible to Anthrax than the plains, and it has been observed
that a weak culture of the Bacillus Anthracis, which had no effect
on several plains animals, readily brought about a fatal result in
the more susceptible breed, viz., Himalayan cattle, as well as in
equines, sheep and goats.
(iii) With regard to the protective power exercised by the anti-anthrax
serum manufactured up to the present, it has been proved that
plains animals, of about 300 to 100 lbs. and over two years of
age, require a dose of 10 c.c., whilst the hill breed of animals, 150
to 200 lbs. in body weight, require a dose of 50 c.c., that is,
the small Himalayan cattle must receive at least five times the
dose given to plains breeds.
(iv) It is a point of great importance, however, to remember that young
cattle under two years of age, require a much larger dose of this
protective serum than adult animals of the same species.
17. Lymphangitis Epizootica.—During the year under review, 134
specimens of tissues and pus taken from suspected animals were received at
the Laboratory from different localities dotted over India, for examination and
report. Of the total number of specimens, 70, or 52 per cent., were found to
contain the Cryptococcus of Lymphangitis Epizootica, and in 64, or 47.8 per
cent., the organism was absent.
18. Through the courtesy of the Director, Army Remount Department,
I was enabled, on 25th March 1900, to initiate a number of comparative
experiments in equines, bovines, buffaloes, sheep and goats, with a view to
determine to what extent, these animals were susceptible to Lymphangitis
Epizootica when subcutaneously inoculated with fresh material just collected
from a recent case. On the 27th March 1902, after a period of over two years,
and at the request of the Director, Army Remount Department, I determined
to destroy the experimental animals in order to find out whether any of them
had lesions in their internal organs. A few weeks after the primary inocula-
tion of the Lymphangitis Epizootica material containing the Cryptococcus,