2
5. Jacobabad.—Two sera, viz., Nos. VII and VIII, were deposited in the
office of the Collector of Jacobabad on the 17th January and retained there
until the end of July 1901. During this interval, the following maximum
shade temperature readings were recorded :—January 78.4° F., February 89.5°F.,
March 107.4°F., April 112.2°F., May 123°F., June 125°F., July 126°F. On
being returned to Muktesar and retested, No. VII was found to have lost 40
per cent. in protective power, i.e., a hill animal required a dose of 150 c. c. in
order to bring about protection by the Simultaneous method " instead of 90c. c.
per 600 lbs. as standardized at the time of issue. No. VIII serum, on being
re-tested at Muktesar, was found to have lost 66.6 per cent. in protective power,
i.e., a hill animal required a dose of 270 c. c. in order to bring about protection
by the Simultaneous method, instead of 90 c. c. as standardized at the time of
issue.
6. Madras.—No. VII serum was forwarded to the Superintendent, Civil
Veterinary Department, Madras, on the 20th August 1900, and after using a
certain quantity, the remainder was deposited in the above gentleman's office
until 18th November 1901, when at my request it was again despatched to
Muktesar for the purpose of re-testing. No. VII serum was standardized for
hill cattle at Muktesar at 90 c. c. per 600 lbs. body weight, and during its
deposition in Madras was exposed to a maximum temperature of 108.5°F. in
June 1901, during which month the highest annual thermometric readings are
recorded. On re-testing at Muktesar on hill cattle, it was found that instead
of 90 c. c. being required to protect this susceptible breed of animals, 200 c. c.
per 600lbs. were necessary. It will, therefore, be observed that this sample of
serum (No. VII) had lost 55 per cent. in protective power.
7. Burma.—Nos. VII and VIII sera were forwarded to the Superin-
tendent, Burma, on 9th November 1900, and were retained in that gentleman's
office until the time of his respective inoculations during April to November
1901, a period of 6 to 12 months. During this interval the maximum tem-
perature of the year, 104°F., was registered in April, the hottest month in
Burma. It will be seen by that officer's report, paragraph 31, that " he was
equally successful with the Simultaneous method," after injecting the labora-
tory standard doses. For this reason, the serum which had been exposed to a
maximum temperature of 104.1°F. did not appear to have lost in protective
power, but it must be noted that these experiments by the Simultaneous
method were carried out in plains cattle in Burma, and not on the highly
susceptible breed of hill cattle utilized at Muktesar, which can only be
protected by the injection of 18 times the doses necessary for plains animals.
8. From the above recorded experiments, it will be seen that samples of
sera Nos. VII and VIII, deposited in Jacobabad, and exposed to a tempera-
ture rising to 126° F., lost in protective power respectively to the extent of 40
and 66.6 per cent. in comparison with the standardized dose registered when
issued. In Madras, a sample of No. VII serum was found to have lost in protec-
tive power to the extent of 55 per cent. when exposed to a temperature
rising to 108.5°F. While in Burma, samples of the same sera (Nos. VII and
VIII) were tested by Veterinary Captain Evans, after being exposed to a
rising temperature of 104'1°F., and were found to have retained their protec-
tive power when utilized by the Simultaneous method," equally as when used by
the serum alone method. In the latter instance, however, it must be noted
that a sample of the Burma serum, after exposure, had not been re-tested at the
Laboratory on hill cattle, and that all Veterinary Captain Evans' experiments
were carried out on plains animals, which in many instances possess a more
or less degree of immunity, either hereditary or acquired, so that 1/18 th
of the dose of protective serum required by hill is sufficient to bring about the
necessary immunity in plains cattle. It must be stated that at Muktesar the
sera kept for long periods through hot and cold seasons, do not deteriorate in
their protective value, and it is a well-known fact that the specific action of
normal and of bactericidal sera is entirely lost, if allowed to stand or warmed
to 55° C., or 131° F. Consequently, from the above experiments, it will be
apparent that the protective power of the above sera has been materially
diminished after exposure to a much lower temperature than 131°F., viz., to
108.5°F.