MUKTESAR, FOR THE TWO YEARS ENDING THE 31ST MARCH, 1924 45
In the agglutination test upon sera obtained from the animals in an
infected stud, the distinction between reactors and non-reactors is often
not a sharp one, as is usually observable in applying the method for the
detection of infection with common form of contagious bovine abortion,
—hence, the large proportion of " suspicious" reactors recorded in the
above table.
Some experiments were carried out at the laboratory upon the nature
of the infection. The execution of this work was mainly in the hands of
Mr. M. B. Menon.
(g) Surra. The experiments carried out at the laboratory, mainly
by Mr. Timoney, were planned in order to discover an effective, cheap,
and easily applicable system of treatment for adoption in the field. Sup-
plies of tryparsamide were obtained by the courtesy of Dr. Louise Pearce,
of the Rockefeller Institute for Medical Research, New York, U.S.A.,
and tested upon natural cases of surra in horses at the laboratory and
in the field. The results were very disappointing, considering that this
drug is the organic arsenical compound which has given the most promis-
ing results in the treatment of human sleeping sickness, A beneficial
effect was clearly manifested after the first injections of large doses but
the effect was not sufficient to prevent relapses, and subsequent injec-
tions displayed steadily decreasing action, presumably because the
trypanosomes had become "drug-fast." Nevertheless, for a prelimi-
nary rapid nearly complete sterilisation of the system the drug was
promising. For reasons of economy, however, the efficacy of cheaper
drugs for the treatment of animals had to be exploited, and for the test-
ing of the effects of single doses the buffalo proved a very suitable animal
when it had become infected with a highly exalted strain of the surra
trypanosome. This virulent strain in 1923 produced death almost
invariably in the buffalo in a few days, but intervention with an adequate
dose of tartar emetic intravenously during the septicæmia produced
rapid recovery, and the buffalo's own strengthened defences were after-
wards usually sufficient to prevent a relapse. Likewise, it was found
that the administration intravenously of a suitable dose of an insoluble
bismuth salt (bismuth phosphate suspended in a mucilage of gum acacia)
produced a rapid, clinical " cure " in the buffalo. The treatment of
animals with a relatively high natural resistanec, such as cattle—and,
probably camels also must be reckoned as such—is therefore a compa-
ratively simple problem, but the prospects of curing the very susceptible
species of hosts, such as horses, do not seem to be very hopeful.
(h) Mange. In the prosecution of serum manufacture at Muktesar
with the use of buffaloes as serum producers it was noted that these
animals became seriously affected with mange during eight to nine months
of the year, and that the affection disappeared spontaneously during
the remaining months, May till August. Both the sarcoptic and psor-
potic forms of parasite were responsible for the condition, and during
the year 1922-23 the study of the sarcoptic parasite was pursued sys-
tematically by Mr. Timoney. His main objects were to ascertain infor-
mation concerning the life-cycle of the parasite and of the resistance of