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ANNUAL REPORT OF THE IMPL. INST. OF VETY. RESEARCH,
(3) Trypanosomiasis of sheep.—In view of the reported successful
transmission of the parasites of this disease (Trypanosoma melophagium)
to healthy sheep through the agency of the sheep-ked Melophagus
ovinus, some individuals of a local breed of sheep known to harbour
these flies were examined by Mr. Srinivasan for the presence of
T. melophagium in their blood, but the results were negative. A search
for these parasites, however, will be continued, as time permits.
(4) T. theileri ( = T. himalayanam) infection of cattle.—These
large trypanosomes have been encountered on one occasion during the
year in blood smears from a bull dead of experimental rinderpest, but
as the parasites could not be obtained in a living condition, no experi-
mental work with them could be undertaken. It is of interest that
forms intermediate in size between those of T. theileri and T. evansi
were not infrequently encountered in these smears and the question
therefore arises of the possible occurrence of polymorphism in the
case of these parasites.
(5) Dourine.—A perusal of the Reports of this Institute for the
past 15 years shows that, of the smears that have been received from
time to time for examination at this Institute, there has been a generally
progressive decline in the number of those that have proved positive for
the presence of T. equiperdum. Thus, the number of smears reported
as positive for the presence of these parasites have been, respectively,
11 for the year 1918, 14 for 1919, nil for 1920 and 1 for 1921, whilst
their number has been nil for each of the past 11 years. The reason
for this is not easy to understand, unless it be assumed that the
microscopical diagnosis of dourine is at the present time also carried out
at centres other than at Muktesar. During the year under report, some
smears of blood-stained urethral discharge from a suspected case of
dourine were received from the Army Veterinary Department for ex-
amination at this Institute, but a careful examination of these failed
to reveal the presence of the parasites of this disease.
(6) Trypanosoma lewisi infections.—Trypanosomes of this species
have on several occasions been encountered in the blood of wild rats at
Muktesar and some preliminary observations have been made by
Mr. Srinivasan upon the cultural requirements of these parasites, with
a view ultimately to utilize this experience in studying the behavi-
our of surra trypanosomes in vitro, for, curiously, although T. evansi
was originally described as far back as in the year 1880, it happens
to be the only pathogenic trypanosome of importance in regard to whose
developmental stages there is as yet no information on record.
II.—BOVINE PIROPLASMOSIS (sens. lat.).
(1) Redwater (Babesia bigemina infection): Drug Treatment.—In
view of the reported efficacy of the drug Piroblue for Redwater, some
trials were carried out with this drug in the treatment of natural Red-
water at Muktesar, and it was found that when used intravenously at
the flat dose of 25 to 50 c.c. of a 1 per cent. solution, it was thoroughly
efficacious even in acute cases of the infection. In view, however, of
the fact that we have an equally efficacious drug in Trypanblue in the