2
from the jackal will be of interest, albeit melancholy interest, to sportsmen.
Captain Patton's work on Herpetomonas muscœ domestic, the type species of the
genus, is also of interest and value as completing our knowledge of the life cycle
of that parasite and showing how the presence of such " natural parasites " in the
intestines of flies capable of transmitting disease to man and other animals, might
enhance their capacity to do so. The differentiation of such " natural parasites "
from pathogenic ones found simultaneously in the intestines of blood-sucking flies
is also a subject, the importance of which has been but inadequately appreciated,
and which Captain Patton's methods of work should greatly facilitate.
PROGRESS NOTE BY CAPTAIN W. S. PATTON, I.M.S.,ASSISTANT
DIRECTOR, ON HIS PROTOZOOLOGICAL INVESTIGATIONS.
Since my return to the Institute in August 1909 I have devoted all my spare
time to the investigation of the pathogenic and non-pathogenic protozoa found in
South India. Although the work has progressed satisfactorily, many interesting
and important facts having already been ascertained, I am not in a position to
record the results in any great detail.
A long series of accurate observations has been started on the bovine piro-
plasmata of South India. So far two species of these parasites have been encoun-
tered., Piroplasma bigeminum, and a species of Theileria, allied to Theileria mutans and
Theileria annulatum. Captain Christophers, noted the occurrence of these
two parasites in 1905. As far as I am aware they have not been seriously studied
in India, and up to the present time it is not known by what species of ticks they
are transmitted. Piroplasma bigeminum is recognised by all observers to be highly
pathogenic, and the observations made here so far fully confirm this view; 8 calves
which contracted the disease died in from five to ten days. It is therefore of con-
siderable economic importance to ascertain to what extent it is responsible for the
mortality among cattle in South India.
Some 3,000 calves annually pass through the Vaccine Section, and as these
young animals are highly susceptible, it is possible to ascertain what percentage
have acquired the disease, escaped and thus become immune. In order to ascer-
tain this percentage' a routine examination of the blood of all the calves, a few
hours after they are brought to the Institute, was begun in August 1909 and up to
the 31st of January 1910, 1,477 calves had been examined. One hundred and
forty-three of these or 9 . 6 per cent. were found to be harbouring Piroplasma bigeminum
in small numbers in their blood. This percentage then represents those calves
which have contracted the disease and which have recovered and become immune.
It is very probable that at least 95 per cent. of the animals attacked by Piroplasma
bigeminum die, so that it would not be far wrong to say that about 65 per cent.
.of all calves born die, under one year old, of this disease This must represent a
great loss to the ryot, and as far as I am aware no account is taken of it, as it is
not even mentioned as being one of the causes' of mortality among the cattle of
South India.
Four species of ticks are found on the calves Hyalomma ægyptum in its
nymphal and adult stages, a species of .ficemaphysalis, Rhi picephalus, sp. ? and
Amblyomma, sp. ? in all their stages. I have been able to show that the species
of Rhipicephalus completes its life history on one animal and thus according to
some would be placed in the genus Boophilus ; this tick transmits Piroplasma
bigeminum in its larval stage, that is to say, larvae descended from an infected
parent are infective. This fora' of bovine piroplasmosis is therefore preventable;
and further, as Nuttall and Hadwen have proved, it can be cured by trypanblau
(Parasitology, Vol. II, page 156).
One thousand and fifteen calves or 68 . 7 per cent. have been found to contain
a species of Theileria in their blood; this parasite though closely allied to the highly
pathogenic Theileria parva, the causative agent of African East Coast Fever, does
not appear to be pathogenic. I am unable at present to say by what tick it is
transmit tied.