79
occurrence, and appeared frequently as an early symptom. It first involved the
fetlocks more especially of the hind limbs, and gradually extended upwards
towards the hocks, the most noticeable features being the absence of heat and
tenderness on pressure. In horses it was frequently accompanied by swelling
and oedema of the sheath and scrotum and at a later date spread forward along
the under-surface of the abdomen, finally invading the sternal region. In mares
after the extremities had become involved, small patches of semi-solid œdema
were observed, on one side or other of the chest, or between the fore
legs. As long as an animal is able to assume the recumbent position, the exuda-
tion does not collect to any great extent, but as soon as the animal is condemned
to the upright position for any length of time, these accumulations increase,
and may attain to considerable proportions, as in the case of Horse No. XXI.
Arsenic when administered in full doses for some days, appears to have a
beneficial effect; the swelling and oedema gradually becomes less, and finally
disappears completely.
Effusion into the Joints.—This is sometimes met with, but is not of common
occurrence.
SECTION X.
DIAGNOSIS OF SURRA.
The demonstration of the ' Trypanosoma Evansi ' in equines will distinguish
Surra from all other febrile diseases. As the periods of intermission in this
disease vary in length from one to six days, so in order to positively exclude
the possibility of any cases presenting dubious symptoms being those of Surra,
it will be necessary to carefully examine microscopically the blood of the suspect-
ed animal daily for a period of ten days. If the result of the blood examination
should prove negative during the above-mentioned period, the case may then be
safely declared not to be one of ' Surra.' It must be borne in mind, however,
that a cursory examination of one cover-glass preparation of fresh blood on
each occasion will often prove insufficient, for it happens in the course of a
case, that several days or occasionally a week may pass, during which period only
one hæmatozoon may be discovered in two, or even three cover-glass prepara-
tions; this most frequently occurs at the commencement or termination of a long
paroxysm, or in a case of chronic Surra.
SECTION XI.
PROGNOSIS AND MORTALITY.
Always fatal in the horse, mule and camel, but in the bovine species after a
period, during which the animal suffers from fever, and the infusorian is present
in varying numbers in the blood, the animal generally returns to a normal state
of health.
TABLE XIII.
Showing the number of days which elapsed in seventy-six cases of naturally
contracted Surra in horses, between the date of the first appearance of hœmato-
zoon in the blood, and death.
less
1889
1890
1801
1892
Number of Days.
...{ Bombay Tramway Company ...
...{ Bacteriological Laboratory ...
...{Bombay Tramway Company .
...{ Bacteriological Laboratory ...
...{Bombay Tramway Company ...
...{ Bacteriological Laboratory ...
...{Bombay Tramway Company...
...{ Bacteriological Laboratory ...
...{Bombay Tramway Company...
...{ Bacteriological Laboratory ...
Total ...
Percentage ...
1
to
5.
3
1
...
...
...
4
5.26
6
to
10.
...
1
...
...
:::
1
1.31
11
to
15.
1
7
...
...
1
0
11.84
16
to
20.
2
8
...
...
2
12
15'78
21
to
25.
...
1
...
...
....
1
1.31
26
to
30.
3
6
...
...
1
1
11
14.47
31
to
35.
...
6
...
...
1
1
8
10.52
36
to
40.
7
3
1
2
6
7.89
41
to
45.
1
1
...
...
2
4
5.26
46
to
50.
...
5
2
1
8
10.52
51
to
55.
. 1
2
...
...
...
3
3.94
56
to
60.
...
1
1
...
...
2
2.63
61
to
65.
...
2
...
...
.1
3
3'94
66
to
70.
...
...
...
...
1
1
2
2.63
71
to
75.
...
1
...
...
1.
1.31
76
to
80.
...
...
...
...
...
...
106
to
110.
...
...
...
...
1
1
1.31
Total
number
of
Horses.
11
45
3
1
13
3
76
99.92