123
It will be seen from the accompanying Table of Treatment, that the first
satisfactory results were obtained by the employment of the mixture of Cinchona
Alkaloids and Arsenic—vide cases LXV and LXXII. In the former the hæma-
tozoon disappeared after six days of treatment, and remained absent for a period
of twenty-seven days. But it was found that after the drugs had been ad-
ministered for twenty-six days, symptoms of gastric irritation appeared, which
were due to the Alkaloids, and consequently this form of treatment had to be
discontinued, just at a critical stage of the experiment.
Arsenic alone had still more favourable results as regards the destruction of
the hæmatozoon, as will be seen in the following table :—
TABLE XVIII.
Horse
No.
LXXVII ...
LXXVI
...
LXXX ...
LXXXII ...
LXXIII. ...
Days of Treat-
ment to dis-
appearauce
of hæma-
tozoou.
8
5.5
2
2
3.5
Amount of Arsenic
to date of dis-
appearance.
82 grains
56 „
12 „
16 „
41 „
No. of days hæma-
tozoon absent.
26
27
44
64
84
In the above cases, the cause of death was usually Arsenical poisoning, and
this was owing to the fact, that great difficulty was experienced in determining
the length of period for which the chemical should be administered. It will be
remembered that to prove the absence of the Surra organism from the blood,
other animals have to be inoculated from the animal under treatment.
In the ordinary cases of Surra, where no treatment has been adopted, the
latent period, when Guinea-pigs are inoculated, is only about a week ; but when
the fluid for inoculation is taken from an animal that has been subjected to pro-
longed Arsenical treatment, the latent period is extended to about three weeks.
and this time must elapse before the above question can be decided. During this
period the administration of Arsenic has to be continued, hence the animal may
receive far more than is necessary for the total destruction of the organism.
Such results have been obtained from no other form of treatment, and I
think it is rational, that in the future further experiments and investigations
should be made, with a view to determine to what degree the administration of
Arsenic can be safely carried. It is well known that no satisfactory results can
be obtained without first producing the preliminary symptoms of poisoning by
this metal.
B.—THE SUBCUTANEOUS INOCULATION OF BLOOD AND ITS DERIVATIVES IN ITS
DIFFERENT FORMS, OBTAINED FROM ANIMALS SUFFERING FROM, OR WHICH
HAD LATELY SUCCUMBED TO, SURRA.
A series of experiments were conducted, in order to test the efficacy or
otherwise of the blood serum, as a protective agent against inoculated ' Surra,' or
in other words to ascertain whether any substance capable of conferring immunity
against the disease was present in it, when obtained from animals in whose
circulation the hæmatozoon of Surra had been swarming for some days previ-
ously. In the first series, fresh blood containing numerous hæmatozoa was
drawn from the horse immediately after death into sterilized glass vessels, and
set aside for several hours in order to allow of the serum separating. The
serum was then transferred to one of M. Pasteur's filters, and forced through a
porcelain cylinder. Three rabbits and two Guinea-pigs were then subcutaneously
injected with varying quantities, during a period of three days. On the evening
of the third day each animal received subcutaneously 0.2c.c. of blood containing
numerous hæmatozoa, another animal in each case receiving a like quantity so as
to act as control experiments.
Rabbit A, which received 3.0c.o. serum after inoculation with the soiled
Surra blood, survived the first appearance of the hæmatozoon twenty-four days.