28
Horse No. XX.—Grey Australian Gelding aged 16 years. The animal
was kept under observation for some time and during this period appeared per-
fectly healthy. Attempt made to produce the disease in a somewhat similar manner
to that in which it is naturally contracted. Small quantities of blood were given
at short intervals in a large bulk of water by the mouth. On 4th, 9th and 11th
of May minims iv, viij, and vi of blood containing the hæmatozoon were re-
spectively given, followed on the 6th, 14th, 16th and 17th of June by varying
quantities, namely, minims viij, xxx, x and xxv respectively. As no symptoms
had presented themselves by the 28th of the same month and the blood present-
ed a perfectly healthy appearance on microscopical examination, two hundred
minims were given in water to the animal to drink, that is, fifty-six clays after
the first exhibition of the blood. With one exception between the 28th of June
and the 10th of September, the temperature never exceeded the normal range of
health, but on the latter date suddenly commenced to rise and from 37.5° C.
attained 40.4°C. by midday on the 11th. From this date until the 10th day of
the disease, the continued type of fever accompanied by daily remissions and
exacerbation was present. Then followed three well marked periods of fever,
the temperature gradually rising for several days previously and attaining a
maximum of between 4l°C. and 42.l°C. at midday on the 11th, 17th and 23rd
days of the disease, followed by somewhat sudden falls registering from 3°C. to
3.5°C. on the mornings following, each fever period being separated by one of
apyrexia varying from one to three days in length. finally presenting the
continued type of fever accompanied by remissions and a few intermissions at
irregular intervals between the 28th and 41st clays of the disease. The latent
period, if taken from the first exhibition of the soiled blood to the animal and
the appearance of the hæmatozoon in the general circulation, occupied one
hundred and thirty days, but if counted from the last exhibition„ then only
seventy-five days. On 19th September, i. e., the ninth day of the disease, a
slight Urticarial eruption appeared on the fore and hind quarters. Death took
place on the 21st October 1891, on the forty-first day of the disease.
Autopsy.—Emaciation, swelling and oedema of the extremities. Lungs
localized emphysema at the apices. The cavity of the pericardium contained
two ounces of fluid. One sub-pericardial extravasation, three-quarters of an
inch in diameter, was found lying on the muscular substance of the right ven-
tricle. Sub-enclocardial extravasations present in the ventricles. Liver old signs
of perihepatitis. Spleen normal in size, a few sub-capsular petechiæ. Stomach
presented a healthy appearance. Small intestines several circular extravasations,
no swelling or ulceration. Large intestines and rectum presented a healthy ap-
pearance.
Horse No. XXI.—Grey Country-Bred Gelding aged. Subcutaneously
inoculated on the 29th April 1891, with 1.0 c.c. of blood taken from the Jugu-
lar Vein of Horse No. XIX ante mortem, the hæmatozoon being absent from the
blood at the time. On the seventh day after the injection of blood a raised
tumor three inches in diameter was found occupying the seat of inoculation,
presenting the usual signs of tenderness and tension of the part on manipulation.
These conditions continued until the morning of the ninth day, when the tumor
was found to be flaccid and to have lost the previous symptoms. On examina-
tion of the blood of the general circulation microscopically the organism was
found in small numbers in it. The latent period occupied eight days. The
temperature commenced to rise from 38.2°C. on the last day but one, of the period
of incubation and continued uninterruptedly until the evening of the third day
of the disease, when it reached a maximum of 41.7°C. From this time it gra-
dually fell and attained a minimum on the morning of the fifth day of the disease
when the temperature registered 39.1°C. Five such periods of continued fever
took place in twenty-nine days, followed by well marked intermissions at some-
what regular periods, viz., a remission only on the fifth day, but intermissions
on the 12th, 19th, 24th and 28th days of the disease. Death followed the last
on June 4th. On May 10th slight hæmorrhage occurred from the inner canthus
of the right eye, which blood presented the hæmatozoon on microscopical exami-
nation. On May 15th two small irregular shaped extravasations of blood dark
in the centre and surrounded by a zone one-third of an inch in width of a lighter
colour was noticed, accompanied by a discharge of clear fluid from the same