NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
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excreta, and that when used for horses' feed, the parasite may in that
way be conveyed into the horses' stomachs. In view of this theory we
think it right to mention that although the greater portion of our grain
is kept in paved godowns, and we do our best to exclude rats, yet we
know that both before and after the grain is received by us, rats do fre-
quently get at it. But before our grain is used for horses' feed, it is
carefully cleaned, both by band and through a machine. We ourselves
cannot, from our own observation, favour the rat infection theory. If
the source of the disease is due to grain getting mixed with the excreta
of rats, why is the appearance of fever limited to certain seasons, and
whys hould it appear only in certain years? For the past fourteen years
it has been unknown in our stables, and during those years our stocks of
grain and hay have been less well protected from the incursions of rats
than they have been during the past twelve months.
We have now, we think, exhausted all we are in a position to state
with regard to our own experience of "Surra" fever. We submit these
few remarks on a veterinary subject as proceeding of course from a non-
professional pen, and while we trust to be pardoned any mistakes into
which we may in consequence have fallen, we hope that our experience
may be of value to those who are making this disease a subject of special
study. As a large owner of horses, this Company is deeply interested
in researches which have for their object the discovery of a remedy for
this most fatal form of equine fever.
GEOGRAPHICAL RANGE.
The geographical range of this disease is much wider than it was
once imagined, and is one of the most important diseases affecting
equines met with in India. According to Evans, the natives of Dera
Ismail Khan on the North-Western Frontier, east of the Indus, have known
this disease for several generations as an occasional scourge. It has now
been recognised all along the low country bordering the Indus. In the
seventies at Asin, near Rajanpore, one cavalry regiment (3rd Punjab
Cavalry) lost 350 horses. In the late war it caused enormous mortality
among horses, mules, and ponies, used in Upper Burma, and according to
Steel ninety-eight per cent. died from it and Komree. Surra is endemic
in the Island of Bombay, and has been frequently recognised in animals in
the low districts lying below the Western Ghâts, called the Konkan, and
less frequently in other parts of this vast continent, separated from each
other by many hundreds of miles,—viz., in the Berars, in Meerut, and other
parts of the North-Western Provinces, as well as in Assam and Cachar.
Blanchard recognised this disease in Tonquin among the transport mules
belonging to the French Government. In 1876 a disease was pointed
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out to Haig in Persia, which he was told was invariably fatal, the cause
of which the natives ascribed to the animals drinking impure water.
On Haig's return to India he became acquainted with surra, and then
recognised that the Persian animals were affected with all the outward
ymptoms of that disease. There are reasons for believing that animals
have succumbed to this disease in Abyssinia, and probably also in Southern
Europe, Nroth America, Brazil, East Africa, and Australia.
Further information is wanted under this head.
Symptoms of naturally-contracted Surra.—Horse. The invasion
of this disease is usually marked by symptoms of a trivial character,
those of a slight attack of fever being the only ones noted. It may
occasionally happen that the fever may be accompanied or even preceded
by local or general urticarial eruption. If the blood be examined micro-
scopically during the period of fever, it will present a normal appearance
as regards the disposition of the corpuscles, etc., but certain rapidly-
moving organisms will be found, which induce in the corpuscles a peculiar
vibrating movement, which if once observed will not be readily for-
gotten.
If no microscopical examination is made, and the patient is treated with
febrifuges, it apparently regains its health. After an interval of a few
days during which the infusorian in its mature form is not present in the
blood, the animal again becomes ill, and on examination well-marked
symptoms are found; the skin is hot, the temperature more or less ele-
vated; the pulse is full and frequent, 54 to 64 beats per minute; the con-
junctival membranes, especially those covering the membrana nictitans,
are usually the seat of dark-red patches of ecchymosis, varying in size.
The thirst may be slightly increased and the appetite somewhat dis-
turbed. At the same time slight catarrhal symptoms, including lachry-
mation and a slight mucous discharge from the nostrils, may be present.
The submaxillary glands may, at this period, be slightly enlarged and
tender on pressure. At this stage some swelling and œdema of the
extremities, generally from the fetlocks to the hocks, which pits, but is
not painful on pressure, makes its appearance. This swelling gradually
increases in size, and invades at a later stage the sheath and under-surfaces
of the abdomen and chest.
If the blood be examined microscopically during the second paroxysm
of fever, the infusorian will be discovered. Following this second
paroxysm we have a period of apyrexia during which the infusorian in
its mature form is absent from the blood, also the intensity of the
symptoms is abated and the animal has a brighter appearance; the
temperature falls occasionally to normal. During the period of apyrexia
the ecchymoses gradually fade out; the pulse becomes weaker and
thready, but the appetite is excellent. In some cases the amelioration is
17
so marked, during the early remissions, that were it not for the presence
of the œdema and the falling off in condition, there would be little
to show that the animal is ailing. A third relapse or paroxysm, how-
ever, soon occurs, and all the symptoms are increased in intensity. The
action of the heart becomes irritable, the pulse full and quick, and at
times we note jugular regurgitation, the respirations are shallow. The
swelling and œdema increase very considerably. These paroxysms and
remissions continue, and the condition of the animal becomes steadily
worse. Towards the termination of the disease, it will be noticed that an
animal is disinclined to move, and when made to do so, it will be seen
that there is loss of command over the hind quarters simulating slight
paralysis, so that the gait is unsteady. We frequently notice paralysis
of the sphincter ani. These symptoms, taken together, point to some
interference with the normal functions of the spinal cord in the lower
dorsal and lumbar regions, and are probably caused by pressure due to
effusion within the spinal membranes.
In many cases shortly before death, the heart's action becomes very
violent (anæmic palpitation) shaking the whole frame at each beat, so
that the sound can be heard at some distance from the animal. In some
cases the animal suddenly drops dead, whilst in others the emaciation
and weakness become so pronounced, that the animal falls to the
ground and is unable to rise, and after a short bout of struggling, death
occurs. In other cases, again, the animal falls to the ground and
appears to suffer the most acute pain, struggles violently, sweats
bedew the body, and the respirations are very hurried. The struggles
soon exhaust the strength, and for a short time the animal lies quietly;
soon, however, the struggles commence again and continue until
death occurs. The principal symptoms then may be summed up as
follows:—Paroxysms and remissions of fever and the presence or
absence of the infusorian.
Progressive emaciation and weak-
ness, ecchymoses of the visible mucous membranes, the occurrence of
extensive œdema on the limbs, sheath, under-surface of the abdomen
and chest, progressive and pernicious auæmia, and death either from
exhaustion or from complications.
Symptoms of Inoculated Horse Surra.—The symptoms of surra
produced by inoculation differ in no marked degree from those of the
naturally-contracted disease. The only ones to be noted are those which
occur at the seat of inoculation. Twenty-four hours after the inoculation
(subcutaneous injection) of a small quantity of surra blood, in the great
majority of cases, a small, circumscribed, and somewhat raised swelling
is noticed at the seat of inoculation; alter forty-eight hours the tumour
has increased in size, and is accompanied by some œdema; it presents
a certain amount of tension of the parts involved, and is generally
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tender on manipulation. These conditions continue to increase until the
fourth day; the tumour may measure three or four inches in one direction
by two or three in the other, and be raised to the extent of an inch or
more above the surrounding tissues, from which it can be lifted.
According to the amount and the nature of the inoculated blood, so
will these symptoms rapidly develop themselves, until, after a period of
from four to thirteen days in the majority of cases, the tumour will
be found to have become less tense and tender; and when this is noticed
a microscopical examination of the subject's blood reveals the presence
of the infusorian. After this the tumour gradually disappears, and
the symptoms of surra are present, and run through their ordinary
course.
Symptoms of Inoculated Surra in Bovines.—To Dr. Lingard is
due the credit of having demonstrated the possibility of producing
surra in bovines, by the subcutaneous inoculation of blood containing
the infusoria, taken from the horse.
The symptoms noted at the seat of inoculation in the horse occur
also in bovines, and a few days after inoculation the infusorian appears
in the blood, and we have the symptoms of a mild paroxysm of surra.
Two or even more paroxysms may occur, but they are usually of a
mild character. After these mild paroxysms, in the majority of cases
the animal seems to be in perfect health, and no infusoria are, as a rule,
detected in the blood by microscopical examination, so that we should,
if we trusted to this method of examination alone, be led to the belief
that they had completely disappeared. Such, however, is not the case.
We inoculated guinea-pigs with the blood of a bull in which surra
had been produced, but in the blood of which no infusoria had been
detected for a considerable time,—83 and 165 days,—but strange to say
the inoculation was followed by virulent surra and the guinea-pigs
died.
Blood taken from the same animal produced no results when
inoculated into guinea-pigs, after 234 days, 267 days, and 356 days.
One bull was in perfect health 512 days after inoculation, and we
decided to subject him to re-inoculation with virulent material. The
result was negative, and he seemed to be protected. The course of
the disease in bovines may be summed up as follows:—One or two
mild paroxysms during which the infusoria are few; intermissions;
considerable loss of condition; recovery of health and condition.
Symptoms in the Sheep and Goat inoculated with Horse
Surra.—The disease behaves in a peculiar manner in the sheep. There
is little disturbance attributable to the action of the infusorian, which
appears to be unable to develop in the blood. The infusorian sometimes
develops in the fluid in the tunica vaginalis testis. Although the
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mature form was absent from the blood, it is interesting to note
that when blood was taken from a sheep 18 days after inoculation with
Horse Surra; and guineapigs were inoculated with the same, it caused
Surra.
Guinea pigs.—These animals present typical symptoms of the
disease; paroxysms and intermissions, gradual progressive anæmia, and
death.
Dogs and Cats.—The disease follows the same typical course;
œdematous swellings appear on the head, face, and limbs. There is pro-
gressive anæmia from which death results.
Analysis of Symptoms in the Horse.—Skin. An urticarial erup-
tion is occasionally noticed on the skin, about the time, or shortly
after, the infusorian enters the circulation.
Temperature.—It has not been possible to secure records of the tem-
perature of animals during the incubative stage of the spontaneous disease-
In inoculated cases the temperature curve has been variable, but ordinarily
in healthy horses it remains normal, or slightly rises after inoculation.
After the appearance of the infusorian in the blood, the temperature
varies very considerably, giving to the fever different types in different
animals. Hence in some cases we meet with a relapsing type, in others
a remittent; at first the rising and falling of the temperature is
concomitant with the presence or absence of the infusorian, but when the
disease has been running on for some time there comes a period, some days
before death, when the temperature remains elevated until immediately
before death, when it may become subnormal.
Pulse.—The pulse is, at the commencement of the disease, full and
strong during the paroxysm of fever, but seems normal during the fever-
free period: soon, however, as the anæmia progresses, we find that the
pulse becomes gradually weak and thready, and in many cases dicrotic.
It is naturally quick during the paroxysms of fever, and generally
regains about the normal number of beats during the apyrexial periods.
As Steel remarks, the tracing from the number of pulse-beats resembles
that from thermometer readings. Towards the end of the disease we
find the pulse much disturbed, increased in frequency and altered in
character.
Respiration—The respirations do not, as a rule, offer any marked
changes, following the course indicative of fever only.
Digestive apparatus.—The appetite is usually persistent throughout,
excepting at times when the fever is very high. This is a marked
peculiarity of surra, as in no case of other forms of fever do we find
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an animal exhibiting the appetite which we see throughout the course
of this disease. The tongue and mucous membrane of the mouth become
first pale and later yellow in colour. Small ulcers are often noted on the
sides of the free portion. The bowels are, as a rule, constipated, and we
have symptoms of hepatic disturbance in the colour of fæces, and the fact
of their being coated with mucus. Diarrhœa may come on towards the
end of the disease, but is not invariable.
Jaundice is a very constant symptom in every case at one period
or another. It sometimes appears early, and may be evanescent in
character, appearing with each paroxysm, and gradually fading during
the intermission. In the majority of cases, however, the yellow colour
of the membranes is intense and persistent.
Urinary System.—The urine changes in colour after the disease has
somewhat progressed, becoming viscid and green in many cases. The
reaction is usually alkaline until five or six days before the termination
of the attack, when it becomes acid. Albuminuria appears after the
disease has run a part of its course, the quantity of albumen passed
being very considerable as the disease progresses. Microscopical
examination of the urine generally reveals the presence of epithelial, blood,
and granular casts—signs of desquamative nephritis. The symptoms of
kidney disease, other than those found on microscopical examination,
are usually not well marked.
Organs of Vision.—Opacity of the cornea may be present, but it is
not common. Extravasations of blood into the anterior chamber are
occasionally met with. There is usually some lachrymation.
Organs of Smell.—Ulceration inside the nostrils has been noted by
Steel in some cases. There may be slight epistaxis; petechiæ are con-
stantly present on the Schneiderian membrane, which latter is often
tumefied. During the second week after invasion, there is a slight
discharge of clear fluid from one or both nostrils.
Course of the disease.—In the horse, the course of the disease is very
variable. The period of invasion has not been carefully observed in
naturally-acquired cases. We divide the disease into paroxysms and
intermissions. The periods of intermission are short, being of two or
three days' duration or less. The paroxysms last from two to twenty-one
days. Death occurs sometimes after the first paroxysm, but it may be
de'ayed until the seventh or even later.
Diagnosis.—The demonstration of the infusorian should always be
made. It must be remembered that it is not present in the blood con-
tinuously, being absent during the intermissions; so that it is necessary
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to make daily observations for a few days, if the first examination is
not satisfactory. The history of the case, the condition of the animal,
the presence of the œdema, and state of the membranes, lead us to
suspect the nature of the disease.
Prognosis.—Invariably fatal, no equine ever having been known to
recover.
Post-mortem appearances.—There are no specific lesions character-
istic of the disease. A general anæmic condition of all organs will be
noted. Some observers have noticed peculiar ulcers in the stomach in
Burma, but we have never met with them, nor have other observers
(Gunn, Evans). The heart generally presents some abnormal appear-
ance, the most common being very extensive sub-endocardial ecchymoses.
The kidneys often appear congested and ecchymosed, but not always.
Etiology.—Everything points to the infusorian (Trypanosoma Eransi)
as the vera causa of surra, although absolute proof is still wanting,
owing to the fact that it has not been obtained free from the blood,
etc. (pure), although numerous attempts have been made, so that we
have been unable to use pure cultivations of it for inoculation, and
the production of the disease. The following facts go to show the inti-
mate connection which exists between the organism and the disease:—
1. No case of "Surra" naturally contracted has been observed in
which the Trypanosoma Evansi has been absent, and all
previous authenticated cases investigated by such observers
as Evans, Steel, Pottinger, Gunn, and Rimington tend to
confirm this.
2. In all cases of the inoculated disease, the organism has been
present, and has comported itself in a similar manner to
that which has been observed in naturally-acquired cases.
3. By passing the infusorian through the organism of various
animals, and after it has been passed through a large number,
again bringing it back to the horse, fatal surra, with all its
distinctive characters, has again been induced, and the
infusorian has always been present.
4. The serum of blood swarming with the infusorian, when
passed through a porcelain filter, and thus deprived of the
infusorian, fails to produce surra on inoculation, and the
infusorian is never found in the blood of the inoculated
animal in these circumstances.
5. In addition to this, we have the undoubted influence which the
presence or absence of the infusorian has upon the course
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of the disease, dividing it, as it does, into its various stages,
viz., paroxysms and intermissions. It may be generally
accepted that the appearance of the infusorian in the blood
is quickly followed by a rise in the temperature, and, as a
rule, its disappearance is soon followed by a corresponding
fall. During the presence of the organism in the blood all
the phenomena of a paroxysm of "Surra" appear, while
after its disappearance there is a very marked diminution
in the severity of the symptoms. And so much is this the
case, that in some instances at the commencement of an
attack, an animal has been sent to work after the first
paroxysm, being apparently well.
That the infusorian is the vera causa of surra is also rendered more
probable by the fact that the disease is chiefly endemic in localities
which are, at certain periods of the year, favourable to the development
of low forms of animal life. This is believed to be due either to these
places being subject to inundations, or to their being low-lying and
swampy. In those cases where the infusorian gains access to the system
by means of the digestive organs, we must take into consideration the
influence which wounds and other lesions have in favouring its entrance.
In this regard, we find that out of 19 horses spontaneously attacked with
the disease, no less than 12 were the subjects of attacks of Spiroptera
megastoma or other parasites, which cause lesions of the gut. The
localities where surra is enzoötic belong to two distinct kinds of climates.
The one with a heavy rainfall, high temperature, and humid, steamy,
atmosphere; the other, a dry arid neighbourhood, presenting a great
annual range of temperature. But in both these classes of localities,
inundation of land during the rains leaves the fields covered with mud,
and evaporation and concentration of the water in the tanks occurs
during the hot season.
Mode by which the infusorian gains access to the system in
naturally-acquired cases.—Most observers are agreed in blaming
the water as a medium by which the infusorian gaius access to the
system, but no definite proof that this is the case has yet been adduced.
Sedgy vegetation, from inundated or swampy ground, is also suspected
to be a vehicle by means of which the infusorian may gain access.
Granted that the infusorian is the vera causa of the disease, it may
be logically deduced that we are justified in condemning the water
remaining after inundations, or that from low-lying stagnant pools
and wells, and also sedgy vegetation from places of a similar phy-
sical character, as we are well aware that such agents are favourable
for the development of low forms of life, infusoria, etc. But the
mature form has not yet been demonstrated either in stagnant water or
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on sedgy vegetation, so that we are unable to state with certainty that
these media really do convey the materies morbi. It is possible that
the infusorian does not exist in its mature form in either of these
media, but that there may exist an immature form which has not yet
been recognised. The excreta of rats has been blamed by some as a
possible medium, and no doubt on good grounds, for we know that
an infusorian apparently identical with that found in Horse Surra is
very frequently found in the blood of these animals, and that this being
the case, should any of the blood be passed with the fæces or urine, it
would be quite possible that surra might be induced in horses which
consumed them with their forage. Be this as it may, in Poona it has
been found impracticable to induce "Surra" by feeding horses with a
considerable amount of dung obtained from rats, in whose blood the
infusorian is present in large numbers (swarming). The infusorian can
be absorbed into the circulation from the digestive system, as has been
proved by giving small quantities of blood containing it in the drink-
ing water.
Contagion.—From the evidence we have at hand it would appear
that surra is not communicable by the sick to healthy animals, except
under certain conditions. The disease is not contagious in the ordinary
acceptation of the term. The contagium is neither conveyed by the
air, nor by the sick to the healthy, but gains an entrance with the food
and water, or is introduced by some form of superficial inoculation; and
it is necessary for one or other of these two forms of inoculation to
take place, in order that the disease be successfully transmitted.
The blood of an affected animal when introduced subcutaneously into
a healthy one, possesses the power of reproducing the same disease
whether the infusorian at the time of its withdrawal be capable of demon-
stration by microscopical means or not. As regards the quantity required,
it has been fourd that the fraction of a minim of soiled blood, containing
the infusorian, placed between the edge of a minute wound in the
cuticle of a healthy horse, was sufficient to reproduce the disease in seven
days.
Possibility of Contagion.—Taking into consideration the above
fact, it is easy to understand that there is some danger of the disease
being transmitted by the bites of certain flies, especially by blood suckers
armed with borers, for it is quite possible that a certain number of
the infusoria may be carried on the proboscis and inoculated into
healthy horses, specially when they are kept close together.
With the knowledge of the fact that a small quantity of blood in
water may, when swallowed, induce the disease, we may consider it
possible that the discharge from a sick animal, if containing blood, may