NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
PHEILERIASIS OF CATTLE IN INDIA.
21
HOST SUSCEPTIBILITY
All experimental evidence points to the conclusion that the parasite is specific
to cattle. Its infectivity was tested upon two buffaloes, two sheep, two goats and
a rabbit, but the results were negative.
INCUBATION PERIOD
The period of incubation of the disease, i.e., the time intervening between the
infective inoculation and the appearance in the circulating blood of either the
parasites or Koch's bodies or both, associated with an elevation of the body
temperature, was found to be 13 to 23 days, the average of about 145 reactors
being 16 days.
SYMPTOMS
The first noticeable symptom of the disease is an elevation of the body tem-
perature, which may be to the extent of 3 to 4 degrees or more above the normal,
this being accompanied by a running from the eyes, mouth and nostrils. The
animal, however, continues to feed well during the first two or three days after
the onset of these symptoms, but as the disease advances it develops progressive
inappetence, until eventually it goes completely off its feed. At the beginning of
the pyrexial period, the faeces are very hard, but diarrhoea soon sets in, and when
the disease runs a prolonged course, the evacuations are frequently mixed with
blood and mucus, although the urine usually remains unchanged. By this time,
the animal becomes greatly emaciated and assumes a recumbent position. In a
majority of cases, the prescapular and precrural glands are enlarged and tender,
whilst the visible mucous membrane of the eyes shows varying degrees of
icterus and petechiae. In a proportion of cases (Fig. 1), the temperature suddenly
drops down to subnormal before death ensues, but when death occurs early, the
temperature usually remains high, whilst in a few instances it has been found to
fluctuate within wide limits. A careful examination of blood smears taken at the
first rise of body temperature frequently reveals the presence, although in very
rare numbers, of either the parasites or Koch's bodies, and in a few instances both
have been observed in the same smear, but the presence of these is demonstrable
in large numbers only from about the third day of the disease.
In fatal cases, the disease usually runs a course of 3 (Fig. 2) to 11 days, the
average of about thirty-five cases being 5 . 5 days. Recovery, when it takes place,
extends over a period of 4 to 17 days, the average of nine recovered cases being
8.2 days (Fig. 3). It is of interest that in a few instances the parasites continued
to make their appearance, although in very small numbers, in the blood circulation
for about 2 days after the animals had, to all appearances, accomplished a clinical
recovery and had resumed their normal feeding.
22
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY.
FIG. 1. Somewhat prolonged incubation period (17 days). Temperature drops Suddenly to subnormal
before death occurs.
THEILERIASIS OF CATTLE IN INDIA.
23
FIG. 2. Incubation period very much prolonged (21 days). Duration of illness very short (about 3 days).
24
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY.
Ind. Jour.Vet. Sci. & Anim. Hus., Vol. VII, Pt. I.
PLATE VII
Theileria sp. (Type B), associated with Koch's blue bodies, as seen in acute infections in Indian (Hill) cattle × 1,000.
28
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [VII, I
POST-MORTEM APPEARANCES
The most constant post-mortem findings are a thin and watery character of
the blood, oedema and enlargement of the superficial and internal lymphatic glands
and of the spleen and a gelatinized condition of the body fat. There are petechiae
of the serous and mucous membranes and also of the epicardium and endocardium
and large numbers of irregular petechial marks on the larynx, pharynx and the
trachea. The lungs are frequently oedematous, whilst the abomasum usually
shows characteristic ulcers which may vary in size from a pea to a rupee coin, these
ulcers consisting of a central block of necrotic area surrounded by a haemorrhagic
zone. Similar ulcers, associated with petechial marks, may be found along the
whole length of the intestines. There may be haemorrhagic infarcts present in the
kidneys, but this has not been found diagnostic of the condition. The thoracic
and abdominal cavities usually show varying quantities of serous and sero-
sanguineous fluid.
Unfortunately little exact information, for comparison with the foregoing des-
cription, is available concerning the post-mortem appearances in the cases of
natural theileriasis that have occurred amongst imported Friesian bulls in this
country. In one of the animals that died at Lahore, the liver showed necrotic
patches with a yellow centre and a deep greenish periphery and extending through-
out the parenchyma, whilst the bile was "thick like the consistence of thin
porridge". The abomasum showed many minute petechiae confined only to
the centre, whilst the mucous membrane was found to contain " intense lesions
of a peculiar kind consisting of innumerable circumscribed small patches in all
stages of development into wellformed ulcers ". The post-mortem appearances
in, the case of two imported bulls which died at Kirkee consisted of an enlargement
of the liver and spleen, and in one of the animals the kidney, too, was enlarged,
whilst in the other there was evidence of vegetative epicarditis, associated with the
occurrence of petechiae under the epicardium.
VIABILITY OF STRAIN
A short series of experiments was carried out to determine the length of time
for which Theileria parasites remain viable both at room temperature (21°-22° C.)
and in the refrigerator. For this purpose, blood showing large numbers of these
parasites was drawn under sterile precautions and defibrinated before storage and
its infectivity was tested, at different intervals, upon bulls. It was observed that
blood kept at room temperature remained infective up to 96 hours and that stored
in the refrigerator completely lost its infectivity within six days.
LOCALIZATION OF " VIRUS "
In view of the opinion expressed by Richardson [1930] that the causal agent
of East Coast Fever might in reality be an ultra-visible virus, a series of
experiments, as detailed below, was carried out to test the infectivity of serum
and laked blood after these had been filtered.
THEILERIASIS OF CATTLE IN INDIA
29
Experiments with filtered serum.—Blood was drawn separately from two acute
cases of artificial theileriasis showing large numbers of Theileria and Koch's bodies
and was allowed to clot. The serum after separation was filtered through a Seitz
bacterial filter and each filtrate was injected into two bulls in about 10 c. c. doses,
the interval between the drawing of blood and the injection of the filtrate being
about 26 hours. The results were, however, entirely negative, and when later
tested for immunity by the injection of virulent blood, all the four animals proved
susceptible to the disease.
Experiments with filtered blood.—Blood from an acute case of artificial theil-
eriasis was defibrinated and haemolyzed by shaking with an equal quantity of
sterile distilled water. It was then filtered throngh a Seitz bacterial filter and the
filtrate injected intravenously, in quantities of 20 c.c. each, into two bulls, but the
results were negative. Both the bulls proved susceptible to theileriasis when later
tested for immunity with virulent blood.
IMMUNITY TESTS
The results of immunity tests are summarized in Table II.
TABLE II
Showing the results of Immunity test on recovered cases
Serial
No.
1
2
3
4
5
6
7
8
9
10
Hill
Bull
No.
537
14
1150
101
246
167
296
119
488
761
Date of infection
30th July 1931 .
20th June 1932 .
28th July 1932 .
27th September 1932
24th September 1932
24th September 1932
29th October 1932 .
19th December 1932
19th December 1932
5th February 1933
Interval
between recovery
and test
About 78 weeks .
„
35
„ .
„
29
„
.
„
22
„
.
„
22
„ .
„ 22
„ .
„
18
„
.
„ 12 „ .
„
12
„
.
„ 5 „ .
Result
Immune
„
„
„
„
„
„
„
„
„
Remarks
Natural case treated with
Plasmoquine.
Experimentally infected
and naturally cured.
Do.
Experimentally infected
and treated with Todorit.
Experimentally infected
and treated with Piro-
blue.
Experimentally infected
and
treated
with
Todorit.
Experimentally infected
and
treated
with
Trypafiavino.
Experimentally infected
Reaction mild.
Re-
covery natural.
Experimentally infected
and
treated
with
Plasmoquine.
Experimentally infected
and treated with Sul-
farsenol.
30
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [VII, I
An examination of this table shows that animals after recovery from the
infection develop what, to all appearances, is a solid and sterile immunity, this
being in contrast with the type of immunity observed in the imported bulls, for
in the latter case "it is believed that recovery from an attack leaves no real immu-
nity and that the animals almost certainly remain ' carriers ' of the parasite and
are liable to relapses at any subsequent time " [Cooper]. It will be observed that
in three out of the ten animals subjected to these tests, recovery had occurred
spontaneously, and this may afford an explanation for the fact that, as already
mentioned, nearly 47 per cent of the animals sub-inoculated with blood derived
from acute cases of theileriasis failed to develop the infection, for the resistance
exhibited by these animals might have been due to their having had attacks of
the disease early in life. A possibility of this kind is suggested by the fact that,
according to Walker [1930], " in young calves infested by hand with ticks contain-
ing a pure infection of Theileria parva it was not unusual to find a lower percentage
mortality as compared with adults infested by hand with the same batch of
infected ticks ". On the other hand, in a recent communication MacHattie [1935],
in Baghdad, has recorded the occurrence of a fatal outbreak of T. annulata infec-
tion amongst a batch of dairy calves which were only two to three weeks old, whilst
sporadic instances of similar infection have also been mentioned by Mason [1922],
Sergent and his collaborators [1927], Turnbull [1926], and Theiler and Graf [1928].
It is worthy of note that, with a few exceptions, all the animals in this in-
vestigation had been previously utilized in rinderpest work, and whether this fact
in any way determined the development of the theileriasis reaction in them is a
matter that would seem to demand attention.
IDENTITY OF PARASITE
In the confused state of our present knowledge concerning the systematic
position of the theileria parasites in general, it would be hardly profitable to enter
upon a lengthy discussion of the specific identity of those involved in acute or
fatal cases of the disease in India. As already indicated in the introduction, the
problem of theileriasis itself requires further clarification before any useful dis-
cussion can be undertaken concerning the identity of the parasites. Thus, the
condition met with in India would appear to comprise (besides T. mutans in-
fection) two distinct forms, which, for the sake of convenience, may be designated
as Type A and Type B, their position in du Toit's [1930a] scheme of classification
being as follows :–
32
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, I
It will be seen from the foregoing table that while Type A possesses characters
which are mostly identical with those described for T. annulata, Type B, although
it has the largest number of diagnostic points in common with T. dispar, neverthe-
less differs from it in the considerably higher rate of mortality.
It is to be mentioned, however, that du Toit [1930b] has expressed the opinion
that the name dispar should be regarded as a synonym of annulata and that the
latter should be regarded as valid on grounds of priority, so that there are only
three species of Theileria of cattle, namely, T. parva, T. annulata and T.
mutans* This view would also appear to be largely shared by Theiler [1930]
himself, as is evidenced by the expression " T. dispar or annulata " frequently
used by him. On the other hand, Donatien and Lestoquard [1931] have contend,
ed that it is T. annulata that should be sunk as a synonym of T. dispar and
T. mutans, whilst Sergent, Donatien Parrot and Lestoquard [1932] have even
referred to the possibility of T. dispar undergoing a morphological modification
towards the end of the acute stage of the disease and becoming completely
attenuated in virulence (presumably to the extent of being indistinguishable from
T. annulata).
It seems to the present writers that the case for T. annulata is better than that
for T. dispar, for whereas the latter name is almost exclusively applied to the
parasite found in Algeria, T. annulata (or parasites almost identical with it) has
been described from several countries around the Mediterranean Sea, including
those bordering on Algeria itself, e.g., Tunis [Ducloux, 1905] and Morocco [Velu
and Eyraud, 1915], so that it would appear more than probable that the Algerian
infection is merely a variant of the more widely distributed form of theileriasis
which goes by the name of Mediterranean Coast Fever and is believed to be due
to T. annulata.
It has, however, been pointed out recently by Yakimoff and his collabora-
tors [1932], that the proportion of round and rod forms of these parasites
varies within such wide limits in the different forms of theileria infections
that this character can hardly be of any value for classificatory purposes,
so that, considering the acuteness of the infection, the rate of mortality and the
type of immunity reaction, it cannot be regarded as altogether improbable that
Type B represents merely a variant of T. parva, but of depressed virulence.
On the other hand, the evidence is so overwhelming in favour of the view that
the parasite (Type A) concerned in outbreaks of acute theileriasis amongst imported
Friesian bulls belongs to the species T. annulata, that it is only necessary to con-
sider the possible manner in which these animals might have contracted the
infection. An examination of the history of some of these animals shows that, prior
to embarkation from South Africa, they were immunized against African "piro¬
* This is why Type B has been provisionally designated as T. annulata in the Annual
Report of this Institute for the year ending March 1933 (p. 29).
THEILERIASIS OF CATTLE IN INDIA
33
plasmosis ", by which term B. bigemina infection is doubtless meant. It is there-
fore reasonable to conclude that the clinical symptoms exhibited by a proportion of
these animals while en route to India, as already mentioned earlier in this paper,
cannot have been those of redwater, nor of T. parva infection, for in. the latter
event, the disease would not have run a chronic course, as was found to be the case
with a large majority of the animals. The possibility, therefore, suggests itself that
the organisms were acquired during the course of the voyage, the infecting material
having been, in all probability, tick-infested fodder. Evidence of this is further
afforded by the fact that the records in the possession of this Institute contain
particulars of two cases of theileriasis which occurred among Friesian bulls
imported direct from Holland. It would be idle to dogmatize as to the exact
locality where the infection might have been contracted, but it is probable that this
occurred at some point along the Mediterranean Coast, where, as is well known,
T. annulata infection is widely prevalent.
CURATIVE TREATMENT AND PROPHYLAXIS
A fairly large number of drugs—mostly chosen on account of their known
parasiticidal value—were tested as to their efficacy for this condition, the dosage
employed having been in accordance with the schedule laid down by the manufac-
turers themselves or based upon experience previously obtained in the use of these
drugs in the treatment of other diseases. As the results of these trials were, for the
most part, highly unsatisfactory, it would be hardly profitable to consider them in
detail. They are, however, summarized in the following table :—
TABLE IV
Serial
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Drug
Piroblue . . . .
Todorit . . . .
Trypaflavine . . .
Antimosan . . . .
Plasmoquine . . . .
S. U. P. 36 . . . .
Sulfarsenol . . . .
Novarsenobillon. . . .
Acriflavine . . . .
Myosalvarsan . . . .
Mercuric chloride . . . .
Bayer 205 . . . .
Antimony tartrate . . . .
Gonacrine . . . .
Sodium cacodylate . . . .
Asaphelene . . . .
Bayer 205 and Tartar emetic .
Quinine hydrobromide . . . .
Atebrin and Plasmoquine . . .
Atebrin . . . .
Total
Number of
animals
treated
5
6
5
11
8
3
9
6
11
3
6
7
5
7
6
5
11
5
8
19
146
Number of animals cured
1 (or 20.0 per cent)
2 (or 33.3 per cent)
2 (or 40.0 per cent)
Nil.
1 (or 12.5 per cent)
Nil.
1 (or 11.1 per cent)
2 (or 33.3 per cent)
3 (or 27.3 percent)
Nil.
2 (or 33.3 per cent)
3 (or 43 . 0 per cent)
1 (or 20.0 per cent)
3 (or 43 . 0 per cent)
1 (or 16.7 per cent)
1 (or 20.0 per cent)
2 (or 18.1 per cent)
1 (or 20.0 per cent)
1 (or 12.5 per cent)
11 (or 57.8 per cent)
38 (or 26.0 per cent)
F
34
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, I
It will be seen that recovery was obtained in only 38 of the 146 animals (26
per cent) used in these trials and that the best results were obtained with Atebrin,
whilst " Bayer 205 " and Gonacrine ranked second in the list. On the other hand,
some allowance has to be made for the fact that, in a small proportion of cases,
recovery has been found to occur spontaneously, so that the actual efficacy of these
remedies is probably less than that indicated by the percentages worked out above.
A short series of experiments was also carried out to test the value of the so-
called" premunition " against this disease, in view of the highly encouraging results
reported to have been obtained by Sergent and his collaborators [1931] against T.
dispar infection in North Africa by the adoption of this method. Twelve bulls
were each injected subcutaneously with 20 c. c. of blood drawn at the initial stage
of the disease, i.e., on the very first appearance of the febrile symptoms, it being
assumed that the blood so drawn would be free from parasites or Koch's bodies—
an assumption which also received support from the fact that the results of exami-
nation of blood smears taken at this stage of infection were consistently nega-
tive. Three of the twelve bulls mentioned above showed a definite reaction, as a
result of the injection, after the usual incubation period and one of them even-
tually died after showing symptoms of acute theileriasis. Six animals showed a
mild reaction lasting only for a day or two, whilst the remaining three animals did
not develop any symptoms at all. All the eleven surviving animals proved resistant
to theileriasis when tested by the inoculation of virulent blood about six weeks
later.
SUMMARY AND CONCLUSIONS
The acute or fatal forms of bovine theileriasis in India resolve themselves into
two well-differentiated categories, as described below :—
(1) Theileriasis in imported Friesian bulls.—The disease usually runs a chronic
course with periods of prolonged absence of any clinical symptoms, but it may
suddenly assume an acute form and rapidly progress to a fatal issue. The affected
animals exhibit an elevation of body temperature and sometimes also symptoms of
" pica ", whilst the visible mucous membranes are often markedly anaemic, al-
though this last may sometimes be negligible. Lachrymation and marked swelling
of the superficial lymphatic glands are also fairly constant features of the disease.
The examination of blood smears frequently shows only rare or few parasites and
Koch's bodies, but in a proportion of cases they may occur in large numbers when
the disease is at its height, the majority of the parasites being round or oval in form
and nearly 50 to 70 per cent of the red blood-corpuscles being invaded by them.
There is no solid or sterile immunity in this condition, but a state of premunition,
and recovered animals are liable to relapse. The rate of mortality amounts to 25
to 30 per cent. The outstanding features of post-mortem appearances are an en-
largement of the liver and spleen and the occurrence of petechiae in various organs.
THEILERIASIS OF CATTLE IN INDIA
35
The species of parasite concerned in this form of theileriasis possesses characters
which are mostly identical with those described by du Toit [1930 a] for Theileria
annulata, and all available evidence points to the conclusion that the infection is
exotic in origin, the organisms being probably acquired by the animals during the
course of their voyage to India.
(2) Theileriasis in Indian cattle.—This condition, which forms the main subject
of the present paper, has been extensively studied in artificially infected hill bulls,
the disease having been successfully reproduced in them by the inoculation of
virulent blood and organ emulsions, although nearly 47 per cent of the animals
proved refractory to the infection.
The average incubation period in artificial infection is 16 days, and in fatal
cases the average duration of the disease is 5.5 days, but when recovery occurs, it
extends over a period of 4 to 17 days. The principal symptoms consist of an
elevation of the body temperature, progressive inappetence and an enlargement of
the prescapular and precrural glands, whilst the visible mucous membrane of the
eyes shows varying degrees of icterus and petechiae. In a number of cases, the
temperature suddenly drops down to subnormal before death ensues, but when
death occurs early, the temperature remains high. The examination of blood taken
at the first rise of temperature frequently reveals the presence of rare parasites
and Koch's bodies or both, but the parasites rapidly increase in number as the
disease advances and may eventually invade 50 to 100 per cent of the red blood-
corpuscles, although Koch's bodies may vary in number from "rare" to
" numerous ". The parasites are usually seen as round forms, the " rods " being
rarely encountered. The rate of mortality amounts to more than 75 per cent.
The sequence of changes occurring in the blood of an affected animal has been
found to furnish a fairly reliable indication as to its chances of recovery. In the
event of the prognosis being good, the first noticeable change in the blood picture
is the occurrence of anisocytosis, this being followed by polychromatophilia and
granular basophilic degeneration.
The most constant post-mortem findings are a thin and watery character of
the blood, oedema of the lymphatic glands and of the spleen and a gelatinized
condition of the body fat. There are petechiae of the serous membranes and
respiratory tract, whilst the abomasum may show characteristic ulcers.
The parasites remain viable up to 96 hours at 21°—22°C., and when stored
in the refrigerator they lose their infectivity within six days. Blood showing
large numbers of parasites and Koch's bodies was filtered and the infectivity of
the filtrate was tested on bulls, but the result was negative. The serum derived
from such blood and treated in the same manner likewise proved non-infective.