NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
ABSTRACTS
125
The viscous oil had a flash point Cleveland 540°F. maximum; viscosity at 100°F.
Saybolt Universal 2,900-3,200; pour point + 50°F. maximum ; colour A. S. T. M. 2.0
maximum ; carbon conradson 0.5 per cent maximum ; and sulphur bomb 0.5 per cent
maximum. (B. C. B.)
The influence of frequency of cutting on yield, chemical composition,
digestibility and nutritive value of some grass species. J. G. Louw (1938),
Onderstepoort J., 2, 163-244
I NVESTIGATIONS were carried out on five indigenous grasses grown under natural
conditions of soil and climate. The experiment covered two successive growing
seasons 1935-36, 1936-37. The following frequency of cutting was applied :
1. Cutting at monthly intervals,
2. cutting at two months' intervals,
3. cutting at three months' intervals,
4. cutting after four months' growth, followed by an aftermath cut of two months'
growth, and
5. cutting once only towards the end of the growing season, usually a six-monthly
cut.
To test the digestibility, nine trials were conducted on three adult Merino Wethers.
Six-monthly and four-monthly cuttings yielded more dry matter than two and three-
monthly cuttings. Monthly cuttings produced the lowest dry matter. Furthermore,
the amount of dry matter obtainable under a two-months' system of cutting may not
differ materially from that of one cut at the end of the season or two cuts as represented
by a four-monthly cut followed by an aftermath cut two months later.
Phosphorus, potassium and chlorine, crude protein, and silica free ash contents,
decreased with the decreasing frequency of cutting. Calcium and magnesium contents
did not show appreciable variations with stage of growth. Sodium content decreased
with age in the plant. Crude fibre content varied inversely with the crude protein
content. Nitrogen-free extract content varied very little and showed no definite
tendency. Ether soluble extract content indicated irregular fluctuations. The highest
yield of crude protein and phosphorus was obtained when grasses were cut at intervals
of two months during the growing season.
The digestion coefficients for crude protein, crude fibre, nitrogen-free extract, and
to a lesser extent, ether extract decreased with the decreasing frequency of cutting. The
apparent digestibility of the crude protein appeared to be influenced to a greater extent
than the other constituents.
The nutritive ratio remained extremely wide in most cases but was profoundly in-
fluenced by the stages of growth. During 1935-36 it decreased from 18.6 to the medium
value of 7.8 in the monthly cuts, while in 1936-37 it remained wide for all treatments
but nevertheless decreased from 29.6 in the oldest to 10.6 in the youngest herbage.
It is concluded that a system of cutting natural veld grasses at intervals of two
months during the growing season will result in the optimum utilization of such pastures.
(S. A. Q.)
ORIGINAL ARTICLES
CONTAGIOUS PLEURO-PNEUMONIA OF GOATS
BY
E. O. LONGLEY, B.Sc., M.R.C.V.S.
Lecturer in Pathology and Bacteriology, Madras Veterinary College
(With Plates V to XV and two text-figures)
(Received for publication on 27th February 1940)
INTRODUCTION
A. Historical and geographical aspects
H UTYRA and Marek [1938] assign one and a half pages of their fourth edi-
tion to caprine contagious pleuro-pneumonia, which they describe as a
pneumonia of lobar distribution with, commonly, sero-fibrinous pleuritis and
profuse effusion. Splenomegaly and petechial haemorrhages on the serous
and mucous surfaces, are also described. According to them the disease
was first described in Algeria by Thomas in 1873 and has since been reported
from the Pyrenees in Germany, in Italy, in the eastern European countries
and also in East Africa and India, in most instances in epizootic form. Orr
[1937] gives a description of a condition of goats in the Malay States which
closely accords with that occurring in the Madras Province.
The existence of a pneumonic disease of goats in epizootic form in India
was first recognised some 20 years ago, and quoting Shirlaw [1939] : ' Inten-
sive research on this problem dates from 1919. Between the years 1919-23,
Muktesar was approached by the Provinces of Bombay (including Sind),
Punjab and N.-W. F. Province and the United Provinces for help in the
elucidation and control of goat and sheep diseases. Pneumonia of rather a
peculiar type was stated to be the most serious problem affecting breeders
and was said to occur most severely in the sub-montane tracts, although not
confined to them. In 1923, the disease reached such dimensions in Garhwal
(U. P.) as practically to exterminate certain herds, and losses were generally
so great that goats had to be imported from China.' It thus appears that
this disease is wide-spread, occurring in Europe, the near East and East
and can assume panzootic proportions.
Sporadic research had proceeded at the Madras College from the year
1932, with a view to transmitting the disease, using material preserved in
glycerine and saline received from field outbreaks, but no consistent results
attended the work either in Madras, or elsewhere. In 1937, a scheme for
intensive research was drawn up and a Government grant obtained for its
execution.
Before proceeding to the experimental work, it is proposed to describe
briefly the clinical picture, course, and post mortem appearances in the specific
condition.
( 127 )
128
Contagious Pleuro-Pneumonia of Goats
B. Symptomatology, course and pathology
Symptoms.—These are quite commonly not well marked and naturally
vary with the stage of the disease. Copious nasal discharge is commonly
described. This is almost always attributable to heavy infestation with the
larvae of Oestrus ovis, which have been present in over 60 per cent of all goats
examined, numbering as many as 15 larvae per capitum. The nasal discharge
and the pneumonia are probably independent of each other. In all experi-
mentally induced pneumonias, the presence of a nasal discharge has been
quite exceptional. Nor is coughing by any means a constant feature. In
many cases with even advanced lesions no cough is evident and in some cases
coughing has been observed with no pneumonic lesions at autopsy. In
most instances the disease has been afebrile. It is noteworthy however, that
a transient rise of temperature, previously normal, to 104°-105°F., is by no
means rare, often occurring on the day of, or a day or two preceding death.
This is particularly true with the experimental passages and the type of curve
is shown in Charts I and II.
Chart I
E. O. LONGLEY 129
Chart II
It is characteristic of the Indian goat that the appetite is unimpaired
and the animals usually take food readily up to the agonal stage.
Constant symptoms are loss of condition, weakness and staring coat,
while in the experimental pneumonias, sudden dullness and listlessness is a
common and valuable sign. Dyspnoea is sometimes marked, particularly
on exertion and in the latest stages, when the bleat also becomes weak and
assumes a peculiar timbre.
Percussion gives a definite indication in advance cases, particularly if
the pneumonia is unilateral, but if the lesions are early or involve the apical
lobe only, presents obvious difficulties and cannot detect specific from non-
specific consolidation.
Summarising, it may be stated that no pathognomonic symptoms can
be described and that diagnosis by clinical inspection of individuals is by
no means easy.
Course.—With the onset of recognisable symptoms, if any, the course is
rapid and death occurs usually within a week. In any case death is sudden,
the animal being found dead in the morning, or suddenly collapsing during
the day and expiring in a matter of an hour or so. On the basis of experi-
mental transmission, the incubation period is 8—28 days, usually 12—15 days.
130
Contagious Pleuro-Pneumonia of Goats
In healthy goats insufflated experimentally for purposes of passage, (108) 81,
or 75.0 per cent have been infected. Including with these all healthy con-
trols to experiments, 104 out of 139 or 74.8 per cent developed the disease.
Pathology.—The post mortem appearance is very characteristic and when
a few cases have been seen is unmistakably recognisable.
Pleurae.—The visceral pleura over a pneumonic lesion is constantly
involved. Pleuritis is usually present on the costal pleura, but is very vari-
able in extent. In early cases, a small focus of dry pleurisy will be evident
and well marked congestion of the capillaries, which stand out in a clear net-
work, is invariably present. This latter phenomenon is also a feature of
the local reaction in the subcutis, as described later. All degrees from this
to involvement of the entire pleural surface may be present. Where the
lesions are extensive, there is generally effusion, which is invariably serous or
sero-fibrinous, never purulent or haemorrhagic. If liquid, coagulation of the
effusion constantly occurs within five minutes of opening the thorax.
Table I indicates the incidence of pleuritis, and the occurrence and volume
of the effusion in a series of 54 cases of the specific experimental and natural
pneumonias.
TABLE I
c.c.
0
14
25
5
50
8
100
7
150
1
200
2
250
2
300
4
Total cases
43
As shown, 43 or 80 per cent of the 54 cases manifested pleuritis, 24 with
50 c.c. or more of effusion. In four instances as much as 300 c.c. was present.
In a few cases, early fibrosis, with the formation of adhesions between the
viceral and parietal pleurae, has been found at autopsy.
Lungs.—The tables below record the sites of the lesions in the same
series of 54 specific pneumonias. Table II records the incidence of unilateral
and bilateral involvement, Table III, the particular lobes involved.
TABLE II
Lung involvement
Unilateral
Left
5
Right
13
18
Bilateral
Left
15*
Right
8*
36
* These figures represent markedly more advanced lesions in the lung indicated.
In the balance of 13 cases the right and left lungs were equally involved.
Ind. J. Vet. Sci. & Anim. Husb., Vol. X, Part
II
]
PLATE V
FIG. 1.
FIG. 2.
Typical post-mortem appearance of affected lungs. The right hand arrow indicates.
E. O. LONGLEY
131
TABLE III
Lobar distribution*
Apical
34
Cardiac
42
Diaphragmatic
56
All three
12
It will be seen (Table II) that bilateral involvement is twice as common
as unilateral, though usually the lesions are not equally extensive on the two
sides. The apparent predilection for the right lung in unilateral involve-
ment (q. v.) is off-set by the asterisked figures for bilateral involvement, where
the more advanced lesions were predominantly on the left side. Thus the
totals for the two sides are : left lung 20, right lung 21.
Table III indicates that the diaphragmatic lobe is the most frequently
affected (63.0 per cent) the apical the least (42.5 per cent), with the cardiac
lobe intermediate (50.0 per cent). This is not in accordance with Orr (op. cit.)
who reports the most advanced and presumably most frequent lesions in the
apical lobe.
Entire lungs have been involved in 12 of the 54 cases concerned.
Lungs.—Some 40 natural, and nearly 300 experimental cases of the
pneumonia have been observed post mortem during this study. There are
no distinguishing features between the two. It may be stated here that
in no single instance of the pneumonia have parasites been detectable in the
lesions, though search was made over scores of cases ; and no known orga-
nisms have ever been either isolated from, or observed in, the fresh, specific
lesions.
Plate† V, figs. 1 and 2 depict the typical appearance at autopsy. In
fig. 1 the goat is on its back and the left thoracic wall has been reflected
forwards as described later, exposing the diaphragm, lungs, and part of the
pericardium in situ. The pneumonia was bilateral, and in fig. 2 the right
lung is also shown. In the following description frequent reference will be
made to this plate.
Two types of early lesion have been recognised, the focal and the diffuse,
these differing materially from each other.
The focal lesion—less common than the diffuse—may be single but
is quite commonly multiple, and consists of a small zone of hepatisation
about 1 cm. in diameter, yellowish-grey in colour, slightly raised and clearly
demarcated from the surrounding healthy lung tissue. A narrow peripheral
zone, light grey in colour, surrounds the lesion, and is undoubtedly the ' zone
of spread '. In figure 2, a typical such lesion is present on the diaphrag-
matic lobe of the right lung, as indicated by the arrow.
The diffuse lesion is peculiar and highly characteristic, almost invariably
involves the apical or cardiac lobes in part or entirely, and is a frank oedema
* One or both lungs, individual lobes considered separately.
† The photographic plates throughout this paper are untouched.
B
E. O. LONGLEY 133
been present in only one instance. The petechial haemorrhages described
by Hutyra and Marek have never been observed and it is not unlikely that
such have been cases of haemorrhagic septicaemia, not of the specific pneu-
monia.
No lesions other than those in the thorax are present, and no parenchy-
matous changes are found in the susceptible organs.
Pericarditis as a complication
One case of sero-fibrinous pericarditis, indistinguishable in character
from the typical serosal involvement in the specific pleurisy, has been observed.
The goat in question, No. 298, died 13 days p. ins. with an experimental pneu-
monia involving the cardiac lobe of the right lung and a severe pleurisy with
coagulated effusion covering most of the lung. The pericardium was much
thickened, oedematous and contained a considerable quantity of coagulated
effusion. The myocardium was unaffected, but there was marked oedema
over the coronary grooves. In two other cases, very oedematous thicken-
ing of the epicardium has been observed, but with no evident involvement
of the serosal surfaces, or abnormal effusion. Pericardial involvement is also
recorded as a complication in the bovine disease.
The histo-pathology of the lesions is described separately.
EXPERIMENTAL WORK
A. Technique
Donors.—In view of the suspicion of a virus etiology and the lack of
success that had attended the previous attempts at transmission with materials
sent to the laboratory, perhaps attributable to the death of the infective
agent in transit, it was decided to obtain a supply of live affected goats on
the premises and slaughter these as required, to provide fresh material.
Though this procedure solved the problem of transmission, it temporarily
created its own problem, as donor goats were not always available for material,
and in one instance, when a six weeks lapse in their supply was experienced,
we suffered the loss of several experiments. With the possibility of artificially
induced pneumonias, however, this difficulty was eliminated.
Control of accidental infection.—In view of the reported high infectivity
of the disease, attempts were made in the initial experiments to effect rigid
isolation of all experimental groups one from another, and to place all goats
in quarantine for not less than a month before inoculation.
The premises and staff provision, however, did not lend themselves to
any effective isolation of this kind and the early experimental finding that
infection was very rare and uncertain by even the closest contact (Experi-
ments 16 and 17) resulted in all such precautions being abandoned,
except in the case of the first two pulmonary transmissions by insufflation
(Experiments 11 and 12), where rigorous isolation was practised.
Quarantine.—For practical considerations, the quarantine had also to
be dropped. The deciding factor in abolishing quarantine was, however,
E. O. LONGLEY 135
Parasites.—Bearing in mind the remote possibility of invertebrate vec-
tors, unless the pressure of work was preclusive a search was always made
at autopsies for ecto-and endo-parasites, which have been submitted to the
Parasitology Department for identification. The results in condensed form
are given in the Appendix.
B. Experimental transmission
(I) By inoculation
Experiment 1.—Attempted transmission from pulmonary lesions
Inoculum..—18 goats were used. The inoculum for the 12 goats of the
experimental group was an emulsion of the pulmonary lesions from one of the
first four goats received through the Veterinary Investigation Officer as
suspected cases. The six control goats received emulsion of healthy lung.
For this experiment only, the emulsions were prepared with pestle and mortar,
and bacterial contamination was inevitable (the air in the laboratory has been
found to account for one colony per 2.5 seconds on an exposed 10 cm. plate).
The atypical and localised lesions described below are probably attributable
to this.
Donors.—All four donor goats had symptoms of pneumonia. All at
autopsy were found to have localised and chronic pneumonias, with little
or no effusion, and in one case (goat No. 4), numerous small abscesses in the
lung and mediastinal glands, from which a staphylococcus was isolated.
In the other three, bacteriological examination, microscopical and cultural,
was negative. Histologically, the lungs presented a picture of a chronic
interstitial pneumonia, but neither parasites nor eosinophilia were evident.
Procedure.—The inoculum was prepared from goat No. 3. The scheme
of the experiment was to inoculate pairs of goats by the intra-venous, intra-
tracheal and intra-thoracic routes, alone and in combinations, as shown in
Table IV.
TABLE IV
First injection
Second injection
Experimental
group
P. L. E.*
Control group healthy
L. E.
I/V
..
2
2
I/Tr.
2
..
I/Thor.
2
..
I/Tr.
..
2
2
I/Thor.
2
..
I/Thor.
2
2
Total
12 goats
6 goats
* P. L. E. —Pneumonic lung emulsion plus any effusion.
E. O. LONGLEY 137
registered 105°F., and it was decided to slaughter it for transmission purposes
that day. At autopsy, the typical pleuro-pneumonia was found with complete
consolidation of the right diaphragmatic lobe, and partial consolidation of the
apical lobe, and of the left diaphragmatic lobe. Bilateral pleuritis with 30
c.c. of serous effusion was also present.
The inoculum was prepared as described.
As controls, a group of four goats was given the same dosage by the same
routes of the pneumonic lung emulsion after heating it at 55°-60°C. for 40
minutes, this procedure providing a proper control, and simultaneously a test
of the thermostability of any infective agent. Moreover, it promised a pre-
liminary test at a later date of any antigenic properties of a ' heated vaccine '.
Owing to the previous experience with intra-venous injections, it was
decided to use a 1 : 3 emulsion well diluted in saline, to inject slowly, and to
increase the dosage to the maximum that could be tolerated.
Procedure.—The pneumonic lung emulsion was administered intra-
venously to the first two goats in 1 c.c. doses diluted in 4 c.c. of saline. As
this was without effect, the next pair received 2.5 c.c. in 2.5 c.c. of saline,
without harm. The last pair then received 5 c.c. in 5 c.c. saline. Both
evidenced shock, one slight the other very profound, leading to its death
over-night.
Of the control group the first couple received the same minimum dose
(1 c.c.) of the heated emulsion in 4 c.c. of saline. Both evidenced shock.
The second pair received 2.5 c.c. in 2.5 c.c. of saline. Both were profoundly
shocked, and one died within a few minutes of the injection. It was replaced
by a fifth goat which survived this dosage. The emulsions were then ad-
ministered by the other routes as shown below.
TABLE V
A.
Experimental
Group.
Unheated
P. L. E ex-
Donor 13.
„
„
B
Control Group
Heated
P. L. E. ex-
Donor 13
„
Goat
No.
33 }
34
39 }
40
*31}
32
37 }
38
35 }
41
Date
9-12-38
9-12-38
9-12-38
9-12-38
9-12-38
I/V
Emul-
sion
1 c.c.
2.5 c.c.
6 c.c.
1 c.c.
2.5 c.c.
Saline
4 c.c.
2.5 c.c.
5 c.c.
4 c.c.
2.5 c.c.
I/Tr
1 c.c.
1 c.c.
1 c.c.
1 c.c.
1 c.c.
I/M
5 c.c.
5 c.c.
5 c.c.
5 c.c.
5 c.c.
S/C
5 c.c.
5 c.c.
5 c.c.
5 c.c.
5 c.c.
I/N
2 c.c.
2 c.c.
2 c.c.
2 c.c.
2 c.c.
Result
+ + + +
+ + + +
+ + + +
+ + + +
—
+ + + +
—
—
—
—
Remarks
Died
15-12-38
Slaughter-
ed
14-12-38
Died on
14-12-38
Died on
15-12-38
Died on
15-12-38
Survi-
val
days
p. ins.
6
5
5
6
6
* Died on the 10th of December 1938 from shock.
E. O. LONGLEY 139
respectively of the local effusion from this goat survived 21 days and presented
no lesions at autopsy. None of the goats had any pulmonary lesions at their
ultimate autopsy.
(1) Five healthy goats, each injected by various routes with fresh strained
pneumonic lung emulsion, all died within five days with massive oedema and
necrosis of muscle tissue at the sites of both the intra-muscular and the sub¬
cutaneous inoculations.
(2) Four control goats receiving similar doses by the same routes of a
portion of the pneumonic lung emulsion subjected to heat at 55°-60°C. for
40 minutes, showed no reaction.
(3) No pulmonary lesions were present at autopsy in either the experi-
mental or control groups.
(4) The pneumonic lung tissue, pleuritic and pericardial effusion of the
donor goat, and the inocula, proved sterile on both aerobic and anaerobic
culture media, and the pleuritic effusion was negative to biological tests in
guinea-pigs and rabbits.
Discussion and conclusions.—No importance attaches to the isolation of
the few staphylococci from lesions on some media. This is almost certainly
ascribable to air contamination, as in the preceding experiment. No evidence
of anaerobic infection was obtained. The result indicates that a specific
infective thermolabile agent was present in the lung lesions.
Experiment 3.—Attempted passage from the local reactions
The object of this experiment was to effect transmission of the infection
in goats, and confirm or otherwise the absence of pathogenic anaerobes by
biological tests in goats and guinea-pigs.
Procedure.—The emulsion prepared from goat No. 34 was administered
on the day of preparation (14 December 1938) to two experimental goats
and to two control goats, in the latter after heating it at 55°-60°C. for 30
minutes. The dose in each case was 5 c.c. intra-muscularly in the right thigh
and 5 c.c. subcutaneously over the right shoulder.
Each preparation was injected in 1 c.c. doses intra-muscularly to two
guinea-pigs. All the four guinea-pigs survived 21 days, when they were
destroyed and presented no lesions.
Results.—Both experimental goats presented on the day p. i, 15th Decem-
ber 1938, moderate degrees of swelling at both the sites of inoculation. These
did not progress and receded completely by seven days. No thermal reaction
and no systemic disturbance were observed. Neither control goat showed
any reaction whatever.
Summary.—(1) Inoculation, intra-muscular and subcutaneous, of 5 c.c.
of emulsion of muscle together with effusion from the local reaction to the
inoculation of pneumonic lung emulsion, gave rise to transient reactions
only in the two recipient goats.
(2) No reaction was observed in the two recipients of the emulsion
after heating it at 55°-60°C. for 30 minutes.
(3) Two pairs of guinea-pigs inoculated intra-muscularly with the un¬
heated and the heated emulsions were unaffected.
Conclusions.—This experiment satisfactorily confirms the absence of
pathogenic anaerobes in the lesions.