NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
138
Contagious Abortion of Cattle, Sheep and Goats
[VOL. XVIII, PART III
It is probable that a further big reservoir is even now developing. The vastly increased buffalo
population in military establishments cannot be given the attention it would receive in normal times.
Moreover, temporary farms are being erected in the unfavourable climates of south and east India.
It is not improbable that Brucellosis will spread among these animals and these may disseminate
disease to other parts of India when dispersed.
FIG. 2. The death rate of Brucella stored at 37°C.
A—over CaCl 2
B—in 80 per cent humidity.
(For table of counts see overleaf).
SEPTEMBER, 1948]
JOHN
B.
POLDING
139
Table of counts for Fig. 2.
0
18
24
26
30
42
46
Hours
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
Count in millions
A. in dry air
6700
990
. .
9
0.58
0.060
. .
B. in humid
air
6700
5800
. .
. .
3800
1280
220
FIG. 3. The death-rate of Brucella (suspended in distilled water) stored at 37ºC.
Graph A—over CaCl 2
Graph B—in 80 per cent humidity.
(For table of counts see overleaf.
D
140
Contagious Abortion of Cattle, Sheep and Goats
[VOL. XVIII, PART III
Table of Counts for fig. 3
0
24
28
30
36
48
60
84
96
Hours
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
Count in millions.
A. dry air.
4800
4000
3700
221
. .
15
. .
. .
5
B. humid air.
4800
2200
. .
1940
1630
700
310
190
38
SECTION IV. THE BACTERIOLOGY OF INDIAN STRAINS
To rehearse the whole bacteriology of Brucellosis, or to cite a torrent of references here, would
be supererogatory and those unfamiliar with its details are referred to the many excellent treatise
in the literature ; in the pages to follow, the subject is dealt with solely in so far as it concerns the
disease in India.
Classification
The bacterial genus Brucella is usually supposed to contain three species Br. abortus, Br. meli-
tensis and Br. suis. Not all strains, however, can be so classified and, in an examination of some
2,000, Huddleson [1939] has mentioned 13 that were atypical. Some eight or ten methods of classify-
ing the genus have been described, but the criteria most commonly used are based on (i) CO 2 require-
ments at isolation (ii) antigenic structure, (iii) H 2 S excretion and (iv) the inhibitory action of dye
media. Because all tests are relative estimations of biological processes and as most are very suscep-
tible to errors of technique and personal judgement, they should be made as far as possible on a
number of strains at the same time and by the same person, using a standard technique and a single
batch of original media.
The techniques used in the present work have been as follows :—
(i) CO 2 requirements at isolation. All sowings for primary isolation of Brucella are incubated
in a partial CO 2 atmosphere (cultures on solid media in 10 per cent and in fluid media 20 per cent
of CO 2 ). At first subculture, all strains isolated, are sown in duplicate on liver agar slants pH 6.8
one slant being incubated in air and one in 10 per cent CO 2 . Strains failing to grow in air are
presumed to be Br. abortus ; strains growing in CO 2 and air are taken as one of the two other
variants.
(ii) H 2 S elimination. When a sufficient number of recently isolated strains have accumulated,
they, together with two strains of each of the three type variants, are sown into slants of tryptose
agar prepared according to the maker's formula (liver agar may be used, but its sulphur content
142
Contagious Abortion of Cattle, Sheep and Goats
[VOL. XVIII, PART III
abortus and the Melitensis, monospecific melitensis serum. Each primary dilution of each mono-
specific serum is then titrated against abortus and melitensis antigens, which are prepared in the
ordinary manner (p. 149). If all has gone well, the monospecific sera should react to between the
fourth and seventh dilution with their homologous antigens, and not at all, or to one or two dilu-
tions only, with their heterologous antigens. In each case the dilution of monospecific serum
which gives the greatest difference of titre between the homologous and heterologous titrations
is selected for use. The series of dilutions used in the final titrations are prepared by doubling
the dilution in each succeeding tube of a series and, assuming the primary dilution of a serum is
1/20, the final titration series would run 1/40, 1/80 and so on. Whilst, if absorption had been
nearly optimum, the serum would react to about +1/640 with its homologous antigen and to
about +1/40 with the heterologous. To differentiate unknown Brucella strains all that is necessary
is to prepare antigens from them (p. 149) and titrate each against monospecific abortus and
melitensis sera. It is to be noted that absorption of Br. suis antiserum is purposeless, as neither
antibody is present in excess of the other. Similarly, if Br. suis antigen, in which neither antigenic
factor is present in excess, be titrated against monospecific sera, equal titrations are likely to
result. The rough or so-called ' para ' strains cannot be classified serologically.
In India, the obtaining of satisfactory specimens for bacterial examination presents many
peculiar difficulties not encountered in temperate climates. The main troubles are the early putre-
scene of dead tissues, dust contamination, long periods of transport in warm environment, but above
all difficulties of communications, for abortions usually occur without notice in remote localities,
which cannot be reached in time by persons qualified and equipped to take samples fit for bacterial
examination. The Brucella strains it has been possible to secure have consequently been disappoint-
ingly few, but, such as they are, their origin and classification are given in Table XXV.
TABLE XXV
Classification of Indian Brucella strains
Locality
Ahmednagar
.
.
.
.
Ambala
.
.
.
.
.
Bombay
.
.
.
.
.
Cuttack
.
.
.
.
.
Ghoom
.
.
.
.
.
Hissar
.
.
.
.
.
Jarsugudda
.
.
.
.
Jubbulpore
.
.
.
.
Kirkee . . . . .
Br. abortus
Host
Farm
cow
1
2
1
0
1
0
0
0
0
Farm
buff.
0
7
2
0
0
0
0
0
1
Horse
1
0
0
0
0
0
0
0
0
Br. melitensis
Host
Farm
cow
0
0
0
0
0
0
0
0
0
Goat
0
0
0
0
0
1
0
0
0
Mare
0
0
0
0
0
0
0
0
0
Unclassified
Host
Farm
cow
0
0
0
0
0
3
0
1
0
Farm
buff.
0
0
0
0
0
0
0
0
0
Village
cow
0
0
1
1
0
0
1
0
0
SEPTEMBER, 1948]
JOHN
B.
POLDING
143
Lacality
Lahore.
.
.
.
.
Lucknow
.
.
.
.
.
Meerut
.
.
.
.
.
Mukteswar
.
.
.
.
Mysore
.
.
.
.
.
Patna . . . . .
Poona
.
.
.
.
.
Raipur (Madras) . . .
Razmak
.
.
.
.
.
Sialkot
.
.
.
.
.
TOTAL .
Br. abortus
Host
Farm
cow
3
0
0
1
1
0
0
0
1
0
11
Farm
buff.
0
0
1
1
0
0
0
0
1
1
14
Horse
0
0
0
0 0
0
0
0
0
0
1
Br. melitensis
Host
Farm
cow
1
0
0
0
0
0
0
0
0
0
1
Goat
0
0
0
0
0
0
0
0
0
0
1
Mare
0
0
0
0
0
0
1
0
0
0
1
Unclassified
Host
Farm
cow
0
1
0
6
0
1
0
0
0
0
12
Farm
buff.
0
0
0
2
0
0
0
0
0
0
2
Village
cow
0
0
0
0
0
0
0
3
0
0
6
Total Br. abortus=26 ; total Br. melitensis=3 ; total unclassified= 20.
Grand total=49 strains
In this classification, all 26 Br. abortus variants fell precisely into their class, with no discre-
pancies. The work was in all cases controlled by parallel tests on (1) European and American abortus.
(2) Maltese melitensis and (3) American suis strains. It is noteworthy that all pure abortus strains
come from organized farms most of which have carried, or still carry, European cross-bred stock,
and they occur equally in cows and buffaloes. As regards the melitensis strains, in all the three,
there was some doubt as to exact classification (Table XXVI).
TABLE XXVI
Classification of Indian melitensis strains
Strain
Abortus control
.
.
.
.
Suis control
.
.
.
.
.
Melitensis control
.
.
.
.
Indian-melitensis—
I
.
.
.
.
.
.
II . . . . . .
III
.
.
.
.
.
.
CO 2
requirements
at
isolation
CO 2 .
air/CO 2 .
air/CO 2 .
air/CO 2 .
air/CO 2 .
air/CO 2 .
Excretion
of H 2 S on
successive
days
+++
+++
++
+
+
+++
+++
+++
+++
+++
++
++
+
Nil
Nil
Nil
Nil
Growth on
thionin
+++
+++
+++
+++
+
fuschin
+++
+
+++
+++
+++
+++
Agglutination against
Mono-A
serum
+++ 1/320
0
+1/20
strain rough,
test not
possible
Do.
++ 1/320
Mono-M
serum
+ 1/20
0
+++ 1/640
. .
. .
++ 1/160
144
Contagious Abortion of Cattle, Sheep and Goats [VOL. XVIII, PART III
It will be observed that the first two strains were rough and, therefore, their antigenic structure
could not be examined, but in all probability they are normal melitensis types. It is alleged that
they were isolated some years ago from a cow and a goat in the Punjab. The third, was isolated
from a naval rating in Poona hospital and, whilst growing in air and CO 2 and falling to produce
H 2 S, it grew but weakly on thionin and its antigenic structure appears to be more A than M. The
origin of these Melitensis strains is obscure, but it seems possible that there is a slight occurrence of
Br. melitensis infection in northern India.
TABLE XXVII
Ambiguous Indian Brucella strains
Strain's origin
Lucknow
.
.
.
.
.
Jubbulpore
.
.
.
.
.
Hissar
.
.
.
.
.
Mukteswar
.
.
.
.
.
Mukteswar
.
.
.
.
.
Kanara District, Bombay (village).
Orissa (village) . . . . .
Madras (village) . . . . .
Bihar
.
.
.
.
.
CO 2
requirements
at
isolation
CO 2 . .
CO 2 . .
CO 2 . .
CO 2 . .
CO 2 /air .
CO 2 .
. .
CO 2 . .
CO 2 /air .
H 2 S
excretion
+++
++
++
+
+++
++
+
+
+++
++
+
+
+++
++
+
+
+++
++
++
+++
++
+
+
++
+++
+++
+
+++
+++
++
+
+++
+++
++
++
+
Growth on
thionin
+++
+++
+++
+++
+++
+++
+++
+++
++
fuschin
+++
+++
+++
+++
+++
+++
+++
+++
++
Agglutination against
mono-A
serum
1/100
Negative
1/1280
1/640
1/320
1/160
1/320
1/320
1/320
mono-M
serum
1/5120
1/3560
1/80
1/80
1/80
Negative
1/80
1/80
1/40
Pulses are used as an aid to glance estimation of degrees of reaction which are purely comparative. In the H 2 S column
the reaction has been registered for five successive days.
SEPTEMBER, 1948]
JOHN
B.
POLDING
147
TABLE XXIX
The virulence of Indian field strains
Strain
F.46 Indian CO 2 A/M . . .
F.45 Indian CO 2 A . . .
F.41 A Indian CO 2 A/M . .
F.40 Indian CO 2 A/M . . .
F. 36 Indian CO 2 A/M . . .
F.34 Indian M
.
.
.
.
A.1 European A . . . .
M. 1. Malta M.
.
.
.
.
V.1 [Cotton's 19]
.
.
.
.
V.4 [McEwens 45(6)] . . .
V.5 [McEwens 45(20)] . . .
Doses of bacteria
16×10 9
..
..
..
..
..
..
..
..
5
2
5
8×10 9
..
..
..
..
..
..
..
..
4
1
5
4×10 9
4
4
5
5
5
5
3
5
1
1
2
2×10 9
3
2
5
3
4
5
1
3
..
..
..
1×10 9
2
0
2
0
4
4
0
1
..
..
..
0.5×10 9
3
1
2
1
1
4
1
1
..
..
..
Numbers=dead mice out of 5.
A=Br. abortus M=Br. melitensis A/M=Br. abortus/melitensis CO 2 =CO 2 sensitive.
The Indian strains that were typed were recently isolated and, except the melitensis variant,
were CO 2 sensitive ; as might be expected the order of virulence proved to be as follows : melitensis
most virulent; abortus/melitensis of intermediate virulence and abortus least virulent. As repeated
subculturing is supposed to lead to loss of virulence, a comparison with the overseas type-specific
strains must be undertaken with caution, in as much as the Maltese strain has been isolated for six
years and the English abortus strain must be many years old. If, however, due allowance is made
for this, the experiment suggests there is little difference between Indian and overseas variants. In
order to check this suggestion, in Table XXX the Indian strains are compared with an average
result of four recently isolated English Br. abortus strains typed by Priestley [1938] and, if it is to be
believed that tests done by different persons can be at all comparable, the foregoing conception of
virulence seems to be substantiated.
TABLE XXX
Comparison of the virulence of Indian and European strains
Strains
Indian M
.
.
.
.
.
.
.
.
.
.
Indian CO 2 A/M*
.
.
.
.
.
.
.
.
Indian CO 2 A
.
.
.
.
.
.
.
.
.
McEwens CO 2 A† . . . . . . . .
Bacterial dose
4×10 2
5
5
4
4
2×10 9
5
4
2
2
1×10 9
4
2
0
1
0.5×10 9
4
1
1
0
Numbers= dead mice out of 5.
*Average of 3 Indian village A/M strains.
† Average of 4 of McEwen's abortus strains (CO 2 sensitive and virulent) taken from J. Com. Path. 51, 284.
A=Br. abortus M=Br. melitensis A/M=Br. abortus/melitensis CO 2 =CO 2 sensitive.
E
150
Contagious Abortion of Cattle, Sheep and Goats
[VOL. XVIII, PART III,
TABLE XXXI—contd.
Time
Density of antigen*
5
>4
<4
3
2
<2
1
<1
½
<½
Serum (2) Stableforth's reconstructed serum, diluted 1/400 (titre +1/1280).
11.15 A.M. . .
11.25 A.M. . .
11.35 A.M. . .
11.40 A.M. . .
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
+
+
+
+
—
±
+
+
—
±
±
±
—
—
—
±
—
—
—
—
Optimum primary dilution of antigen= between 2 & 1 on Brown's scale.
Serum (3) Rabbit serum, diluted 1/640 (titre ++1/640).
11.40 A.M. . .
11.55 A.M. . .
12.25 P.M. . .
12.50 P.M. . .
1.5 P.M. . .
After 20 hours bench
temperature.
—
—
—
—
—
±
—
—
—
—
—
±
—
—
—
—
—
±
—
—
—
—
±
+
—
—
—
±
+
++
—
±
±
+
+
+++
±
±
±
+
+
+++
±
±
±
+
+
+++
—
±
±
+
+
+++
—
—
±
±
±
+++
Optimum primary dilution of antigen=less than 1 on Brown's scale.
Serum (4) Same as serum (3), diluted 1/10 (titre ++1/640).
11.15 A.M. .
11.20 A.M. . .
11.25 A.M. . .
+
++
+++
+
++
++
±
+
++
±
+
+
±
±
+
—
±
+
—
—
±
—
—
±
—
—
—
—
—
—
Optimum primary dilution of antigen= 5 or more on Brown's scale.
Serum (5) Rabbit serum, diluted 1/2.5 (titre +1/10).
10.50 A.M. . .
10.55 A.M. . .
11.0 A.M.
. .
11.7 A.M.
. .
11.45 A.M. . .
—
—
—
—
+
—
—
±
±
++
—
—
±
+
++
—
±
+
+
+++
±
+
+
+
+++
—
—
—
±
++
—
—
±
±
++
—
—
—
—
±
—
—
—
—
—
—
—
—
—
—
Optimum primary dilution of antigen= between 3 & 2 on Brown's scale.
Serum (6) Same as serum (5), dilute 1/5 (titre +1/10).
11.7 A.M.
. .
11.15 A.M. . .
11.25 A.M. . .
11.35 A.M. . .
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
±
±
—
±
+
++
±
±
+
+
±
±
+
+
—
—
—
—
—
—
—
—
Optimum primary dilution of antigen= about 1 Brown's scale.
* Density of antigen is indicated by the figures in the heads to the columns which correspond to the tube numbers of the Burroughs
Welcome Brown's seale. This density does not take into account the addition of serum, so in the final agglutinating system this density
is halved.
160
Contagious Abortion of Cattle, Sheep and Goats
[VOL. XVIII, PART III
strain was of the abortus type and smooth, while the second sub-culture from isolation was used.
In each case the dose administered was 4000 × 10 6 organisms in 1.0 c.c. of saline, given subcutaneously.
The recipients were grouped as shown in Table XXXV.
TABLE XXXIV
Result tests I and II
Strain No.
Cottons 19
.
.
.
.
.
Huddleson 805
.
.
.
.
Route of
injection
I/P
S/C
I/P
S/C
Guinea
pig No.
95
97
106
115
Serum response at intervals after injection
10 days
+ 1/1280
++1/320
++1/640
+ 1/320
28 days
++1/640
++1/320
+ + 1/40
+ + 1/80
35 days
++1/320
+1/160
+ + 1/40
+ 1/80
TABLE XXXV
Grouping of goats in test III
Strain injected
Indian field strain, group F-6
.
.
.
.
.
.
Cotton's No. 19, group A-4
.
.
.
.
.
.
Huddloson's No. 805, group A-5
.
.
.
.
.
.
Goat No.
72
162
26
188
433
119
64
21
431
Sexual phase
non-pregnant .
pregnant . .
pregnan . .
pregnant . .
pregnant . .
pregnant . .
pregnant . .
pregnant . .
pregnant . .
Age of goat in
months
12
33
60
14
36
48
12
24
60
The mean serum response of the three animals in each group was estimated from a series of tests
with the results shown in Table XXXVI.
TABLE XXXVI
The serum response of goats in test III
Field
strain
Cotton 19
Huddleson
Nil
Nil
Nil
4
+1/160
+ 1/160
+ + + 1/40
6
+ 1/320
+ 1/320
+1/160
9
++1/2560
+1/320
+ 1/640
11
+++1/2560
+1/2560
+ 1/320
18
+ 1/1280
+1/640
+1/80
30
++1/640
+1/320
+ 1/40
45
+++1/640
++1/320
+ 1/40
70
++1/640
+ 1/80
+++1/10
SEPTEMBER 1948]
JOHN
B.
POLDING
161
The response at the field-strain was normal and persistent; that to Cotton's 19 more transient
and that to Huddleson's 805 quite transient. The blood of these goats was cultured at various
intervals (Table XXXVII) and it was found that the virulent strain produced a bacteraemia in all
three of its recepients, whereas no bacteraemia was demonstrable in members of either group
receiving the vaccine strain.
TABLE XXXVII
Haemoculture of goats of test III
Goat No.
72
162
26
188
433
119
64
21
431
F.6
A.4
A.5
6
1
—
—
—
—
C
—
—
C
C
2
+
—
—
—
C
C
—
C
C
3
+
—
—
—
C
C
—
C
C
9
1
C
C
—
—
C
—
C
C
—
2
C
C
—
—
—
—
—
—
—
3
C
C
+
—
C
C
—
—
—
11
1
+
+
+
C
—
—
—
—
C
2
+
C
+
C
—
—
—
—
C
3
C
—
—
C
—
—
—
—
C
15
1
+
—
+
—
—
—
—
—
—
2
+
+
+
—
—
—
—
—
—
3
+
+
C
C
C
—
—
—
—
19
1
—
—
+
—
—
— C
—
—
2
+
—
3
+
—
Tube broken
—
C
—
—
C
—
—
—
C
C
—
—
+ = Brucella isolated from plate,
— = Sterile plate.
C = Contaminated plate.
The blood culture from each date was plated thrice at the end of the first, second and third weeks of incubation.
Sub-heads 1, 2 and 3 refer to these plates.
The birth secretions of all animals were cultured (goat No. 72 became pregnant during the ex-
periment) and abortions were recorded (Table XXXVIII). The results showed that the virulent
strain caused abortion in two out of three goats and general genital infection in all. All the recipients
of the vaccine strains, on the other hand, carried their kids to full-term and appeared to be free from
genital infection.
Test IV. The pathogenicity of Cotton's strain 19 was compared with that of Indian-field-strains
in guinea-pigs. Saline suspensions of Cotton's 19 and Indian-field-strain F. 33 were made in concen-
trations of 10,000, 1,000 and 100 million organisms per 1.0 c.c. Pairs of guinea-pigs were subcutaneously
vaccinated with 1.0 c.c. of these doses. Eighteen days after these inoculations, blood cultures were
prepared from all animals ; all cultures from the guinea-pigs receiving the vaccine strain irrespective
of dosage were sterile, but Brucella organisms were recovered from one guinea-pig, receiving 10,000
million, and from another receiving 100 million virulent organisms. The virulent strain was, there-
fore, capable of producing a bacteraemia on the 18th day even in the smallest dose, while the vaccine
strain did not. One guinea-pig receiving 100,000 million Cotton's 19 organisms died during the
procedure of blood collection, and plate cultures of its liver and spleen produced one, and five, Bru-
cella colonies respectively on each culture—a culture from its kidney was sterile. It appears, there-
fore, that some generalized infection must have been caused by Cotton's 19 at the 18th day. The
remaining animals were killed on the 31st day after injection and their livers, spleens and kidneys
plated. No Brucella colonies were found on the plates from the animals receiving Cotton's strain,
which had evidently thrown off any infection that might have been present on the 18th. day, whilst,
with the exception of one animal (the kidney of which was negative), all receipients of the virulents
strain gave numerous, colonies from all sources of seeding.
162
Contagious Abortion of Cattle, Sheep and Goats
[VOL. XVIII, PART III
Test V. The effect of varying doses of Cotton's strain 19 was tested in crossbred calves, aged
4-8 months. Inoculations were given subcutaneously to pairs of calves, in doses of 800, 4,000, 8,000
and 40,000 million organisms, in saline. The resultant temperature reactions appeared to be un-
affected by the magnitude of the dose, all of them reaching a peak of about 104° to 105° F on the
second day, after which, they fell rapidly to normal. A hard and fairly painful swelling reaching
a maximum on the third day and disappearing in about a week developed at the site of injection.
The animals continued to feed and appeared otherwise unaffected by the injection. All calves res-
ponded with a high serum reaction which peaked about the 12th day with titres in the order of
+/—1/2560. Blood cultures prepared on the 9th, 12th, 15th, 18th and 22nd day after injection
were all sterile. The gradation of doses had no obvious effect on any of their reactions.
TABLE XXXVIII
The results of parturition of the goat of test III
Goat No.
Group F.6—
72 . .
162 . .
26 . .
Group A.4—
188 . .
433 . .
119 . .
Group A.5 —
64 . .
21 . .
431 . .
Date of kidding and remarks
Aborted one male kid, 20th December 1940 . . .
Kidded one full term live kid, 25th June 1940 .
Kidded two dead premature kids, 27th June 1940 .
Kidded one healthy kid, 4th October 1940 . . .
Kidded one healthy kid, 4th October 1940 . . .
Kidded two full term live kids, 27th June 1940 . .
Kidded one healthy kid, 30th October 1940 . . .
Kidded one healthy kid, 15th August 1940 . . .
Kidded one healthy kid, 6th October 1940 . . .
Results of culture of
Placenta
+
+
+
Lost
—
—
—
—
—
Foetus
+
0
+
0
0
0
0
0
0
Milk
—
—
0
—
—
—
—
—
—
Vaginal
swabs
+
+
+
—
—
—
—
—
—
+ = Brucella isolated ; — = Brucella not isolated : 0 = culture. Negative plates were made on six occasions,
on milk and swab-culture.
Test VI. The avirulence of vaccine strains Cotton's 19 and McEwen's 45(6) and 45(20) was
compared with each other and with a selection of virulent strains, by means of toxicity tests in white¬
mice. The result of this work appears in Table XXIX, p. 147. In another experiment of the same
kind Huddleson's 805 was compared with Cotton's 19. According to the criterion of these tests
the descending order of virulence of all strains examined appears to be (1) all field strains, (2)
McEwen's 45(20), (3) Cotton's 19 (4), McEwen's 45(6) and (5), Huddleson's 805 and such information
as can be obtained from the literature confirms these findings.
The criteria of these tests have differed, but all results show that the vaccine strains are, to a
varying degree, less virulent than Indian-field or type-specific strains, while Test III clearly illus-
tates the inability of strains 19 and 805 to produce generalization or abortion, at least in goats.
Indeed, the sum of the experimental evidence suggests that all five strains are safe to use and that
164
Contagious Abortion of Cattle, Sheep and Goats
[VOL. XVIII, PART III,
TABLE XXXIX
The survival of Brucella in saline suspension at various temperatures
Time in days
5
9
12
18
Storage at 0—5°C.
16,000
16,000
..
650
Storage at 20—25°C.
3,400
5,000
..
192
Storage at 37°C.
2,000
1,500
500
40
Figures = Count in millions per c.c.
Tachniqne = Standard count on tryptose agar.
Culture= Cotton's 19. 48 hrs. old.
Vehicle= Saline 0.85 per cent pH unknown.
Density = Brown's scale 9-10.
TABLE XL
The survival of Brucella in saline suspension after transit
Time in days
0
10
15
19
23
Stored at Mukteswar at
79°F.
6700
2640
1180
1080
240
Sent to Lahore and stored
at room temperature
average=71°F. then returned
6700
..
2.5
2.5
Contaminated
Sent
to Lahore and
stored at pit temperature
average = 77°F., then
returned
6700
..
82
2.6
2.6
Figures = Brucella count in millions per c.c.
Bacterial suspension = Cotton's 19, 48 hours old growth in 0.85 per cent saline at a density of Brown's scale 5-6.
TABLE XLI
The survival of Brucella in various fluid vehicles
Time in days
0
5
19
25
40
Saline
8500
10.5
10.8
14.8
3.6
Saline
+2.5 per cent
gelatine
7800
18.0
11.3
8.5
4.0
Saline
+0.5 per cent
glycerine
8500
15.0
Contaminated
..
..
Saline
+0.1 per cent
tryptose
8700
18.0
10.2
3.6
5.6
Figures = Brucella count, in millions per c.c.
Culture = Cottons's 19, 48 hours incumbation.
Vehicles = as shown in table.
Brown's scale = 5-6.
Technique = Standard count.
Medium = Tryptose.
Storage = 42ºC.