F. C. MINETT
103
ppeared to take place in heart-blood clot and in
one-marrow. In many cases, meat-liver cultures
rown from the final dilution of the series sown
om tissues taken after storage of the carcase
ere identified as those of blackquarter, In
ie local lesion at the time of death, most of the
rganisms have already sporulated. If fresh
xudate, to which citrate has been added, is
cubated under a good vaseline seal for 48 hours-
t 28ºC., multiplication of the blackquarter
rganism may at times be observed.
In the above experiments only one tube of meat-
ver medium was inoculated from each serial
ilution of the tissue but the results were consistent
nd indicated substantial increase in the number
organisms on storage. To give an idea of the
chness in bacteria of tissues and fluids from
aimals dead of blackquarter, it may be said that
rowth in meat-liver medium was commonly
btained from amounts of material as small as
ie following:
resh heart-blood (guinea-pig) .
resh heart-blood (sheep) . .
resh bone-marrow (sheep) . .
resh local lesion exudate (sheep) .
resh muscle lesion (sheep) . .
lood from guinea-pig heart after
storage of carcase for 24 hours at
30ºC .
.
.
.
.
lone-marrow from sheep after
storage of carcase for 48 hours
0.0002 to 0.00005 gm.
0.0002 gm.
0.0002 to 0.00001 gm.
0.000002 gm.
0.0000001 gm.
0.000004 gm.
0.0000002 gm.
The results of a final series of experiments on
one-marrow from sheep carcases are shown in
Table II. In these, five tubes of meat-liver
medium were sown from each serial dilution of
suspension covering the expected end point, 1.0
c.c. amounts being added to the culture tubes,
nd the probable numbers of organisms present
the original tissue suspension being computed
from tables given by Halvorson and Ziegler [1933].
appears that (1) the number of organisms
resent in the bone-marrow at the time of death
aries considerably, (2) of the eleven cases—
xcluding sheep 318, the carcase of which was
kept near freezing point—there was a quite definite
increase in the numbers of organisms after death
in eight cases, a slight increase in one and a reduc-
tion in two. In one of the latter (sheep 116),
not only had the numbers fallen in the bone-marrow
ut no sporulation had occurred. In the sheep
also, where slight increase only had occurred
(No. 307), no sporulation had occurred in the bone-
narrow. This sheep was killed when near death,
Sheep 318 and 336 formed a pair, the carcase of
the first being placed at 35°F. and the latter at
70°F. Air temperatures where not shown were
probably around 60°F. (3) the increase though
definite, varied greatly in extent. In five cases
the increases were from 50- to 230-fold.
An estimate of the number of spores in the muscle
lesion of a freshly-dead sheep gave a figure of
9 millions per gm., undoubtedly an underestimate.
In one case a well-developed muscle 'tumour'
and fluid exuding therefrom were collected
from a freshly-dead sheep and found to weigh
1,254 gm. (muscle 697, exudate 557) a figure which
will perhaps give some idea of the potential
infectivity of such a carcase.
Microscopical
Multiplication of the organism can also be
readily shown by direct count. With two guinea-
pigs dead 24 hours after injection of culture mixed
with calcium chloride, films of bone-marrow were
made immediately after or within 15 minutes after
death from one femur and similar films from the
femur after the carcases had lain for six hours at
90ºF. At the same time, pieces of liver were
transferred to formalin for sections. With the
films, the organisms present in 50 fields at random
were counted and with the sections the numbers
in 100 fields. The results were:
Guinea-pig 1 films . .
Guinea-pig 1 sections .
Guinea-pig 2 films . .
Guinea-pig 2 sections . .
In the fresh tissue 0.4 organ-
isms per field and in the
stored tissue 7.16.
In the fresh tissue 0.003 organ-
isms per field and in the
stored tissue 4.98.
In the fresh tissue 0.78 organ-
isms per field and in the
stored tissue 8.1.
In the fresh tissue 0.072 organ-
isms per field and in the
stored tissue 15.72.
With a sheep, 15 minutes after death from black-
quarter a piece of liver was removed to formalin
and the carcase then stitched up and left for
six hours at 70-80°F., when another piece of liver
was removed. The counts (100 fields) were,
in the fresh tissue, 0.52 organisms per field and
in the stored tissue 9.86.
RATE OF COOLING OF CARCASES
I am unaware of any data on this subject in the
case of animals. Since the rate of cooling may
have a bearing on the multiplication of pathogenic
as well as of putrefactive organisms in the body
after death, some observations were made. Soon
after the animal had expired, a small incision was
made in the abdominal wall near the flank and