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not concerned in the dissemination of the tuberculous virus.

In cases where the systemic blood has become the carrier of
the virus, we characterize this condition as generalized or general
tuberculosis (Weigert). This distinction is of the greatest impor-
tance for meat inspection, since tubercle bacilli gain entrance into>
the musculature, " the meat of traffic," only by the aid of the circu-
lating blood. The musculature, therefore, can be considered as
infected and injurious to health only when the organisms of tuber-
culosis are distributed through the body by means of the blood
(Johne). Tuberculosis of domesticated animals has a pronounced
tendency to localization. This phenomenon may be explained most
simply by the assumption of a prompt filtering action of the lymph-
atic glands as well as by the fact that the tuberculous products in
domesticated animals are, as a rule, poor in bacilli. As asserted by
Johne, however, and confirmed by the experiments of Nocard (see
page 640), individual bacilli which accidentally escape the protective
filtering action of the lymph glands, become inactive in the circu-
lating blood.

The generalization of tuberculosis arises in consequence of the
penetration of numerous bacilli into the systemic circulation. This
may occur in veins affected with tuberculous processes or in tuber-
culous lymphatic glands; in the latter case, with the aid of the
thoracic duct or the right tracheal duct. " Flooding " of the blood
with tubercle bacilli is, according to Weigert, always to be ascribed
to tuberculous affection of the wall of a blood vessel, or thoracic
duct.

General tuberculosis appears in two principal forms : A slight
infection of the blood leads to the formation of isolated tubercles in
various organs ; an extensive infection, to the eruption of innumer-
able tubercles in the majority of the organs. In the first case the
small tubercles commonly grow to become large tubercles or case-
ous foci by peripheral expansion, since in such cases infection of the
blood scarcely appears clinically and, therefore, in and of itself^
gives no occasion for slaughter (chronic general tuberculosis). In
the latter case, on the other hand, tubercles are often observed in a
but slightly altered condition, since this form of generalization, as a^



622 INFECTIOUS DISEASES

rule, gives cause for slaughter (acute miliary tuberculosis). If a
slight infection of the systemic blood has preceded the extensive
Invasion of the tubercle bacilli, we have both processes simulta-
#eously. Weigert characterizes this condition as a " transition
form."

The Participation of Individual Organs in the Eruption of
Tubercles in Cases of Generalized Tuberculosis. After the entrance of
tubercle bacilli into the circulating blood, tuberculous alterations
do not, by any means, occur in all organs in food animals. One
observes, on the contrary, that certain organs are constantly
affected, others rarely, and some almost never. This peculiar
behavior is partly explained by the peculiar connection of the indi-
vidual organs with the blood circulation and by the rapidity of the
circulation in them ; in part, also by the presence of specific sub-
stances ; for example, secretions which influence the development of
the tubercle bacilli in different ways. For other organs we must
assume a resisting power in the tissue itself, against tuberculosis.
Thus, Ziegler characterizes the musculature as " almost immune "
to tuberculosis. The connection with the blood circulation is of
considerable importance, since this determines the quantity of the
bacilli which may find their way into the organ. The lungs, for
example, in cases where the blood is infected through the agency
pf the thoracic duct, receive blood which contains many more bacilli
than all the other organs together, for all of the infected blood cir-
culates through the lungs and thereby large quantities of bacilli
may be removed from the blood by becoming lodged in the
pulmonary capillaries. A similar condition may exist in the liver
if infection is brought about by entrance of the bacilli into a branch
of the portal vein. In fact, in this case the filtration of the blood
through the hepatic circulation may restrict the pathological pro-
cesses to the liver.

Sequence in tJie Organs Wliich Are Affected by General Tuberculosis.
The author has already called attention (Berliner Archiv, Yol.
XIV) to the fact that in generalized tuberculosis of cattle a certain
sequence of participation of various organs is to be observed. One
finds uniformly an infection of the lungs and liver ; then follows the
spleen and kidneys, and then the prescapular and inguinal glands,
udder, bones and joints.

When the posterior part of the peritoneum in female animals is.
affected, the uterus is also attacked, almost without exception.



TUBERCULOSIS 623

It is a remarkable fact that in generalized tuberculosis of young
cattle (up to four years of age), the spleen is almost always affected
and the kidneys are free from tuberculous foci, while in older
cattle the kidneys, but not the spleen, uniformly show tuberculous
alterations.

In hogs, the lungs, liver, spleen and kidneys are similarly
affected in generalized tuberculosis. Furthermore, affections of the
bones in hogs, especially the vertebral column, are much more
frequent than in cattle. Eieck, in 430 cases of general tuberculosis
in cattle identified at the abattoir in Leipsic, 1880 to 1891, deter-
mined the following sequence in the affection of different organs :
Lungs, 100 per cent.; liver, 83 ; alimentary canal, 73; serous mem-
branes, 57.4; kidneys, 52.5; meat, 49.3; spleen, 18.6; udder, 16.7;
bones, 8.8.

Moreover, Eieck found that 80 per cent, of the cases of tuber-
culosis were restricted to the lungs or bronchial glands. Several
organs of one cavity of the body, usually the thoracic cavity, were
affected in but 3.9 per cent. ; the processes extended beyond the
thoracic cavity in 1888 in 9.3 per cent, of the cases ; in 1889, in 13.3;
in 1890, in 11.9; and in 1891, in 19.6 per cent, of the cases. In a
considerable proportion of the last-named cases, only the lungs
and mesenteric glands were affected. Tuberculosis of the serous
membranes was demonstrated in Leipsic in 10.8 per cent, of all
tuberculous cattle (7.2 of male and 14.8 of female animals).

7. EXAMINATION OP SLAUGHTERED TUBERCULOUS ANIMALS.

For determining the extent of the disease in animals found to
fae tuberculous, it is desirable to adopt a certain method of inspec-
tion.*

The essential features of this method of inspection consist in
first subjecting to a regular examination the organs and groups of
lymph glands which may be affected by general infection, and
which, according to present knowledge, are most important in the
determination of generalized tuberculosis. For this purpose the
most important organs are the lungs, liver, spleen, kidneys, sexual
organs, sternum and vertebral column ; also the prescapular, axil-
lary, popliteal, kneefold and inguinal glands.

Affections of the bones of the extremities, joints and skeletal
musculature are always characterized by alterations of the last-

* With reference to the determination of primary tuberculous alterations in.
slaughtered animals, compare page 617.



624 INFECTIOUS DISEASES

named lymphatic glands. Affections of the meninges of the brain,
the myocardium and the tongue possess only a slight significance,
since they are seldom present and then only in the most pronounced
cases of generalization. A quite subordinate role in the determina-
tion of generalized tuberculosis is played by the affections of the
serous membranes. In judging the meat of tuberculous cattle, one
must become accustomed to disregarding completely the affections
of the pleura and peritoneum.

It should always be remembered that, as shown by Schmidt-
Miilheim, peritoneal tuberculosis may pass over in a purely local
manner to the pleura. Peritoneal tuberculosis, moreover, may be
associated with a local process in the lungs, either with or with-
out affection of the pleura and without generalization in cases
where bronchial slime is swallowed and gives rise to an affection
of the intestine, or, what is more frequent, to the mesenteric glands
(auto-infection). Tuberculosis of the serous membranes, particu-
larly of the peritoneum, comes into consideration only in case of
affection of the uterus, since in this organ a local invasion of the
specific process from the peritoneum to the mucous membrane is
possible and frequent. The greatest extension of tuberculosis
upon the peritoneum and pleura may, however, occur with the
complete integrity of the parenchyma of the lungs, liver, spleen,
etc.,* while, on the other hand, in the typical picture of acute
miliary tuberculosis, or of chronic general tuberculosis with exten-
sive alterations, even of the lymph glands, which lie in the skeletal
musculature, the serous membranes are often only slightly or not
at all affected.

A significance equally subordinate with that of the peritoneum
and pleura and their lymph glands, with regard to the determina-
tion of the question whether generalized tuberculosis exists, is
possessed by frequent alterations of the pericardium and epi-
cardium, trachea and larynx, as well as the lymph glands of the
head and mesenteries. The first-named alterations are usually
associated with tuberculous processes in the lungs ; the latter,
however, may arise in consequence of swallowing tuberculous
bronchial secretions (auto-infection, see above), or by the direct
ingestion of the specific virus with the food. I emphasize this
point for the reason that some importance in judging meat has
been erroneously ascribed to the affection of the mesenteric glands.

* For this reason distinction should be made in affections of the organs of
^the thoracic and abdominal cavities between parenchymatous tuberculosis and
tuberculosis of the serous membranes.



TUBERCULOSIS 625

The organs which for the determination of generalized tuber-
culosis are without significance are to be examined next in order
and merely for the purpose of determining what parts are to be
condemned in case of the eventual release of the meat.

The examination of parts which are important for reaching a
sanitary judgment on meat should not, as was formerly the general
custom, proceed from organs known to be diseased, but from those
which are presumably healthy. However unimportant this point
may seem, it can not be impressed too strongly upon the meat
inspector. Through the contamination of a liver by means of a
knife which was previously used in sectioning a tuberculous focus
in another organ, as, for example, the lungs, more damage can be
done in case the liver is released after the determination of its
intact character than under other conditions by the release of the
meat of an animal suffering from general tuberculosis. For, by the
above mentioned manipulation, the liver may receive a large quan-
tity of tuberculous virus. It therefore frequently happens that the
liver is eaten in an incompletely cooked condition. The muscula-
ture, on the other hand, is quite rarely the seat of tuberculous
alterations and even its lymphatic glands are only in certain cases
affected with generalized tuberculosis.

The practice which was formerly observed in certain locali-
ties of condemning all internal organs in all animals affected with
tuberculosis, but which were released for sale, is a radical and, so
far as human health is concerned, a safe one, but can not be
approved from a scientific standpoint or from a consideration of
the material loss to the producers. "When it can be determined
with certainty that the organ is free from pathological alterations, it
should never under any circumstances be withheld from sale. If,
however, it is contaminated with tuberculous material, this material
must be removed, but the expert has thereby committed a technical
error.

This technical error may be avoided if the examination of
tuberculous animals begins, not with the organs which are known
to be tuberculous, but with those which are presumably healthy.
I purposely emphasize this point since the warning already
sounded from another source (Deutscher Veterinar Kalender and
Zschokke), not to contaminate healthy parts by tuberculous
material, does not, in and of itself, furnish any guide for the mani-
pulation and may, perhaps, bring it about that the above direc-
tions are followed by merely washing the contaminated knife
before making an incision into an apparently healthy organ. More-



626 INFECTIOUS DISEASES

over, for reasons already given, all unnecessary cutting of tubercu-
lous foci should be avoided. Butchers should likewise be expressly
forbidden to cut into the tuberculous organs of tuberculous ani-
mals or to continue the operation of cutting up the animal with
knives used for this purpose.

The examination of slaughtered tuberculous animals must pro-
ceed postero-anteriorly, and, on animals which are hung up, from
above downward. We examine first of all the "meat" and the
lymphatic glands which receive the lymph from it, and then the
internal organs. In making the examination, the following sequence
may be observed :

1. Popliteal, kneef old, inguinal, pubic or supramammary lymph
glands.

2. In case of an intact peritoneum, the iliac and the other retro-
peritoneal lymph glands.

3. Vertebral column, ribs and sternum.

4 Pre scapular and axillary glands. (For the examination of
the latter, the anterior extremities must be removed. The prescap-
ular glands, however, may be conveniently reached without
removing the extremities by a simple incision in front of the
shoulder joint.)

5. The udder in female animals.

6. The kidneys and renal lymphatic glands. (The latter are
usually found by making an incision directly over the point wher*
the renal artery branches off from the aorta.)

7. Spleen.

8. Liver.

9. Lungs.

10. The other internal organs, together with the corresponding
lymph glands.

The characteristic symptoms of tuberculous affection of the
above named parts of the body have already been described in the
chapter on "Organic Diseases." In addition to the discussion
found there, the following notes may be added with reference to
the technique of the demonstration of tuberculous processes in
individual organs.

The tuberculous affection of the udder is best demonstrated by
palpation. The healthy udder, although of strikingly large size,
possesses in all its parts a uniformly, moderately soft character.
A tuberculous udder, on the other hand, as is well known, in case
of striking enlargement of one or more quarters, shows a firm, often



TUBERCULOSIS 627

-stony consistency of the affected parts. One must remove all
uncertainty concerning the nature of doubtful tubercular thicken-
ings present in the udder by means of a cross section. It should
be noted that Bang, in his well known work on tuberculosis of the
udder, called attention to the absence of softened spots (abscesses)
in tuberculosis of the udder. In general, abscesses in the udder
jire to be considered as non-tuberculous alterations. Any possible
doubt, however, may be easily removed by an examination of the
supramammary lymph gla>nds.

The kidneys and suprarenal bodies are to be removed from the
fatty capsule in situ, and after a superficial examination are to be
cut open by several sections running toward the renal pelvis.
Since, however, palpation as well as sectioning of the kidneys can
not be performed in such a satisfactory manner that a reliable con-
clusion can be drawn upon this basis, for the absence of tuberculous
foci, the aid of an examination of the lymph glands is indispensable
for reaching a diagnosis of the condition of the kidneys.

The tissue of the spleen should be examined by making
numerous parallel longitudinal sections. Moreover, even small
tubercles in the spleen may be demonstrated by palpation.

In case of the liver it must be insisted upon that the portal
lymph glands shall in no case be removed before a veterinary
inspection is made, for frequently these glands exhibit a much more
strikingly diseased condition than the tissue of the liver.

Similar conditions are present in case of the bronchial glands
and the lungs. Tuberculous alterations in the latter may be of two
sorts : There are either small or large cavities (primary pulmonary
tuberculosis) or round small and large tubercles (embolic pulmonary
tuberculosis). The cavities have their seat especially at the base
and apex, as well as in the lower border of the lungs. The embolic
foci, on the other hand, are uniformly distributed in the interlobu-
lar tissue.

When inspection is made according to the foregoing directions,
the inspector can, as a rule, decide without difficulty whether in
a particular case tuberculosis is local or generalized. The internal
organs, particularly the lungs, liver, spleen and kidneys, as well as
the intermuscular lymph glands, present a more favorable nutrient
medium for tubercle bacilli than the meat. The most recent alter-
ations, incipient tubercles, are therefore much more easily and
-certainly demonstrated in the internal organs and lymph glands
than in the various joints and in the marrow of the bones, quite
aside from the fact that the dissection of the meat for the purpose



628



INFECTIOUS DISEASES



of inspection is quite limited. The alterations in the organs, there-
fore, together with those which may be demonstrated in the skeleton r
musculature and intermuscular lymph glands, must be considered
as final criteria for deciding the question whether the case is one of



FIG. 219 a.



FIG. 219 b.





>9



Half of beef, seen from the outside. Half of beef, seen from the inside, a, super-
a, popliteal glands; b, kneefold ficial inguinal glands ; b, deep inguinal
glands; c, prescapular glands. glands (of variable size and not always pre-

sent); c, internal iliac glands; d, lumbar
glands ; e, renal glands ; /, lymphatic glands
of the inferior thoracic wall ; g, glands of
the superior thoracic wall ; h, lower cervical
glands.

local or generalized tuberculosis. By means of the above described
examination the organic alterations may be most perfectly deter-
mined, and, when taken together, give positive evidence on the
question whether tubercle bacilli have gained entrance into the=



TUBERCULOSIS



629



general circulation or have distributed themselves beyond the point
of entrance into the neighboring organs, or not. At the same



FIG. 219 c.




'Position of the most important lymphatic glands after removal of the retroperitoneal
fat tissue, a, lymphatic glands above th* hock; b, popliteal glands; c, super-
ficial inguinal glands; d, kneefold glands; e and /, internal iliac glands; g,
lymphatic glands of the lower thoracic walls; h, lower cervical glands ; i, upper
cervical glands; k, submaxillary glands.

it may be determined by the above described method of examination
what parts are to be destroyed in case the meat is released.

S. SANITARY JUDGMENT ON TUBERCULOSIS.
(a) Tuberculous Organs.

It must be assumed that tuberculosis may be transmitted to
man by the consumption of tuberculous organs. For, tuberculosis
of man and animals is produced by a bacillus which, in regard to its



630 INFECTIOUS DISEASES

iorm, stainability, growth, and transmissibility to small experi-
mental animals, exhibits no essential differences. Furthermore, it is
possible in a proportion of the cases, if not always, to transmit
human tuberculosis to cattle, hogs and sheep. Finally, a number
of cases is known in which tuberculosis of domesticated animals
has been transmitted to man (skin infection from handling tubercu-
lous material and alimentary tuberculosis after eating the milk of
cows affected with tuberculosis of the udder).

By means of experiments on animals it has been shown that
the tubercle bacilli introduced in food may be taken up by the
lymphatic apparatus of the gums and pharyngeal cavity, and that
they are also capable of passing through the stomach and may pro-
duce specific alterations in the intestines or mesenteric glands. A
necessary condition, however, is that the tubercle bacilli shall be
introduced in a certain quantity (see page 611).

Recently the question of the transmissibility of tuberculosis of
domesticated animals to man has been thrown into doubt by Robert
Koch on the basis of experiments which he carried out in coopera-
tion with Schiitz. In these experiments it was found impossible,
by any method of inoculating human tuberculosis, to render cattle,
nineteen in number, tuberculous, while, on the contrary, cattle
which were inoculated with tuberculous material from other cattle
became seriously affected and part of them died.

Before the experiments of Koch and Schiitz, Piitz, Theobald
Smith, Frothingham, Dinwiddie and Gaiser had demonstrated the
difficulty of transmitting human tuberculosis to cattle ; Koch and
Schiitz, however, conducted their experiments, in so far as they
operated with pure cultures, exclusively with one culture. This is
of the greatest significance in judging the results, as was shown by
the experiments of Thomassen. He infected four cattle with four
cultures of tubercle bacilli of various human origins and produced
positive results in two cases. Furthermore, Karlinski succeeded
in infecting cattle with human tuberculosis in ten cases during
twenty-five experiments. Similarly, Bollinger, Kitt, Frothingham,
Crookshank, Svennson, Delepin^, Arloing, Krebbs and Rievel, as
well as de Jong, obtained positive results in the transmission of
human tuberculosis to calves. We may, therefore, agree with
Thomassen when he states that it is difficult but not impossible to
transmit human tuberculosis to cattle.

In the case of hogs and sheep, even Koch and Schiitz suc-
ceeded in part of their experiments in producing tuberculosis, if
only of a local character, in the experimental animals by means uf



TUBERCULOSIS 631

tuberculous material of human origin. In hogs and sheep also r
tuberculous material of bovine origin was found to be much more
infectious than that of human origin.

The rarity of primary intestinal tuberculosis in man seems to
speak for the soundness of Koch's assumption. The question
should not be decided by this evidence, but rather by the occur-
rence of primary tuberculous alterations in the laryngeal, cervical
and mesenteric glands, which affections appear much more fre-
quently after the ingestion of tubercle bacilli with the food than
does a tuberculous affection of the intestinal mucous membrane.
Heller in Kiel recently found that in nearly one-half of the cases of
tuberculosis of children there was an affection of the mesenteric
glands. Moreover, Dr. Still, working on material obtained from
autopsies in a London hospital for children, found 29.1 per cent,
and Dr. Shennan in Edinburgh found primary tuberculosis in 28.5
per cent, of the cases of tuberculosis in children.

Negative results in the transmission of a given race of tuber-
culous cultures of bovine origin to man, as reported by Baum-
garten, are not sufficient, according to the results of the experi-
ments by Thomassen and Karlinski, to prove the non-transmissi-
bility to man of bovine tuberculosis.

In favor of the possibility of the transmissibility of bovine
tuberculosis to man we have the case of Moses, that of Priester,
several cases of skin tuberculosis of animal origin and cases of
alimentary tuberculosis which have been observed in man after
drinking tuberculous milk. The veterinarian, Moses, of a healthy
family, received in the summer of 1885, a wound on the left thumb
while making a post-mortem examination of a tuberculous cow.
The wound healed without suppuration, although the point of the
knife probably penetrated into the joint. After six months, how-
ever, a so-called skin tubercle developed on the cicatrix and the
joint became loose. In the autumn of 1886 acute catarrh appeared,
and thereupon a chronic hoarseness, and, in January, 1887, death
resulted (Pfeiffer). Priester reported a case, observed in a surgi-
cal clinic in Kiel, of skin tuberculosis in a man who for the pur-
pose of removing a tattooing of the skin pricked the tattoo marks
and rubbed milk into the punctures. This operation was repeated
several times. Skin tuberculosis developed in the punctures which
were rubbed with milk on a certain day.

Concerning skin tuberculosis in veterinarians and butchers,
which may be ascribed to infection with bovine tuberculosis, we



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