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United States. Bureau of Animal Industry.

Special report on diseases of cattle and on cattle feeding online

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may also develop in the spleen, the kidneys, the uterus and ovaries, and
the testicles.

Tubercular a flection of the intestines seems to be quite rare, although
ulc.-rs ut' the large intestines have been observed. Nodules may also
form under the serous covering of the intestines.

The brain and spinal cord are occasionally found tuberculous. Of
40 cases, Scinmer found tuberculosis of the brain in 4. It is not
improbable that, owing to the infrequency of exposing the brain and
spinal cord, tuberculosis may have escaped the attention of patholo-
gist*, and it may be that it is not so uncommon as is generally supposed.
The tubercles occur on the membranes of the brain as well as in the
subst ance of the brain itself. They project into the ventricles as masses
varying in sixe from a pin's head to a hen's egg. They finally lead to
various inflammatory changes. Johne has observed numerous small
tubercles on the membranes of the spinal cord.

Y<TV rarely tuberculous lesions have been observed in the bones and

muselrs of the body. Not so rare, however, is the aftectioii of the

lymphatic glands imbedded in the muscular tissue and those which can

be idt l>eneath the skin. These are situated at the joints, under the

and along the neck.

Tubercular disease of the udder in cows has received considerable
attention of late from sanitarians, owing to the infection of the milk
wit h the virus of tuberculosis. According to those who have given this
eet special attention the udder becomes swollen uniformly and
quite linn. This swelling, which is painless, frequently attacks but one
qnarN'r. more rarely two. these being usually the hind quarters. The
larger milk ducts contain yellowish cheesy particles, in which are many



404 DISEASES OF CATTLE.

tubercle bacilli. Later on, larger nodules can be felt within the udder,
which undergo the various changes to which tubercles are subject. The
udder may grow very hard to the touch and become very large, weigh-
ing in some cases up to 40 pounds. The milk, at first normal, becomes
thin and watery after a month or so, and is mixed with flakes and tuber-
cle bacilli.

As regards the frequency of the tubercular processes in the different
organs, the following carefully compiled statistics of the disease in
Bavaria and Baden may serve as a guide:

Bavaria : Ter cent.

Tuberculosis of lungs and serous membranes 41

Tuberculosis of lungs alone 33

Tuberculosis of serous membranes alone (pearly disease) 17

Tuberculosis of other organs 8

Baden :

Tuberculosis of lungs alone 21

Tuberculosis of serous membranes alone .- 28

Both combined 39

Generalized tuberculosis 9

Tuberculosis of the sexual organs alone 3

Symptoms. The beginning of the disease usually passes unnoticed,
inasmuch as it is very slow and insidious and rarely accompanied by
fever. When the lungs are involved a dull, short cough is noticed,
which may later on become prolonged, convulsive, and very trouble-
some to the animal. The cough is more frequent in the morning after
movement and drinking. The breathing varies. Only when much of
the lung tissue is diseased, it is labored and accompanied by active
movements of the chest and nostrils. Discharge from the nose is rare
or absent. At times, however, when the tubercles have broken down
and cavities containing cheesy masses have formed in the lung tissue,
or when the air- tubes have become filled with cheesy and mucous masses,
coughing will dislodge these and cause their discharge. In advanced
stages the breath may have a disagreeable odor. Pressure on the chest
wall may give rise to pain.

The general effect on the body is at first slight. In fact, animals may
remain in good flesh for a considerable time. Invariably, as the dis-
ease progresses, loss of flesh and appetite and paleness of the mucous
membranes become manifest. These are accompanied by a gradual
diminution of the milk secretion. The debilitated condition of the
animal is also manifested by a staring coat and a tough, dry, harsh
skin (hide-bound). Digestive disturbances are indicated by tympa-
nitis, or distension of the rumen by gas, colic, and diarrhea, alternating
with constipation. The animal generally dies from exhaustion after a
period of sickness which may last months and years.

Tuberculosis in the abdominal organs is often signalized by abortion
and by abnormal sexual manifestations. When the brain is involved
the disease may cause convulsions, unconsciousness, paralysis, as well
as peculiar movements in a circle, oblique position of the head, etc.



KCTIOUS DISEASES OF CATTLE. 405

Lydtin quotes the following description of the disease as taken from a

.Swiss sanitary order:

A dry, short, interrupted, hoarse cough, -which the sick animals manifest espe-
cially in the morning at feeding time, still more after somewhat violent exertion. At
tir>r these animals may be full-blooded and lay on a considerable amount of fat
when well fed. As the disease progresses they grow thin and show more and more
those appearances which indicate diseased nutrition, such as a staring, lusterlesa,
disheveled coat; dirty, tense skin, which appears very pale in those regions free
from hair. The temperature of the skin is below normal. The loss of fat causes
sinking of the eyes in their sockets. They appear swimming in water, and their
expression is weak. The- cough is more frequent, but never or very rarely accom-
panied with discharge. The body continues to emaciate even with plenty of food
and a good appetite, so that the quantity of milk is small. At times, ir the early
stages of the disease, still more in the later stages, the diseased animals manifest
considerable tenderness when pressure is applied to the front or the sides of the
chest, by coughing, moaning, etc. Often all symptoms are wanting in spite of the
existence of the disease.

Lydtin also quotes at length a description of the abnormal sexual
desire occasionally observed among cows when affected with this dis-
ease. ^ '

Diagnosis. A disease so varied in its attack upon the different
organs of the body and in the extent of the disease process must neces-
sarily lead to mistakes of diagnosis. It has been confounded with the
later stages of pleuro-pneumonia, with parasitic diseases of the brain,
the lungs, the intestines, and with actinomycosis. In the early stages
of the disease diagnosis is very difficult. The various procedures
which have been suggested from time to time are all based on the
detection of the tubercle bacilli, .and therefore can only be made use of
by trained veterinarians. At present a method is under trial which
may bo destined to solve the difficulty. It consists in injecting beneath
the skin a certain quantity of a liquid which represents an extract of
tubercle bacilli. In cattle which are tuberculous, even to a slight
degree, an elevation of temperature or a temporary fever will follow
'the injection. In those which are healthy no such reaction takes place.
Whether the method will prove to be all that it promises can not be
definitely stated at this time. If it should it will be a great assistance
to the veterinarian in the detection of this disease.

Treatment of the disease is not seriously considered by any authori-
ties at the present time.

The measures to be adopted to prevent the spreading of the disease
must take into consideration not only the tubercle bacillus, but like-
wise all those circumstances which make cattle more susceptible to the
<ii-ease, which have already been dwelt upon. It would be useless
to repeat here all that has been said above on the transmission of tuber-
elr bacilli from one animal to another, and on the dangers of certain
debilitating influences. A careful study of these will show how tuber-
-ulosis may, at least in some cases, be prevented. The difficulty of
determining when cattle first become tuberculous makes it imi>os8ible
to prevent the legibility of infection. Great care should therefore be



DISEASES OF CATTLE.

bestowed upon the breeding, the surroundings, and the food of the ani-
mal, so that the latter may be put into a condition to resist infection
even when exposed to it. If the method of diagnosis referred to above
proves a success, this should be used whenever strange cattle are intro-
duced into a herd. A rigid exclusion of tuberculous animals, if this
were possible, would be all that is necessary to prevent the appearance
of the disease, provided cattle are not infected by consumptive per-
sons and animals, which we can not consider as impossible at the pres-
ent time.

Tuberculosis in cattle must also be considered as bearing upon tuber-
culosis of other domesticated animals, particularly swine. In Europe
this disease is not so uncommon among swine, while in our own coun-
try it seems to be practically unknown. The reason for its existence in
Europe may be looked for in the feeding of pigs with whey in dairies,
with the offal of the abattoirs and the household refuse generally. If
tuberculosis is common among cattle it is likely to be transmitted to
swine kept in this way. There is, however, still some confusion of tuber-
culosis with other swine diseases, and it may be that the statistics are
much too high.

The carcasses of animals which have died of tuberculosis should be
bulled deeply, so that they can not be eaten by other animals. This is
likewise true of all organs or tissues of slaughtered animals containing
tubercles. These should never be fed to other animals, such as swine,
dogs, and cats, and should either, be destroyed by fire or else deeply
buried.

Bovine tuberculosis and the public health. The identity between hu-
man and animal tuberculosis, combined with the extraordinary mor-
tality of human beings from this disease, often amounting to from 10 to 14
per cent, has raised the question in all civilized countries as to how far
animal, and especially bovine, tuberculosis was to blame for this high
mortality. The medical and veterinary professions have approached
this problem with equal zeal, and much has come to light within recent
years which enables us to come to some conclusion. If this disease is
transmitted from animals to man, how does the transmission take place ?
As comparatively few people come in direct contact with tuberculous
cattle, it must be, if at all, either through the meat or the milk, or
through both, that the virus enters the human body. The question
has thus narrowed itself down to the food products furnished by cattle.

It has become a very urgent question, especially in the poorer coun-
tries of Europe, whether all flesh from tuberculous animals is unfit for
human food. It is argued there that if it can be shown that in the
majority of cases of tuberculosis the bones and the muscular system are
free from infection, there is no reason why the meat should not be put
on sale under certain restrictions. The question may be resolved into
two divisions : (1) How frequently does the disease invade those parts
of the body which are used as food '? (2) "When the disease process is
manifestly restricted to the internal organs do tubercle bacilli circulate



INFECTIOUS DISEASES OF CATTLE. 407

in the blood and lymph, and can they be detected in the muscular

(1) Disease of the bones is not unknown, although very rare. Accord-
ing to Walley it appears chiefly in the spongy bones of the head and
backbone and in the long bones of the limbs. Occasionally the ends of
the bones, where they are covered by the synovial membrane of the
joints, are dotted with tubercles. The muscular system itself is very
rarely the seat of tubercular deposits, although the lymphatic glands
lying near and among the muscles may be not infrequently diseased.

(2) Whether tubercle bacilli are found in muscle juice independent
of any tubercular deposits is a question which must be approached
experimentally. There is on record a great variety of opinions on this
matter, some authorities considering all flesh from tuberculous animals
unfit for food, while others hold a contrary view. Experiments have
shown that in rare cases the flesh of tuberculous cattle contains a small
number of tubercle bacilli. In Germany the flesh of animals in which
the disease is just beginning, or in which it is restricted to one or more
related organs, is not rejected. When, however, the disease has
aft'ected the muscles, or bones, or lymphatic glands situated on or
between them, the flesh is condemned as unfit and dangerous. Animals
are also rejected in which it is evident, from the general distribution of
tubercles throughout the various organs, that the bacilli have beeu
distributed by the blood and may have been carried into the muscular
system (generalized tuberculosis).

Concerning the infections nature of milk secreted by tuberculous
. authorities have universally agreed that when the udder itself is
in the slightest degree involved the milk possesses infectious propcr-
and is therefore dangerous. Tubercle bacilli have been found in
large numbers, in the milk and the udder under such circtimsta:
I'nlike other affections of the udder, tuberculosis of this organ does not
at once change the appearance and the quality of the milk secreted.
Bang states that for at least a month after the disease has appeared the
milk is normal in appearance and may be consumed and sold without
arousing the suspicion of the owner. There is, therefore, considerable
danger involved in this disease, and the necessity for the careful \i\>
tion of dairy cows seems more urgent than ever before.

Authorities are, however, not fully agreed as to whether the milk
from tuberculous cows in which the udder is apparently not invaded
liy the disease should be considered dangerous or not. Some are in-
clined to believe that the milk secreted by healthy udders is never
infeetious even when the lungs or other organs are affected; that,
in oilier words, the tubercle bacilli are rarely, if ever, separated from
the lesions which they produce, and that the udder itself must be dis-
eased before tubercle bacilli can apj>ear in the milk. Experiment*
made tvith the milk of tuberculous cows in which there were no indica-
of udder disease do not bear out this theory, since tubercle bacilli
have been found in the milk of such cows. Some authorities, among



408 DISEASES OF CATTLE.

them Nocard, still believe that the udder is diseased when the milk is
infected, but that the disease escapes observation. However this may
be, the fact that the udder may be diseased and the disease not recog-
nizable, simply casts suspicion upon all milk from tuberculous animals.
The question as it now stands leaves the matter unsettled. We know
that the milk of tuberculous cattle may or may not contain tubercle
bacilli when the udder is apparently free from disease. But we have
no rapid method of determining whether in any given case the milk
contains tubercle bacilli or not. Moreover, the bacilli may be absent
at one time and present at another in inilk from the same cow. When
we consider, therefore, the extent of tuberculosis and the hidden char-
acter of the disease, a certain amount of suspicion rests upon all milk.
Fortunately tubercle bacilli are readily destroyed by the temperature
of boiling water, and hence both meat and milk are made entirely safe,
the former by the various processes of cooking, the latter by boiling
for a few moments. Until better means of diagnosis are at hand it is
incumbent upon all communities to have dairy cows examined or
inspected "at least to the extent of finding out whether the udder shows
any signs of disease. If this is detected the affected animal should be
at once killed, or else all opportunity for the sale of such milk removed
by appropriate measures. The dangers from infected milk might by
these means be very materially lessened.

TUBERCULOSIS.

[Description of plates.]

PLATE XXXIV. Tuberculosis of the lungs. The upper figures represent a large
cheesy mass, surrounded lay a capsule of connective tissue, the whole embedded in
healthy lung tissue. The lower figure illustrates in section a mass of tubercles
which have undergone cheesy degeneration, and some of which are embedded in dense
connective tissue.

PLATE XXXV. Tuberculosis of the liver. A large portion of the lobe represented
in the plate has undergone tuberculous changes. The whitish, very fine, newly
formed connective tissue contains the yellowish, partly cheesy, partly gritty masses
characteristic of advanced tuberculous degeneration. This large mass projected
above the surface of the liver. In the plate the diseased mass is shown cut through
its central portion with the cut surface presented.

PLATE XXXVI. A lymph gland from the region of the thorax behind or above
the oesophagus or gullet (posterior or dorsal mediastinum). The gland is shown cut
through and laid open. It is very much enlarged, and the yellowish cheesy masses
surrounded by dense connective tissue are well shown on the cut surface.

PLATE XXXVII. Represents the omentum or caul of a tuberculous cow. The
preparation had been in alcohol for some time. The projecting masses are the
tubercles, whence the name "pearly disease," for that form of the malady in which
these tubercles are present. They are mainly restricted to the lining membrane of
the thorax and abdomen.

PLATE XXXVIII. Fig. 1. Lymphatic gland of the mesentery (the fold of mem-
brane to which the small intestines are attached) cut open. The gland is very
much enlarged. The yellowish portions represent tissue which has undergone
tuberculous changes.

Fig. 2. Omentum or caul resting upon the paunch. The reddish nodules with
which the membrane is beset are tubercles, the product of the disease. Both speci-
mens are from the same animal, a Jersey cow.



PI.ATK XXXIV






I M I I ( ) S I S ( >| ' I I I I I I ' \ ( , s




i







-







PLATE XXXMl




TriiKm ri.osis 01 TIIK O.MKMTM (< AIIJ.



PLATK XXXVIII



Fig.l




Fig. 2




Kami's ilri



TriiKHCl'LOSIS OK LYMPHATIC (il.AXI)
AN'I) OK OMKNTI'.M (('AIM.. I



INFECTIOUS DISEASES OF CATTLE. 409

ACTINOMYCOSIS.
(Plates xxxix to XLI, inclusive.)

Actinomycosis, also known as lump-jaw, big-jaw, etc., is a local dis-
ease due to the formation of peculiar tumors in various regions of the
body, more particularly the head. In these tumors a certain fungus
(actinoinyces) is always present and regarded as the cause of the disease
process.

Although these tumors on cattle had been the object of study for
many years, it was not until 1877 that the constant presence of actino-
myces was pointed out by Bollinger, of Munich, and since that time
considered the cause. This fungus had been observed in these tumors
as early as 18G3 by Rivolta, and by others subsequently, without having
been suspected as causing them.

-Since Bolliuger's publication a large amount of work has been done,
many observations made, and many hitherto obscure disease proc-
* brought into relation with this fungus. Furthermore, a similar
disease in man was first definitely shown to be associated with the same
fungus in 1878 by Israel, and in the following year Ponfick pointed out
that the disease described by Bollinger in animals and that found by Israel
in man were due to the same cause; that is, that the fungi described by
these observers were one and the same.

The tumors and abscesses wherever they may be situated are all found
to l>e the same in origin by the presence of the actinomyces fungus.
When they are incised, a very close scrutiny with the naked eye, or at
most a hand lens, will reveal the presence of minute grains which vary
from a pale yellow to a sulphur-yellow color. They may be very abun-
dant or so lew as to be overlooked. They are embedded in the soft
tissue composing the tumor or in the pus of the abscess. With a needle
they are easily lifted out from the tissue and then they appear as roundish
masses about one-half millimeter (^ inch) in diameter. To anyone
familiar with the use of a microscope the recognition of these grains or
particles without any previous preparation is a comparatively easy task.

When examined in the fresh condition under a microscope magnify-
ing up to 250 diameters the general structure is made out without
much difficulty. These grains consist of collections of minute roundish
masses. Their outer surface is made up of club-shaped bodies all radi-
ating from the center of the mass (see Fig. 2 of Plate xxxix). somewhat
like a rosette. If the fungus be crushed the interior is found made up
of bundles of very fine filaments, which are probably continuous into
the club-shai>ed bodies. The addition of a dilute solution of caustic
soda or potash greatly aids the examination, since it removes the layer
of cells adhering to the fungus which obscures the structure. Now
and then these grains are found to be in a calcified condition. The
< \t-rior is incnisted in lime salts, which are dissolved by adding .some
\vcak dilute acid like acetic acid. Only by this procedure can the fun-
gus be definitely recognized when in a mummified condition.



410 DISEASES OF CATTLE.

These are the bodies whose presence causes sufficient irritation in
the tissues into which they find their way to set up inflammatory
growths. These growths increase as the fungus continues to multiply
until they reach enormous dimensions, if the affected animal is per-
mitted to live long enough. The true nature of this parasite is not yet
definitely settled, although many excellent observers have occupied
themselves with it. According to earlier observers it is a true fungus.
Later ones are inclined to place it among the higher bacteria. Further
investigations will be necessary to clear up this subject. Whatever
be the situation of the disease caused by actinomyces, its nature is
fundamentally the same and peculiar to the fungus. The pathological
details which make this statement clear can not be entered upon in
this place, nor would they be of any practical value to the farmer.
We will simply dwell upon a few obvious characters.

The consistency of the tumor varies in different situations according
to the quantity of fibrous or connective tissue present. When very
little of this is present the tumor is of a very soft consistency. As the
quantity of connective tissue is increased the tumor is firmer and of a
more honeycombed appearance. The individual actiuoinyces colonies
are lodged in the spaces or interstices formed by the mesh work of the
connective tissue. There they are surrounded by a mantle of cellular
elements which fill up the spaces. By scraping the cut surface of such
a tumor these cell masses inclosing the fungi come away, and the latter
may be seen as pale or sulphur-yellow specks, as described above.

Location of the disease. In cattle the disease process may be located
both externally, where it is readily detected, and in internal organs. Its
preferred seat is on the bones of the lower and upper jaw, in the pa-
rotid salivary gland in the angle of the jaw, and in the region of the
throat. It may also appear under the skin in different parts of the
body. Internally it may attack the tongue and appear in the form of a
tumor in the mouth, pharynx, and larynx. It may cause extensive
disease of the lungs, more rarely of the digestive tract.

It appears, furthermore, that in certain districts or countries the dis-
ease seems to attack by preference certain parts. Thus in England
actinoinycosis of the tongue is most prevalent. In Denmark the soft
parts of the head are most prone to disease. In certain parts of Ger-
many actinomycotic tumors of the throat (pharynx), in others disease
of the jawbones is most frequently encountered.

A description of actinoinycosis of the jaw (lump-jaw) and of the
tongue has already been given by Dr. Murray, and hence they will
be dealt with here only very briefly. When the disease attacks the
soft parts of the head a rather firm swelling appears in which are
formed one or more smaller projecting tumors varying from the size
of a nut to that of an egg. These push their way outward and finally
break through the skin as small, reddish, fungus-like bodies covered
with thin sloughs. Or the original swelling, in place of enlarging in



INFECTIOUS DISEASES OF CATTLE. 411

the manner described, may become transformed into an abscess which
finally bursts to discharge creamy pus. The abscess cavity, however,
does not disappear, but is soon filled with fungus-like growths which
force their way outward through the opening.

When the tumors are situated within the cavity of the pharynx, they
have broken through from some gland, perhaps beneath the mucous



Online LibraryUnited States. Bureau of Animal IndustrySpecial report on diseases of cattle and on cattle feeding → online text (page 47 of 56)