concerning this cattle disease is largely due to the fact that the same
disease attacks human beings. Its slow progress, its tendency to remain
restricted to certain localities, and the absence of any directly
contagious properties have thus far not aroused any anxiety in other
countries as to its influence on the cattle industry, not even to the point
of placing it among the infectious diseases of which statistics are
annually published. Its possible bearing on public health has, however,
given the disease a place in the public mind which it hardly deserves.
It has already been stated that the actinomyces fungus found in human
disease is considered by authorities the same as that occurring in bovine
affections. It is therefore of interest to conclude this article with a
brief discussion of the disease in man and its relation to actinomycosis in
cattle.
In man the location of the disease process corresponds fairly well to that
in cattle. The majority of cases which have been reported in different
parts of the world--and they are now rather numerous--indicate disease of
the face. The skin, tongue, or the jawbones may become affected, and by a
very slow process it may extend downward upon the neck and even into the
cavity of the chest. In many cases the teeth have been found in a state of
more or less advanced decay and ulceration. In a few cases disease of the
lungs was observed without coexisting disease of the bones or soft parts of
the head. In such cases the fungus must have been inhaled. The disease of
the lungs after a time extends upon the chest wall, where it may corrode
the ribs and work its way through the muscles and the skin. An abscess is
thus formed discharging pus containing actinomyces grains. Disease of the
digestive organs caused by this fungus has also been observed in a few
instances.
Granting the identity of the disease in man and cattle, the question has
been raised whether cattle are responsible for its occurrence in man. Any
transmission of the infectious agent may be conceived of as taking place
during the life of the animal and from the meat after slaughter. That human
beings have contracted actinomycosis by coming in contact with diseased
cattle is not shown by the cases that have been reported, for the
occupations of most of the patients did not bring them into any relation
whatever with cattle. While the possibility of such direct transmission is
not denied, nevertheless it must be considered as extremely remote.
Practically the same position is maintained at present by most authorities
as regards the transmission of the disease to man by eating meat. Israel,
who has studied this question carefully, found the disease in Jews who
never ate pork,[5] and who likewise were protected from bovine
actinomycosis by the rigorous meat inspection practiced by that race.
Furthermore, it must be borne in mind that actinomycosis is a local
disease, causing great destruction of tissue where the fungus multiplies,
but which very rarely becomes generally disseminated over the body from the
original disease focus. The fungus is found only in places where the
disease process is manifest to the eye or becomes so in a very short time
after the lodgment of the fungus. Only the greatest negligence would allow
the actually diseased parts to be sold and consumed. Finally, this
parasite, like all others, would be destroyed in the process of cooking.
Most authorities thus do not believe that actinomycosis in man is directly
traceable to the disease in animals, but are of the opinion that both man
and animals are infected from a third source, which has already been
discussed above. How far these views may be modified by further and more
telling investigations of the parasite fungus itself no one can predict.
There are still wide gaps in our knowledge, and the presentation above
simply summarizes the prevailing views, from which there are dissenters, of
course. An attempt to give the views of both sides on this question would
necessitate the summarizing and impartial discussion of all the experiments
thus far made--a task entirely beyond the scope of the present work.
Whether an animal affected with actinomycosis should be used for human food
after all diseased organs and tissues have been thoroughly removed is a
question the answer to which depends on a variety of circumstances. Among
these may be mentioned the thoroughness of the meat inspection itself, the
extent of the disease, and the general condition of the animal affected.
The Federal meat-inspection regulations require that carcasses of animals
showing generalized actinomycosis shall be condemned. If carcasses are in a
well-nourished condition, showing uncomplicated localized lesions of
actinomycosis, they may be passed after the infected organs or parts have
been removed and condemned. When the disease of the jaw is slight, strictly
localized, and without pus formation, fistulous tracts, or lymph-gland
involvement, the tongue, if free from disease, may be passed. The heads
affected with actinomycosis (lumpy jaw), including the tongue, shall be
condemned, except that when the lesions in the jaw are strictly localized
and slight in extent, the tongue may be passed, if free from disease.
ANTHRAX.
Anthrax or charbon may be defined as an infectious disease which is caused
by specific bacteria, known as anthrax bacilli, and which is more or less
restricted by conditions of soil and moisture to definite geographical
localities. While it is chiefly limited to cattle and sheep, it may be
transmitted to goats, horses, cats, and certain kinds of game. Smaller
animals, such as mice, rabbits, and guinea pigs, speedily succumb to
inoculation. Dogs and hogs are slightly susceptible, while fowls are
practically immune. The variety of domesticated animals which it may attack
renders it one of the most dreaded scourges of animal life. It may even
attack man. Of this more will be stated further on.
* * * * *
ACTINOMYCOSIS (LUMPY JAW).
DESCRIPTION OF PLATES.
PLATE XXXIX. Actinomycosis. (From Jˆhne's Encyklop‰die d. gesammt.
Thierheilkunde.)
Fig. 1. Actinomycosis of the jaw. The lower jawbone has been extensively
eaten away by the disease.
Fig. 2. Actinomyces fungus from a tumor of the jawbone in cattle, magnified
550 times.
PLATE XL. Actinomycosis of the jaw. (Reduced one-half. From Jˆhne's
Encyklop‰die d. gesammt. Thierheilkunde.) The lower jaw is sawed through
transversely, i.e., from right to left, and shows the disease within the
jawbone itself; _a_, within the mouth, showing the papillÊ on the mucous
membrane of the cheek; _b_, front view of a molar tooth; _c_, the skin
covering the lower surface of the jawbone; _d_, the jawbone hollowed out
and enlarged by the formation of cavities within it, which are filled with
the soft growth of the actinomycotic tumor. The section makes it appear as
if the bone were broken into fragments and these forced apart; _e_, a
portion of the tumor which has broken through the bone and the skin and
appears as a tumor on the cheek. The little roundish masses represent the
granulomata (minute tumors) in which the fungus vegetates.
PLATE XLI. Actinomycosis of the lungs.
Fig. 1. Transverse section of the ventral lobe of the right lung, from a
case studied in the laboratory. The yellowish dots represent the places
where the actinomyces fungus is lodged. The larger yellowish patches are
produced by the confluence of a number of isolated centers. The entire lobe
is of a dark flesh-red color, due to collapse and bronchopneumonia.
Fig. 2. The cut surface of a portion of the principal lobe of the same
lung, showing the recent invasion of antinomycosis from the other lobe:
_a_, large air tube; _b_, artery; _c_, a pneumatic lobule; _d_, lobule
containing minute yellowish dots. In these the actinomyces fungus is
lodged.
Fig. 3. Cut surface of a small portion of another lung, showing a few
lobules, _a._ The fungus is sprinkled throughout the lung tissue in the
form of yellowish grains, as shown in the illustration. The pleural
covering of the lung tissue is shown in profile above.
[Illustration: PLATE XXXIX.
Fig. 1
Fig. 2
ACTINOMYCOSIS.]
[Illustration: PLATE XL. ACTINOMYCOSIS OF THE JAW.]
[Illustration: PLATE XLI.
Fig. 1
Fig. 2
Fig. 3
ACTINOMYCOSIS OF THE LUNGS.]
* * * * *
_Cause._--The cause of anthrax is a microscopic organism known as the
anthrax bacillus. (See Pl. XXVIII, fig. 7.) In form it is cylindrical or
rodlike, measuring 1/5000 to 1/2500 inch in length and 1/25000 inch in
diameter. Like all bacteria, these rodlike bodies have the power of
indefinite multiplication, and in the bodies of infected animals they
produce death by rapidly increasing in numbers and producing substances
which poison the body. In the blood they multiply in number by becoming
elongated and then dividing into two, each new organism continuing the same
process indefinitely. Outside the body, however, they multiply in a
different way when under conditions unfavorable to growth. Oval bodies,
which are called spores, appear within the rods, and remain alive and
capable of germination after years of drying. They also resist heat to a
remarkable degree, so that boiling water is necessary to destroy them. The
bacilli themselves, on the other hand, show only very little resistance to
heat and drying. It has long been known that the anthrax virus thrives best
under certain conditions of the soil and on territories subject to floods
and inundations. The particular kinds of soil upon which the disease is
observed are black, loose, warm, humous soils; also those containing lime,
marl, and clay, finally peaty, swampy soils resting upon strata which hold
the water, or, in other words, are impervious. Hence fields containing
stagnant pools may be the source of infection. The infection may be limited
to certain farms, or even to restricted areas on such farms. Even in the
Alps, more than 3,000 feet above sea level, where such conditions prevail
in secluded valleys, anthrax persists among herds.
Aside from these limitations to specific conditions of the soil, anthrax is
a disease of world-wide distribution. It exists in most countries of
Europe, in Asia, Africa, Australia, and in our own country in the lower
Mississippi Valley, the Gulf States, and in some of the Eastern and Western
States. It seems to be gradually spreading in this country and every year
occurs in new districts.
Meteorological conditions also have an important share in determining the
severity of the disease. On those tracts subject to inundations in spring a
very hot, dry summer is liable to cause a severe outbreak. The relation
which the bacillus bears to these conditions is not positively known. It
may be that during and immediately after inundations or in stagnant water
the bacilli find nourishment enough in the water here and there to multiply
and produce an abundant crop of spores, which are subsequently carried, in
a dry condition, by the winds during the period of drought and disseminated
over the vegetation. Animals feeding upon this vegetation may contract the
disease if the spores germinate in the body.
Another source of the virus, and one regarded by many authorities as
perhaps the most important, is the body of an animal which has died of
anthrax. It will be remembered that in such bodies the anthrax bacilli are
present in great numbers, and wherever blood or other body fluids are
exposed to the air on the surface of the carcass there the formation of
spores will go on with great rapidity in the warm season of the year. It
will thus be readily understood how this disease may become stationary in a
given locality and appear year after year and even grow in severity if the
carcasses of animals which have succumbed to it are not properly disposed
of. These carcasses should be buried deeply, so that spore formation may be
prevented and no animal have access to them. By exercising this precaution
the disease will not be disseminated by flies and other insect pests.
We have thus two agents at work in maintaining the disease in any
locality--the soil and meteorological conditions, and the carcasses of
animals that have died of the disease. Besides these dangers, which are of
immediate consequence to cattle on pastures, the virus may be carried from
place to place in hides, hair, wool, hoofs, and horns, and it may be stored
in the hay or other fodder from the infected fields and cause an outbreak
among stabled animals feeding upon it in winter. In this manner the
affection has been introduced into far-distant localities.
_How cattle are infected._--We have seen above that the spores of the
anthrax bacilli, which in their functions correspond to the seeds of higher
plants and which are the elements that longest resist the unfavorable
conditions in the soil, air, and water, are the chief agents of infection.
They may be taken into the body with the feed and produce disease which
begins in the intestinal tract, or they may come in contact with scratches,
bites, or other wounds of the skin, mouth, and tongue, and produce in these
situations swellings or carbuncles. From such swellings the bacilli
penetrate into the blood and produce a general disease.
It has likewise been asserted that the disease may be transmitted by
various kinds of insects which carry the bacilli from the sick and
inoculate the healthy as they pierce the skin. When infection of the blood
takes place from the intestines the carbuncles may be absent. It has
already been stated that since anthrax spores live for several years, the
disease may be contracted in winter from feed gathered on permanently
infected fields.
The disease may appear sporadically, i. e., only one or several animals may
be infected while the rest of the herd remain well, or it may appear as an
epizootic attacking a large number at about the same time.
_Symptoms._--The symptoms in cattle vary considerably, according as the
disease begins in the skin, in the lungs, or in the intestines. They depend
also on the severity of the attack. Thus we may have what is called anthrax
peracutus or apoplectiform, when the animal dies very suddenly as if from
apoplexy. Such cases usually occur in the beginning of an outbreak. The
animal, without having shown any signs of disease, suddenly drops in the
pasture and dies in convulsions, or one apparently well at night is found
dead in the morning.
The second type (anthrax acutis), without any external swellings, is the
one most commonly observed in cattle. The disease begins with a high fever.
The temperature may reach 106∞ to 107∞ F. The pulse beats from 80 to 100 a
minute. Feeding and rumination are suspended. Chills and muscular tremors
may appear and the skin show uneven temperature. The ears and base of the
horns are cold, the coat staring. The animals are dull and stupid and
manifest great weakness.
To these symptoms others are added in the course of the disease. The
dullness may give way to great uneasiness, champing of the jaws, spasms of
the limbs, kicking and pawing the ground. The breathing may become labored.
The nostrils then dilate, the mouth is open, the head raised, and all
muscles of the chest are strained during breathing, while the visible
mucous membranes (nose, mouth, rectum, and vagina) become bluish. If the
disease has started in the bowels, there is much pain, as shown by the
moaning of the animal; the discharges, at first firm, become softer and
covered with serum, mucus, and blood.
As the disease approaches the fatal termination the weakness of the animal
increases. It leans against supports or lies down. Blood vessels may
rupture and give rise to spots of blood on the various mucous membranes and
bloody discharges from nose, mouth, rectum, and vagina. The urine not
infrequently contains blood (red water), and death ensues within one or two
days.
A third type of the disease (anthrax subacutus), which is rarely observed,
includes those cases in which the disease is more prolonged. It may last
from three to seven days and terminate fatally or end in recovery. In this
type, the symptoms are practically as described in the acute form, only
less marked.
In connection with these types of intestinal anthrax, swellings may appear
in different parts of the body under the skin, or the disease may start
from such a swelling, caused by the inoculation of anthrax spores in one of
the several different ways already described. If the disease begins in the
skin, it agrees in general with the subacute form in prolonged duration,
and it may occasionally terminate in recovery if the swellings are
thoroughly incised and treated.
_Lesions._--These swellings appear as edemas and carbuncles. The former are
doughy tumors of a more or less flattish form passing gradually into the
surrounding healthy tissue. As a rule, they are situated beneath the skin
in the fatty layer, and the skin itself is at first of healthy appearance,
so that they are often overlooked, especially when covered with a good coat
of hair. When they are cut open they are found to consist of a peculiar,
jellylike mass of a yellowish color and more or less stained with blood.
The carbuncles are firm, hot, tender swellings, which later become cool and
painless and undergo mortification. The edemas and carbuncles may also
appear in the mouth, pharynx, larynx, in the tongue, and in the rectum.
The bodies of cattle which have died of anthrax soon lose their rigidity
and become bloated, because decomposition sets in very rapidly. From the
mouth, nose, and anus bloodstained fluid flows in small quantities. When
such carcasses are opened and examined it is found that nearly all organs
are sprinkled with spots of blood or extravasations of various sizes. The
spleen is enlarged from two to five times, the pulp blackish and soft and
occasionally disintegrated. The blood is of tarry consistency, not firmly
coagulated, and blackish in color. In the abdomen, the thoracic cavity, and
in the pericardium, or bag surrounding the heart, more or less
blood-stained fluid is present. In addition to these characteristic signs,
the carbuncles and swellings under the skin, already described, will aid in
determining the true nature of the disease. The most reliable method of
diagnosis is the examination of the blood and tissues for anthrax bacilli,
which requires a trained bacteriologist. The cases of fatal anthrax number
from 70 to 90 per cent, and are usually more numerous at the first outbreak
of the disease.
_Differential diagnosis._--The diagnosis from blackleg may be made by
noting the subcutaneous swellings which appear upon the patient. Those of
blackleg are found to crackle under pressure with the finger, owing to the
presence of gas within the tissues, while the tumors of anthrax, being
caused by the pressure of serum, are entirely free from this quality and
have a somewhat doughy consistence. The tumors of blackleg are usually on
the shoulder or thigh and are not found so frequently about the neck and
side of the body as are the swellings of anthrax. The blood of animals dead
of blackleg is normal, and the spleen does not appear swollen or darkened,
as in those affected with anthrax. The chief differences between anthrax
and Texas fever are that the course of the former is more acute and the
blood of the animal is dark and of a tarlike consistence, while in the
latter it is thinner than normal. The presence of Texas-fever ticks on the
cattle would also lead one to suspect that disease in regions where cattle
are not immune from it.
_Treatment._--In cases which originate from external wounds, the swellings
should be opened freely by long incisions with a sharp knife and washed
several times daily with carbolic-acid solution (1 ounce to a quart of
water). Care should be taken to disinfect thoroughly any fluid discharge
that may follow the incision. When suppuration has set in the treatment
recommended in the chapter on wounds should be carried out.
In the treatment of animals showing symptoms of anthrax, the serum
recommended under the next heading of "Prevention" should be administered
in large doses. Animals showing only a high temperature with no other
symptoms of the disease should be given from 30 to 50 cubic centimeters of
the serum, but if the gravity of the disease is pronounced 100 cubic
centimeters should be administered. In most instances a drop in temperature
may be observed and a diminishing of the severity of the symptoms. At
times, however, a relapse occurs about the second or third day following
the serum injection, when it becomes necessary to administer another dose
of serum. It has been proved that animals affected with anthrax may recover
after injections of potent serum.
_Prevention._--In this disease prevention is the most important subject
demanding consideration. The various means to be suggested may be brought
under two heads: (1) The surroundings of the animal, and (2) preventive
inoculation.
(1) Surroundings.--What has already been stated of those conditions of the
pastures which are favorable to anthrax, after a little thought, will
suggest to most minds some of the preventive measures which may be of
service in reducing losses in anthrax localities. All that conduces to a
better state of the soil should be attempted. The State or Nation, by
appropriate engineering, should do its share in preventing frequent
inundations. If pools of stagnant water exist in the pastures, or if any
particular portions are known by experience to give rise to anthrax, they
should be fenced off. Efforts should likewise be made toward the proper
draining of swamp lands frequented by cattle. Sometimes it has been found
desirable to abandon for a season any infected or dangerous pastures. This
remedy can not be carried out by most farmers, and it is liable to extend
the infected territory. In some instances withdrawal of cattle from
pastures entirely and feeding them in stables is said to have reduced the
losses.
It is of the utmost importance that carcasses of animals which have died of
anthrax be properly disposed of, as every portion of such animal contains
the bacilli, ready to form spores when exposed to the air. Perhaps the
simplest means is to bury the carcasses deep, where they can not be exposed
by dogs or wild animals. It may be necessary to bury them on the pasture,
but it is better to remove them to places not frequented by susceptible
animals and to a point where drainage from the graves can not infect any
water supply.
If they are moved some distance it must be borne in mind that the ground
and all objects which have come in contact with the carcass should be
disinfected. This is best accomplished with chlorid of lime. For washing
utensils, etc., a 5 per cent solution may be prepared by adding 3 ounces to
2 quarts of water. This should be prepared fresh from the powder, and it is
but little trouble to have a small tin measure of known capacity to dip out
the powder, to be added to the water whenever necessary. The carcass and
the ground should be sprinkled with powdered chlorid, or, if this is not at
hand, an abundance of ordinary, unslaked lime should be used in its place.
The removal of carcasses to rendering establishments is always fraught with
danger, unless those who handle them are thoroughly aware of the danger of
scattering the virus by careless handling in wagons that are not tight. As
a rule, the persons in charge of such transfer have no training for this
important work, so that deep burial is to be preferred. Burning large
carcasses is not always feasible; it is, however, the most certain means of
destroying infectious material of any kind, and should be resorted to
whenever practicable and economical. All carcasses, whether buried,
rendered, or burned, should be disposed of unopened. When stables have
become infected they should be thoroughly cleaned out, and the solution of
chlorid of lime freely applied on floors and woodwork. The feed should be
carefully protected from contamination with the manure or other discharges
from the sick.