infection, or may evince itself in two or three days as the result of
artificial inoculation. Young milch cows are most susceptible to an attack,
but older cows, bulls, or young cattle are by no means immune. The attack
causes a slight rise in temperature, which is soon followed by the
appearance of reddened, inflamed areas, principally upon the teats and
udder, and at times on the abdominal skin or the skin of the inner surface
of the thighs. In a few cases the skin of the throat and jaws has been
found similarly involved. If the affected parts are examined on the second
day after the establishment of the inflammation numerous pale-red nodules
will be found, which gradually expand until, within a few days, they reach
a diameter of one-half inch or even larger. At this period the tops of the
nodules become transformed into vesicles which are depressed in the center
and contain a pale, serous fluid. They usually reach their maturity by the
tenth day of the course of the disease and are then the size of a bean.
From this time the contents of the vesicles become purulent, which requires
about three days, when the typical pox pustule is present, consisting of a
swelling with broad, reddened base, within which is an elevated, conical
abscess varying from the size of a pea to that of a hazelnut.
The course of the disease after the full maturity of the pustule is rapid
if outside interference has not caused a premature rupture of the small
abscess at the apex of the swelling. The pustules gradually become darker
colored and drier until nothing remains but a thick scab, which at last
falls off, leaving only a slight, whitish scar behind. The total duration
of the disease covers some 20 days in each animal, and owing to the slow
spread of the infection from animal to animal, many weeks may elapse before
a stable can be fully freed from it. The fallen scabs and crusts may retain
their contagious properties for several days when mixed with litter and
bedding upon the floor of the stable, and at any time during this period
they are capable of producing new outbreaks should fresh cattle be brought
into the stalls and thus come into actual contact with them. Again, the
pustules may appear, one after another, on a single animal, in which case
the duration of the disease is materially lengthened.
_Treatment._--In herds of cattle that regularly receive careful handling,
no special treatment will be found necessary beyond the application of
softening and disinfecting agents to such vesicles upon the teats as may
have become ruptured by the hands of the milker. Carbolized vaseline or
iodoform ointment will be found well suited to this work. In more
persistent cases it may be found desirable to use a milking tube in order
to prevent the repeated opening of the pustules during the operation of
milking. Washing the sores twice daily with a weak solution of zinc chlorid
(2-1/2 per cent solution) has been found to assist in checking the
inflammation and to cleanse and heal the parts by its germicidal action.
When the udder is hard, swollen, and painful, support it by a bandage and
foment frequently with hot water. If calves are allowed to suckle the cows
the pustules become confluent, and the ulcerations may extend up into the
teat, causing garget and ruining the whole quarter of the udder.
As young cows are most susceptible to variola, the milker must exercise
constant patience with these affected animals so long as their teats or
udders are sore and tender, else the patient may contract vicious habits
while resisting painful handling. The flow of milk is usually lessened as
soon as the fever becomes established, but is again normal with the return
of perfect health.
The practice of thorough cleanliness in handling or milking affected cattle
may, in many instances, prevent the dissemination of the trouble among the
healthy portion of the herd, but even the greatest care may prove
insufficient to check the spread until it has attacked each animal of the
herd in turn.
ACTINOMYCOSIS (LUMPY JAW)
[Pls. XXXIX-XLI.]
Actinomycosis, also known as lumpy jaw, big jaw, wooden tongue, etc., is a
chronic infectious disease characterized by the formation of peculiar
tumors in various regions of the body, more particularly the head, and is
due to the specific action of a certain fungus-like germ (actinomyces).
This fungus is an organism which occurs in the tissues in the form of
rosettes, and it has therefore been termed the "ray fungus." The disease is
not directly transmitted from one animal to another, but it seems apparent
that the fungus is conveyed into the tissues by various feedstuffs through
slight wounds of the mucous membrane of the mouth, decayed teeth, or during
the shedding of milk teeth. The ray fungus is found in nature vegetated on
grasses, on the awns of barley, the spears of oats, and on other grains.
Quantities of the fungi have been found between the vegetable fibers of
barley which had penetrated the gums of cattle and on the awns of grain
embedded in the tongues of cows.
Although actinomycotic tumors on cattle had been the object of study for
many years, it was not until 1877 that the constant presence of actinomyces
was pointed out by Bollinger, of Munich, and since that time considered the
cause. This fungus was observed in these tumors as early as 1860 by
Rivolta, and by others subsequently, without having been suspected as
causing them.
Since Bollinger's publication much work has been done, many observations
made, and many hitherto obscure disease processes 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 are all found to be 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 abundant or so few 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
(1/50 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 magnifying 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 radiating from the center of
the mass (see Pl. XXXIX, fig. 2), somewhat like a rosette. If the fungus is
crushed, the interior is found made up of bundles of very fine filaments,
which are probably continuous into the club-shaped bodies. The addition of
a dilute solution of caustic soda or potash greatly aids the examination,
as 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 exterior is incrusted in lime salts, which are dissolved by
adding some weak dilute acid, like acetic acid. Only by this procedure can
the fungus be definitely recognized when in a mummified condition.
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 permitted 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. Present knowledge
concerning the actinomyces growth indicates that it should be classified
with the higher bacteria or trichomycetes.
Whatever the situation of the disease caused by actinomyces may be, 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 actinomyces colonies are lodged in
the spaces or interstices formed by the meshwork 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-yellow 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 jaws, in the parotid
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, or 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 disease
seems by preference to attack certain parts. Thus in England actinomycosis
of the tongue is most prevalent. In Denmark the soft parts of the head are
most prone to disease, while in Russia the lips are the usual seat. In
certain parts of Germany actinomycotic tumors are most frequently
encountered in the throat region and in the jawbones.
A description of actinomycosis of the jaw (lumpy jaw) and of the tongue has
already been given in a previous chapter, 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, funguslike bodies covered with thin sloughs. Or the original
swelling, in place of enlarging in 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 membrane, where
the disease first appeared, and hang or project into the cavity of the
pharynx, either as pendulous masses with slender stems or as tumors with
broad bases. Their position may be such as to interfere with swallowing and
with breathing. In either case serious symptoms will soon appear.
The invasion of the bones of the jaws by actinomycosis must be regarded as
one of the most serious forms of the disease. (Pls. XXXIX, XL.) It may
start in the marrow of the bone and by a slow extension gradually undermine
the entire thickness of the bone itself. The growth may continue outward,
and after working its way through muscle and skin finally break through and
appear externally as stinking fungoid growths. The growth may at the same
time work its way inward and appear in the mouth. The disease may also
begin in the periosteum, or covering of the bone, and destroy the bone from
without inward.
Actinomycosis of the lungs is occasionally observed, and it is not
improbable that at times it has been mistaken for tuberculosis. The
actinomyces grains are, however, easily observed if the diseased tissue is
carefully examined. The changes in the lungs as they appear to the naked
eye vary considerably from case to case. Thus in one animal the lungs were
affected as in ordinary bronchopneumonia as to the location, extent, and
appearance of the disease process. The affected lobes had a dark-red flesh
appearance, with yellowish areas sprinkled in here and there. (See Pl. XLI,
figs. 1, 2.) These latter areas were the seat of multiplication of the
actinomyces fungus. In another case, of which only a small portion of the
lungs was sent to the laboratory, they were completely transformed into a
uniformly grayish mass, very soft and pulpy to the touch, and appearing
like very soft and moist dough. (Pl. XLI, fig. 3.) The actinomyces grains
were exceedingly abundant in this tissue, and appeared when the tissue was
incised as minute sulphur-yellow grains, densely sprinkled through the
tissue, which readily came away and adhered to the knife blade. In still
another case a portion of the lung tissue was converted into large, soft
masses from 1 to 3 inches in diameter, each partly inclosed in very dense
connective tissue. These soft, grayish-yellow masses likewise resembled
moist dough in their consistency, and the actinomyces grains, though
neither very distinct nor at all abundant, were easily fished out and
identified as such. A portion of this growth, which was as large as a
child's head, was converted into an abscess filled with creamy semiliquid
pus.
This case differed from the preceding in that all appearance of lung tissue
had disappeared from the diseased mass. Only on the exterior the lung
tissue could be recognized, although even there it had been largely
converted into very dense, whitish connective tissue inclosing the fungoid
growth. In the other case the external form of the lung and the shape and
outline of the lobules were preserved, but the lung tissue itself was not
recognizable as such. In the case first mentioned the changes were still
less marked, and actinomycosis would not have been suspected by a simple
inspection. These few illustrations suffice to show that actinomycosis of
the lungs may appear under quite different forms, and that the nature of
the disease can be accurately determined only by finding the fungus itself.
Rarely actinomycosis attacks the body externally in places other than the
head and neck. Crookshank describes the case of a bull in which the flank
was attacked and subsequently the scrotum became diseased. A large portion
of the skin of the flank was destroyed and covered with a leathery crust.
When this was pulled away the pus beneath it showed the actinomyces grains
to the naked eye.
Actinomycosis may also involve the udder, the spermatic cord of castrated
animals, the vagina, and, when it becomes generalized, the brain, liver,
spleen, and muscular tissue.
Actinomycosis may in some cases be confounded with tuberculosis. The
diagnosis does not offer any difficulties, since the presence of the
actinomyces fungus at once removes any existing doubts. As has already been
intimated, these grains, simulating sulphur balls, are visible to the naked
eye, and their nature is readily determined with the aid of a microscope.
The course of the disease is quite slow. As the tumors grow they may
interfere with the natural functions of the body. According to their
situation, mastication, rumination, or breathing may be interfered with,
and in this way the animal may become emaciated. Actinomycosis of the
jawbones leads to destruction of the teeth and impedes the movements
necessary to chewing the feed. Similarly, when the disease attacks the soft
parts of the head obstructions may arise in the mouth by an inward growth
of the tumor. If tumors exist in the pharynx they may partially obstruct
the movements necessary to breathing, or close the air passages and cause
partial suffocation. Actinomycosis of the tongue, in interfering with the
many and varied movements of this important organ, is also a serious
matter. There is no reason to suppose that the localized disease interferes
with the general health in any other way than indirectly until internal
organs, such as the lungs, become involved.
A very small proportion of the cases may recover spontaneously, the tumors
being encysted or undergoing calcification. In most cases the disease
yields readily to proper treatment, and about 75 per cent of the affected
animals may be cured.
_Prevention._--The question as to how and where animals take this disease
is one concerning which we are still in the stage of conjecture, because so
far we possess very little information concerning the life history of the
actinomyces itself. The quite unanimous view of all observers is that
animals become infected from the feed. The fungus is lodged upon the plants
and in some way enters the tissues of the head, the lungs, and the
digestive tract, where it sets up its peculiar activity. It is likewise
generally believed that the fungus is, as it were, inoculated into the
affected part. This inoculation is performed by the sharp and pointed parts
of plants which penetrate the mucous membrane and carry the fungus with
them. The disease is therefore inoculable rather than contagious. The mere
presence of the diseased animal will not give rise to disease in healthy
animals unless the actinomyces grains pass directly from the diseased into
some wound or abrasion of the healthy or else drop upon the feed which is
consumed by the healthy. Not only are these views deducible from clinical
observation, but they have been proved by the positive inoculation of
calves and smaller animals with actinomyces. The danger therefore of the
presence of actinomyces for healthy animals is a limited one. Nevertheless
an animal affected with this disease should not be allowed to go at large
or run with other animals. If the fungus is being scattered by discharging
growths we certainly can not state at this stage of our knowledge that
other animals may not be infected by such distribution, and we must assume,
until more positive information is at hand, that this actually occurs.
It is, however, the opinion of the majority of authorities that when
actinomycosis appears among a large number of animals they all contract it
in the same way from the feed. Much speculation has therefore arisen
whether any particular plant or group of plants is the source of the
infection and whether any special condition of the soil favors it. Very
little positive information is at hand on these questions. It would be very
desirable for those who live in localities where this disease is prevalent
to make statistical and other observations on the occurrence of the disease
with reference to the season of the year, the kind of feed, the nature of
the soil (whether swampy or dry, recently reclaimed, or cultivated for a
long time) upon which the animals are pastured or upon which the feed is
grown.
It is highly probable that such investigations will lead to an
understanding of the source of the fungus and the means for checking the
spread of the disease itself. Veterinarian Jensen, of Denmark, made some
observations upon an extensive outbreak of actinomycosis a number of years
ago which led him to infer that the animals were inoculated by eating
barley straw harvested from pieces of ground just reclaimed from the sea.
While the animals remained unaffected so long as they pastured on this
ground or ate the hay obtained from it, they became diseased after eating
the straw of cereals from the same territory. Others have found that cattle
grazing upon low pastures along the banks of streams and subject to
inundations are more prone to the disease. It has also been observed that
feed gathered from such grounds, even after prolonged drying, may give rise
to the disease. Actinomycosis is not infrequent in cattle in the Southwest
and is generally supposed to be the result of eating the prickly fruit of
the cactus plant, causing wounds of the mucous membrane and subsequent
infection with the parasite. Much additional information of a similar kind
must be forthcoming before the source and manner of infection in this
disease and its dependence upon external conditions will be known. It is
not at all improbable that they may vary considerably from place to place.
_Treatment._--Until recently this has been almost entirely surgical. When
the tumors are external and attached to soft parts only, an early removal
may lead to recovery. This, of course, can be undertaken only by a trained
veterinarian, especially as the various parts of the head and neck contain
important vessels, nerves, and ducts which should be injured as little as
possible in any operation. Unless the tumor is completely removed it will
reappear. Disease of the jawbones is at best a very serious matter and
treatment is liable to be of no avail.
In March, 1892, an important contribution to our knowledge of this subject
was made by Nocard, of the Alfort Veterinary School, in a communication to
the French Central Society of Veterinary Medicine. He showed clearly that
the actinomycosis of the tongue, a disease which appears to be quite common
in Germany, and is there known as "wooden tongue," could be quickly and
permanently cured by the administration of iodid of potassium. Nocard calls
attention to the success of Thomassen, of Utrecht, who recommended this
treatment so long ago as 1885, and who has since treated more than 80
cases, all of which have been cured. A French veterinarian, Godbille, has
used the same remedy in a number of cases of actinomycosis in the tongue,
all of which have been cured. Nocard also gives details of a case which was
cured by himself.
All the cases referred to were of actinomycosis of the tongue, and no one
appears to have attempted the cure of actinomycosis of the jaw until it was
undertaken by Nˆrgaard, of the Bureau of Animal Industry. In April, 1892,
he selected a young steer in fair condition which had a tumor on the jaw
measuring 15-1/2 inches in circumference and from which a discharge had
already been established. This animal was treated with iodid of potassium,
and the result was a complete cure.
The iodid of potassium is given in doses of 1-1/2 and 2-1/2 drams once a
day, dissolved in water, and administered as a drench. The dose should vary
somewhat with the size of the animal and with the effects that are
produced. If the dose is sufficiently large signs of iodism appear in the
course of a week or 10 days. The skin becomes scurfy, there is weeping from
the eyes, catarrh of the nose, and loss of appetite. When these symptoms
appear the medicine may be suspended for a few days and afterward resumed
in the same dose. The cure requires from three to six weeks' treatment.
Some animals, generally the ones which show no signs of iodism, do not
improve under treatment with iodid of potassium.
If there is no sign of improvement after the animals have been treated four
or five weeks, and the medicine has been given in as large doses as appear
desirable, it is an indication that the particular animal is not
susceptible to the curative effects of the drug, and the treatment may
therefore be abandoned.
It is not, however, advisable to administer iodid of potassium to milch
cows, as it will considerably reduce the milk secretion or stop it
altogether. Furthermore, a great part of the drug is excreted through the
milk, making the milk unfit for use. It should not be given to animals in
advanced pregnancy, as there is danger of producing abortion.
The best results are obtained by pushing the drug until its effect is seen.
The many tests to which this treatment has been subjected have proved, with
few exceptions, its specific curative value. In addition to this the tumor
should be painted externally with either the tincture of iodin or Lugol's
solution, or the drug should be injected subcutaneously into the tumor.
Godbille has given as much as 4 drams of potassium iodid in one day to a
steer, decreasing the dose one-fourth dram each day until the dose was
1-1/4 drams, which was maintained until the twelfth day of treatment, when
the animal appeared to be entirely cured.
Nocard gave the first day 1-1/2 drams in one dose to a cow; the second and
succeeding days a dose of 1 dram in the morning and evening, in each case
before feeding. This treatment was continued for 10 days, when the animal
was cured.