Actionomycosis - Bony Lump Jaw in Cattle
by Heather Smith Thomas
Bacteria are often present in the mouth of cattle, so anything that
punctures the mouth tissues may open the way for infection, possibly
leading to "lump jaw." According to Dr. Robert Cope, veterinarian
at Salmon, Idaho, there are two kinds of "lump jaw," caused
by two types of bacteria, that require different treatment.
Most common are soft tissue infections that are relatively easy to
treat by lancing and draining. Another type of lump is caused by infection
in the bone, and it is difficult to halt, says Cope. It usually results
in having to butcher the animal. Bony lump jaw tends to occur most
often in young cattle, two or three years of age.
Both types of lump jaw begin in the same manner. A break in the tissue
allows bacteria to enter. A sharp seed or sharp object in the feed
may poke the side of the mouth. Ulcers caused by BVD virus can open
the way for bacteria, which can then enter from feed or soil. Grazing
cattle may pull plants up by the roots, eating dirt clinging to the
roots. Cattle fed on the ground may pick up dirt or mud eating the
The most common form of lump jaw is caused by a bacteria -- Actinobacillus
-- in the soft tissues, forming an abscess along the lower jaw. "Actinobacillus
is a Gram-negative bacteria routinely present in the soil in many
areas," says Cope. The lump may be hard or soft, but can be moved
around if you press it firmly with your hand; it is not attached to
A different bacteria, Actinomyces bovis (a gram positive bacteria
that also lives in soil), can infect the mouth and cause bony lump
jaw. The condition is called Actinomycosis. This bacteria enters a
wound or dental socket in the mouth the same way, says Cope, but infects
the bone if the break in the tissues penetrates deeply.
The infection gets going in the upper or lower jaw, creating a painless
bony enlargement, usually at the level of the central molars. In rare
cases it involves tissues of mouth and throat if lacerations permit
entrance of bacteria. Bony lump jaw occurs only sporadically, but
is a serious condition because of poor response to treatment. A general
enlargement on the lower jawbone may appear as a thickening of the
lower edge of the bone (with most of the enlargement between the two
sides of the jaw); these lumps may not be observed until they are
quite large and too extensive for treatment to be effective. The more
common protrusions on the side of the bone are more easily seen.
|The lump on this three-year-old
cow began developing six months earlier. It has now broken through
Some swellings enlarge swiftly in a few weeks, while others grow slowly
over several months. The bony swellings are very hard and quite immobile.
You can't move the lump around with your hand because it is part of
the bone. There is no affect on the animal's health at first; this
infection does not create illness. In later stages the area may be
painful and interfere with chewing. The lump may break through the
skin eventually and discharge through one or more openings, oozing
a little pus or some sticky honey-like fluid containing tiny hard
yellow granules, says Cope.
Lancing is of no value, since the lump is composed
of infected bone and cannot be drained. The oozing area may heal over,
only to break out again. "Attempting to drain this lesion is
fruitless at best," says Cope, "and can be harmful. Opening
this area to the outside may allow other disease organisms to enter,
resulting in further secondary infection. When you see an animal with
a swollen jaw or lump, feel the jaw and try to move the lump--to tell
the two types of diseases apart." A bony lump should never be
Teeth in the affected jawbone may become misaligned and cause pain
when chewing. This makes it hard for the animal to eat and can result
in losing weight. In severe cases, the infection spreads to softer
tissues and involves the muscles and lining of the throat, interfering
with the animal's ability to belch and chew its cud. If swelling becomes
extensive, it can interfere with breathing. The animal may become
so thin that humane destruction is necessary, though it may take a
year to get this bad. If the infection spreads to the esophagus and
stomach, digestion becomes impaired, causing diarrhea (passing undigested
food particles on through) or bloat.
|This cow is receiving
sodium iodide intravenously. Some lumps reduce in size, but may
not go away completely.
A bony lump is a bone infection, and "must be treated from the
inside out, via the bloodstream that serves the bone," says Cope.
Usual treatment is sodium iodide into the jugular vein, repeated in
10 days. Even this treatment is not always successful in halting the
bone infection. The lump may stop growing for awhile and you can get
a feedlot animal marketed, or you might get one or two more calves
from a cow, then it starts again.
Iodides given intravenously may halt the infection if given early
(before the lump gets large) but many cases are stubborn, says Cope.
Some lumps reduce in size once infection is stopped, but never go
away completely. He says abortion may occasionally occur after iodide
treatment if a cow is pregnant. "We often try to postpone treatment
of bony lump jaw during late pregnancy, hoping to save the cow and
calf both. But if the cow is going downhill or not due to calve for
some time, we will usually treat the cow and take our chances with
the possibility of abortion." ©