Actinomycosis and actinobacillosis treatment in cattle

28/02/2023

Sodium iodide is the treatment of choice in ruminants
The goal of treatment for actinomycosis is to kill the bacteria and stop the spread of the lesion. However, the size of the hard mass will usually not regress significantly. Sodium iodide is the treatment of choice in ruminant actinomycosis. Intravenous sodium iodide (70 mg/kg of a 10%–20% solution) is given once and then repeated several times at 7–10 day intervals. If clinical signs of iodine toxicity develop (including dandruff, diarrhea, anorexia, coughing, and excessive lacrimation), iodine administration should be discontinued or treatments given at greater intervals. Sodium iodide has been shown to be safe for use in pregnant cows and presents little risk of abortion. Concurrent administration of antimicrobials, including penicillin, florfenicol, or oxytetracycline, is recommended.

04/02/2023

04/02/2023

06/09/2022

Sodium iodide is the treatment of choice in ruminant actinobacillosis. Intravenous sodium iodide (70 mg/kg of a 10% to 20% solution) is given once and then repeated 1–2 times at 7- to 10-day intervals. If clinical signs of iodine toxicity develop (including dandruff, diarrhea, anorexia, coughing, and excessive lacrimation), iodine administration should be discontinued. Clinical improvement is often seen within 48 hours of therapy, and treatment is usually successful when only the tongue is involved. Systemic antibacterial agents, such as ceftiofur, penicillin, ampicillin, florfenicol, and tetracyclines may be effective and are primarily recommended in severe cases of actinobacillosis or in cases refractory to sodium iodide therapy. Surgical debulking of lesions, especially if they interfere with airflow, may be useful. This is particularly true when large granulomatous masses are present that do not respond to medical therapy.

06/09/2022

The primary lesion associated with A lignieresii infection in cattle is a very hard, diffusely swollen tongue. This leads to excessive salivation, the inability to prehend food normally, and sometimes a visibly enlarged tongue that protrudes from the mouth. On palpation, the tongue will feel very hard and painful. This form of actinobacillosis is found worldwide but is sporadic and thus difficult to prevent. Herd outbreaks are also possible and are generally associated with the consumption of coarse, abrasive feeds that predispose to formation of lesions in the mouth.
A seminis is an occasional cause of polyarthritis in young lambs and epididymitis in adult rams. A ureae has caused upper respiratory tract infections in humans and abortions in pigs. In addition, A actinoides has occasionally been associated with suppurative pneumonia in calves and seminal vesiculitis in bulls.

06/09/2022

The organism may also cause pyogranulomatous lesions in soft tissues associated with the head, neck, limbs, and occasionally the lungs, pleura, udder, and subcutaneous tissue. The organism is part of the normal mucosal flora of the upper GI tract and causes disease when it gains access to adjacent soft tissue via penetrating wounds. It causes localized infections and can spread via the lymphatics to other tissues.

06/09/2022

Actinobacillosis is caused by several species of gram-negative coccobacilli of the genus Actinobacillus. Clinical signs vary, depending on the specific bacteria and the animal species they infect. Diagnosis can be confirmed by culture, PCR, or ELISA of tissue samples to identify the bacteria. Antibiotics are the usual treatment in swine and horses. Sodium iodide is used in ruminants, although antibiotics or surgical debulking may be required in severe or refractory cases.

06/09/2022

Actinobacillosis in cattle typically involves the tongue, causing an indurative pyogranulomatous glossitis referred to as “wooden tongue.”23,29 The involvement of other organs, generally the skin or lymph nodes, has been regarded as atypical or cutaneous actinobacillosis

06/09/2022

Bovine actinobacillosis is typically characterized by pyogranulomatous glossitis (wooden tongue). The involvement of other tissues, generally the skin or lymph nodes, has been regarded as atypical or cutaneous. We describe herein 2 outbreaks of actinobacillosis affecting primarily the lymph nodes of the head and neck. The disease affected 40 of 540 lactating cows in a dairy herd, and 5 of 335 two-y-old steers in a beef herd. Multiple or single, occasionally ulcerated nodules were observed in the region of the mandible, neck, and shoulder, including the parotid, submandibular, retropharyngeal, and prescapular lymph nodes. The histologic lesions were multifocal pyogranulomatous lymphadenitis, dermatitis, and cellulitis with Splendore–Hoeppli material. One steer had an exophytic pyogranuloma in the gingiva and another died because of ruminal tympany secondary to oropharyngeal and esophageal obstruction by a pyogranulomatous mass. Actinobacillus lignieresii was isolated from the lesions and identified by amplification, sequencing, and analysis of the 16S ribosomal (r)DNA gene. Seven of 8 cows recovered after treatment with sodium iodide. Lymphatic actinobacillosis is a frequent disease in Uruguay, southern Brazil, and Argentina. Morbidity is 1–50%; mortality is

19/08/2022

15/08/2022

Clinical Findings
A bovis is part of the normal oral flora of ruminants. Disease is seen when A bovis is introduced to underlying soft tissue via penetrating wounds of the oral mucosa from wire or coarse hay or sticks. Involvement of adjacent bone frequently results in facial distortion, loose teeth (making chewing difficult), and dyspnea from swelling into the nasal cavity. Any part of the bovine can be affected, but the alveoli around the roots of the cheek teeth are frequently involved. The primary lesion appears as a slow-growing, firm mass that is attached to, or is part of, the mandible. In some cases, ulceration with or without fistulous tracts form, and drainage of purulent exudate may occur.
Lumpy jaw, cow
A suis has classically caused pyogranulomatous porcine mastitis, characterized by small abscesses containing thick, yellow pus surrounded by a wide zone of dense connective tissue. Yellow “sulfur granules” may be scattered throughout the pus, as in A bovis in cattle. Chronic, deep-seated abscesses may fistulate. Sows may also develop ventral subcutaneous granulomatous lesions, and occasional pyogranulomatous infections develop in lungs, spleen, kidneys, and other organs. More recently it was discovered that A suis isolates are likely more correctly classified as A denticolens, which has also been reported to cause mandibular lymphadenopathy in horses with fever, nasal discharge, and depression. Thus A denticolens is a pathogen in a broad range of animals.
A hordeovulneris is a rare cause of canine actinomycosis that can present with either localized abscesses or systemic infections, such as pyogranulomatous pleuritis, peritonitis, visceral abscesses, and septic arthritis. A common predisposing factor is the presence of tissue-migrating foxtail grass (Hordeum spp) particles, and the primary route of infection appears to be via inhalation of the bacteria.
A viscosus causes cutaneous actinomycosis in dogs, which appears as localized subcutaneous abscesses. These usually occur secondary to perforating injuries caused by bite wounds or foreign bodies. The most common sites for abscesses are the head, neck, thorax, and abdomen. Pneumonia and pyothorax have also been described with A viscosus, along with rare cases of pyogranulomatous meningoencephalitis.

05/08/2022

nomyces bovis, a normal resident in the mouth. Establishment of infection may follow tooth eruption in maturing cattle or damage to the oral mucosa from coarse and prickly feeds.
Infection is accompanied by slow and progressive swelling of the affected area due to inflammation, necrosis and deposition of new bone. In time, infection breaks out through sinuses in overlying skin, draining sticky pus with yellow gritty granules. Local lymph nodes are unaffected. The bony distortion interferes with chewing and weight gain.
Lumpy jaw is a sporadic disease affecting small numbers of animals. The disease may be difficult to detect until advanced and associated with obvious facial distortion or other clinical signs. Exclusion from the export process will require specific inspection of both sides of the head. Identifying affected animals is important in case they are rejected at destination.
CLINICAL SIGNS AND DIAGNOSIS
Affected areas in the upper or lower jaw will be associated with a hard, immovable swelling. Discharging skin sinuses, drooling and weight loss may be present.
Laboratory confirmation in live animals requires smears of pus from deep within the lesion. Confirmation in dead animals should also include tissue sections in buffered formalin for histology.
Differential diagnoses include woody tongue, oral foreign bodies, jaw bone fracture, subcutaneous abscess and food impacted in the cheek recess behind broken teeth or missing teeth.
TREATMENT
Lumpy jaw is difficult to treat successfully. In valuable animals with early lesions, extended treatment with ceftiofur, oxytetracyclines and/or sodium iodide may be attempted, but results are uncertain and relapse may occur. Strong consideration should be given to salvage slaughter of affected animals before weight loss and the risk of condemnation occur.
PREVENTION
Special preventative measures are not warranted due to the sporadic occurrence of the disease. Awareness of the condition, and systems for early detection and exclusion from the livestock export process are the main preventive strategies.

17/11/2021

Actinomyces are a Gram-positive anaerobic type of bacteria. At one time, due to their fungus-like branched network of hyphae, they were assumed to be a type of fungus. They play an important role in soil ecology by producing enzymes that help degrade organic plant materials.

The bacteria are known for causing disease in humans and animals and are one of most common causes of infections following dental procedures as the bacteria can be found in the nose and throat of many people. The infectious bacterial disease caused by Actinomyces species is known as actinomycosis.

17/11/2021

Actinomycosis is a rare, infectious disease in which bacteria spread from one part of the body to another through body tissues. Over time, it can result in linked abscesses, pain, and inflammation.

It can affect the skin or deeper areas within the body and sometimes the blood.

Many people have actinomycosis bacteria in their body, but the bacteria usually stay in one place and do not cause disease in healthy tissues.

If damage occurs in the area around where the bacteria live, due to injury or trauma, the bacteria can move to other areas.

As the condition progresses, the deep tissue can become inflamed and pus-filled. It can result in abscesses, tissue death, cavities, and masses of fibrous tissue in the body.

According to an article published in Clinical Microbiology Reviews, infection is not contagious, because these bacteria cannot survive outside the human body and infections typically occur after tissue damage.

06/06/2021

Actinomycosis is a rare, infectious disease in which bacteria spread from one part of the body to another through body tissues. Over time, it can result in linked abscesses, pain, and inflammation.
It can affect the skin or deeper areas within the body and sometimes the blood.
Many people have actinomycosis bacteria in their body, but the bacteria usually stay in one place and do not cause disease in healthy tissues.
If damage occurs in the area around where the bacteria live, due to injury or trauma, the bacteria can move to other areas.
As the condition progresses, the deep tissue can become inflamed and pus-filled. It can result in abscesses, tissue death, cavities, and masses of fibrous tissue in the body.
According to an article published in Clinical Microbiology Reviews, infection is not contagious, because these bacteria cannot survive outside the human body and infections typically occur after tissue damage.
Find out more about actinomycosis and the treatment options available.
Causes
Actinomycosis is a rare infection that can spread through body tissues.
Actinomycosis happens when the Actinomyces species of bacteria spread through the body because of tissue damage.
Most people have Actinomyces bacteria in the lining of the mouth, throat, digestive tract, and urinary tract, and it is present in the female ge***al tract.
The bacteria live harmlessly in the body, but they become dangerous if they spread out of their usual environment.
This can happen as a result of:
disease
tissue damage due, for example, to injury or surgery
If something sharp pierces the internal body tissues, such as a fish bone in the esophagus, the bacteria can spread.
Actinomycosis can also happen if there is tooth decay or gum disease.
As the infection progresses, painful abscesses can form and grow in size. This usually takes several months.
Sometimes, it can be so severe that the infection enters the surrounding bone and muscle. In severe cases, the skin can break open, leaking large amounts of pus.
Actinomyces bacteria are anaerobic. This means they live deep inside body tissues, where oxygen levels are very low.
This type of bacterial infection can be harder to diagnose and often takes longer to treat than other types.
Types
Actinomycosis can affect almost any part of the human body.
Jaw or mouth
A mouth or gum infection can lead to actinomycosis.
Orocervicofacial actinomycosis affects the mouth, jaw, or neck. The bacteria that cause this infection typically live in dental plaque.
It can result from:
dental problems, such as decay and poor oral hygiene
trauma to the mouth or face, if particles of dental plaque enter the mucous membrane
It can also develop after a dental procedure.
The person may notice the infection within hours of injury, or it may take several weeks for symptoms to appear.
There may be:
a hard, painful swelling in the soft tissue of the mouth, known as a “woody” fibrosis
an abscess
This is the most common form of infection caused by Actinomyces. It accounts for 50 percent of all cases, according to an article published in Antimicrobe.
Lungs
Thoracic actinomycosis can develop in the airways and lungs.
It often happens when people breathe bacteria from the mouth and throat into the lungs.
The symptoms affect the lungs first. Then they can extend to the area around the lungs, the chest cavity, and the upper spine.
The person may experience:
weakness
a fever
a productive cough
severe weight loss
Abdomen
Abdominal actinomycosis occurs in the abdomen, but it can affect any part of the digestive system, from the food pipe to the a**s.
It can happen after an appendix bursts, or after a person has surgery for appendicitis.
The individual may have:
abscesses
persistent fever
pain
diarrhea or constipation
pus that appears through the skin
The type of infection can spread.
It can reach
the pericardium, which is the sac around the heart
the liver or spleen
Sometimes, it can go on to affect the pelvis.
Pelvis
Pelvic actinomycosis can spread from the va**na to other areas in the pelvis. Certain gynecological procedures can increase the risk.
Sometimes, using an intrauterine device (IUD) for birth control for a long time can increase the chance of developing this type of infection.
If this occurs, the individual may notice:
va**nal discharge
pain or a lump or swelling in the lower abdomen or pelvis
The American College of Obstetricians and Gynecologists (ACOG) note that around 7 percent of women with an IUD have Actinomyces bacteria, usually without symptoms. Tests usually find the bacteria by chance.
ACOG guidelines published in 2016 recommend that the IUD can remain in place for its recommended time of use. No treatment is necessary.
However, people should not leave an IUD in place longer than recommended. Depending on the type, this may be 5 or 10 years.
The bacteria can also cause abscesses in the ovaries and fallopian tubes. These can lead to complications with other organs within the abdomen and pelvis.
Anyone with an IUD who experiences pain or discomfort or signs of a fever should see a doctor.
Rare types of actinomycosis
Without treatment, actinomycosis can affect the central nervous system (CNS). This is rare.
It can happen directly due to a lesion on the neck or face, or it may spread from elsewhere. It can lead to a brain abscess, causing headaches and neurological symptoms.
Another rare type affects the skin and bones, usually when the infection spreads from deeper tissues.
Symptoms
Actinomycosis can take a variety of forms. It can also resemble other infections, and even neoplasms, or tumors.
It typically features a number of small, interlinked abscesses.
The symptoms depend on the type of actinomycosis, but they may include:
swelling and inflammation at the site of the infection
tissue damage and scar tissue
abscesses, or pus-filled lumps
small holes or tunnels in tissue called fistulas that can leak a kind of lumpy pus
The severity of symptoms mostly depends on where in the body the infection occurs
There may be pain and fever, along with body aches, fatigue and a general feeling of being unwell.
Diagnosis
Lab tests of sputum, pus, or tissue may be necessary to diagnose actinomycosis.
To diagnose actinomycosis, a doctor may take a sample of sputum, pus, or tissue to send for microscopic investigation in a laboratory. Sometimes, the laboratory will make a culture of the bacteria.
If the infection is present, the pus or tissue will usually contain yellow sulfur granules.
In some cases, the abscess may resemble a cancerous growth. Lesions in the lungs can cause symptoms similar to cancer or tuberculosis (TB).
It is important to rule out other causes of similar symptoms.
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Treatment
Actinomycosis can persist for a long time. Long-term treatment with antibiotics, such as penicillin, is common. It may last from 8 weeks to over 12 months.
In some cases, a surgeon may drain an abscess or remove an infected part. After this, the person may need a 3-month course of antibiotics to resolve the problem.
Takeaway
Actinomycosis develops slowly, but it can have a serious impact on a person’s health. It is important to get early treatment if it occurs.
Authors of a study published in 2014 suggest the following ways of reducing the risk of developing actinomycosis:
avoiding alcohol abuse
maintaining good overall health
keeping long-term medical conditions under control
practicing good dental and oral hygiene
In countries with good access to antibiotics and dental services, the chance of having actinomycosis tends to be lower.

06/06/2021

Actinomycosis is a rare chronic disease caused by Actinomyces spp., anaerobic Gram-positive bacteria that normally colonize the human mouth and digestive and ge***al tracts. Physicians must be aware of typical clinical presentations (such as cervicofacial actinomycosis following dental focus of infection, pelvic actinomycosis in women with an intrauterine device, and pulmonary actinomycosis in smokers with poor dental hygiene), but also that actinomycosis may mimic the malignancy process in various anatomical sites. Bacterial cultures and pathology are the cornerstone of diagnosis, but particular conditions are required in order to get the correct diagnosis. Prolonged bacterial cultures in anaerobic conditions are necessary to identify the bacterium and typical microscopic findings include necrosis with yellowish sulfur granules and filamentous Gram-positive fungal-like pathogens. Patients with actinomycosis require prolonged (6- to 12-month) high doses (to facilitate the drug pe*******on in abscess and in infected tissues) of penicillin G or amoxicillin, but the duration of antimicrobial therapy could probably be shortened to 3 months in patients in whom optimal surgical resection of infected tissues has been performed. Preventive measures, such as reduction of alcohol abuse and improvement of dental hygiene, may limit occurrence of pulmonary, cervicofacial, and central nervous system actinomycosis. In women, intrauterine devices must be changed every 5 years in order to limit the occurrence of pelvic actinomycosis.

Keywords: Actinomyces spp., sulfur granule, osteomyelitis, lumpy jaw syndrome

Introduction

Actinomycosis is an infrequent invasive bacterial disease that has been recognized for over a century. Actinomyces spp. are filamentous Gram-positive bacilli, mainly belonging to the human commensal flora of the oropharynx, gastrointestinal tract, and uroge***al tract. To date, multiple different clinical features of actinomycosis have been described, as various anatomical sites (such as face, bone and joint, respiratory tract, genitourinary tract, digestive tract, central nervous system, skin, and soft tissue structures) can be affected. Of note, in any site, actinomycosis frequently mimics malignancy, tuberculosis, or nocardiosis, as it spreads continuously and progressively, and often forms a cold abscess.1–3

In this review, we aim to describe: 1) the overview of the different species of Actinomyces; 2) their involvement in different clinical features with illustrative cases; and 3) key elements for the diagnosis, ie, bacterial cultures and pathology; and 4) current and emerging treatment options.

06/06/2021

Actinomyces are gram-positive, anaerobic bacteria that cause disease primarily in cattle and swine but also occasionally in other animals. Lumpy jaw is a localized, chronic, progressive, granulomatous abscess that most frequently involves the mandible, the maxillae, or other bony tissues in the head. Presumptive diagnosis is often based on clinical signs. The diagnosis can be confirmed by culture of the organism from the lesion; however, this requires anaerobic conditions and is frequently negative. The goal of treatment for actinomycosis is to kill the bacteria and stop the spread of the lesion.
Actinomycosis, cow
Actinomycosis, cow
COURTESY OF DR. GEOFFREY SMITH.

Members of the genus Actinomycesare gram-positive, anaerobic, non-acid-fast rods, many of which are filamentous or branching. Branches are 1 mcm in diameter. Although they are normal flora of the oral and nasopharyngeal membranes, several species are associated with diseases in animals.

A bovis is the etiologic agent of lumpy jaw in cattle. It has also been isolated from nodular abscesses in the lungs of cattle and infrequently from infections in sheep, pigs, dogs, and other mammals, including chronic fistulous withers and chronic poll evil in horses. Lumpy jaw is a localized, chronic, progressive, granulomatous abscess that most frequently involves the mandible, the maxillae, or other bony tissues in the head.

A actinoides is occasionally found as a secondary invader in enzootic pneumonia of calves and seminal vasculitis in bulls. A israelii is primarily associated with chronic granulomatous infections in humans but has also been isolated rarely from pyogranulomatous lesions in pigs and cattle. Treatment involves surgical debridement and administration of penicillin. A naeslundii has been isolated from suppurative infections in several animal species, the most common being aborted porcine fetuses.

Clinical Findings
A bovis is part of the normal oral flora of ruminants. Disease is seen when A bovis is introduced to underlying soft tissue via penetrating wounds of the oral mucosa from wire or coarse hay or sticks. Involvement of adjacent bone frequently results in facial distortion, loose teeth (making chewing difficult), and dyspnea from swelling into the nasal cavity. Any part of the bovine can be affected, but the alveoli around the roots of the cheek teeth are frequently involved. The primary lesion appears as a slow-growing, firm mass that is attached to, or is part of, the mandible. In some cases, ulceration with or without fistulous tracts form, and drainage of purulent exudate may occur.

Lumpy jaw, cow
Lumpy jaw, cow
COURTESY OF DR. JOHN PRESCOTT.

A suis has classically caused pyogranulomatous porcine mastitis, characterized by small abscesses containing thick, yellow pus surrounded by a wide zone of dense connective tissue. Yellow “sulfur granules” may be scattered throughout the pus, as in A bovis in cattle. Chronic, deep-seated abscesses may fistulate. Sows may also develop ventral subcutaneous granulomatous lesions, and occasional pyogranulomatous infections develop in lungs, spleen, kidneys, and other organs. More recently it was discovered that A suis isolates are likely more correctly classified as A denticolens, which has also been reported to cause mandibular lymphadenopathy in horses with fever, nasal discharge, and depression. Thus A denticolens is a pathogen in a broad range of animals.

A hordeovulneris is a rare cause of canine actinomycosis that can present with either localized abscesses or systemic infections, such as pyogranulomatous pleuritis, peritonitis, visceral abscesses, and septic arthritis. A common predisposing factor is the presence of tissue-migrating foxtail grass (Hordeum spp) particles, and the primary route of infection appears to be via inhalation of the bacteria.

A viscosus causes cutaneous actinomycosis in dogs, which appears as localized subcutaneous abscesses. These usually occur secondary to perforating injuries caused by bite wounds or foreign bodies. The most common sites for abscesses are the head, neck, thorax, and abdomen. Pneumonia and pyothorax have also been described with A viscosus, along with rare cases of pyogranulomatous meningoencephalitis.

Diagnosis
Diagnosis can be confirmed by culture, but false negatives are frequent
Actinomyces bovis, Gram-stained smear
Actinomyces bovis, Gram-stained smear
COURTESY OF DR. JOHN PRESCOTT.

Actinomycosis in cattle, radiograph
Actinomycosis in cattle, radiograph
COURTESY OF DR. GEOFFREY SMITH.

Presumptive diagnosis of actinomycosis is often based on clinical signs. The diagnosis can be confirmed by culture of the organism from the lesion, but this requires anaerobic conditions and is frequently negative. Cytology is useful because a Gram stain of purulent material will reveal gram-positive, club-shaped rods and filaments (sulfur granules). Radiology of the head is also useful; the primary radiographic lesion consists of multiple central radiolucent areas of osteomyelitis surrounded by periosteal new bone and fibrous tissue. As a last resort, a biopsy sample can be taken with a trephine and submitted for histopathology. In canine actinomycosis, history and clinical signs may contribute to the diagnosis, but demonstration of the causative agent by Gram stain and bacteriologic culture is necessary for confirmation of etiology. With cutaneous actinomycosis, soft, grayish-white granules are frequently visible in the pus or exudate. Cytology (of pus or pleural fluid) is quite useful and will reveal gram-positive, filamentous organisms.

Treatment
Sodium iodide is the treatment of choice in ruminants
The goal of treatment for actinomycosis is to kill the bacteria and stop the spread of the lesion. However, the size of the hard mass will usually not regress significantly. Sodium iodide is the treatment of choice in ruminant actinomycosis. Intravenous sodium iodide (70 mg/kg of a 10%–20% solution) is given once and then repeated several times at 7–10 day intervals. If clinical signs of iodine toxicity develop (including dandruff, diarrhea, anorexia, coughing, and excessive lacrimation), iodine administration should be discontinued or treatments given at greater intervals. Sodium iodide has been shown to be safe for use in pregnant cows and presents little risk of abortion. Concurrent administration of antimicrobials, including penicillin, florfenicol, or oxytetracycline, is recommended.

Treatment of A suis (A denticolens) infections in pigs is rarely successful, primarily due to the inability of an antibacterial agent to pe*****te the infected tissue. Infected tissue may be surgically removed to salvage sows for slaughter.

In dogs with A hordeovulneris, treatment includes surgical debridement and/or longterm treatment with penicillin, cephalosporins or sulfonamides. Pyothorax is frequently seen in canine actinomycosis, and requires repeated drainage of the chest in addition to antimicrobial therapy. Treatment of pyothorax due to A viscosus with penicillin, sulfonamides, or cephalosporins may be successful if begun early in the clinical course. A successful outcome is more likely with cutaneous infections, which should also be treated with the same antimicrobials.

Prevention
Because A bovis is part of the normal oral flora in ruminants, control focuses on the avoiding of coarse, stemmy feeds or feeds with plant awns that might damage the mucosal epithelium. When multiple cases occur in a herd, it is not from the contagious nature of the pathogen but from the widespread exposure to a risk factor (ie, coarse feed).

Key Points
Actinomyces bovis is the etiologic cause of lumpy jaw in cattle.
Intravenous sodium iodide is the recommended treatment in ruminants, although prognosis is guarded.
A suis (now A denticolens) causes mastitis as well as subcutaneous granulomatous lesions in sows, and treatment is rarely successful.
A hordeovulneris and A viscosus cause disease in dogs characterized by skin lesions, pleuritis, peritonitis, and/or internal abscesses.