Rhodococcus, Clostridium, Actinomyces, Dermatophilus Flashcards
C. novyi causes which disease in livestock?
Which tissue is affected?
Venous congestion or “black disease”
Liver and hepatic lymph
How are are animals infected by members of the genus Clostridium?
By wound infection or ingestion of endospores
What does C. difficile cause in companion animals?
Disruption of the normal intestinal microflora leading to diarrhea
What other measures can be used to control Rhodococcus equi infections?
Dust control
Remove foals from contaminated grounds or pasture
What disease patterns in large ruminants are caused by members of the genus Actinomyces?
Osteomyelitis (“lumpy jaw”
Epidermitis
Which speices of Clostridium causes gas gangrene?
What else can it cause in companion animals?
C. perfringes
Enterotoxemia
What disease patterns in pigs are caused by members of the genus Actinomyces?
Mastitis, pnuemonia, abortion, epidermitis
How are exotoxins produced by members of the genus Clostridium classified?
Histotoxic or neurotoxic exotoxins
What disease does Rhodococcus equi normally cause?
Foal pneumonia
Adult horses can also be affected
What disease pattern does C. botulinum cause?
Flaccid paralysis
C. chauvoei causes which disease in livestock?
myositits
“blackleg”
How are Clostridium infections treated and controlled?
Antibiotics (penicillin or tetracycline)
Antitoxin (antisera or purified Ig)
Vaccination (cattle and horses)
C. haemolyticium causes which disease in livestock?
Which tissue is affected?
hemoglobinuria or “red water”
Liver and hepatic lymph
What disease patterns in horses are caused by members of the genus Actinomyces?
Bursitis (“poll evil” or “fistulous withers”)
Epidermitis
What disease patterns in ruminants are caused by members of the genus Dermatophilus?
Rain scald, strawberry foot rot, lumpy wool
What disease pattern does C. tetani cause?
Continuous to transitiory spastic (stiff) paralysis
Which species should be annually vaccinated against histotoxic Clostridium?
How many species does the vaccine protect against?
Cattle. They should also be vaccinated before giving birth.
Seven
Does an animal have to be exposed to either C. tetani or C. botulinum to develop disease?
No, they can be exposed to just the exotoxins in the environment
What is the antibiotic of choice to treat Rhodococcus equi?
Which class of antibiotics should be avoided?
Erythromycin+rifampin
Avoid beta-lactams
C. piliforme causes which disease in livestock?
“Tyzzer’s” liver necrosis
What disease patterns in small ruminants are caused by members of the genus Actinomyces?
Epidermitis
What general disease patterns are casued by histotoxic members of the genus Clostridium?
Enterotoxemia and septicemia
(can include gastritis, hemorrhagic enteritis, cerebral hemorrhage, etc.)
How are Actinomyces and Dermatophilus infections treated and controlled?
Drain abcesses, topical/systemic iodine
Antibiotics
Provide shelter and grooming
Is Rhodococcus equi normally found among a horse’s microbiota?
No. It normally lives in soil and horses can become infected when they inhale contaminated dust.
Which antibiotics are commonly used to treat Actinomyces and Dermatophilus infections?
What is the first choice?
First choice- penicillin or ampicillin
Others- rifampin, macrolides, tetracycline
What disease patterns in dogs and cats are caused by members of the genus Actinomyces?
Wound infection (associated with grass awns)
Epidermitis
How is the morphology of Actinomyces described?
Branching, filamentous
