E2 Genus Mycobacteria Flashcards
What is special about the staining of Mycobacteria?
Acid-fast
= unique outer membrane
= NOT capsule
What is the Gram stain of Mycobacteria?
Gram (+)
Rods!
What is unique about the growth of Mycobacteria?
VERY slow
What special component do Mycobacteria have in their cell wall?
Mycolic acid
How do Mycobacteria avoid death by phagocytosis
Blocks acidification of phagolysosome
What kind of lesions are caused by Mycobacteria?
Granulomatous tubercles
What is Mycobacteria bovis?
Bovine TB
ZOONOTIC
Affects many species
How long before clinical signs appear of infection with Mycobacteria bovis?
1-5 years!
What is the definitive diagnosis for Mycobacteria bovis?
Culture
but PCR is useful
after TB skin test
What is a comparative DTH test?
Compare bovine reaction to both M. avium and M. bovis
If blebs are the same size = no infection
What species is most likely to infect cattle with Mycobacteria bovis?
Deer
Does pasteurization kill Mycobacteria bovis?
Unclear
Can cattle infected with Mycobacteria bovis be treated?
NO!
It’s illegal!
Only depopulation
What is Mycobacterium avium ssp. paratuberculosis (MAP)?
Johne’s disease
What is the prevalence of Johne’s or MAP in cattle?
8% in beef
22% in dairy herds
Can Johne’s/MAP affect other species?
Yes
Goats = no hyperproliferation
Humans = Crohn’s disease??
How long does it take for clinical signs to appear in animals with Johne’s/MAP?
1-3 years
What are the clinical signs of Johne’s/MAP?
- Emaciation but normal appetite
- Bottle jaw
- Lymph nodes
- Rough dry coat
What part of an infected animal is most infectious?
Feces!
Also milk, urine, semen
Is there a vaccine for Johne’s/MAP?
No!
What is the definitive test for Johne’s/MAP?
Fecal culture
BUT tests are NOT accurate until Stage III disease!
Is Johne’s/MAP reportable?
Yes!
Is there a vaccine for Johne’s/MAP?
No official vaccine
Can vaccinate with heat killed organisms
What are good biosecurity practices for Johne’s/MAP?
Removes calves shortly after birth
Use housing that can be disinfected
Purchase new animals that are > 3 yrs
What is Mycobacterium lepraemurium?
Leprosy-like disease in cats
