Gram + Rods Actinomyces, actinobaculum and trueperella, dermatophilus

Question 1

whats important about the genus’ actinomyces, treperella, and actinobaculum?

Answer 1

no Mycolic acid

Question 2

what are antibiotics from acinomycets?

Answer 2

amphotericin
chloramphenicol
tetracycline
erythromycin
neomycin
streptomycin
gentamycin

Question 3

Cell morphology of actinomycetes look like?

Answer 3

fungal spores

Question 4

actinomyces, actinobaculum and trueperella frequently are associated with?

Answer 4

pyogenic infections in livestock

Question 5

Actinomyces spp. characteristics

Answer 5

virulence factors not well described
pathogenic species- mucosa of oropharynx (some host species restrictions)
facultative anaerobic, anaerobic, capnophilic
most catalase negative
colonies- molar like

Question 6

what are the common species of actinomyces?

Answer 6

viscosus
naeslundii
israelii
hordeovulneris

Question 7

Dz of actinomyces?

Answer 7

chronic, progressive pyogranulomatous Dz
polymicrobial infection
initiated by disruption of mucosal barrier ( GRASS AWNS)
Spread by direct extension
Chronic infections may cause bone lysis
common in active outdoor animals (hunting breeds)

Question 8

Actinomyces bovis?

Answer 8

Lumpy Jaw

pyogranulomatous osteomyelitis

Question 9

Dx actinomyces?

Answer 9

Must request aerobic and anaerobic culture

Cultue/ microscopic examination of granules

Question 10

Tx actinomyces?

Answer 10

Pen G, Iodides
may require long term Tx 3-12m w/ high dose Penicillin
Surgical excision of foreign bodies

Question 11

Control of actinomyces?

Answer 11

minimize risk of mechanical injury, remove foreign bodies

Question 12

Dermatophilus congolensis characteristics?

Answer 12

Filamentous branching
Tram track= coccoid fragments become motile zoospores
zoospores- chemotaxis for CO2
Aerobic
catalase positive
Can affect: cattle, sheep, goats, horses, and les frequently pigs, dogs, and cats

Question 13

D. congolensis Dz?

Answer 13

epidermal abscesses w/ hyperkeratosis

Question 14

Virulence properties of D. congolensis?

Answer 14

chemotaxis of zoospore
keratinolytic activity
survival of zoospores in dry scab-like crusts

Question 15

Whats a good way to Dx D. congolensis?

Answer 15

Methylene blue- tram track appearance

Question 16

Disease common names of D. congolensis?

Answer 16

Rain scald
strawberry footrot
dermatophilosis

Very prevalent in St. Kitts cattle

Question 17

Tx of D. congolensis?

Answer 17

Pen G and Tetracycline

Question 18

Control of D. congolensis?

Answer 18

treat and isolate infected individuals

tick control and brush removal

Question 19

Food animal pathogen and go?

Answer 19

Trueperlla pyogenes

Question 20

Trueperlla pyogenes

Answer 20

pleomorphic
facultative anaerobe
no spores
no motility
no capsule
capnophilic
suppurative infections in cows and swine
sporadic Dz

FOUND ON MUCOUS MEMBRANES *
MOST INFECTIONS ARE PROBABLY ENDOGENOUS*

Question 21

trueperella pyogenes causes what in cattle?

Answer 21

summer mastitis, can also cause abortion

Question 22

Dx of Trueperella pyogenes?

Answer 22

necropsy

Question 23

Actinobaculum Suis, Oxygen requirements?

Answer 23

ANAEROBIC

Question 24

Where is A. suis commensal at?

Answer 24

perpucial mucosa of boars

SEXUALLY TRANSMITTED!!

Question 25

what does A. suis cause?

Answer 25

cystitis and pyelonephritis 3-4 wks post-coitus
Death= renal failue
similar to bovine pyelonephritis

Question 26

what is the virulence factor of A. suis?

Answer 26

UREASE Urea- amonia

Question 27

caseous lymphadenitis in sheep?

Answer 27

Corynebacterium psuedotuberculosis, Contagious

Question 28

is rhodococcus equi an obligate intracellular bacteria?

Answer 28

no facultative intracellular

Question 29

what is MIC?

Answer 29

the lowest concentration of antimicrobial agent which can inhibit growth of bacteria

Question 30

toxin and capsule are required for virulence of anthrax?

Answer 30

true!!