Lesson 3: Genus Actinobacteria, Nocardia and Dermatophilus Flashcards
General Description
- gram-positive bacteria
- slow growth on lab media
- opportunistic pathogen
- actinomyces, arcanobacterium, actinobaculum
- nocardia species
- dermatophilus congolensis
- crosiella equi
actinomyces, arcanobacterium, and actinobaculum species
- anaerobic or facultative anaerobic
- morphologically heterogeneous
- non-spore forming, non-motile
- ziehl-neelsen-negative
- colonize mucous membranes
- required enriched growth media for growth
Actinomyces pyogenes- Corynebacterium pyogenes- Arcanobacterium pyogenes- Trueperella pyogenes
nocardia species
- aerobic, non-motile
- gram-positive
- spores from aerial filaments
- growth on Sabouraud dextrose sugar
- ziehl-Neelsen-positive
- soil saprophytes
- long, slender, rods and cocci in smears
Dermatophilus congolensis
- gram-positive, filamentous, branching
- aerobic and capnophilic
- motile coccal zoospores 1.5 um
- no growth on sabouraud dextrose sugar
- found in scabs and in foci on skin of carrier animals
associated with equine nocardiform placentitis, leading to loss of the foal in approximately 50% of cases
crosiella equi
Class: Actinobacteria
Order: Actinomycetalis
Sub-order: Actinomycinaeae
Family: Actinomycetaeae
Genus: Actinomyces
Species; A. bovis, A. viscosus, A. hordeovulneris
Genus: Actinobaculum
Species: A. suis
Genus: Arcanobacterium
species; A. pyogenes
Suborder: Corynebacterinaeae
Family: Corynebacteriaceae
Genus: Mycobacterium
Species; M. bovis, M. avium, M. paratubercolusis
Genus: Corynebacterium
Species; C. pseudotubercolusis, C. pilosum, C. renali
Genus: Rhodococcus
Specie; R. equi
Genus: Nocardia
Species; N. asteroides, N. farcinica
Suborder: Micrococcinaeae
Family: Dermatophilaceae
Genus: Dermatophilus
Specie; D. congolensis
Suborder: Pseudocardinaeae
Family: Pseudocarcidiaceaea
Genus: Crosiella
specie; C. equi
Produces pyolisin and adhesins
Trueperella pyogenes
an opportunistic pathogen and is a common cause of suppurative lesions in many domestic species worldwide, especially cattle, pigs and sheep
infection with Trueperella pyogenes
caused by Actinomyces viscosus which result to subcutaneous pyogranulomatous lesion and extensive fibrovascular proliferation on the peritoneal or pleural surfaces with sanguinopurulent exudate in the affected cavity.
Canine actinomycosis
caused by Actinomyces bovis which result to chronic rarefying osteomyelitis following trauma to the mucosa from rough feed or through dental alveoli during tooth eruption
Bovine actinomycosis (lumpy jaw)
This specific disease, which affects the urinary tract of pregnant sows, is transmitted at coitus and is potentially fatal.
Porcine cystitis and pyelonephritis
are usually confined to the epidermis. Dx: clinical signs and lesions. Tx: Penicillin-Streptomycin
Infections with D. congolensis
similar to actinomycosis. Tx: Amikacin, imipenem-cilastatin and cotrimoxazole
Nocardia sp. infections
contain both acidic as result it has affinity for both acidic and basic components of the cell
Giemsa staining
Specimens suitable for laboratory examination include scab material and sample of skin fixed in formalin
Dermatophilosis
