Lesson 4a: Corynebacterium species Flashcards
- Gram-positive, pleomorphic bacteria
- Fastidious, requiring enriched media
Corynebacterium species
usual habitat of corynebacterium :
mucous membrane
Identification criteria of corynebacterium
o Morphology
o Colonial characteristics
o Biochemical react
most species of corynebacterium is oppotunistics except;
C. bovis
is a facultative intracellular pathogen capable of surviving and replicating in phagocytes whose virulence is linked to its cell wall lipid and to the production of an exotoxin, phospholipase D (PLD) that enhances its survival and multiplication in the host
C. pseudotuberculosis
Diptheria toxin from 2 species present in raw milk cows may implicate public health, what are the 2 species ?
C. ulcerans and C. pseudotuberculosis
in diagnosis Isolation and identification of bacteria from cell culture on blood agar, selective blood agar and MacConkey agar at how many degree & days ?
37°C for 1 to 2 days
Identification criteria for isolate
- Colonial characteristics
- Morphology in stained smears
- Presence or absence of haemolysis on blood agar
- Absence of growth on MacConkey agar
- Enhancement of haemolysis test for C. pseudotuberculosis
Molecular detection through
PCR
Caseous lymphadenits is caused by ______ in goats, sheep and cattle.
non-nitrate-reducing biotype of C. pseudotuberculosis
Manifestations of caseous lymphadenitis:
- chronic suppurative conditions
- encapsulated abscess formation “have an onion appearance”
- enlargement of lymph nodes
Corynebacterium pseudotuberculosis has been isolated from the _____ of affected goats thus posing a threat to public
milk
Sheep become infected by caseous lymphadenitis through ___________ by arthropod bites or from contaminated dips.
Contamination of shearing wound
Dx of caseous lymphadenitis:
- clinical lesions
- Gram-staining
- Bacterial culture from abscess swab samples, or detection antibodies by ELISA
Tx of caseous lymphadenitis
Tx: not effective,
Tx of control: strict border control, heightened
biosecurity, or culling
caused by the nitrate-reducing biotype of C. pseudotuberculosis in horses and cattle. Prevalent in countries with temperate weather
Ulcerative lymphadenitis
caused by C. renale group. The stress of parturition and the short urethra in the cow predispose to infection of the urinary tract.
Bovine pyelonephritis
Clinical signs of bovine pyelonephritis include:
- Fever
- anorexia
- decrease milk production
Dx of bovine pyelonephritis:
- Rectal palpation (unilateral thickened ureter/enlarged kidneys)
- bacterial culture from urine sample
- Presence of rbc or protein in urine
Tx of bovine pyelonephritis:
Penicillin
also called pizzle rot common in Merino sheep and Angora goats, is caused by C. renale and is characterized by ulceration around the preputial orifice (or vulva in ewes), with a brownish crust developing over the lesion
Ulcerative balanoposthitis
In non-nitrate reducing biotype of C. pseudotubercolusis the sheep & goats has this disease condition.
Caseous lymphadenitis
in C. pseudotubercolusis the nitrate-reducing biotype the horses & cattle has this disease.
Ulcerative lymphagitis, abscess
corynebacterium sp. occurs singly in?
palisades of parallel cells
in angular cluster, corynebacterium sp. it resembles?
Chinese characteristics in stained smears
C. pseudotubercolosis produces this 2 to enhances survival & multiplication.
- eoxotoxin
- phospholipase d
