Bacillus Flashcards
shape and arrangement
rods
pairs or long chains
endospore survival
more than 50 years
gram, size, spore, respiration, growth, motility, catalase, oxidase, pathogenic
-gram positive
-large
-endospores produced
-aerobes or facultative anaerobe
-growth on non enriched media
-most motile
-most catalase positive
-most oxidase negative
-majority non pathogenic environmental organisms
B anthracis motility, hemolysis, lactithinase, gamma phage
-non motile
-non hemolytic on sheep blood agar
-weak and slow on lecthinase activity egg yolk agar
-effect of gamma phage – lysis
colonie appearance of B anthracis
-5mm diameter
-flat
-dry
-greyish
B cereus motility, hemolysis, lecithinase, pathogenicity, gamma phage, colonies
-motile
-hemolytic on sheep blood agar
-strong and rapid lecithinase activity on egg yolk agar
- pathogenicity – no effect
effect of gamma phage – lysis rare
-greenish tinge to colonies
B licheniform colonies
dull, wrinkled, strongly adherent to agar
clinical manifestation of B anthracis
-fatal peracute or acute septicemic anthrax
-subacute anthrax with edematous swelling in pharyngeal region
-septicemia with colic and enteritis
-skin, pulmonary, intestinal forms
clinical manifestation of B cereus
-mastitis (rare)
-food poisoning, eye infections
clinical manifestations of B licheniformis
-sporadic abortions in cow and sheep
pathogenesis
-capsule provides resistance to phagocytosis
-protective antigens , oedema factor, lethal factor
-oedema factor targets neutrophils
-lethal factor targets macrophages, dendritic cells, neutrophils
which species more susceptible
sheep and cattle
clincial signs
-fever
-depression
-congested mucosae and pectechiae
-abortions
what to do when animals die
-do NOT do necropsy
-report to government they will take care of it
lesions
-rapid bloating
-incomplete rigor mortis
-ecchymotic hemorrhage and oedema
-dark unclotted blood and blood stained fluids in cavities
-large and soft spleen
main characteristic lesion in cattle
large and soft spleen
diagnosis
-unclotted blood in mouth, nose, anus
-blood sample or fluids – gram staining
-bacterial culture
-PCR
-ascoli test, precipitation, gel diffusion
what do you see with ascoli test
immuno test
specific antibodies against bacteria
will see agglutination
not very specific
treatmetn
penicillin
oxytetracycline
control in endemic regions
-annual vaccination
-live vaccine
-sterne strain
-spores converted to avirulent on encapsulated vegetative organsims
control in non endemic regions
-avoid movement of animals
-PPE and foot baths
-immediate disposal of carcasses
-fumigate with formaldehyde
