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− | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
| + | #REDIRECT[[:Category:Bacillus species]] |
− | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
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− | [[Bacillus anthracis]] | |
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− | *''CAR bacillus'' in [[Bacterial infections#CAR bacillus|URT infection in cattle]] and [[Bacterial infections#In Rabbits|URT infection in rabbits]]
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− | * Can cause vascular fragility, leading to [[General Pathology - Haemostasis#Haemorrhagic Disease Due To Vascular Fragility|haemorrhagic disease]].
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− | ===Overview===
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− | *Mostly non-pathogenic environmental organisms
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− | *''Bacillus anthracis'' causes anthrax
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− | *''Bacillus licheniformis'' may cause shoradic abortions in cattle and sheep
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− | *''Bacillus cereus'' causes food poisoning in humans and mastitis in cows
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− | ===Characteristics===
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− | *Large, Gram positive rods
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− | *Produce endospores
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− | *Aerobes or facultative anaerobes
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− | *Grow on non-enriched media
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− | *Motile
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− | *Catalase positive, oxidase negative
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− | *''Bacillus anthracis'' colonies are up to 5mm diameter, flat, dry, grey, with a ground-glass appearance; curled outgrowthsfrom the edge of the colony give a 'medusa head' appearance; non-haemolytic (differentiate from ''Bacillus cereus'')
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− | *''Bacillus licheniformis'' forms dull, rough, wrinkled colonies, with hair-like outgrowths
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− | *Biochemical tests for identification
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− | *Can often tolerate adverse environmental conditions
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− | ===''Bacillus anthracis''===
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− | *Saprophyte in soil
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− | *Capsule composed of homopolymer of D-isomer of glutamic acid allows survival in the body by resisting phagocytosis
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− | *Capsule stains mauve with polychrome methylene blue in the MacFadyean's reaction - identify anthrax in blood samples
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− | *Bacilli appear as chains of dark blue, square-ended rods surounded with the capsule
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− | *Extracellular toxin (holotoxin) composed of oedema factor, protective factor and lethal factor
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− | *
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− | ===''Bacillus licheniformis''===
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− | *Widespread in the environment
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− | *Associated with food spoilage
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− | *Abortion in cattle and sheep, possibly from spoiled silage or hay
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