Bacto Flashcards
Actinomyces
Gram + Branching Filamentous Oral cavity commensal Club colonies - pussy granules Chronic osteomyelitis endogenous - dental rupture/oral abrasion Bone regrows porously, pus filled.
Actinomyces species?
A.bovis - chronic osteomyelitis in oral cavity
Rhodococcus
Gram + pleomorphic rods Saphrophyte, coprophilc strict aerobe Intracellular Live & replicate in alveolar macrophages VapA virulence
Rhodococcus species?
R. equi - Rattles
Staphylococcus
Gram + cocci clusters Facultative anaerobe Commensal Virulent coagulase + Catalase + NaCl, mannitol, sebaceous gland enzymes capsule Haemolytic MSCRAMMs
Staph species?
S.aureus - Bumblefoot/ Contagious mastitis
S. hyicus- Greasy Pig
Strep
Gram + cocci chains Facultative anaerobe Catalase - Capsule MSCRAMMs Ferment CHOs exotoxins Haemolytic
Strep species?
S. agalactiae - contagious mastitis S. dysagalactiae- enviro mastitis S. uberis- enviro mastitis S. equi zooepidemicus- transport pneumonia/ mare endometritis S. equi equi- Strangles
Corynebacterium
Gram + rod "clubs" Utilise urease Exogenous Arthropod vectors Obligate parasite Abcessation LUCOTOXIC SURFACE LIPIDS resits phagocytosis.
Corynebacterium species?
C. pseudotuberculosis - Cheesy gland/ Pigeon Breast
C. renale - Pizzle rot/ pylonephritis
Mycobacterium
Gram + rod Strict aerobe Saprophyte Obligate parasite Intracellular Chronic granulomatous lesions Live & replicate in macrophages
Mycobacterium species?
M. bovis - bovine tuberculosis
M. avium subsp. paratuberculosis - Johne’s disease
M. avium - avian tuberculosis & lymphadenitis in pigs
Nocardia
Gram + rods Saprophytes not too pathogenic, very opportunistic Intracellular Cell wall lipids Chronic Inflammation Local comprimise
Nocardia species?
N. asteroides - Nocardiosis, Mastitis & chronic inflammation inc. granular & pus
Dermatophilus
Gram + rod Branching, filamentous, motile Obligate parasite Host compromise Strict aerobe Keratinases, proteolytic, haemolytic Tries to migrate to deeper epidermis Motile zoospores NEED moisture targets living/ uncornified
Dermatophilus species?
Dermatophilus congolensis- Greasy heel, rain scald, Strawberry footrot
Truperella
Gram + rod Strict anaerobe Pyolysin exotoxin lyses RBC Dermonecrotising Purulent inflammation
Trueperella species?
T. pyogenes- summer, purulent mastitis & conditions associated with forms of purulent inflammation e.g. footrot
Actinobacillus
Gram + Rod Urease strict anaerobe Requires alkaline conditions Commensal boars prepuce >10weeks age Venereal transmission Sows in oestrous
Actinobacillus species?
A.suis - Exogenous transmission through mating. Needs alkaline conditions so only proliferates when Sow is in oestrous- oestrogen levels raise urine pH. UTI
Listeria
Gram + rod Intracellular Psychotrophic Facultative anaerobe Commensal, saprophyte Exogenous/ Endogenous Visceral/ Neural
Listeria species?
L. monocytogenes-
Visceral = oral ingestion, enteritis/ microabscessation/ septicaemia/ other organs
Neural= Buccal injury/ damage peripheral triageminal nerves/ damage CNS ‘Circling Disease’
** Carrier status
Erysiopelothrix
Gram + rod Neurominidase Facultative anaerobe Survives in environment, resistant Commensal tonsils Capsule Septicaemia Carriers (immune status) Quarantine
Erysiopelothrix species?
E. rhusiopathiae - Acute septicaemia= death
Chronic septicaemia –> joints = arthritis heart = vegetative endocarditis skin= haemorrhage diamonds
Lyses cells in gastrointestinal tract for enteritis
Bacillus
Gram + rod
Facultative anaerobe
Saprophyte
Endospore
exotoxins released
3 x toxic factors
Oedema Factor (EF) – efflux from cells
Protective antigen (PA) – req for other two
EF + PA = Lethal Factor (LF) – macrophages release IL-1 & TNF … inflammatory cascade + 2ndary cascade
Overpowering of the reticuloendothelial system
causes cardio shock & damage to endothelial cells.
Bacillus species?
B. anthracis- Ingestions/ inhalation/ wound contaminaiton. PA + EF = LF.
Macrophages release IL-1, TNF, cleared by reticoendothelial system but when exceeds splenic capacity causes hypovalemic shock & damage to endothelial cells so bleed from orifices & black lumpy spleen. No rigour mortis.
Clostridium
Gram + Rod
exotoxins
Endospore
Important to compare & contrast
Clostridium T species
C. Tetani- Gram + rod, capsule, exotoxin, fac anaerobe, spores in 02, ubiquitous in environ. Wound contamination- haemolytic toxin that cleaves proteins required on the synaptic membrane for inhibitory actions of GABA & glycine neurotransmitters. Rigid paralysis
Clostridium B species
C. Botulinum- Gram + rod, non-capsule, motile, exotoxin (7) , strict anaerobe, uneven in environment, ingestion. Pathogenesis through intoxication. Spore in low O2 tension, 12-35, organic matter. Toxin cleaved to become active prototoxin. Travels in blood to neuromuscular junction to block action of acetylcholine. Muscles cannot flex. Resp paralysis by flaccid paralysis.
Enterobacteriaceae
Oxidase - Facultative anaerobes Motile Produce urease Saprophyte & Gut commensal MaConkeys AGAR --> coliforms = Escheria/ Enterobacter/Klebsiella ... Non-lactose fermenters = Salmonella/ Yersinia/ Proteus
Pathogenesis of Salmonella?
ingestion»_space; dose critical»_space; adhesion to mucosal cells by F antigen»_space; entry into enterocytes (don’t lyse)»_space; release into lamina propria (sloughing & inflammation)»_space; malabsorption»_space; Resist phagocytosis & complement (K antigen)»_space; exacerbated by antimicrobials»_space; diarrhoea/ dysentery»_space; septicaemia»_space; carrier status?
Types of Escheria Coli?
ETEC - toxigenic EHEC - haemorrhagic EPEC - pathgenic DAEC - Diffusely adhering EAEC - Aggregative EIEC - Invasive
ETEC?
Diarrhoea without damaging intestinal cell wall & WITHOUT inflammation.
Watery diarrhoea
EPEC?
Virulence plasmid causes destruction of microvilli, for malabsorption. No enterotoxins produced. Mild inflammation due to cellular shedding.
EHEC?
Attach & colonise mucosa by fimbria & intimin
Exotoxins that are enterotoxin & cytotoxic. Haemorraghic diarrhoea. Carriers
EIEC?
Adhere & invade colonic cells, cell death & chronic ulceration. Inflammation + diarrhoea = dysentary.
Pasteurellaceae?
Gram - Oxidase + Coccobacilli Oxidase + Facultative anaerobes = Actinobacillus/ Haemophilus/ Avibacterium/ Manheimia/ Pasteurella commensals
