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Replaced content with "Category:Delete Relisted and rewritten by Steph under Infectious Bovine Keratoconjunctivitis as most information was disease related."
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−Causes : New Forest Eye Disease+===Overview===+
−*''Moraxella bovis'' causes infectious bovine keratoconjunctivitis
−*Found on mucous membranes of carrier cattle
−*Susceptible to desiccation therefore short survival in environment
−*Flies act as vectors, in which the bacteria can survive 72 hours
−*Other species non-pathogenic
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−===Characteristics===
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−*Short, plump Gram negative rods or cocci occuring in pairs
−*Non-motile
−*Aerobic
−*Catalase positive, oxidase postitive
−*Unable to utilise sugars
−*No growth on MacConkey agar
−*Growth enhanced by addition of blood or serum to media
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−===Pathogenesis and pathogenicity===
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−*Virulent strains have fimbriae, are haemolytic and grow into agar
−*Fimbriae allow adherence to the cornea
−*Q fimbriae are specific for colonisation; I fimbriae allow local persistence of infection
−*Fimbrial antigens stimulate immunity
−*Haemolysin, fibrinolysin, phosphatase, hyaluronidase and aminopeptidase as well as LPS contribute to virulence
−*Haemolysin damages neutrophil membranes; release of hydrolytic enzymes from these [[Neutrophils|neutrophils]] damages the corneal surface
−*Isolates from carrier animals often avirulent, and are non-haemolytic and have no fimbriae; reversion to virulence can occur
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−===Clnical infections===
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−*Infectious bovine keratoconjunctivitis, or pink-eye/New Forest disease is an ocular disease of cattle
−*Highly contagious infection of superficial tissues of eye
−*Affects animals under 2 years old
−*Decreased weight gain in beef cattle, decreased milk production in dairy herds
−*Age-related immunity due to previous exposure
−*Antibodies against haemolysin neutralise different strains, whereas antibodies to fimbriae are strain-specific
−*Asymptomatic carrier animals harbour the bacteria in the nasolacrimal ducts, nasopharynx and vagina
−*Transmission by direct contact, aerosol and via flies
−*Clinical signs: blepharospasm, conjunctivitis, lacrimation
−*Keratitis and corneal ulceration, opacity and abscessation may lead to panophthalmitis and permanent blindness
−*Stromal oedema; coning of cornea
−*Cornea may heal or undergo permanent scarring
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−===Diagnosis===
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−*Swabs of lacrimal secretions
−*Fluorescent antibody test demonstrate presence of ''M. bovis''
−*Culture on blood agar; colonies are round, small, shiny and friable
−*Virulent strains surrounded by complete haemolysis and are embedded in the agar
−*No growth on MacConkey
−*Autoagglutination in saline
−*Short Gram negative rods on smears
−*7 serotypes based on fimbriae
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−===Treatment and control===
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−*Subconjunctival or topical antimicrobials
−*Isolate animals
−*Reduce mechanical irritation such as dust, grass, grass seeds
−*Insect control
−*Control concurrent infections
−*Prophylactic oxytetracycline for animals at risk
−*Vitamin A supplementation
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−[[Category:Bacteria miscellaneous]][[Category:Rods]][[Category:Cocci]][[Category:Cattle Bacteria]]
−[[Category:Neurological Diseases - Cattle]]
−[[Category:To Do - Steph]]
[[Category:Delete]]
−Relisted and rewritten by Steph under [[Infectious Bovine Keratoconjunctivitis]] as most information was disease related.
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