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*Usually asymptomatic infections in chickens and turkeys, but occasional outbreaks of avian hepatitis occur with decreased egg production, loss of condition, haemorrhage and necrosis of liver; phase contrast microscopy demonstrates curved rods in bile; in-feed dihydrostreptomycin sulphate in outbreak
*Usually asymptomatic infections in chickens and turkeys, but occasional outbreaks of avian hepatitis occur with decreased egg production, loss of condition, haemorrhage and necrosis of liver; phase contrast microscopy demonstrates curved rods in bile; in-feed dihydrostreptomycin sulphate in outbreak
*Implicated in [[Intestines Catarrhal Enteritis - Pathology#Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves[[Category:Campylobacter_species]][[Category:Dog]][[Category:Cattle]][[Category:Sheep]]
*Implicated in [[Intestines Catarrhal Enteritis - Pathology#Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves[[Category:Campylobacter_species]][[Category:Dog]][[Category:Cattle]][[Category:Sheep]]
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* An important enteropathogen of man and a number of animal species.
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* The largest cause of food-poisoning in the UK.
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** Is therefore a public health issue.
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* Very widely distributed on the farm- carried in the intestinal tract of:
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** Cattle
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** Sheep
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** Dogs
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** Chickens
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** Wild birds
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* Widespread distribution on the farm means that it is hyperendemic.
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** All animals are regularly exposed to it by the faecal oral route.
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** Passive (colostral) protection is helpful while active immunity develops.
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* There is no regular exposure in the hygienic environment of the human or pet dog.
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** These animals are much more susceptible to infection.
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* The intestinal contents of the broiler chicken may be spread around the abdominal cavity at slaughter.
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** Most poultry is moderately or heavily contaminated.
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*** If frozen chicken is inadequately thawed, bacteria may remain viable in the abdominal cavity.
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*** Bacteria may be ingested by humans handling the raw meat.
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====Pathogenesis====
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* Bacteria colonise the gut, attach to and invade the mucosa, and produce toxin.
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* Causes colitis, characterised by:
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** Necrosis of absorptive epithelial cells
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** Erosion of the mucosa
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** Crypt abscesses
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** Infiltration of inflammatory cells into the mucosa.
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*** Primarily [[Neutrophils - WikiBlood|neutrophils]].
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* Functional flagella are important as virulence factors.
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** Non-flagellate campylobacter do not colonise in vivo, and are less invasive in vitro.
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* Diagnosed by laboratory diagnosis.