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− | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
| + | #REDIRECT[[:Category:Campylobacter species]] |
− | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
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− | * Linked to:
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− | ** [[Intestines - Catarrhal Enteritis#Undifferentiated Neonatal Calf Diarrhoea|Undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves.
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− | ** Food poisoning ([[Intestines - disease due to pathogens#Campylobacter jejuni|Campylobacter jejuni]]).
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− | ===Overview===
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− | *Live on mucosa of intestinal and genital tract and can be commensals or pathogens
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− | *Enteric species cause disease in humans
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− | *Other species cause infertility and abortion in cattle and sheep
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− | *Excreted in faeces of birds, (''C. jejuni'' and ''C. lari'') as well as pigs contaminating water and food supplies
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− | *''C. fetus'' restricted to bovine prepucial mucosa
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− | ===Characteristics===
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− | *Curved, Gram negative rods
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− | *Polar flagellum aids motility
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− | *Daughter cells remain joined giving gull-wing or spiral appearance
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− | *Microaerophilic
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− | *Sensitive to drying
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− | *Thermophilic species - ''C. jejuni, C. coli''
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− | *Non-thermophilic species e.g. ''C. fetus''
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− | *Grow on enriched media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension
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− | *''C. jejuni'' requires increased temperatures for growth
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− | *Many grow on MacConkey
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− | *Oxidase positive, non-fermentative
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− | *''C. fetus'' subspecies ''venerealis'' and subspecies ''fetus'' have small, round, smooth, translucent colonies
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− | *''C. jejuni'' has small, flat, grey colonies with watery appearance
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− | ===Pathogenesis and pathogenicity===
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− | *''C. fetus'' subspecies ''fetus'' and subspecies ''venerealis'' possess a microcapsule (S layer) which resists phagocytosis and serum-mediated destruction and enhances survival in the genital tract
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− | *Antigens of S layer undergoes antigenic shifts in ''C. fetus'' subspecies ''venerealis'', allowing persistence in the host
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− | *''C. jejuni'' attaches and invades host enterocytes and produces enterotoxin-like substances
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− | ===Clinical infections===
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− | *''Campylobacter fetus'' subspecies ''venerealis''
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− | **Venereal infection of cattle
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− | **Infertility in female cattle
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− | **Found in glandular crypts of prepuce of bull with no clinical signs - carriers
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− | **Causes catarrhal inflammation in female genital tract
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− | **Endometritis prevents implantation until infection gone and causes early embryonic death, occasionally sporadic abortion
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− | **May remain infertile for 3-5 months before immunity develops, which lasts 4-5 years
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− | **Effective immunity includes induction of IgA in the vagina and IgG in the uterus
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− | **Bacteria may persist in the vagina and be transmitted to bulls
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− | ===Diagnosis===
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− | *Smears stained with dilute carbol fuschin for 4 minutes
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− | ===Control===
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− | ===Treatment===
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