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Created page with '===Overview=== *Live on mucosa of intestinal and genital tract and can be commensals or pathogens *Enteric species cause disease in humans *Other species cause infertility and a…'
===Overview===
*Live on mucosa of intestinal and genital tract and can be commensals or pathogens
*Enteric species cause disease in humans
*Other species cause infertility and abortion in cattle and sheep
*Excreted in faeces of birds, (''C. jejuni'' and ''C. lari'') as well as pigs contaminating water and food supplies
*''C. fetus'' restricted to bovine prepucial mucosa
===Characteristics===
*Curved, Gram negative rods
*Polar flagellum aids motility
*Daughter cells remain joined giving gull-wing or spiral appearance
*Microaerophilic
*Sensitive to drying
*Thermophilic species - ''C. jejuni, C. coli''
*Non-thermophilic species e.g. ''C. fetus''
*Grow on enriched selective media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension
*''C. jejuni'' requires increased temperatures for growth
*Many grow on MacConkey
*Oxidase positive, non-fermentative
*''C. fetus'' subspecies ''venerealis'' and subspecies ''fetus'' have small, round, smooth, translucent colonies
*''C. jejuni'' has small, flat, grey colonies with watery appearance
*Smears stained with dilute carbol fuschin for 4 minutes
===Pathogenesis and pathogenicity===
*''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
*Antigens of S layer undergoes antigenic shifts in ''C. fetus'' subspecies ''venerealis'', allowing persistence in the host
*''C. jejuni'' attaches and invades host enterocytes and produces enterotoxin-like substances
*Flagellae of ''C. jejuni'' required for colonisation
[[Campylobacter fetus subspecies venerealis]]
===''Campylobacter fetus'' subspecies ''fetus''===
*Sporadic abortion in cows and sheep
*10% of ovine abortions in the UK
*Enteric organism of sheep, goats and cattle; faecal-oral transmission
*Ingestion during last trimester of pregnancy causes a bacteraemia
*Bacteria reach the uterus
*Necrotic placentitis causes late abortion, still birth or weak lambs
*Sporadic abortion in cattle
*Aborted lambs may have round necrotic lesions on surface of liver
*Aborting ewes source of infection for vulnerable animals
*Up to 20% of flock may abort
*Solid immunity developed
*S layer immunodominant antigen
*Diagnosis: hepatic lesions in lambs; presence of organisms in foetal abomasum; isolation and identification
*Treatment/control: isolate aborting ewes; destroy placenta; move other ewes to clean pasture; vaccinate flock with bacterin during outbreak and prophylactically; chlortetracycline in feed in an outbreak
===[[Intestine Pathogens - Pathology#Campylobacter jejuni|''Campylobacter jejuni'']]===
*Widespread on farms - hyperendemic
*Carried as commensals in intestines of cattle, sheep, dogs, wild birds and especially chickens
*Farm animals regularly exposed via faecal-oral route; maternal antibody protects while active immunity develops
*Animals with little exposure are very susceptible, e.g. humans, pets
*Most chicken carcasses contaminated, leading to food poisoning and enterocolitis in people from uncooked meat
*Colonisation, attachment and invasion of colonic enterocytes; toxin production
*Necrosis of colonic absorptive epithelial cells, erosion of mucosa, crypt abscesses, inflammatory infiltrate of [[Neutrophils - WikiBlood|neutrophils]] into mucosa causes colitis
*Enteritis and diarrhoea in susceptible dogs; treatment with enrofloxacin
*Causes abortion in ewes
*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:Bacteria]][[Category:Gram_negative_bacteria]]
*Live on mucosa of intestinal and genital tract and can be commensals or pathogens
*Enteric species cause disease in humans
*Other species cause infertility and abortion in cattle and sheep
*Excreted in faeces of birds, (''C. jejuni'' and ''C. lari'') as well as pigs contaminating water and food supplies
*''C. fetus'' restricted to bovine prepucial mucosa
===Characteristics===
*Curved, Gram negative rods
*Polar flagellum aids motility
*Daughter cells remain joined giving gull-wing or spiral appearance
*Microaerophilic
*Sensitive to drying
*Thermophilic species - ''C. jejuni, C. coli''
*Non-thermophilic species e.g. ''C. fetus''
*Grow on enriched selective media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension
*''C. jejuni'' requires increased temperatures for growth
*Many grow on MacConkey
*Oxidase positive, non-fermentative
*''C. fetus'' subspecies ''venerealis'' and subspecies ''fetus'' have small, round, smooth, translucent colonies
*''C. jejuni'' has small, flat, grey colonies with watery appearance
*Smears stained with dilute carbol fuschin for 4 minutes
===Pathogenesis and pathogenicity===
*''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
*Antigens of S layer undergoes antigenic shifts in ''C. fetus'' subspecies ''venerealis'', allowing persistence in the host
*''C. jejuni'' attaches and invades host enterocytes and produces enterotoxin-like substances
*Flagellae of ''C. jejuni'' required for colonisation
[[Campylobacter fetus subspecies venerealis]]
===''Campylobacter fetus'' subspecies ''fetus''===
*Sporadic abortion in cows and sheep
*10% of ovine abortions in the UK
*Enteric organism of sheep, goats and cattle; faecal-oral transmission
*Ingestion during last trimester of pregnancy causes a bacteraemia
*Bacteria reach the uterus
*Necrotic placentitis causes late abortion, still birth or weak lambs
*Sporadic abortion in cattle
*Aborted lambs may have round necrotic lesions on surface of liver
*Aborting ewes source of infection for vulnerable animals
*Up to 20% of flock may abort
*Solid immunity developed
*S layer immunodominant antigen
*Diagnosis: hepatic lesions in lambs; presence of organisms in foetal abomasum; isolation and identification
*Treatment/control: isolate aborting ewes; destroy placenta; move other ewes to clean pasture; vaccinate flock with bacterin during outbreak and prophylactically; chlortetracycline in feed in an outbreak
===[[Intestine Pathogens - Pathology#Campylobacter jejuni|''Campylobacter jejuni'']]===
*Widespread on farms - hyperendemic
*Carried as commensals in intestines of cattle, sheep, dogs, wild birds and especially chickens
*Farm animals regularly exposed via faecal-oral route; maternal antibody protects while active immunity develops
*Animals with little exposure are very susceptible, e.g. humans, pets
*Most chicken carcasses contaminated, leading to food poisoning and enterocolitis in people from uncooked meat
*Colonisation, attachment and invasion of colonic enterocytes; toxin production
*Necrosis of colonic absorptive epithelial cells, erosion of mucosa, crypt abscesses, inflammatory infiltrate of [[Neutrophils - WikiBlood|neutrophils]] into mucosa causes colitis
*Enteritis and diarrhoea in susceptible dogs; treatment with enrofloxacin
*Causes abortion in ewes
*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:Bacteria]][[Category:Gram_negative_bacteria]]