Difference between revisions of "Campylobacter species"
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| − | === | + | ===''Campylobacter fetus'' subspecies ''venerealis''=== |
| − | + | *Venereal infection of cattle | |
| − | + | *Infertility in female cattle | |
| − | + | *Found in glandular crypts of prepuce of bull with no clinical signs - carriers | |
| − | + | *Causes catarrhal inflammation in female genital tract | |
| − | + | *Endometritis prevents implantation until infection gone and causes early embryonic death, occasionally sporadic abortion | |
| − | + | *May remain infertile for 3-5 months before immunity develops, which lasts 4-5 years | |
| − | + | *Effective immunity includes induction of IgA in the vagina and IgG in the uterus | |
| − | + | *Bacteria may persist in the vagina and be transmitted to bulls | |
| − | + | *Diagnosis: | |
| + | **Fluorescent antibody test on genital discharges from bull/cow | ||
| + | **Vaginal mucus agglutination test | ||
| + | **ELISA to IgA antibodies in vaginal mucus after an abortion | ||
| + | **PCR for detection in semen | ||
| + | *Treatment: dihydrostreptomycin intrauterine for cows and systemically or topically for bulls | ||
| + | *Vaccination: bacterin in oil adjuvant | ||
| + | |||
| + | |||
| + | ===''Campylobacter fetus'' subspecies ''fetus;;=== | ||
| + | |||
| + | * | ||
Revision as of 07:53, 18 May 2008
- Linked to:
- Undifferentiated neonatal calf diarrhoea, a mixed viral enteritis in calves.
- Food poisoning (Campylobacter jejuni).
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 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
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
Campylobacter fetus subspecies venerealis
- Venereal infection of cattle
- Infertility in female cattle
- Found in glandular crypts of prepuce of bull with no clinical signs - carriers
- Causes catarrhal inflammation in female genital tract
- Endometritis prevents implantation until infection gone and causes early embryonic death, occasionally sporadic abortion
- May remain infertile for 3-5 months before immunity develops, which lasts 4-5 years
- Effective immunity includes induction of IgA in the vagina and IgG in the uterus
- Bacteria may persist in the vagina and be transmitted to bulls
- Diagnosis:
- Fluorescent antibody test on genital discharges from bull/cow
- Vaginal mucus agglutination test
- ELISA to IgA antibodies in vaginal mucus after an abortion
- PCR for detection in semen
- Treatment: dihydrostreptomycin intrauterine for cows and systemically or topically for bulls
- Vaccination: bacterin in oil adjuvant
Campylobacter fetus subspecies fetus;;
Diagnosis
- Smears stained with dilute carbol fuschin for 4 minutes