462
edits
Changes
no edit summary
<big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
<big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
<big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
<big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
===Overview===
*Causes contagious equine metritis
*Found in genital tracts of stallions, mares and foals
*Found in urethral fossa of stallions and clitoral fossa of mares
*Disrupts breeding programs on thouroughbred stud farms
===Characteristics===
*Short, non-motile Gram-negative rod
*Catalase, oxidase and phosphatase postitive
*Microaerophilic
*Grows slowly
*Fastidious growth - requires chocolate agar and 5-10% carbon dioxide for growth
*No growth on MacConkey
===Pathogenesis and pathogenicity===
*Transmission during coitus or via contaminated instruments
*Semenal fluid contaminated with ''T. equigenitalis'' from the urethral fossa
*Deposition in uterus required for infection to establish
*Bacteria replicate in uterus and cause acute endometritis
*Initial influx of mononuclear cells and plasma cells, followed by neutrophils, which cause a mucopurulent discharge
*Acute endometrial changes only last a few days
===Clinical infections===
*Contagious equine metritis
*Highly contagious venereal disease of thorougbred horses
*Infected stallions and mares are a reservoir of infection
*Stallions and some mares asymptomatic
*Mucopurulent vulval discharge and temporary infertility in mares after service with a carrier stallion
*Discharge may continue for 2 weeks, and mares may remain infertile for several weeks
*Mares may recover without treatment; 25% become carriers
*Re-infection can occur
*Foals become infected ''in utero'' or during parturition
*Infected foals and mares that recover clinically may be a source of infection
===Diagnosis===
*Specimens for bacteriology:
**Mares: swabs from clitoral fossa and sinuses and endometrium during oestrus
**Fillies: swabs from clitoral fossa
**Colts: penile sheath and tip of penis
**Stallions: swabs from urethra, urethral fossa, penile sheath and pre-ejaculatory fluid
*Place swabs in charcoal transport medium
*Isolation on chocolate agar with amphotericin B, crystal violet and streptomycin
*Small, smooth, yello-grey colonies
*Slide agglutination test
*Fluorescent antibody test
*Latex agglutination
*PCR
*Serology only detects active infection
===Treatment and control===
*Wash external genitalia of mares and stallions with 2% chlorhexidine combined with antimicrobials
*Lavage uterus with a penicillin-containing solution daily for 5-7 days in mares
*Ablation of clitoral sinuses in persistently-infected mares
*Notifiable disease
*Laboratory detection of carrier animals and clinical infections
*Hygiene
*Stop breeding if CEM diagnosed on stud farm
*Sample recovered animals to ensure free from disease
*Test-mating of stallions to 2 maiden mares to detect infection