Bovis ISSN 2398-2993

Chlamydia spp

Synonym(s): Chlamydophila

Contributor(s): Vetstream Ltd, Veronica Fowler , Tammy Hassel




  • Order: chlamydiales.
  • Family: chlamydiaceae.
  • Genus: chlamydia.


  • (Gk) khlamys-'cloak'.

Active Forms

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Clinical Effects



  • Obligate intracellular parasites characterized by a life cycle encompassing two morphological forms.
  • These forms comprise the elementary body (EB) and the reticulate body (RB).
    • EBs are small (0.2-0.6µm) and spherical.
    • RBs are larger (1.5µm) and amoeboid in shape.


  • Chlamdiae are shed within all secretions and excretions. Bacteria are also present within aborted fetuses and placentas.
  • Transmission via contaminated feces is particularly important.
  • Maybe transmitted in semen.
  • Interspecies transmission is not believed to be a significant occurrence.


Control via animal

  • High quality husbandry. 
  • Avoidance of stress in cattle.

Control via chemotherapies

  •  High doses of antibiotics (eg Tetracyclines Tetracyclines and Tylosin Tylosin. But antibiotics might not clear disease with animals later relapsing.

Control via environment

  • Strict quarantine.


  • Vaccines against C. abortus exist for sheep.
  • A range of vaccines are currently in development.


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Further Reading


Refereed Papers

  • Recent references from PubMed and VetMedResource.
  • Li J, Guo W, Kaltenboeck B, Sachse K, Yang Y, Lu G, Zhang J, Luan L, You J, Huang K, Qiu H, Wang Y, Li M, Yang Z & Wang C (2016) Chlamydia pecorum is the endemic intestinal species in cattle while C. gallinacea, C. psittaci and C. pneumoniae associate with sporadic systemic infection. Vet Microbiol 25 (193) PubMed.
  • Walker E, Lee E J, Timms P & Polkinghorne A (2015) Chlamydia pecorum infections in sheep and cattle: A common and under-recognised infectious disease with significant impact on animal health. Vet J 206 (3), 252-60 PubMed.
  • Poudel A, Elsasser T H, Rahman Kh S, Chowdhury E U & Kaltenboeck B (2012) Asymptomatic
    endemic Chlamydia pecorum infections reduce growth rates in calves by up to 48 percent.
    PLoS One 7 (9), PubMed.
  • Reinhold P, Sachse K & Kaltenboeck B (2011) Chlamydiaceae in cattle: commensals, trigger organisms, or pathogens? Vet J 189 (3), 257-67 PubMed.
  • Teankum K, Pospischil A, Janett F, Brugnera E, Hoelzle L E, Hoelzle K, Weilenmann R, Zimmermann D R, Gerber A, Polkinghorne A & Borel N (2007) Prevalence of chlamydiae in semen and genital tracts of bulls, rams and bucks. Theriogenology 67 (2), 303-10 PubMed.
  • Kaltenboeck B, Hehnen H R, & Vaglenov A (2005) Bovine Chlamydophila spp. infection: do
    we underestimate the impact on fertility?
    Vet Res Commun, 1-15 PubMed.