Genetic and antigenic analysis of Chlamydia pecorum strains isolated from calves with diarrhea

J Vet Med Sci. 2015 Jul;77(7):777-82. doi: 10.1292/jvms.14-0585. Epub 2015 Feb 27.


Chlamydia pecorum (designated 22-58) was isolated in 2010 in HmLu-1 cells from the jejunum of a calf which died of necrotizing enterocolitis in Yamaguchi Prefecture, Japan. Immunohistochemical staining identified C. pecorum positive reactions in the jejunal villi. C. pecorum, designated 24-100, was isolated from the feces of a calf with diarrhea in another farm in Yamaguchi Prefecture in 2012. A significant increase in neutralizing antibody titers against C. pecorum was confirmed in paired sera. Nucleotide sequence identities of omp1 genes of the 2 isolates were 100%. The isolates were genetically and antigenically more closely related to C. pecorum Bo/Yokohama strain isolated from cattle with enteritis in Japan than to the other prototype strains, Bo/Maeda isolated from cattle with pneumonia and Ov/IPA isolated from sheep with polyarthritis. These results indicate that C. pecorum strains similar to 22-58 and 24-100 might be endemic in Yamaguchi Prefecture and cause enteric disease in cattle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Bacterial / genetics
  • Antigens, Bacterial / immunology
  • Cattle
  • Cattle Diseases / microbiology*
  • Chlamydia / genetics*
  • Chlamydia / immunology
  • Chlamydia Infections / immunology
  • Chlamydia Infections / microbiology
  • Chlamydia Infections / veterinary*
  • Diarrhea / microbiology
  • Diarrhea / veterinary*
  • Female
  • Intestines / microbiology
  • Polymerase Chain Reaction / veterinary


  • Antigens, Bacterial