title: Longitudinal prevalence and faecal shedding of Chlamydia pecorum in sheep.
abstract: The prevalence and faecal shedding of Chlamydia spp. in sheep in Australia has not been well described. Two species-specific quantitative PCRs (qPCRs) targeting the chlamydial outer membrane protein cell surface antigen gene (ompA) were validated and used to determine the prevalence and faecal shedding of C. abortus and C. pecorum from faecal samples of lambs at three sampling times (weaning, post-weaning and pre-slaughter) from eight farms in South Australia, New South Wales, Victoria and Western Australia. A total of 3412 faecal samples were collected and screened from approximately 1189 lambs across the four states. C. abortus was not detected in any of the samples screened. The overall prevalence of C. pecorum was 1027/3412 (30.1%) and median bacterial concentrations at weaning, post-weaning and pre-slaughter were 1.8 × 10(7), 1.2 × 10(7) and 9.6 × 10(5)/g faeces, respectively. A subset of C. pecorum positive samples from each farm, (n = 48) was sequenced to confirm their identity. The present study demonstrates that C. pecorum is prevalent in Australian sheep, highlighting a need for further research on the impact of this bacterium on production.
authors: School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia.
authors: Rongchang
authors: R
authors: Yang
authors: School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia.
authors: Caroline
authors: C
authors: Jacobson
authors: School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia.
authors: Graham
authors: G
authors: Gardner
authors: South Australian Research and Development Institute, 33 Flemington Street, Glenside, SA 5065, Australia.
authors: Ian
authors: I
authors: Carmichael
authors: Faculty of Veterinary Science, University of Melbourne, 250 Princes Highway, Werribee, Vic. 3030, Australia.
authors: Angus J D
authors: AJ
authors: Campbell
authors: School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia. Electronic address: una.ryan@murdoch.edu.au.
authors: Una
authors: U
authors: Ryan
mesh_terms: D000818:Animals; D001315:Australia / Q000453:epidemiology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D057138:Bacterial Shedding; D002689:Chlamydia / Q000302:isolation & purification*; D002690:Chlamydia Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D005260:Female; D016133:Polymerase Chain Reaction / Q000662:veterinary; D015995:Prevalence; D012621:Seasons; D012756:Sheep; D012757:Sheep Diseases / Q000453:epidemiology* / Q000382:microbiology; D013045:Species Specificity
chemical_list: D001425:Bacterial Outer Membrane Proteins; C078167:OMPA outer membrane proteins
keywords: Chlamydia pecorum; Lambs; Prevalence; Quantitative PCR; ompA