Detection of Chlamydiaceae in ocular swabs from Australian pre-export feedlot sheep.
Chlamydia
Chlamydia pecorum
Chlamydia psittaci
Infectious keratoconjunctivitis
Sheep
species-specific qPCR
Journal
Australian veterinary journal
ISSN: 1751-0813
Titre abrégé: Aust Vet J
Pays: England
ID NLM: 0370616
Informations de publication
Date de publication:
Oct 2019
Oct 2019
Historique:
received:
14
11
2018
revised:
14
05
2019
accepted:
16
06
2019
pubmed:
10
7
2019
medline:
22
1
2020
entrez:
10
7
2019
Statut:
ppublish
Résumé
Infectious Ovine Keratoconjunctivitis (IOK) is a contagious ocular disease of sheep. A range of organisms have been observed as the aetiological agents of IOK. In this study, the presence of chlamydial pathogens (C. pecorum, C. abortus, C. psittaci) in conjunctival swabs was tested for. The swabs were collected from sheep with varying grades of IOK in an Australian pre-export feedlot. The sheep had been rejected from a shipment because of the eye disease. The relative contribution of chlamydial pathogens to IOK and the rejection of animals was evaluated. In total, 149 conjunctival swabs were taken from rejected sheep (IOK Grades 1 to 6; n = 126) as well as those with healthy eyes (Grade 0; n = 23). Screening for chlamydial pathogens was done using species-specific qPCR assays. Chlamydial DNA was detected in 35.6% (53/149) of conjunctival samples. C. pecorum was the most predominant species with an overall prevalence of 28.9% (43/149). C. psittaci prevalence was 6.7% (10/149). Both organisms were detected in healthy as well as IOK-affected eyes. All swabs tested negative for C. abortus. The results from this study demonstrate that Chlamydia spp can be readily detected in sheep presenting with IOK. The zoonotic C. abortus was not detected in any of the samples in this study, providing further evidence to the suggestion that this pathogen remains absent from Australia. Although the exact contribution of Chlamydia spp in the IOK pathogenesis is unclear, such studies are anticipated to be of benefit to Australian domestic and live export production systems.
Types de publication
Case Reports
Comparative Study
Langues
eng
Sous-ensembles de citation
IM
Pagination
401-403Subventions
Organisme : Australian Research Council
ID : LP160101599
Informations de copyright
© 2019 Australian Veterinary Association.
Références
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