Prevalence of canine haemotropic mycoplasma infections in Sydney, Australia
- N. J. L. Hetzel, BVSc, BSc, CertSAM1,
- E. N. Barker, BVSc, BSc, PhD1,
- C. R. Helps, BSc, PhD1,
- S. Tasker, BVSc, BSc, DSAM, DipECVIM, PhD1,
- A. Arteaga, DVM, CertSAM2,
- V. R. Barrs, BVSc, MVetClinStud, FANZCVSc (Feline med)2 and
- J. Beatty, BSc, BVetMed, PhD, FANZCVSc (Feline med)2
- 1School of Veterinary Sciences, University of Bristol, Langford House, Bristol BS40 5DU, UK
- 2Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
- E-mail for correspondence:
Haemotropic mycoplasmas (haemoplasmas) are epierythrocytic, wall-less bacteria that cannot be cultivated in vitro (Messick 2003). Two species have been identified in dogs: Mycoplasma haemocanis (Mhc) and ‘Candidatus Mycoplasma haematoparvum’ (CMhp) (Messick and others 2002, Sykes and others 2004). Rhipicephalus sanguineus has been proposed as a tick vector (Seneviratna and others 1973, Novacco and others 2010) and is endemic in Australia (Roberts 1970).
Real-time quantitative polymerase chain reaction (qPCR) assays have been used to examine the prevalence of haemoplasmas in several locations worldwide (Kenny and others 2004, Sasaki and others 2008, Wengi and others 2008, Barker and others 2010, Roura and others 2010). The aim of this study was to determine the prevalence of and examine potential risk factors for haemoplasma infection in dogs in Sydney, Australia, using qPCR.
Residual EDTA anti-coagulated blood samples (n = 281) were available (with owner consent) from 271 dogs presenting to the University of Sydney, Australia from May 2008 to September 2009. Samples were collected during investigation of a variety of conditions and transported in 96 well plates to the UK on ice. DNA was purified from 100 ∝ l blood using a commercial kit (Macherey-Nagel NucleoSpin Blood kit; ABgene). Two negative control extractions were included in each batch of 92 sample extractions.
All samples were subjected to species-specific qPCR for the detection of Mhc and CMhp, as described previously (Barker and others 2010). Each assay was duplexed with a canine glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene-specific qPCR as an internal control to monitor for extraction and/or PCR errors (Barker and …