He is currently collaborating with the University of Sydney to investigate improved and enhanced direct diagnosis tests of pathogens that affect terrestrial and aquatic species and the University of the Sunshine Coast focusing on Chlamydiosis in production animals.
The majority of Ian's research has focused on Johne’s disease but other areas his has been active in include; viral diseases of finfish, parasitic diseases of oysters and epidemiological modelling on the effects of exotic disease outbreaks which has resulted in many peer-reviewed journal articles in journals such as Molecular and Cellular Probes, Journal of Clinical Microbiology and the Journal of Bacteriology. Ian has worked closely with colleagues on the development of the Australian and New Zealand Standard Diagnostic Procedures for Johnes Disease and has made significant contributions to the World Organisation of Animal Health (OIE) chapters on Johne’s disease and Epizootic haematopoietic necrosis virus.
Ian undertook his Bachelor of Technology Management (Biotechnology) (First Class Honours) at the University of Western Sydney, Macarthur and then a PhD at the University of Sydney in the Faculty of Veterinary Science.
Ian will be presenting (with Katie Eager) on: Molecular diagnostics from the veterinary laboratory perspective, to sequence or not to sequence.
Whilst molecular-based technology has vastly improved our diagnostic capabilities for many veterinary pathogens, some still remain difficult to detect and characterise including a number of intracellular bacteria. This can be further complicated when these pathogens are exotic and/or zoonotic and/or notifiable. A rapid and accurate diagnosis is critical to the decisions that follow and the actions taken on farm or in the laboratory. The World Organisation for Animal Health (OIE) states it “would be good practice to” include a subsequent sequencing step to confirm PCR positive results, especially when index cases from a previously unaffected location or weak positives are detected in qPCR. We describe the development of new qPCR-based tests that combined with desktop pyrosequencing will markedly reduce the time required to accurately detect and characterise veterinary pathogens.
Plain, K.M.*, Marsh, I.B.*, Waldron, A.M., Galea, F., Whittington, A.M., Saunders, V.F., Begg, D.J., de Silva, K., Purdie, A.C., Whittington, R.J. (2014). High-throughput direct fecal PCR assay for detection of Mycobacterium avium subsp. paratuberculosis in sheep and cattle. Journal of Clinical Microbiology 52:745-757. *Co-first author
Spiers,Z.B., Gabor,M., Fell,S.A., Carnegie,R.B., Dove,M., O'Connor,W., Frances,J., Go, J., Marsh, I.B., Jenkins, C. (2014). Longitudinal study of winter mortality disease in Sydney rock oysters, Saccostrea glomerata. Diseases of Aquatic Organisms 110:151-64.
Ward, M.P., Cowled, B.D., Galea, F., Garner, M.G., Laffan, S.W., Marsh, I., Negus, K., Sarre, S.D., Woolnough, A.P. (2013). Salmonella infection in a remote, isolated wild pig population. Veterinary Microbiology. 162:921-929.
Marsh, I. B., Whittington, R.J. (2007). Genomic diversity in Mycobacteriumavium: single nucleotide polymorphisms between the S and C strains of M.avium subsp. paratuberculosis and with M. a. avium. Molecular and Cellular Probes 21:66-75.
Marsh, I. B., Bannantine, J. P., Paustian, M.L., Tizard, M.L., Kapur, V., Whittington, R.J. (2006). Genomic comparison of Mycobacterium avium subsp. paratuberculosis sheep and cattle strains by microarray hybridization. Journal of Bacteriology 188:2290-2293.
Marsh, I. B. Whittington, R.J. (2005). Deletion of an mmpL gene and multiple associated genes from the genome of the S strain of Mycobacterium avium subsp. paratuberculosis identified by representational difference analysis and in silico analysis. Molecular and Cellular Probes 19:371-84.