Genomic Insights into Multidrug-Resistant Salmonella in Australian thoroughbreds

Summary

Salmonella enterica is the most important contagious enteropathogen of horses of all ages, causing diarrhoea, colic, systemic illness and death. Salmonella is a zoonotic pathogen and a major cause of human disease, worldwide. There are over 2600 Salmonella serotypes and this species exhibits substantial genetic diversity in virulence factors (VF) and antimicrobial resistance (AMR), with impact on infectivity, pathogenicity and disease severity/type in infected horses and humans.

Determination of VF and AMR genes in Salmonella serotypes of relevance in horses, particularly predominant serotypes, will enhance understanding of key factors for disease in horses and risk of zoonotic infection. In this study, whole genome sequencing (WGS) will be used to characterise and compare the genomics of the two predominant serotypes of Salmonella in Australian horses (S. Muenster and S.Typhimurium). S.Muenster is multidrug resistant, including to drugs of critical importance to human health. In horses, infection with S. Typhimurium is associated with increased odds of death, in comparison to other serotypes. Collectively, these 2 serotypes are responsible for >80% of horse infections in Australia. However, there is a lack of information on the genetics of these serotypes, precluding advances in disease control. Fifty Salmonella isolates collected and stored in AgriFutures-funded project (PRO-015534) will have DNA extracted and undergo WGS at the Australian Genome Research Facility. The WGS data will be used for bioinformatics analysis to determine the VF and AMR genomic profiles of the serotypes, compare between serotypes and determine any temporal genomic change within these serotypes of importance.

Program

Thoroughbred Horses

Research Organisation

Charles Sturt University

Objective Summary

As above