SalmonellaOranienburg Isolated from Horses, Wild Turkeys and An Edible Home Garden Fertilized with Raw Horse Manure

Abstract

Summary In July 2010, a horse from a rural farm (Farm A) in coastal Northern California was diagnosed with Salmonella Oranienburg infection following referral to a veterinary hospital for colic surgery. Environmental sampling to identify potential sources and persistence of Salmonella on the farm was conducted from August 2010 to March 2011. Salmonella was cultured using standard enrichment and selective plating. Pure colonies were confirmed by biochemical analysis, serotyped and compared by pulsed‐field gel electrophoresis (PFGE) analysis. A total of 204 clinical and environmental samples at Farm A were analysed, and Salmonella spp. was isolated from six of eight (75%) horses, an asymptomatic pet dog, two of seven (28.6%) water samples from horse troughs, nine of 20 (45%) manure storage pile composites, 16 of 71 (22.5%) wild turkey faeces and four of 39 (10.3%) soil samples from the family's edible home garden. Well water and garden vegetable samples and horse faecal samples from a neighbouring ranch were negative. S. Oranienburg with a PFGE pattern indistinguishable from the horse clinical strain was found in all positive sample types on Farm A. The investigation illustrates the potential for widespread dissemination of Salmonella in a farm environment following equine infections. We speculate that a recent surge in the wild turkey population on the property could have introduced S. Oranienburg into the herd, although we cannot rule out the possibility wild turkeys were exposed on the farm or to other potential sources of Salmonella. Findings from the investigation indicated that raw horse manure applied as fertilizer was the most likely source of garden soil contamination. Viable S. Oranienburg persisted in garden soil for an estimated 210 days, which exceeds the 120‐day standard between application and harvest currently required by the National Organic Program. The study underscores the need to educate the public about potential food safety hazards associated with using raw animal manure to fertilize edible home gardens.

Salmonella entericaSerovar Oranienburg Outbreak in a Veterinary Medical Teaching Hospital with Evidence of Nosocomial and On-Farm Transmission

“…A comparable degree of PFGE variation was detected in a recently reported outbreak of Salmonella Oranienburg among calves on a dairy farm (Kaneene et al 2010). In another recent study, isolates obtained over time from a Salmonella Oranienburg-positive horse following hospital discharge yielded four PFGE types that differed from the initial isolate subtype by one to three bands ( Jay-Russell et al 2014). The presumably rapid diversification of Salmonella PFGE types during outbreaks among humans or during environmental persistence in production or farm environments has also been reported previously (Tassios et al 2000, Martinez-Urtaza and Liebana 2005, Dunowska et al 2007, Ethelberg et al 2007, Uesugi et al 2007).…”

Salmonella Serovars Isolated from Brown Rats (Rattus norvegicus) from Grenada, West Indies: Prevalence and Antimicrobial Susceptibility

“…A serious gastrointestinal disease in humans involving S. oranienburg was reported from many countries (Denmark, Austria, Belgium, Finland, Sweden, the Netherlands and Canada) due to contamination of Chocolate produced by a company in Germany [37]. In animals infection with S. Oranienburg has been found in horses and turkeys in California [38]. In Grenada, S. orenienburg has not been isolated previously.…”

Perspectives and safety of horsemeat consumption

“…Salmonella spp. have also been detected in equine faeces (Jay‐Russell et al , ). Therefore, there is a potential food safety risk from using raw horse manure to fertilise edible plant products.…”