Survival of Salmonella in Various Wild Animal Feces That May Contaminate Produce

Abstract

Heightened concerns about wildlife on produce farms and possible introduction of pathogens to the food supply have resulted in required actions following intrusion events. The purpose of this study was to evaluate the survival of Salmonella in feces from cattle and various wild animals (feral pigs, waterfowl, deer, and raccoons) in California, Delaware, Florida, and Ohio. Feces were inoculated with rifampin-resistant Salmonella enterica cocktails that included six serotypes: Typhimurium, Montevideo, Anatum, Javiana, Braenderup, and Newport (104 to 106 CFU/g). Fecal samples were stored at ambient temperature. Populations were enumerated for up to 1 year (364 days) by spread plating onto tryptic soy agar supplemented with rifampin. When no colonies were detected, samples were enriched. Colonies were banked on various sampling days based on availability of serotyping in each state. During the 364-day storage period, Salmonella populations decreased to ≤2.0 log CFU/g by day 84 in pig, waterfowl, and raccoon feces from all states. Salmonella populations in cattle and deer feces were 3.3 to 6.1 log CFU/g on day 336 or 364; however, in Ohio Salmonella was not detected after 120 days. Salmonella serotypes Anatum, Braenderup, and Javiana were the predominant serotypes throughout the storage period in all animal feces and states. Determination of appropriate risk mitigation strategies following animal intrusions can improve our understanding of pathogen survival in animal feces. HIGHLIGHTS

Risk factors associated with the prevalence of Shiga-toxin-producing Escherichia coli in manured soils on certified organic farms in four regions of the USA

“…The FSMA-PSR includes language for prevention of contamination and risk mitigation; however, this is based on individual farm assessments, which may vary from grower to grower and may be landscape-specific (FDA, 2015). Determining adequate no-harvest buffers around in-field fecal material is necessary in order to avoid the contamination of fresh produce by foodborne pathogens (Salmonella, E. coli, and E. coli O157:H7), which depends on fecal sources, irrigation, and splash events (Atwill et al, 2015;Weller et al, 2017;Topalcengiz et al, 2020). An experimental study conducted in the Northeastern United States showed E. coli levels on lettuce and lettuce-feces distance were negatively correlated, when using a buffer smaller or equal to 1 meter during foliar regulation (Weller et al, 2017).…”

Quantification of Salmonella Infantis transfer from transport drawer flooring to broiler chickens during holding

“…Few studies have reported the efficacy of such cleaning procedures in reducing Salmonella levels ( Hinojosa et al, 2018 ), and unfortunately, they cannot be directly compared with the reductions observed for Campylobacter . Both of these pathogens have different morphologies, different growing requirements, and even different survivals rates outside their natural hosts ( Jay, 1998 ; Cebrián et al, 2017 ; Topalcengiz et al, 2020 ). Consequently, these different factors result in the creation of a unique risk profile for each one of these pathogens ( Slader et al, 2002 ; De Cesare et al, 2003 ; McCrea et al, 2006 ).…”

Tell me if you prefer bovine or poultry sectors and I’ll tell you who you are: Characterization of Salmonella enterica subsp. enterica serovar Mbandaka in France

“…Furthermore, recent studies conducted in the United States and Japan on the persistence of Salmonella in feces from bovines and various wild animals (crows, deer, feral pigs, raccoons, and waterfowl) have shown that wild animals can also represent a risk of contamination for producers. Salmonella can in fact survive in feces for several months and contaminate the farm environment and pastures ( Topalcengiz et al, 2020 ; Yamaguchi et al, 2022 ).…”