and PCR Screening for a Live Attenuated Typhimurium Vaccine Strain.

The application of live attenuated Typhimurium vaccines has significantly helped control in poultry products. Because the U.S.

Growth assessment of Salmonella enterica multi-serovar populations in poultry rinsates with commonly used enrichment and plating media.

Isolation of Salmonella from enrichment cultures of food or environmental samples is a complicated process. Numerous factors including fitness in various selective enrichment media, relative starting concentrations in pre-enrichment, and competition among multi-serovar populations and associated natural microflora, come together to determine which serovars are identified from a given sample. A recently developed approach for assessing the relative abundance (RA) of multi-serovar Salmonella populations (CRISPR-SeroSeq or Deep Serotyping, DST) is providing new insight into how these factors impact the serovars observed, especially when different selective enrichment methods are used to identify Salmonella from a primary enrichment sample.

Poultry Processing Interventions Reduce Salmonella Serovar Complexity on Postchill Young Chicken Carcasses as Determined by Deep Serotyping.

Nearly 20% of salmonellosis cases are attributed to broilers, with renewed efforts to reduce Salmonella during broiler production and processing. A limitation to Salmonella culture is that often a single colony is picked for characterization, favoring isolation of the most abundant serovar found in a sample, while low abundance serovars can remain undetected. We used a deep serotyping approach, CRISPR-SeroSeq (serotyping by sequencing the clustered regularly interspaced palindromic repeats), to assess Salmonella serovar complexity during broiler processing and to determine the impact of antimicrobial interventions upon serovar population dynamics.

Combined Quantification and Deep Serotyping for Salmonella Risk Profiling in Broiler Flocks.

Despite a reduction of Salmonella contamination on final poultry products, the level of human salmonellosis cases attributed to poultry has remained unchanged over the last few years. There needs to be improved effort to target serovars which may survive antimicrobial interventions and cause illness, as well as to focus on lessening the amount of contamination entering the processing plant. Advances in molecular enumeration approaches allow for the rapid detection and quantification of Salmonella in pre- and postharvest samples, which can be combined with deep serotyping to properly assess the risk affiliated with a poultry flock.

Regional Differences in United States Broiler Production from 2016 to 2020 and the Contribution of Multiserovar Populations to Surveillance.

Poultry remains a considerable source of foodborne salmonellosis despite significant reduction of Salmonella incidence during processing. There are multiple entry points for Salmonella during production that can lead to contamination during slaughter, and it is important to distinguish the serovars present between the different stages to enact appropriate controls. National Salmonella data from the U.

Antimicrobial Resistance Hidden within Multiserovar Populations.

can exist in food animals as multiserovar populations, and different serovars can harbor diverse antimicrobial resistance (AMR) profiles. Conventional isolation assesses AMR only in the most abundant members of a multiserovar population, which typically reflects their relative abundance in the initial sample. Therefore, AMR in underlying serovars is an undetected reservoir that can readily be expanded upon antimicrobial use.