Yeast Fermentate-Mediated Reduction of Salmonella Reading and Typhimurium in an in vitro Turkey Cecal Culture Model.
ABSTRACT: Salmonella Reading is an ongoing public health issue in the turkey industry, leading to significant morbidity in humans in the United States. Pre-harvest intervention strategies that contribute to the reduction of foodborne pathogens in food animals, such as the yeast fermentation metabolites of Original XPCTM (XPC), may become the key to multi-hurdle farm to fork strategies. Therefore, we developed an anaerobic in vitro turkey cecal model to assess the effects of XPC on the ceca of commercial finisher tom turkeys fed diets void of XPC and antibiotics. Using the in vitro turkey cecal culture method, ceca were tested with and without XPC for their anti-Salmonella Reading and the previously defined anti-Typhimurium (ST97) effects. Ultimately, the anti-Salmonella effects were independent of serovar (P > 0.05). At 0 h post inoculation (hpi), Salmonella levels were equivalent between treatments at 7.3 Log10 CFU/mL, and at 24 hpi, counts in XPC were reduced by 5 Log10 CFU/mL, which was 2.1 Log10 lower than the control (P < 0.05). No differences in serovar prevalence existed (P > 0.05), with a 92% reduction in Salmonella positive XPC-treated ceca cultures by 48 hpi (P < 0.05). To evaluate changes to the microbiota independent of the immune response, the 16S rDNA was sequenced using the Illumina MiSeq platform. Data indicated a profound effect of time and treatment for the reduction of Salmonella irrespective of serovar. XPC sustained diversity metrics compared to the control, demonstrating a reduction in diversity over time (Q < 0.05).
Project description:The small-scale mobile poultry-processing unit (MPPU) produced raw poultry products are of particular food safety concern due to exemption of USDA poultry products inspection act. Limited studies reported the microbial quality and safety of MPPU-processed poultry carcasses. This study evaluated the <i>Salmonella</i> and <i>Campylobacter</i> prevalence in broiler ceca and on MPPU-processed carcasses and efficacy of commercial antimicrobials against <i>Campylobacter jejuni</i> on broilers. In study I, straight-run Hubbard?×?Cobb broilers (147) were reared for 38?days on clean-shavings (CS, 75) or built-up-litter (BUL, 72) and processed at an MPPU. Aerobic plate counts (APCs), coliforms, <i>Escherichia coli</i>, and yeast/molds (Y/M) of carcasses were analyzed on petrifilms. Ceca and carcass samples underwent microbial analyses for <i>Salmonella</i> and <i>Campylobacter</i> spp. using the modified USDA method and confirmed by API-20e test (<i>Salmonella</i>), latex agglutination immunoassay (<i>Campylobacter</i>), and Gram staining (<i>Campylobacter</i>). Quantitative polymerase chain reaction (CadF gene) identified the prevalence of <i>C. jejuni</i> and <i>Campylobacter coli</i> in ceca and on carcasses. In study II, fresh chilled broiler carcasses were spot inoculated with <i>C. jejuni</i> (4.5?log<sub>10</sub>?CFU/mL) and then undipped, or dipped into peroxyacetic acid (PAA) (1,000?ppm), lactic acid (5%), lactic and citric acid blend (2.5%), sodium hypochlorite (69?ppm), or a H<sub>2</sub>O<sub>2</sub>-PAA mix (SaniDate<sup>®</sup> 5.0, 0.25%) for 30?s. Surviving <i>C. jejuni</i> was recovered onto Brucella agar. APCs, coliforms, and <i>E. coli</i> populations were similar (<i>P</i>?>?0.05) on CS and BUL carcasses. Carcasses of broilers raised on BUL contained a greater (<i>P</i>?<?0.05) Y/M population (2.2?log<sub>10</sub>?CFU/mL) than those reared on CS (1.8?log<sub>10</sub>?CFU/mL). <i>Salmonella</i> was not detected in any ceca samples, whereas 2.8% of the carcasses from BUL were present with <i>Salmonella</i>. Prevalence of <i>Campylobacter</i> spp., <i>C. jejuni</i> was lower (<i>P</i>?<?0.05), and <i>C. coli</i> was similar (<i>P</i>?>?0.05) in CS-treated ceca than BUL samples. Prevalence of <i>Campylobacter</i> spp., <i>C. jejuni</i>, and <i>C. coli</i> was not different (<i>P</i>?>?0.05) on CS- and BUL-treated carcasses. All antimicrobials reduced <i>C. jejuni</i> by 1.2-2.0?log CFU/mL on carcasses compared with controls. Hence, raising broilers on CS and applying post-chilling antimicrobial treatment can reduce <i>Salmonella</i> and <i>Campylobacter</i> on MPPU-processed broiler carcasses.
Project description:Previous studies have shown a tissue immune phenotype-altering event occurring on days 2 and 4 in the ceca post-<i>Salmonella</i> challenge. To evaluate the involvement of the cecal microbiota in the phenotype reprogramming, we hypothesized that the addition of subtherapeutic bacitracin (BMD) will affect the cecal microbiota. Therefore, the objective of this study was to determine if the antibiotic-mediated changes in the microbiota composition influenced the immune phenotype induced by <i>Salmonella enteritidis</i> infection of the chicken cecum. A total of 112 fertile eggs were obtained for each experiment, repeated for a total of three separate times. The ceca and cecal contents were collected on days 2 and 4 post-infection for mRNA expression TaqMan assay and 16S rRNA gene microbiota sequencing. The results demonstrate the effects of bacitracin on cecal composition and its interaction with <i>Salmonella enteritidis</i> in young chicks. There is a preliminary indication of phenotype change in the <i>Salmonella</i>-challenged group provided subtherapeutic BMD due to the shifting cecal microbiota and cecal immune response, indicating the addition of bacitracin during infection altered the cecal phenotype. These data demonstrate the potential involvement of the microbiota in reprogramming immune phenotype (disease resistance to disease tolerance) induced by <i>Salmonella</i> in the chicken cecum.
Project description:Bdellovibrio bacteriovorus is a bacterium which preys upon and kills Gram-negative bacteria, including the zoonotic pathogens Escherichia coli and Salmonella. Bdellovibrio has potential as a biocontrol agent, but no reports of it being tested in living animals have been published, and no data on whether Bdellovibrio might spread between animals are available. In this study, we tried to fill this knowledge gap, using