Comparison of yeast-derived commercial feed additives on Salmonella Enteritidis survival and microbiota populations in rooster cecal in vitro incubations.

Yeast-derived products have become more of an interest in the poultry industry as of late because of their use in modulating the gastrointestinal tract (GIT) microbiome to both improve production parameters and prevent infection. This study aimed to evaluate the effects of various yeast-derived products on Salmonella enterica inoculation in un in vitro rooster cecal incubations and associated effects on the cecal microbiome. Cecal contents were obtained from 53-wk old White Leghorn H & N Nick Chick roosters (n = 3) fed a wheat-based, commercial-type basal diet. Cecal contents were diluted 1:3000 in anaerobic dilution solution (ADS) in an anaerobic chamber, with 20 mL aliquoted to each serum bottle. There were three controls (n = 3): basal diet only, diluted cecal contents only, and basal diet and diluted cecal contents; and five treatments containing the basal diet and diluted cecal contents (n = 3): Citristim® (ADM), ImmunoWall® (ICC), Maxi-Gen Plus® (CBS Bio Platforms), Hilyses® (ICC), and Original XPC® (Diamond V). All treatments were applied at a rate of 2.5 kg/tonne or less. All groups were inoculated with a nalidixic acid-resistant strain of Salmonella Enteritidis at 10^7 CFU/mL and incubated at 37 deg C. Samples were collected at 0, 24, and 48 h for S. Enteritidis enumeration and 16S rDNA microbial sequencing. Salmonella data were log-transformed and analyzed in a two-way ANOVA with means separated using Tukey's HSD (P≤0.05). Genomic DNA was extracted, and resulting libraries were prepared and sequenced using an Illumina MiSeq. Sequencing data were analyzed in QIIME2 (2021.4) with diversity metrics (alpha and beta), and an analysis of the composition of microbiomes (ANCOM) was performed. Main effects were considered significant at P≤0.05, with pairwise differences considered significant at Q≤0.05. There was an interaction of treatment and time on the enumeration of Salmonella where treatments of Citristim, Immunowall, Hilyses, and XPC reduced Salmonella by 1 log CFU/mL compared to the controls. At 48 h, each yeast product treatment reduced Salmonella by 3 log CFU/mL compared to the controls. There was no main effect of treatment on the alpha diversity metrics, richness, or evenness (P > 0.05). Treatment affected the beta diversity, abundance, and phylogenetic differences, but there were no pairwise differences (P>0.05, Q>0.05). Using ANCOM at the genus level, the taxa Synergistes, Alloprevotella, Sutterella, and Megasphaera abundance were significantly different (W = 154,147,145,140, respectively). These results demonstrate the potential of these yeast-derived products to reduce foodborne pathogens, such as Salmonella Enteriditis, in vitro, without negatively disrupting the cecal microbiome.

Mitigating the attachment of Salmonella Infantis on isolated poultry skin with cetylpyridinium chloride.

To provide the poultry industry with effective mitigation strategies, the effects of cetylpyridinium chloride (CPC) on the reduction of Salmonella Infantis, hilA expression, and chicken skin microbiota were evaluated. Chicken breast skins (4×4 cm; N = 100, n = 10, k = 5) were inoculated with Salmonella (Typhimurium or Infantis) at 4°C (30min) to obtain 108 CFU/g attachment. Skins were shaken (30s), with remaining bacteria being considered firmly attached. Treatments were applied as 30s dips in 50 mL: no inocula-no-treatment control (NINTC), no treatment control (NTC), tap water (TW), TW+600 ppm PAA (PAA), or TW+0.5% CPC (CPC). Excess fluid was shaken off (30s). Samples were homogenized in nBPW (1 min). Samples were discarded. Salmonella was enumerated and Log10 transformed. Reverse transcriptase-qPCR (rt-qPCR) was performed targeting hilA gene and normalized using the 2-ΔΔCt method. Data were analyzed using one-way ANOVA in RStudio with means separated by Tukey's HSD (P≤0.05). Genomic DNA of rinsates was extracted, 16S rRNA gene (V4) was sequenced (MiSeq), and data analyzed in QIIME2 (P≤0.05 and Q≤0.05). CPC and PAA affected Salmonella levels differently with CPC being effective against S. Infantis compared to TW (P<0.05). Treatment with CPC on S. Infantis-infected skin altered the hilA expression compared to TW (P<0.05). When inoculated with S. Typhimurium, there was no difference between the microbiota diversity of skins treated with PAA and CPC; however, when inoculated with S. Infantis, there was a difference in the Shannon's Entropy and Jaccard Dissimilarity between the two treatments (P<0.05). Using ANCOM at the genus level, Brochothrix was significant (W = 118) among skin inoculated with S. Typhimurium. Among S. Infantis inoculated, Yersiniaceae, Enterobacterales, Lachnospiraceae CHKCI001, Clostridia vadinBB60 group, Leuconostoc, Campylobacter, and bacteria were significant (408). CPC and PAA-treated skins had lowest relative abundance of the genera. In conclusion, CPC mitigated Salmonella Infantis, altered hilA expression, and influenced the chicken skin microbiota.

Practical opportunities for microbiome analyses and bioinformatics in poultry processing.

Poultry processing is undergoing changes both in operations as well as microbial methodologies. Traditionally, microbial data has been gathered through a series of culturing methods using liquid media and plating for isolation and enumeration. Both foodborne pathogens and nonpathogenic bacterial populations are estimated to assess food safety risks as well as the potential for spoilage. Bacterial loads from carcasses are important for estimating processing control and the effectiveness of antimicrobial applications. However, these culture-based approaches may only provide part of the microbial ecology landscape associated with chicken carcasses and the subsequent changes that occur in these populations during processing. Newer molecular-based approaches, such as 16S sequencing of the microbiota, offer a means to retrieve a more comprehensive microbial compositional profile. However, such approaches also result in large data sets which must be analyzed and interpreted. As more data is generated, this will require not only bioinformatic programs to process the data but appropriate educational forums to present the processed data to a broad audience.

Improvement in rheumatic fever and rheumatic heart disease management and prevention using a health centre-based continuous quality improvement approach.

BACKGROUND: Rheumatic heart disease (RHD) remains a major health concern for Aboriginal Australians. A key component of RHD control is prevention of recurrent acute rheumatic fever (ARF) using long-term secondary prophylaxis with intramuscular benzathine penicillin (BPG). This is the most important and cost-effective step in RHD control. However, there are significant challenges to effective implementation of secondary prophylaxis programs. This project aimed to increase understanding and improve quality of RHD care through development and implementation of a continuous quality improvement (CQI) strategy. METHODS: We used a CQI strategy to promote implementation of national best-practice ARF/RHD management guidelines at primary health care level in Indigenous communities of the Northern Territory (NT), Australia, 2008-2010. Participatory action research methods were employed to identify system barriers to delivery of high quality care. This entailed facilitated discussion with primary care staff aided by a system assessment tool (SAT). Participants were encouraged to develop and implement strategies to overcome identified barriers, including better record-keeping, triage systems and strategies for patient follow-up. To assess performance, clinical records were audited at baseline, then annually for two years. Key performance indicators included proportion of people receiving adequate secondary prophylaxis (≥80% of scheduled 4-weekly penicillin injections) and quality of documentation. RESULTS: Six health centres participated, servicing approximately 154 people with ARF/RHD. Improvements occurred in indicators of service delivery including proportion of people receiving ≥40% of their scheduled BPG (increasing from 81/116 [70%] at baseline to 84/103 [82%] in year three, p = 0.04), proportion of people reviewed by a doctor within the past two years (112/154 [73%] and 134/156 [86%], p = 0.003), and proportion of people who received influenza vaccination (57/154 [37%] to 86/156 [55%], p = 0.001). However, the proportion receiving ≥80% of scheduled BPG did not change. Documentation in medical files improved: ARF episode documentation increased from 31/55 (56%) to 50/62 (81%) (p = 0.004), and RHD risk category documentation from 87/154 (56%) to 103/145 (76%) (p < 0.001). Large differences in performance were noted between health centres, reflected to some extent in SAT scores. CONCLUSIONS: A CQI process using a systems approach and participatory action research methodology can significantly improve delivery of ARF/RHD care.

An integrated system for disaster preparedness and response.

Kaiser Permanente, the USA's largest not-for-profit integrated healthcare provider, has developed a hybrid emergency preparedness and response system. It consists of a tiered structure of national 'workgroups' and traditional physical command centre operations. The workgroups provide integration and coordination across a large organisation while allowing for necessary regional operational flexibility. Workgroup membership taps the best available expertise in a functional area, drawn from all levels and all regions, so as to best represent all interests of a divergent, widespread organisation. Workgroups exist in 'standby' until a threat emerges, then are activated as needed, excepting the core clinical workgroup which meets at least monthly to track potential risks to the organisation. These workgroups promote internal consistency, represent the organisation to outside entities, and develop tools, templates and protocols that regions can adapt, adopt and implement through a traditional, operational system of regional and medical centre and clinical emergency command centres. Developed in response to the anthrax terrorism in the early 1990s, this hybrid system allowed for a rapidly escalated, yet measured response to the recent H1N1 outbreak and could be a template for application in other organisations with similar needs.

Sample-sort simulated annealing.

A simulated annealing (SA) algorithm called Sample-Sort that is artificially extended across an array of samplers is proposed. The sequence of temperatures for a serial SA algorithm is replaced with an array of samplers operating at static temperatures and the single stochastic sampler is replaced with a set of samplers. The set of samplers uses a biased generator to sample the same distribution of a serial SA algorithm to maintain the same convergence property. Sample-Sort was compared to SA by applying both to a set of global optimization problems and found to be comparable if the number of iterations per sampler was sufficient. If the evaluation phase dominates the computational requirements, Sample-Sort could take advantage of parallel processing.