The Effect of Dietary Supplementation with Spent Cider Yeast on the Swine Distal Gut Microbiome

peer-reviewedBackground: There is an increasing need for alternatives to antibiotics for promoting animal health, given the increasing problems associated with antibiotic resistance. In this regard, we evaluated spent cider yeast as a potential probiotic for modifying the gut microbiota in weanling pigs using pyrosequencing of 16S rRNA gene libraries. Methodology and Principal Findings: Piglets aged 24–26 days were assigned to one of two study groups; control (n = 12) and treatment (n = 12). The control animals were fed with a basal diet and the treatment animals were fed with basal diet in combination with cider yeast supplement (500 ml cider yeast containing ,7.6 log CFU/ml) for 21 days. Faecal samples were collected for 16s rRNA gene compositional analysis. 16S rRNA compositional sequencing analysis of the faecal samples collected from day 0 and day 21 revealed marked differences in microbial diversity at both the phylum and genus levels between the control and treatment groups. This analysis confirmed that levels of Salmonella and Escherichia were significantly decreased in the treatment group, compared with the control (P,0.001). This data suggest a positive influence of dietary supplementation with live cider yeast on the microbial diversity of the pig distal gut. Conclusions/Significance: The effect of dietary cider yeast on porcine gut microbial communities was characterized for the first time using 16S rRNA gene compositional sequencing. Dietary cider yeast can potentially alter the gut microbiota, however such changes depend on their endogenous microbiota that causes a divergence in relative response to that given diet.This work was funded by Enterprise Ireland, under the Commercialisation Fund (Contract No: CFTD/05/117), the Irish Government under the National Development Plan, 2000–2006, the European Research and Development Fund and Science Foundation Ireland (SFI).European Research and Development Fun

Development of a luciferase-based reporter system to monitor Bifidobacterium breve UCC2003 persistence in mice

<p>Abstract</p> <p>Background</p> <p>Probiotics such as bifidobacteria have been shown to maintain a healthy intestinal microbial balance and help protect against infections. However, despite these benefits, bifidobacteria still remain poorly understood at the biochemical, physiological and especially the genetic level. Herein we describe, for the first time, the development of a non-invasive luciferase-based reporter system for real-time tracking of <it>Bifidobacterium </it>species <it>in vivo</it>.</p> <p>Results</p> <p>The reporter vector pLuxMC1 is based on the recently described theta-type plasmid pBC1 from <it>B. catenatulatum </it><abbrgrp><abbr bid="B1">1</abbr></abbrgrp> and the <it>luxABCDE </it>operon from pPL2lux <abbrgrp><abbr bid="B2">2</abbr></abbrgrp>. Derivatives of pLuxMC1, harbouring a bifidobacterial promoter (pLuxMC2) as well as a synthetically derived promoter (pLuxMC3) <abbrgrp><abbr bid="B3">3</abbr></abbrgrp> placed upstream of <it>luxABCDE</it>, were constructed and found to stably replicate in <it>B. breve </it>UCC2003. The subsequent analysis of these strains allowed us to assess the functionality of pLuxMC1 both <it>in vitro </it>and <it>in vivo</it>.</p> <p>Conclusion</p> <p>Our results demonstrate the potential of pLuxMC1 as a real-time, non-invasive reporter system for <it>Bifidobacterium</it>. It has also allowed us, for the first time, to track the colonisation potential and persistence of this probiotic species in real time. An interesting and significant outcome of the study is the identification of the caecum as a niche environment for <it>B. breve </it>UCC2003 within the mouse gastrointestinal tract (GI) tract.</p

NASA Plum Brook Station In-Space Propulsion Facility Test Stand Characterization Hot Fire Test

A test facility modification to enable small scale altitude propulsion testing at the NASA Glenn Research Center's In-Space Propulsion (ISP) Facility was verified with a hot fire test campaign. As the facility's primary steam supply system undergoes refurbishment, the alternate facility configuration, known as the "vacuum accumulator" mode, would enable rocket engine testing up to 10,000 lbf thrust. The NASA Johnson Space Center developed the vehicle for the verification test campaign: the Integrated Cryogenic Propulsion Test Article (ICPTA). Constructed primarily from assets of the former Morpheus Project, the ICPTA provided an integrated liquid oxygen (LOX) / liquid methane (LCH4) propulsion system including a 2,800 lbf thrust main engine. The ISP Facility's vacuum accumulator configuration leveraged the large test volume of the facility and a diffuser insert to maintain altitude conditions. During hot fire, the ICPTA main engine "started" the diffuser insert constructed for the test campaign. As a result, the test chamber upstream of the diffuser insert remained at altitude conditions throughout the hot fire. Upon engine shut down, a backflow deflector mitigated blow back into the test chamber by restricting the mass flow and redirecting it away from the test article. The test campaign successfully characterized the performance of the vacuum accumulator configuration. In addition, it provided an opportunity to collect data for an integrated LOX / LCH4 propulsion system in an altitude and thermal vacuum environment

Space Propulsion Research Facility (B-2): An Innovative, Multi-Purpose Test Facility

The Space Propulsion Research Facility, commonly referred to as B-2, is designed to hot fire rocket engines or upper stage launch vehicles with up to 890,000 N force (200,000 lb force), after environmental conditioning of the test article in simulated thermal vacuum space environment. As NASA s third largest thermal vacuum facility, and the largest designed to store and transfer large quantities of propellant, it is uniquely suited to support developmental testing associated with large lightweight structures and Cryogenic Fluid Management (CFM) systems, as well as non-traditional propulsion test programs such as Electric and In-Space propulsion. B-2 has undergone refurbishment of key subsystems to support the NASA s future test needs, including data acquisition and controls, vacuum, and propellant systems. This paper details the modernization efforts at B-2 to support the Nation s thermal vacuum/propellant test capabilities, the unique design considerations implemented for efficient operations and maintenance, and ultimately to reduce test costs

Anti-Salmonella lacatic acid bacteria from porcine intestinal sources

The aim of this study was to isolate lactic acid bacteria (LAB) with anti-Salmonella activity from the porcine gastrointestinal tract (GIT) and to characterise these for potentially probiotic properties using in vitro assays. Porcine caecal and faecal samples were screened for the presence of anti-Salmonella LAB; the ten most promising isolates belonged to the genera Lactobacillus and Pediococcus. The LAB exhibited large variation in their ability to survive in simulated gastric juice at pH 1.85. While Lactobacillus acidophilus species survived at up to 80% for 30 min, Lb. pentosus species declined to less than 0.001%. All isolates tolerated porcine bile at a concentration of 0.3%, with some capable of growth in the presence of up to 5% bile. The ability of the LAB isolates to prevent Salmonella invasion of intestinal epithelial cells varied, with reductions of 55% (Lb. acidophilus spp.) to 82% (Lb. salivarius spp.) observed. The data demonstrates that some porcine intestinal LAB isolates may offer potential as probiotics for the reduction of Salmonella carriage in pigs

Performance of anti-Salmonella lactic acid bacteria in the porcine intestine

Of five anti-Salmonella porcine cultures administered to pigs at 1010 cfu/day, two Lactobacillus murinus strains demonstrated superior survival during gastrointestinal transit. Both were detected at ~107 -108 cfu/g faeces which was higher (P\u3c0.05) than Pediococcus pentosaceus DPC6006 (~105 cfu/g). One Lb. murinus strain was also excreted at higher numbers (P\u3c0.05) than either Lb. salivarius DPC6005 or Lb. pentosus DPC6004 (both ~106 cfu/g). The Lb. murinus strains persisted in both the faeces and the caecum for at least 9 days post-administration. Animals fed a combination of all five strains at 1010 cfu/day excreted ~107 cfu/g of the administered strains, which was higher (P\u3c0.05) than only P. pentosaceus DPC6006. Randomly amplified polymorphic DNA (RAPD) PCR analysis revealed that both Lb. murinus strains predominated in the faeces of these animals during administration, while post-administration, both Lb. murinus strains and Lb. pentosus DPC6004 were recovered from the faeces and the caecum while P. pentosaceus DPC6006 was only detected in the caecum. After 21 days of culture administration, faecal Enterobacteriaceae counts were reduced in pigs fed Lb. salivarius DPC6005, P. pentosaceus DPC6006, Lb. pentosus DPC6004 and the culture mix, though not significantly. Overall, the porcine intestinal isolates offer potential as probiotics for enteropathogen reduction in pigs; possibly as a combination due to strain variation

NASA Plum Brook Station Spacecraft Propulsion Research Facility (B-2): An Innovative Multi-Purpose Test Facility

No abstract availabl

Selection of porcine intestinal isolates as probiotics for pathogen reduction in pigs

Putative lactobacilli were isolated from the porcine small intestine and assessed in vitro for potential probiotic traits. Viability of all isolates tested was unaffected at porcine bile concentrations of 0.3 % (w/v), with some tolerating up to 3.5 % (w/v) bile. Randomly amplified polymorphic DNA (RAPD) and/or pulsed field gel electrophoresis (PFGE) were used to genetically fingerprint the porcine isolates. Some of these cultures demonstrated antagonistic activity against pathogens Escherichia coli O157:H45 and Salmonella typhimurium DT104 when assayed on agar plates and in co-culture. For example, no Salmonella were detected after 8 h of associative culture with one intestinal isolate,L. salivarius B-24. However, when co-cultured under constant pH conditions, no inhibition was observed, indicating that acid may be one of the mechanisms involved in the antimicrobial activity of this strain. Assessment of these strains is on-going with a view to the development of probiotic feed additives which could potentially reduce pathogen carriage in pigs

Deep sequencing analysis of mutations resulting from the incorporation of dNTP analogs

Next-generation DNA sequencing technology was used to score >100 000 mutations resulting from exposure of a nucleic acid template to a mutagenic dNTP analog during a single pass of a DNA polymerase. An RNA template of known secondary structure was reverse transcribed in the presence of 8-oxo-dGTP, dPTP or both, followed by forward transcription in the presence of standard NTPs. Each mutagen, whether used alone or in combination, resulted in a highly characteristic mutation profile. Mutations were generated at a mean frequency of 1–2% per eligible nucleotide position, but there was substantial variation in the frequency of mutation at different positions, with a SD close to the mean. This variation was partly due to the identity of the immediately surrounding nucleotides and was not significantly influenced by the secondary structure of the RNA template. Most of the variation appears to result from idiosyncratic features that derive from local sequence context, demonstrating how different genetic sequences have different chemical phenotypes