Reducing the risk of food borne pathogens (Campylobacter) in pre-slaughter pigs via short-time feeding with prebiotics

Reducing the presence of human pathogens like Campylobacter and Salmonella (zoonoses) in their animal hosts is important to enhance food safety of products of animal origin. Campylobacter is considered to be a commensal in the gastrointestinal tract of pigs due to its typically high prevalence. Consequently, it is difficult to control Campylobacter in pigs at farm level by usual hygienic measures, especially in open systems of organic pig production (Jensen et al 2006). However, another potential means to control pathogens is inclusion of non-digestible oligosaccharides (prebiotics) in the diet. For example, prebiotics proofed successful in control of the intestinal disease swine dysentery caused by the spirochaete Brachyspira hyodysenteriae (Molbak et al. 2007

High diversity of salmonella serotypes found in an experiment with outdoor pigs

Little is known about the risk of Salmonella infection in outdoor pig production, but seroprevalence data has indicated a higher occurrence of Salmonella in outdoor production systems than in conventional indoor systems. This is perhaps due to the increased exposure to the surrounding environment including contact with wildlife. An unexpected high diversity of Salmonella serotypes, as e.g. S. Uganda and S. Goldcoast, which are not normally isolated from pigs, was detected in connection with an experimental study on transmission of Salmonella in outdoor organic pigs. In order to elucidate the potential source of the different Salmonella serotypes, a small-scale examination of wildlife was performed. Salmonella was not detected in any of a total of 22 rats, mice and shrews or in 21 birds (mainly crowbirds). The unidentified source of these Salmonella serotypes implies inadequate control possibilities and may therefore pose a problem for outdoor pig production in terms of food safety

Can the restricted use of antibiotics in organic pig farming be documented to provide a safer, high quality meat product with less antibiotic resistant bacteria?

The project SafeOrganic aims to document that the restricted use of antimicrobials in organic pig production leads to lower levels of antibiotic resistant bacteria compared with the level in conventional pigs. However, the project will also address the risk of losing this quality parameter, due to a widespread practice of slaughtering organic pigs together with conventional pigs, implying a risk of cross-contamination

Salmonella og Campylobacter i økologisk svineproduktion

De mere ekstensive systemer i økologisk svineproduktion formodes at have en positiv effekt på dyrenes robusthed f.eks. over for infektioner. Der er dog ingen dokumentation for, at økologiske svin har et lavere indhold af de almindelige zoonotiske bakterier som f.eks. Salmonella og Campylobacter end konventionelle svin. Et forsøg med økologiske smågrise viste, at salmonellainfektioner kan overføres både mellem grisene men også via et salmonellasmittet miljø. Graden af den smitte grisene udsættes for synes væsentlig for etablering af en infektion. Campylobacter, som anses for at være en naturlig del af grisens tarmflora, blev fundet i alle smågrisene. Desuden var det muligt at påvise både den typisk svineassocierede Campylobacter art C. coli og arten C. jejuni vha. en ny metode

The occurrence and characterization of Campylobacter jejuni and C. coli in organic pigs and their outdoor environment

The occurrence and species distribution of thermophilic Campylobacter was investigated in organic outdoor pigs. An increased exposure of outdoor pigs to C. jejuni from the environment may cause a shift from a normal dominance of C. coli to more C. jejuni, which may imply a concern of reduced food safety. Bacteriological methods for determination of Campylobacter excretion level were combined with colony-blot hybridization and real-time PCR for specific detection of C. jejuni in pigs. Campylobacter was isolated from pigs (n = 47), paddock environment (n = 126) and wildlife (n = 44), identified to species by real-time PCR and sub-typed by serotyping (Penner) and pulse-field gel electrophorsis (PFGE) genotyping. All pigs excreted Campylobacter (103–107 CFU g1 faeces) from the age of 8–13-weeks old. C. jejuni was found in 29% of pigs in three consecutive trials and always in minority to C. coli (0.3–46%). C. jejuni and C. coli were isolated from 10% and 29% of the environmental samples, respectively, while crow-birds and rats harboured C. jejuni. Individual pigs hosted several strains (up to nine serotypes). The paddock environment was contaminated with C. coli serotypes similar to pig isolates, while most of the C. jejuni serotypes differed. C. jejuni isolates of different origin comprised few similar serotypes, just one identical genotype was common between pigs, environment and birds. In conclusion, the occurrence of C. jejuni varied considerably between the three groups of outdoor pigs. Furthermore, transfer of C. jejuni to the outdoor pigs from the nearby environment was not predominant according to the subtype dissimilarities of the obtained isolates

Dynamical Organization around Turbulent Bursts

The detailed dynamics around intermittency bursts is investigated in turbulent shell models. We observe that the amplitude of the high wave number velocity modes vanishes before each burst, meaning that the fixed point in zero and not the Kolmogorov fixed point determines the intermittency. The phases of the field organize during the burst, and after a burst the field oscillates back to the laminar level. We explain this behavior from the variations in the values of the dissipation and the advection around the zero fixed point.Comment: 4 pages, REVTex, 3 figures in one ps-fil

Computing Tropical Varieties

The tropical variety of a $d$-dimensional prime ideal in a polynomial ring with complex coefficients is a pure $d$-dimensional polyhedral fan. This fan is shown to be connected in codimension one. We present algorithmic tools for computing the tropical variety, and we discuss our implementation of these tools in the Gr\"obner fan software \texttt{Gfan}. Every ideal is shown to have a finite tropical basis, and a sharp lower bound is given for the size of a tropical basis for an ideal of linear forms.Comment: 22 pages, 2 figure

The effect of a diet with fructan-rich chicory roots on intestinal helminths and microbiota with special focus on Bifidobacteria and Campylobacter in piglets around weaning

The restrictions on the use of antibiotic and anthelmintic treatments in organic pig farming necessitate alternative non-medical control strategies. Therefore, the antibiotic and parasite-reducing effect of a fructan-rich (prebiotic) diet of dried chicory was investigated in free-ranging piglets. Approximately half of 67 piglets from 9 litters were experimentally infected with Ascaris suum and Trichuris suis in the suckling period (1 to 7 weeks of age) and 58 of the piglets were challenged daily with E. coli O138:F8 for 9 days after weaning to induce weaning diarrhoea. The litters were fed either chicory (30% DM) or a control diet. The effect of chicory on intestinal helminths, intestinal microbiota, especially Bifidobacteria and Campylobacter spp., and E. coli post-weaning diarrhoea was assessed. The weight gain of the piglets was not impaired significantly by chicory. The intestinal A. suum worm burden was reduced by 64% (P=0.034) in the chicory-fed piglets, whereas these same piglets had 63% more T. suis worms (P=0.016). Feeding with chicory elicited no changes among the main bacterial groups in ileum according to terminal restriction fragment length polymorphism (T-RFLP) analysis. However, the terminal-restriction fragment (T-RF) 208 bp, which may belong to Lachnospiraceae, was stimulated by the chicory feed (P=0.03), and T-RF 370 bp that matches Enterobacter belonging to the Enterobacteria was reduced (P=0.004). Additionally, chicory increased the level of Bifidobacteria (P=0.001) and the faecal Campylobacter excretion level was transitorily reduced in chicory-fed piglets at 7 weeks of age (P=0.029). Unfortunately, it was not possible to assess the effect of chicory on post-weaning diarrhoea as it did not develop. In conclusion, feeding piglets chicory around the time of weaning caused complex changes of the microbiota and parasite communities within the intestinal tract, and feeding piglets chicory may therefore serve as an animal-friendly strategy to control pathogens

Ground state order and spin-lattice coupling in tetrahedral spin systems Cu2Te2O5X2

High-resolution ac susceptibility and thermal conductivity measurement on Cu2Te2O5X2(X=Br,Cl) single crystals are reported. For Br-sample, sample dependence prevents to distinguish between possibilities of magnetically ordered and spin-singlet ground states. In Cl-sample a three-dimensional transition at 18.5 K is accompanied by almost isotropic behavior of susceptibility and almost switching behavior of thermal conductivity. Thermal conductivity studies suggest the presence of a tremendous spin-lattice coupling characterizing Cl- but not Br-sample. Below the transition Cl-sample is in a complex magnetic state involving AF order but also the elements consistent with the presence of a gap in the excitation spectrum.Comment: version accepted for publication in Phys.Rev.B-Rapid Communicatio

On two-dimensionalization of three-dimensional turbulence in shell models

Applying a modified version of the Gledzer-Ohkitani-Yamada (GOY) shell model, the signatures of so-called two-dimensionalization effect of three-dimensional incompressible, homogeneous, isotropic fully developed unforced turbulence have been studied and reproduced. Within the framework of shell models we have obtained the following results: (i) progressive steepening of the energy spectrum with increased strength of the rotation, and, (ii) depletion in the energy flux of the forward forward cascade, sometimes leading to an inverse cascade. The presence of extended self-similarity and self-similar PDFs for longitudinal velocity differences are also presented for the rotating 3D turbulence case