Antibiotic resistance in veterinary medicine : impact on public health and animal health

Acquired antibiotic resistance is a source of therapeutic failure in both human and veterinary medicine. Long considered as a hospital problem, the development of antibiotic resistance in pathogenic bacteria responsible for community infection and of multi-drug resistant bacteria is considered as a major issue by public health authorities. From an ecological point of view, every use of antibiotic both in animals and in man worldwide promotes such resistances. It is important to monitor bacterial resistance as well as the use of antibiotics in veterinary medicine, to study the relations between treatment and resistance and promote responsible use by veterinarian prescribers. In daily practice, veterinarians must prescribe antibiotics in a rational way, based on sound epidemiological knowledge.La résistance acquise aux antibiotiques est une source d'échecs thérapeutiques en médecine humaine et vétérinaire. Longtemps considéré comme un problème hospitalier, le développement de la résistance chez des bactéries pathogènes responsables d'infection communautaire et l'apparition de bactéries multi-résistantes sont un sujet d'inquiétude majeur pour les instances sanitaires. D'un point de vue écologique, chaque utilisation d'antibiotique dans le monde entier, tant chez l'animal que chez l'homme, contribue au développement de cette résistance. Il est important de surveiller les résistances bactériennes ainsi que les modalités d'utilisation des antibiotiques en médecine vétérinaire, pour étudier les relations entre traitement et résistance, et promouvoir un usage responsable des prescripteurs vétérinaires. Dans sa pratique quotidienne, le vétérinaire doit raisonner sa prescription d'antibiotiques en fonction de sa connaissance épidémiologique

Multi-fluid approach for the numerical prediction of wall erosion in an elbow

Multiphase pipelineflows are widely used in the oil and gas industry to transport solid-liquid or gas-solid mix-tures. Erosion caused by the impact of solid particles is a major challenge for equipment maintenance and safety,especially in complex geometries such as elbows. In this work, a CFD study on wall erosion in a 90° standardelbow has been performed using a multi-fluid approach, also called Euler/Euler, for poly-dispersedfluid-particleflows. A model is used for the erosion prediction taking into account particle turbulent kinetic energy obtainedfrom the Euler-Euler approach. A good agreement with experiments is observed. The effects of wall roughnessand solid massflow rate on the erosion rate are also investigated. For a certain amount of sand passing throughthe pipe elbow, there exists a solid massflow rate for which the particle impact damage is most dramatic

Absence of superconductivity in ultra-thin layers of FeSe synthesized on a topological insulator

The structural and electronic properties of FeSe ultra-thin layers on Bi$_{2}$Se$_{3}$ have been investigated with a combination of scanning tunneling microscopy and spectroscopy and angle-resolved photoemission spectroscopy. The FeSe multi-layers, which are predominantly 3-5 monolayers (ML) thick, exhibit a hole pocket-like electron band at \bar{\Gamma} and a dumbbell-like feature at \bar{M}, similar to multi-layers of FeSe on SrTiO$_{3}$. Moreover, the topological state of the Bi2Se3 is preserved beneath the FeSe layer, as indicated by a heavily \it{n}-doped Dirac cone. Low temperature STS does not exhibit a superconducting gap for any investigated thickness down to a temperature of 5 K

Estimation of transmission parameters of a fluoroquinolone-resistant Escherichia coli strain between pigs in experimental conditions

Antimicrobial resistance is of primary importance regarding public and animal health issues. Persistence and spread of resistant strains within a population contribute to the maintenance of a reservoir and lead to treatment failure. An experimental trial was carried out to study the horizontal transmission of a fluoroquinolone-resistant Escherichia coli strain from inoculated to naïve pigs. All naïve contact pigs had positive counts of fluoroquinolone-resistant E. coli after only two days of contact. Moreover, re-infections of inoculated pigs caused by newly contaminated animals were suspected. A maximum likelihood method, based on a susceptible-infectious-susceptible (SIS) model, was used to determine the transmission parameters. Two transmission levels were identified depending on the quantity of bacteria shed by infected individuals: (i) low-shedders with bacterial counts of resistant E. coli in the faeces between 5*103 and 106 CFU/g (βL = 0.41 [0.27; 0.62]), (ii) high shedders with bacterial counts above 106 CFU/g (βH = 0.98 [0.59; 1.62]). Hence, transmission between animals could be pivotal in explaining the persistence of resistant bacteria within pig herds

Pharmacoepidemiologic approach of antibiotic use and its impact on antibiotic resistance

La pharmaco-épidémiologie, par l’application des méthodes et raisonnements épidémiologiques à l’usage des antibiotiques, permet d’appréhender leurs conditions d’utilisation dans la population et leurs effets induits tels que la résistance bactérienne. Par des études descriptives, il est possible de déterminer les quantités d’antibiotiques utilisées, les motifs d’utilisation et les acteurs de cette utilisation (vétérinaires, éleveurs...). Par des études analytiques, il est possible d’ étudier le lien existant entre utilisation des antibiotiques, conditions d’élevage et résistance bactérienne aux antibiotiques. Toutes ces études et les connaissances ainsi acquises doivent permettre de caractériser l’usage des antibiotiques en élevage et d’agir sur les pratiques si nécessaire, pour réduire notamment les risques de sélection et de diffusion de résistance. Ceci doit contribuer à la définition et à la promotion d’un usage raisonné des antibiotiques. Le présent article expose, au travers des actions mises en œuvre en France dans le cadre d’une convention DGAL-AFSSA, l’application de cette démarche pharmaco- épidémiologique à l’usage des antibiotiques en productions animales en France.Pharmaco-epidemiology deals with the quantities of drugs consumed and their effects on populations in terms of epidemiological concepts and tools. Applied to the animal production, descriptive studies provide important information about the amount of antibiotics that are consumed, how and for which purpose. Analytical studies are also carried out about what could be considered as a consequence of antibiotic consumption : bacterial antimicrobial resistance. Those studies are designed to assess the relationships between antibiotic consumption, rearing conditions and antibiotic-resistant bacterial carriage by animals. Therefore, pharmaco- epidemiological studies improve knowledge about antibiotic consumption and its consequences in term of bacterial resistance. By the way they contribute to the definition of a rational and prudent use of antibiotics in animal production

Monitoring programme of antimicrobial resistance in sentinel bacteria isolated from intestinalflora of pigs and poultry 1999-2001

Un programme de surveillance des taux de résistance aux antibiotiques chez des bactéries indicatrices ( Escherichia coli et Enterococcus faecium) isolées de la flore intestinale du poulet de chair et du porc a été mis en place, en France, pour déterminer leurs évolutions en fonction du temps. Plusieurs antibiotiques représentatifs des classes d’antibiotiques utilisées comme médicaments vétérinaires ou comme facteurs de croissance ont été étudiés. Une évolution statistiquement significative du niveau de résistance à trois antibiotiques a été mis en évidence chez les souches d’ Enterococcus faecium isolées chez le poulet de chair. L’hypothèse d’égalité des niveaux de résistance entre les différentes années d’études n’a pas pu être rejetée pour les souches d' Enterococcus faecium isolées chez le porc. Une réduction statistiquement significative de la résistance chez les souches d' Escherichia coli est observée pour la streptomycine et le triméthoprime pour celles isolées du poulet de chair et pour la streptomycine et l’apramycine pour celles isolées du porc.A monitoring programme of antimicrobial resistance of sentinel bacteria (Escherichia coli and Enterococcus faecium) isolated from intestinal flora of poultry and pigs has been implemented to follow trends in France. Several antimicrobials representative of different antimicrobial families used as veterinary drugs and feed additives has been tested. A statistically significant variation between the different years has been observed for Enterococcus faecium strains isolated from poultry for resistance against three antimicrobials while the hypothesis of equality could not be rejected for pig strains. A statistically significant decrease of Escherichia coli resistance was observed in each animal species for two antimicrobials tested (streptomycin and trimethoprim in poultry, streptomycin and apramycin in pig)

Occurrence of antibiotic residues in raw fish Clarias gariepinus and Oreochromis niloticus from intensive rearing system in Benin

International audienceAn observational cross-sectional study was carriedy out to investigate antibiotic residues in Clarias gariepinus and Oreochromis niloticus from the intensive rearing system in Southern Benin. The targeted antibiotic families were tetracyclins, amphenicols, beta-lactams and macrolides. One hundred and forty-four (144) samples were used per antibiotic family for residue detection in the fish muscle, making 576 treated samples. The Charm II method based on radioimmunoassay was used. The results showed an overall residue prevalence of 11.1%, which is attributable to tetracyclines alone. There was no residue of the other antibiotic families in the treated fish muscles. The adult fish were the only contaminated age group with 22.2% residue prevalence compared to the fingerlings (p < 0.05). Likewise, the antibiotic residues were significantly (p< 0.05) more prevalent in Clarias gariepinus (16.7%) than in Oreochromis niloticus (5.6%). The adult fishes are generally fattier than the young ones, and that can lower the fish body antibiotic elimination capability. This first detection of tetracyclines residues in fish produced in Benin shows the need to rule and control antibiotic use in the developing fish industry to preserve consumers' health

Structure of the French farm-to-table surveillance system for Salmonella

The French surveillance system for Salmonella is based on a national system which can be traced back to 1947 for human cases and to the late 1980s for the main animal reservoirs. This system has evolved with regard to both European regulations and changes in the observed prevalence of Salmonella. European regulations establish a solid foundation on which to build an active harmonised surveillance system at the production level and for integrating data from the whole food chain. There are also passive surveillance networks in the agri-food and veterinary sectors and these allow complementary information to be obtained from other sectors or sources. The main strengths and weaknesses of these systems are described and a comparison of the different approaches is presented using a grid analysis. The results show that passive systems are very useful for detecting emerging or unusual events and for early warning of outbreaks. They also produce time series of cases or can determine the number of strains that should be used to assess the impact of interventions. Active surveillance data, due to their representativeness and reliability, are key elements in the application of risk analysis tools such as quantitative risk assessment or attribution. Thus, although data is collected and analysed by various organisations, these organisations all collaborate at a national level. Furthermore, their implication in European and international projects is effective and the main objectives of a surveillance system can be met

Mechanical Properties of Hip Capsule Tissue After a Hip Arthroplasty

Total hip arthroplasty is a surgical procedure that replaces the hip joint by artificial materials. Here, the morphological and mechanical properties of the scar tissues that form around implants composed of either polymer and metal or ceramic are compared to native tissue removed during an initial total hip arthroplasty. Immuno-histological analyses of the samples showed different hierarchical structures of the tissues over three scales: the fiber, the fascicle and the tissue scales. At the tissue scale, micro-tensile tests were performed on millimetric samples and their non-linear elastic responses were identified by either an exponential law or an Ogden third-order constitutive model. At the fiber scale, a patient-specific micro-scale finite element model including the measured morphological parameters and the identified Ogden constitutive models for the fiber and for the matrix composed of a mixture of fibers in ground substance

Etude des déplétions tissulaires du monensin chez le poulet et la dinde

Etude des déplétions tissulaires du monensin chez le poulet et la dinde. 8. Journées de la Recherche Avicol