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International audience; Isolation and identification of Taylorella equigenitalis, the causative agent of contagious equine metritis, by bacteriology is laborious and does not permit differentiation from the other member of the genus, Taylorella asinigenitalis. Moreover, other organisms such as Klebsiella pneumoniae and Pseudomonas aeruginosa can also cause endometritis in mares and warrant diagnostic detection. Our objectives were to develop a rapid preparation method for field swab samples and to validate this protocol using new multiplex real-time polymerase chain reaction (rtPCR) detection tools for identification of these four pathogens. The complete analytical process from sample preparation to PCR analysis was then evaluated against bacteriology, the World Organisation for Health's (OIE) gold standard method for T. equigenitalis and commonly used for the other three pathogens. The diagnostic sensitivity and specificity of this method, which used direct lysis and a multiplex rtPCR, were 100% and >92%, respectively. This study provided a simple-to-use method for prebreeding screening of mares and stallions.

Un centre social “entend être un foyer d’initiatives porté par des habitants associés, appuyés par des professionnels capables de définir et de mettre en oeuvre un projet de développement social pour l’ensemble de la population d’un territoire” (FCSF; 2012). Leur mode de gouvernance, basé sur un principe de démocratie participative, permet à des habitants de participer à différents niveaux (bénévolat; gouvernance; réflexion de projets, activités…). Les aînés sont donc, en principe, dans une position de construction de leur participation (action construites par, pour et avec eux). Le contexte actuel de vieillissement démographique interroge les acteurs des CSX sur la participation sociale des aînés. De plus, la diversité des modes de gestion des structures (associations , collectivités) et des territoires les rendent peu lisibles auprès des acteurs qui accompagnent l’avancée en âge.Ce contexte demande à réinterroger les pratiques professionnelles et les besoins de ce public. Dans l’idée d’obtenir un regard distancié sur ces nouveaux enjeux et les modes de réponses qu’ils proposent, l’Union Régionale des centres sociaux et socioculturels des Pays de la Loire a débuté, depuis 2016, le projet I-CARE. Ce projet qui associe acteurs des CSX et doctorantes en géographie et sociologie, vise, entre autres, à identifier les formes de participations sociales des aînés dans les CSX et leurs impacts sur les personnes, les pratiques et les territoires. Nous proposons d’interroger la participation sociale des aînés dans les CSX, à partir d'un regard croisant et associant professionnels de terrain et chercheurs. Il s’agira de présenter des actions proposées par les CSX pour faire participer les aînés tout en abordant les enjeux que recouvre cette démarche, pour les publics concernés et les professionnels.Puis, à partir d'un regard interdisciplinaire mêlant sociologie et géographie, les "retombées" de ces actions sur les problématiques de l'avancée en âge.

Q fever is a worldwide zoonosis caused by Coxiella burnetii . Domestic ruminants are considered to be the main reservoir. Sheep, in particular, may frequently cause outbreaks in humans. Because within-flock circulation data are essential to implementing optimal management strategies, we performed a follow-up study of a naturally infected flock of dairy sheep. We aimed to (i) describe C. burnetii shedding dynamics by sampling vaginal mucus, feces, and milk, (ii) assess circulating strain diversity, and (iii) quantify barn environmental contamination. For 8 months, we sampled vaginal mucus and feces every 3 weeks from aborting and nonaborting ewes ( n = 11 and n = 26, respectively); for lactating females, milk was obtained as well. We also sampled vaginal mucus from nine ewe lambs. Dust and air samples were collected every 3 and 6 weeks, respectively. All samples were screened using real-time PCR, and strongly positive samples were further analyzed using quantitative PCR. Vaginal and fecal samples with sufficient bacterial burdens were then genotyped by multiple-locus variable-number tandem-repeat analysis (MLVA) using 17 markers. C. burnetii burdens were higher in vaginal mucus and feces than in milk, and they peaked in the first 3 weeks postabortion or postpartum. Primiparous females and aborting females tended to shed C. burnetii longer and have higher bacterial burdens than nonaborting and multiparous females. Six genotype clusters were identified; they were independent of abortion status, and within-individual genotype diversity was observed. C. burnetii was also detected in air and dust samples. Further studies should determine whether the within-flock circulation dynamics observed here are generalizable.

National audience; La fièvre Q est une zoonose causée par Coxiella burnetii. Les ruminants domestiques sont le principal réservoir. Les ovins en particulier, sont fréquemment associés à des épidémies humaines. Nous avons donc réalisé une étude en troupeau ovin afin d'évaluer la dynamique d'excrétion individuelle, la diversité génotypique et les contaminations environnementales. Pendant 8 mois, nous avons prélevé du mucus vaginal, des fèces, du lait, des poussières toutes les 3 semaines et de l'air toutes les 6 semaines. Les échantillons ont été analysés par PCR non-quantitative, puis pour les positifs par PCR quantitative. Les échantillons vaginaux et fécaux fortement positifs ont été génotypés par MLVA. Les niveaux d'excrétion étaient plus élevés dans le mucus et les fèces que dans le lait. Différents profils d'excrétion ont été observés selon la parité et le statut abortif. Six groupes génotypiques ont été identifiés. C. burnetii a été détectée dans l'air et les poussières.

International audience

International audience

International audience; To study the possible role of disease in the decline of endangered European mink (Mustela lutreola), we conducted a survey of antibody prevalence and renal carriage of pathogenic leptospira (Leptospira interrogans sensu lato) using serum and kidney samples collected from 1990 to 2007 from several free-ranging small carnivores and farmed American mink (Mustela vison) in southwestern France. An indirect microscopic agglutination test using a panel of 16 serovars belonging to 6 serogroups (Australis, Autumnalis, Icterohaemorrhagiae, Grippotyphosa, Panama, Sejroe) revealed antibodies in all species, with significant differences in antibody prevalences: 74% in European mink (n=99), 65.4% in European polecats (Mustela putorius, n=133), 86% in American mink (n=74), 89% in stone martens (Martes foina, n=19), 74% in pine martens (Martes martes, n=19), 35% in corn moo genets (Genetta genetta, n=79), and 31.% in farmed American mink (n=51). Serogroups Australis and Icterohaemorragiae were dominant in most free-ranging species; serogroup Grippotyphosa had high prevalences in European mink. Such high antibody prevalences have never been reported. They are probably related to the large number of known reservoirs, rats (Rattus spp.), muskrat (Ondatra zibethicus), and coypu (Myocastor coypu), in the study area. The polymerase chain reaction test specific for pathogenic leptospiral DNA detected renal carriage in 23% of 34 European mink, 22% of 18 polecats, and 15% of 33 free-ranging American mink, with no significant differences. Renal carriage shows that mustelids may shed leptospira for short periods, but their epidemiologic role is probably limited. High antibody prevalences suggest that the disease is unlikely to be highly pathogenic for these species; however, chronic forms of the disease (abortions, renal lesions) could reduce the reproductive success or life span of infected animals. Further studies on the pathogenicity of leptospirosis in these populations are needed to measure its impact on the population dynamics of these rodent predators.

The shedding of Coxiella burnetii in bovine, caprine, and ovine milk was measured using PCR, in 3 herds for each species, the bulk tank milk samples of which were positive at the time of their selection. Milk samples of 95 cows, 120 goats, and 90 ewes were sampled over 16 wk, as was the bulk tank milk. The shedding of C. burnetii in vaginal mucus and feces was checked at the beginning of the experiment and 2 mo later. The clinical signs in the selected herds as well as the duration and the shedding routes differed among the 3 species. The cows were asymptomatic and shed C. burnetii almost exclusively in milk. In one of the caprine herds, abortions due to C. burnetii were reported. The goats excreted the bacteria mainly in milk. In contrast, the ewes, which came from flocks with abortions due to Q fever (C. burnetii infection), shed the bacteria mostly in feces and in vaginal mucus. This could explain why human outbreaks of Q fever are more often related to ovine flocks than to bovine herds. These excretions did not seem more frequent when the samples were taken close to parturition. The samples were taken from 0 to 421 d after parturition in bovine herds and from 5 to 119 d and 11 to 238 d after parturition in the caprine and ovine herds, respectively. The shedding in milk was sometimes intermittent, and several animals shed the bacteria but were negative by ELISA: 80% of the ewes were seronegative, underscoring the lack of sensitivity of the ELISA tests available for veterinary diagnosis. The detection of antibodies in milk seems more sensitive than it is in serum.

This work aims to determine the energy cost of the conversion of L-methionine precursors (i.e., D-Met, D- and L-HMTBA) to L-Met. A framework representing the major biochemical pathways of nutrient metabolism was developed by van Milgen (2002), allowing quantification of the energy efficiencies of different nutritional scenarios. Using the concepts developed in this model, the theoretical energy costs of the conversion of D-Met, D-HMTBA, and L-HMTBA to L-Met were calculated. These enzymatic conversions involve oxidases (D-AAOX and L-HAOX) or a dehydrogenase (D-HADH) and result in the formation of a common intermediate, α-keto-methylthio-butanoic acid (KMB). The conversion of D-Met to KMB also results in the release of the amine group (-NH2). The transamination of KMB to L-Met requires an amine group from another amino acid. If this amine group comes from protein given in excess of protein deposition, less energy will excreted as urea or as uric acid. The ME value of D-Met would be equal to that of L-Met because the amine group released in the production of KMB can be reused for its transamination to L-Met. Considering the gross energy values of D,L-Met, D,L-HMBTA, urea, and uric acid are respectively 3522, 3366, 635, and 1926 kJ/mol. For 1 mol of D,L -HMBTA, the excretion of 0.5 mol urea or 0.25 mol uric acid is avoided. Consequently, the ME-to-GE ratio for D,L-HMBTA is (3366 + 630 × 0.5)/3366 = 109% in mammals and (3366 + 1926 × 0.25)/3366 = 114% in birds.The energy efficiencies of using ME also differ for the enantiomers of L-Met. The oxidative conversion of D-Met and L-HMTBA to KMB leads to the formation of hydrogen peroxide. This H2O2 can be catabolized through the oxidation of reduced glutathione (GSH) to oxidized glutathione (GSSG). The reduction of GSSG back to GSH requires 1 NADPH, which is equivalent to 3 ATP. Because 74.2 kJ of glucose is required to synthesize 1 ATP, the NE-to-ME ratio (relative to that of L-Met) can be calculated as (3522 - 3 × 74.2)/3522 = 92% for D-Met and as ((3366 + 630 × 0.5) – 3 × 74.2)/(3366 + 630 × 0.5) = 94% for L-HMTBA. The conversion of D-HMTBA to KMB yields 1 NADH, which is equivalent to a savings of 3 ATP. The relative NE-to-ME ratio is therefore ((3366 + 630 × 0.5) + 3 × 74.2)/(3366 + 630 × 0.5) = 106% for D-HMTBA. Consequently the NE-to-ME ratios (relative to that L-Met) are 96% and 100% for D,L-Met and D,L-HMTBA, respectively. Summarizing, compared with the energy values of L-Met, D,L-Met has an ME value of 100% and an NE value of 96%. For D,L-HMTBA these values are 114% and 100% for ME and NE, respectively.