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Bone graft in bilateral mandibular sagittal split osteotomy: the current state of practice in France
No full textInternational audienceIntroductionBilateral sagittal split osteotomy of the mandible (BSSO) is the most common orthognathic surgery procedure. The use of bone grafting seems widely used whereas its interest has not been shown to date. The aim of this study was to describe the current state of practice of bone graft in BSSO in France.Materials and methodsAn online survey was used to collect data about the use of bone grafting in BSSO procedures among French maxillofacial surgeons.ResultsOne hundred and forty-eight surgeons responded to the survey, mostly maxillo-facial surgeons (96 %). Only 31.8 % of participants had already performed grafts in BSSO and the majority did it in less than 10 % of cases. The main grafting indication was the degree of advancement especially for advances over 10 mm. Different types of grafts were used, mainly: autologous bone grafting (mandibular or hip) or other bone grafting (xenograft, allograft).ConclusionThis survey shows the diversity of practices in France regarding the use of grafting in BSSO. Further studies are needed to investigate prospectively the utility of such procedures
Bioactive dextran-based scaffolds from emulsion templates co-stabilized by poly(lactic-co-glycolic acid) nanocarriers
No full textInternational audiencePorous polymer scaffolds are widely investigated as temporary implants in regenerative medicine to repair damaged tissues. While biocompatibility, degradability, mechanical properties comparable to the native tissues and controlled porosity are prerequisite for these scaffolds, their loading with pharmaceutical or biological active ingredients such as growth factors, in particular proteins, opens up new perspective for tissue engineering applications. This implies the development of scaffold loading strategies that minimize the risk of protein denaturation and allow to control their release profile. This work reports on a straightforward method for preparing bioactive dextran-based scaffolds from high internal phase emulsion (HIPE) templates containing poly(lactic-coglycolic acid) (PLGA) nanoparticles (NPs) serving both as co-stabilizers for the emulsion and nanocarriers for drug or therapeutic protein models. Scaffold synthesis are achieved by photocuring of methacrylated dextran located in the external phase of a HIPE stabilized by the NPs in combination or not with a non-ionic surfactant. Fluorescent labelling of the NPs highlights their integration in the scaffold. The introduction of NPs, and even more so when combined with a surfactant, increases the stability and mechanical properties of the scaffolds. Cell viability tests demonstrate the non-toxic nature of these NPs-loaded scaffolds. The study of the release of a model protein from the scaffold, namely lysozyme, shows that its encapsulation in nanoparticles decreases the release rate and provides additional control over the release profile
Uterine organoids as in vitro model sights into post-mating endometritis characterisation in mares
No full textInternational audienceEndometritis is a major cause of subfertility in mares and a significant concern for the equine breeding industry. Susceptible mares fail to effectively resolve physiological post-breeding inflammation, resulting in persistent endometritis, intrauterine fluid accumulation and decreased fertility. Although progress has been made in understanding disease mechanisms, therapeutic options remain limited, especially given increasing restrictions on antibiotic use. This study aims to characterise and evaluate equine endometrial organoids derived from frozen biopsies of mares classified as susceptible (n = 5) or resistant (n = 5) to post-breeding induced endometritis (PBIE), based on reproductive history. Biopsies were collected during estrus, confirmed by transrectal ultrasonography (follicle ≥ 35 mm, uterine edema). Organoids were generatedusing established protocols and analysed histologically and ultrastructurally. Organoids were successfully from both phenotypes. Hematoxylin and eosin staining showed that the organoids reproduce the glandular morphology of native endometrial tissue. Transmission electron microscopy revealed polarised, ciliated epithelial cells forming tubular structures with distinct apical and basal orientation. Furthermore, 3Dlight-sheet fluorescence microscopy confirmed the phenotypic resemblance of whole organoids to native endometrial glands. These findings highlight the potential of equine endometrial organoids as a physiologically relevant in vitro model for reproductive research and innovation. Differences between susceptible and resistant could subjectively be seen, RNAseq results will be more objective. Cellular and molecular characterisation of organoid response to lipopolysaccharide challenge is pendin
Modeling the composition of syngas produced from pyrolysis and gasification of biomasses from various origins
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Evaluation de l'application des règles de biosécurité dans les cliniques canines en France et création de fiches synthétiques de mise en place et respect des bonnes pratiques d’hygiène
No full textLa biosécurité est une discipline encore émergente dans la pratique quotidienne de la médecine des animaux de compagnie, bien que les conséquences des infections nosocomiales et zoonotiques soient connues et reportées. L’objectif de ce travail était de réaliser un questionnaire à transmettre aux cliniques vétérinaires des petits animaux de compagnie en France, afin d’évaluer l’application des pratiques de biosécurité dans ces structures et de mettre en évidence les points forts ou lacunes généralement retrouvés, dans le but de créer des fiches synthétiques d’aide à l’application et l’amélioration des bonnes pratiques d’hygiène dans ces structures. Les résultats de notre étude ont montré que les notions de bases étaient présentes mais qu’il existe encore trop d’erreurs et d’oublis empêchant la bonne réalisation et l’efficacité des bonnes pratiques de biosécurité. La rédaction d’un protocole de biosécurité adapté à la clinique, et la désignation d’un membre du personnel responsable de la mise en place et du contrôle du respect de ces pratiques sont notamment absentes dans la majorité des cliniques enquêtées. Ainsi il était pertinent de rédiger des fiches synthétiques, à l’aide de ressources bibliographiques, permettant de donner des conseils d’application, de respect et de contrôle des différents volets de la biosécurité au sein d’une clinique vétérinaire. En plus de cet aspect pratique, ces fiches pourraient être utilisées pour construire une grille d’audit spécifique à chaque structure. Comme le suggère la diversité des réponses obtenues dans cette thèse, cela permettrait d’adapter les actions à mener à chaque clinique et à chaque pratique
Flagellin aerosol administration improves the efficacy of antibiotic treatment in Actinobacillus pleuropneumoniae infected pigs
No full textInternational audienceAbstract Swine infections with Actinobacillus pleuropneumoniae ( App ), the causative agent of porcine pleuropneumonia, lead to significant production losses. Surviving pigs may harbor antibiotic-resistant bacteria, highlighting the need for alternatives to reduce antimicrobial use. Stimulation of respiratory innate immunity via Toll-like receptor 5 (TLR5) agonists such as FLAMOD (a recombinant flagellin), has emerged as a promising strategy for combating bacterial lung infections. In a recent study, aerosolized administration of FLAMOD was found to elicit respiratory immune responses in pigs. This study assessed FLAMOD’s protective effects against App , either as a prophylactic intervention or as an adjunct to antibiotic therapy. Prophylactic administration of aerosolized FLAMOD via nebulization before App challenge failed to confer protection. However, in a therapeutic setting, where pigs were infected with App and treated with either a subtherapeutic dose of penicillin G (PenG) alone or a combination of PenG and aerosolized FLAMOD. Notably, the FLAMOD and PenG combination significantly improved bacterial clearance from the lungs. Moreover, FLAMOD-PenG treated pigs exhibited a trend toward increased weight gain and fewer lung lesions compared to those receiving PenG alone. These findings provide proof for the concept that FLAMOD enhances antibiotic efficacy, potentially lowering the required antibiotic dose and contributing to antimicrobial resistance mitigation in pigs
Étude du liquide et de la membrane synoviale chez les chevaux atteints de synovites inflammatoires et septiques
No full textSynovitis represents a common joint disorder in horses, often affecting performance and welfare. Accurate distinction between septic and non-septic forms remains essential for timely intervention. Arthroscopic and histological evaluations are valuable tools to assess synovial inflammation, while the role of cytokines in equine joint disease is gaining attention. However, few studies have explored their involvement in septic synovitis. This prospective study involved 70 horses divided into three groups: elective arthroscopy for non-septic joint lesions (n = 26), confirmed septic synovitis requiring lavage (n = 25), and periarticular injuries without synovial involvement (n = 19). Synovial fluid samples were collected for cytology, protein content, neutrophil percentage, and cytokine analysis using a MILLIPLEX® panel. Arthroscopic and histological scores were assigned to groups 1 and 2. Septic cases showed significantly higher cellularity, arthroscopic (mean: 8/12 vs 6/12; p = 0.004) and histological scores (mean: 9/15 vs 5.6/15; p = 0.006), and elevated concentrations of IL-1β, IL-6, TNF-α and IL-10. These cytokines showed positive correlations with both scoring systems and cytological parameters. This study highlights the diagnostic value of a combined clinical, arthroscopic, histological, and molecular approach in equine synovitis. IL-1β, IL-6, TNF-α and IL-10 may serve as useful biomarkers in distinguishing septic from non-septic cases.Les synovites septiques et non septiques représentent des affections articulaires fréquentes chez le cheval. Une étude prospective a été menée sur 70 équidés répartis en trois groupes : synovites non septiques (n = 26), synovites septiques confirmées (n = 25) et lésions péri-articulaires sans atteinte synoviale (n = 19). Une synoviocentèse a été réalisée chez tous les chevaux, et pour les groupes 1 et 2 associée à un examen arthroscopique avec une biopsie de la membrane synoviale. Les analyses ont porté sur la cellularité et la quantification de 23 cytokines à l’aide d’un panel MILLIPLEX® sur le liquide synovial et un score arthroscopique (0–12) de l’articulation synoviale ainsi qu’un score histologique (0–15) de la membrane synoviale attribués selon des grilles standardisées. Les résultats montrent une augmentation significative dans le groupe septique de la cellularité, des scores arthroscopiques (moyenne G2 : 8/12 ; G1 : 6/12 ; p = 0,004) et histologiques (moyenne G2 : 9/15; G1 : 5,6/15 ; p = 0,006). Les concentrations d’IL-1β, IL-6, TNF-α et IL-10 sont également plus élevées dans ce groupe. Des corrélations positives ont été mises en évidence entre ces cytokines, les scores et les paramètres cytologiques. Ces résultats soulignent l’intérêt d’une approche multimodale pour évaluer l’inflammation synoviale et identifient un panel de cytokines potentiellement discriminant dans les formes septiques
Individual or collective treatments: how to target antimicrobial use to limit the spread of Mannheimia haemolytica among beef cattle?
No full textInternational audienceThe overuse of antibiotics has become a major global concern due to its role in diminishing treatment effectiveness and positively selecting antibiotic-resistant bacterial strains. This issue is particularly important in the beef cattle sector, where Bovine Respiratory Diseases (BRD) impose significant economic and welfare burdens. BRD are complex, multifactorial conditions primarily affecting young calves and feedlot cattle, caused by a combination of viral and bacterial pathogens, environmental factors, and stressors. Despite efforts to reduce antimicrobial use (AMU), the cattle production system remains heavily reliant on antibiotics to control BRD, often through the implementation of collective treatments to prevent outbreaks. This study aimed at evaluating the impact of various strategies of collective treatments with antimicrobials on the spread of a BRD pathogen, Mannheimia haemolytica , specifically focusing on criteria for implementing collective treatments. Using a mechanistic stochastic model, we simulated the spread of M. haemolytica in a multi-pen fattening operation under sixteen different scenarios, considering pen composition, individual risk levels, and treatment strategies. Our findings suggest that an alternative criterion for collective treatments based on the speed of the disease spread, could reduce BRD incidence and AMU more effectively than conventional methods. This research highlights the importance of responsible collective treatment strategies and the potential benefits of novel criteria for collective treatment in improving animal health. Moreover, it emphasizes the need for transparency on the exposure to risk factors along the production chain
Étude retrospective des dynamiques professionnelles des vétérinaires diplômés de l'école vétérinaire de Nantes ONIRIS entre 2001 et 2020
No full textThis thesis offers a retrospective analysis of the career paths of veterinarians who graduated from the veterinary school of Nantes – Oniris – over the period 2001–2020. In a context of profound changes within the veterinary profession—marked by increasing feminization, diversification of practice models, and the emergence of new professional and societal challenges—this research aims to characterize post-graduation trajectories and identify the factors influencing their evolution. The study is based on a survey of 656 alumni, incorporating both quantitative and qualitative data on initial career plans, practice sectors and employment statuses, geographic mobility, and professional retraining. The analysis highlights significant heterogeneity in career paths, often characterized by frequent changes in sector, status, or location, frequently driven by considerations of well-being, quality of life, or professional dissatisfaction. Among the key findings, gender appears to play a significant role in career choices and persistence in certain fields (notably rural practice). The study also reveals a notable rate of career changes, including transitions outside the veterinary profession, and underscores structural vulnerabilities such as the lack of attractiveness of certain regions or sectors. This research underlines the need for a thorough reflection on the support provided to young veterinarians, the value of diverse practice models, and the prevention of professional distress. It provides useful insights for educational institutions, professional stakeholders, and public policymakers engaged in adapting the veterinary system to contemporary challenges.Cette thèse propose une analyse rétrospective des trajectoires professionnelles des vétérinaires diplômés de l’école vétérinaire de Nantes – Oniris – sur la période 2001-2020. Dans un contexte de profondes mutations de la profession vétérinaire, marqué par la féminisation, la diversification des modes d’exercice et l’émergence de nouveaux enjeux professionnels et sociétaux, cette recherche vise à caractériser les parcours post-diplôme et à identifier les facteurs influençant leur évolution. L’étude s’appuie sur une enquête menée auprès de 656 anciens étudiants, incluant des données quantitatives et qualitatives sur les projets initiaux, les secteurs et statuts d’exercice, les mobilités géographiques, ainsi que les reconversions professionnelles. L’analyse met en évidence une grande hétérogénéité des parcours, marqués par des changements fréquents de secteur, de statut ou de localisation, souvent motivés par des considérations de bien-être, de qualité de vie ou d’insatisfaction professionnelle. Parmi les résultats saillants, l’impact du genre apparaît significatif, tant dans les choix d’orientation que dans la persistance dans certaines disciplines (notamment la pratique rurale). L’étude révèle également un taux non négligeable de reconversions, y compris en dehors de la profession, et met en lumière des fragilités structurelles telles que le manque d’attractivité de certains territoires ou secteurs. Cette recherche souligne la nécessité d’une réflexion approfondie sur l’accompagnement des jeunes vétérinaires, la valorisation des divers modes d’exercice et la prévention du mal-être professionnel. Elle constitue un éclairage utile pour les institutions de formation, les acteurs de la profession, et les décideurs publics engagés dans l’adaptation du système vétérinaire aux enjeux contemporains
Sequence-based GWAS identify genomic regions associated with resistance to gastrointestinal strongyles in Holstein heifers
No full textInternational audienceGastrointestinal strongyles (GIS) are a raising concern for cattle health and productivity due to increasing resistance to anthelmintics and their ecological impacts. Enhancing genetic resistance represents a sustainable strategy to mitigate parasite burdens. As part of the GIVERNI project, we conducted a sequence level genome-wide association study (GWAS) to identify genomic regions associated with GIS resistance. A total of 1,736 Holstein heifers were genotyped using a 50K SNP array and phenotyped after their first grazing season. Four resistance traits were analyzed: serum immunoglobulin G Elisa test (IgG), Ostertagia oocysts count per gram of feces (OPG), log-transformed OPG, and serum pepsinogen levels (Pepsi). The 50k genotypes were imputed to whole-genome sequence using Run 9 of the 1000 Bull Genomes Project. GWAS were performed using a linear mixed model, with performance data adjusted for non-genetic effects. Heritabilities ranged from 0.07 (OPG) to 0.30 (Pepsi). Several significant QTLs were detected, highlighting candidate genes involved in immune response and gastrointestinal function. A major association was identified for IgG in a region implicated in enteric nervous system development. For OPG, a key signal appeared within an area involved in extracellular matrix composition, while Pepsi was associated with a region that plays a crucial role in gastric mucosal integrity. Post-GWAS analyses are ongoing to refine candidate genes. These findings advance knowledge on parasite resistance genetics and support genomic selection for resilient cattle. The GIVERNI project is funded by APIS-GENE