HAL ENVT (Ecole Nationale Vétérinaire de Toulouse)
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Detection and characterization of disturbances in the trajectory of production and behavioral data for dairy cows
No full textInternational audienceTechnologies available in precision breeding facilitate the continuous collection of zootechnical and behavioral data at an individual scale. Analysis of these data could help monitoring animal welfare and production. In order to determine if methodologies of data analysis can detect and classify disturbances linked to events referenced by animal keepers, a supervised approach using the smoothing functions B-splines (FDA R package) was compared to a non-supervised approach using a Gaussian kernel smoothing (UpDown package). The analyzed data were milk yield (MY), dry matter intake (DMI) and standing time (ST) automatically collected during the first four months of 40 dairy cows’ lactations. Moreover, with FDA, the disturbances characteristics were recorded: duration, maximum and minimum differences between smoothed curves (i.e., reference curve being more smoothed than disturbed curve), and intensity (i.e., difference between maximum and minimum). Event type (health (H), feeding (F), reproductive (R)) effect on these variables was tested using a linear mixed model. Detection of disturbances was more sensitive with FDA than UpDown (respectively, MY: 6 vs 3%; DMI: 8 vs 1%; ST: 7 vs 0%). The specificity was similar between these two methods for all variables (≃99%). The maximum difference of ST disturbances was higher for feeding events than health events (P = 0.01), while for DMI disturbances it washigher for feeding events than reproductive events (P = 0.02). The duration of MY or MSI disturbances was longer thanthat of ST, regardless event type (MY: 10 ± 5 days, MSI: 11 ± 6 days, ST: 7 ± 4 days, P < 0.001). The intensity of disturbance was more important for ST than MY or MSI, regardless event type (P < 0.001). Based on these results, the FDA method seems more appropriate to detect all kinds of disturbances than UpDown. However, it is necessary to refine the determination of parameters detection (threshold for selecting disturbances, degree of smoothing), as well as the choice of variables to be able to better classify the disturbances
[Editorial] : A Special Issue of <i>Mass Spectrometry Reviews</i> to Honor Professor Richard B. Cole
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Avian influenza overview September–November 2025
No full textInternational audienceBetween 6 September and 28 November 2025, 2,896 highly pathogenic avian influenza (HPAI) A(H5) virus detections were reported in domestic (442) and wild (2,454) birds in 29 countries in Europe. The magnitude and geographical extent of these detections were unprecedented for this time of the year, particularly in wild birds. Large numbers of waterfowl were affected by the disease, and mass mortality of common cranes was observed along their migratory routes in Europe. Given the high levels of virus circulation in wild birds and the resulting high environmental contamination, most HPAI outbreaks in domestic birds were primary, with indirect contact with wild birds being the most likely source of infection. Among poultry species, turkeys were proportionally the most affected, and HPAI outbreaks were once again reported in vaccinated ducks. A slight increase in HPAI virus detections in mammals was noted among foxes and domestic cats in Europe, consistent with the increase in detections in wild birds. Between 9 September and 28 November 2025, 19 cases of avian influenza virus infection in humans, including two deaths, were reported in four countries: Cambodia (three A(H5N1) cases, one death), China (14 A(H9N2) cases), Mexico (one A(H5N2) case), and United States of America (USA) (one fatal A(H5N5) case). All of the A(H5) human cases (n = 5/5) reported exposure to poultry or a poultry environment prior to detection or onset of illness. The current high level of avian influenza virus in bird populations increases the risk of human exposure to infected animals. Nevertheless, given the widespread circulation of avian influenza viruses in animal populations, human infections remain rare. No instances of human-to-human transmission were documented during the reporting period. The risk posed by avian A(H5N1) clade 2.3.4.4b influenza viruses currently circulating in Europe remains low for the general public in the European Union/European Economic Area and low-to-moderate for those occupationally or otherwise exposed to infected animals or contaminated environments.</div
Nucleoside binding by a surface lipoprotein governs conjugative ICE acquisition in mycoplasmas
No full textInternational audienceABSTRACT Integrative and conjugative elements (ICEs) are major mediators of horizontal gene transfer in bacteria. However, the role of recipient cells in their acquisition has received little attention. Using the ruminant pathogens Mycoplasma agalactiae and Mycoplasma bovis as minimal models, we combined genome-wide transposon mutagenesis with high-throughput mating assays to identify recipient factors required for ICE acquisition. The surface lipoprotein P48 emerged as the primary determinant of ICE uptake in both species. Structural and functional analyses revealed that P48 is the substrate-binding component of an ABC transporter with nucleoside-binding capacity. A single-point mutation that abolished nucleoside binding drastically reduced ICE acquisition, demonstrating that P48-mediated nucleoside recognition is essential for conjugative transfer. However, ICE uptake did not require nucleoside transport, as inactivation of the transporter permease blocked nucleoside analog toxicity but not ICE invasion. Loss of P48 also triggered transcriptional activation of vestigial ICE genes, suggesting that surface recognition affects the intracellular state of the recipient. Remarkably, ICE transfer from recipient-derived donors was unaffected by P48 loss, underscoring its acquisition-specific role. Together, these results reveal a previously unrecognized, surface-exposed recipient factor critical for efficient ICE transfer in mycoplasmas and identify nucleotide binding as a central function in conjugation. By demonstrating that recipient-encoded functions can directly control ICE dissemination, this work challenges the donor-centric paradigm of bacterial conjugation and suggests new strategies to restrict horizontal gene flow in pathogenic and synthetic mycoplasmas. IMPORTANCE Integrative and conjugative elements (ICEs) are mobile DNA elements that drive bacterial conjugation, a major process by which bacteria exchange genes. Although conjugation has been studied for decades, the focus has been almost exclusively on donor cells and the ICE itself, leaving the role of recipient cells largely overlooked. Using the wall-less ruminant pathogens Mycoplasma agalactiae and Mycoplasma bovis as minimal models, we discovered that a single recipient lipoprotein is required for efficient ICE uptake. Our data show that nucleoside recognition by P48, but not transport, is critical for conjugation, revealing an unexpected mechanistic link between nutrient sensing and gene acquisition. These findings shift the paradigm of conjugation from a donor-driven process to one jointly determined by donor and recipient functions. By identifying a recipient-encoded determinant of ICE transfer, this work opens new avenues to control horizontal gene flow in both pathogenic and engineered bacteria
The Diversity of Oligosaccharide Composition in Rabbit Milk and Its Association with the Development of the Cecal Microbiota and the Survival of Young Rabbits
No full textInternational audienceBackground: Milk oligosaccharides (MOs) are involved in microbiota development and health in newborns. Given the physiological immaturity of rabbits at birth, we hypothesized that MO profile diversity could explain the variability of survival and microbiota composition in young rabbits.Objective: Our aims were as follows 1) to characterize the MOs in rabbit, 2) to assess the variability in MO profiles over the course of lactation, 3) to evaluate associations with young rabbit survival, and 4) to explore links with cecal microbiota composition.Methods: MOs from 76 rabbit does were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Changes over lactation were evaluated in a subset of 10 does. Young rabbit survival data were recorded across 7 reproductive cycles in 67 does. Cecal microbiota composition was assessed in 20 young rabbits at 8 and 26 d and correlated with maternal MO profiles.Results: A total of 49 MOs were identified, with 3 (sialyllactose, Hex2_HexNAc1, and lacto-N-fucopentaose [LNFP]) found in all does. Sialylated MOs predominanted, with a large dominance of sialyllactose (median: 71% of relative abundance). However, 70% of the rabbit MOs were fucosylated. Over the course of lactation, sialyllactose relative abundance decreased, whereas LNFP increased (30% and 45% respectively at day 25 of lactation). MO profiles in the second lactation were weakly related to offspring survival over 7 breeding cycles. At 8 d of age, fucosyllactose positively correlated with Fusicatenibacter in suckling young rabbit cecal contents. At 26 d, the relative abundance of Oscillospiraceae NK4A214 group was positively associated with Hex4_HexNAc1_Fuc1, whereas Ruminococcus, Alistipes, and Coprococcus were negatively associated with sialyllacto-N-fucopentaose, Hex3_HexNAc2_Fuc1 and sialyllacto-N-tetraose, respectively.Conclusions: Rabbit MOs are variable among individuals and across lactation stages, with certain MOs linked to early microbiota composition of the offspring, highlighting their potential prebiotic role in neonatal development
Robust pan-junctional reinforcement preserves the gut epithelial barrier under mechanical stress
No full textEpithelia are specialized tissue barriers that safeguard the organism’s internal milieu from the hostile external environment, a function critically dependent on intercellular junctions. In the colon, this barrier is repeatedly challenged by mechanical distension from faeces and it is unknown whether and how the colon adapts to such stress, which could otherwise compromise barrier integrity. Here, we show that faeces-mediated mechanical distension triggers coordinated remodelling at cell- and tissue-scale, suggestive of mechanoadaptation. This response includes recruitment of junctional proteins at all three types of adhesive cell-cell junctions (tight junctions, adherens junctions and desmosomes). We identified two modes of recruitment: stable responders (ZO-1, E-cad, plakoglobin) with sustained junctional enrichment, and adaptive responders (desmoplakin, keratin 8) with progressive accumulation during distension. Distension was also accompanied by perijunctional recruitment and activation of non-muscle myosin II (NMMII). Through genetic, pharmacological, and mechanical perturbations, we demonstrated that NMMII activation is an early and critical step for mechanoadaptation. This process requires extracellular calcium influx, and Piezo1 activation is sufficient to trigger NMMII activation and junctional recruitment. Loss of NMMII function abrogated the junctional response to distension across all three junctional complexes, including desmosomes, resulting in disorganised junctions and barrier breach. Together, our findings uncover a robust physiological mechano-adaptive response of the adult colonic epithelium to an extrinsic mechanical stress, whereby coordinated reinforcement of all junctional complexes, controlled by myosin II and mechanosensitive calcium influx, plays an essential role in preserving intestinal barrier integrity
Description of the Toulouse GOLD Cohort : an open science study to better characterize the first days of life and their short, medium and long term consequences in dogs
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Relationship between hygiene practices in breeding catteries and kennels on gastrointestinal parasite infestation
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Objectifs du réseau RESPLANDIR et présentation des résultats de l’intercomparaison des plateformes d’irradiation à l’aide de la dosimétrie alanine
No full textInternational audienceRESPLANDIR (Réseau des Plateformes National d’Irradiation) est un réseau national qui regroupe différentes modalités d’irradiation (hadron et rayons X) pour la recherche en radiobiologie et la dosimétrie. Ses principaux objectifs sont de partager les compétences, d’échanger, de mutualiser et de développer des stratégies communes pour l’irradiation et la dosimétrie. Des journées thématiques et des sessions spécifiques lors des congrès de la SFBR (https://sfbr.fr/) ont été organisées afin de renforcer les échanges entre les différents membres du réseau. Dans le cadre de cette collaboration une intercomparaison a été initiée dans le but de réaliser une validation dosimétrique des installations d’irradiation du réseau à l’aide de la dosimétrie alanine. Pour cela des pastilles d’alanine ont été envoyées aux participants afin qu’elles soient irradiées suivant différentes modalités. Les irradiations ont concerné des installations produisant des rayons X (SARRP ou cabinet conventionnel) ainsi que des faisceaux de particules (protons (ligne de recherche ou centre hospitalier) et ions carbone). Pour les installations « Rayons X», nous avons choisi de mimer une irradiation in vivo chez la souris et de vérifier si la dose prescrite (calculée via un système de planification de traitement ou estimée expérimentalement) correspondait bien à la dose réellement mesurée. Pour cela, des pastilles d’alanine ont été placées dans l’abdomen de souris préalablement sacrifiées puis irradiées suivant différents types de traitements (un ou deux faisceaux) et tailles de champs (corps entier ou irradiation localisée). Pour les installations hadroniques, sur lesquelles il n’est pas forcément possible d’irradier des animaux, une configuration d’irradiation dans des puits de cellules a été choisie. Des irradiations avec des protons de différentes énergies (25 à 200 MeV) et des carbones ont pu être réalisées. L’objectif de ce travail est de présenter la méthodologie mise en œuvre pour cette validation dosimétrique ainsi que les résultats obtenus
Évaluation de la sensibilité au fluralaner d'une souche de Ctenocephalides felis résistante au fipronil
No full textCtenocephalides felis is the main ectoparasite of domestic carnivores and a vector of pathogens. Prevention relies on the use of insecticides, whose effectiveness could be threatened by the emergence of resistance. Fipronil acts on GABA and GluCl receptors, which are also targets of isoxazolines, raising the question of cross-resistance. This study compared the sensitivity of two strains of C. felis, one susceptible and one resistant to fipronil, to fluralaner, through ingestion and contact. Preliminary tests confirmed a high level of resistance in the fipronil-resistant strain, with a resistance ratio of 25. Regarding fluralaner, cross-resistance was demonstrated by ingestion, with a resistance ratio of 13, but not by contact. These results, which are unexpected considering the literature, require confirmation by further investigation.Ctenocephalides felis est le principal ectoparasite des carnivores domestiques et un vecteur d'agents pathogènes. La prévention repose sur l'usage d'insecticides, dont l'efficacité est menacée par l'émergence possible de résistances. Le fipronil agit sur les récepteurs GABA et GluCl, également ciblés par les isoxazolines, soulevant ainsi la question d'une éventuelle résistance croisée. Cette étude a comparé la sensibilité de deux souches de C. felis sensible et résistante au fipronil, au fluralaner, par ingestion et par contact. Les tests préliminaires ont confirmé un fort niveau de résistance de la souche résistante au fipronil, avec un rapport de résistance de 25. Concernant le fluralaner, une résistance croisée a été mise en évidence par ingestion, le rapport de résistance étant de 13, mais non par contact. Ces résultats, inattendus au regard de la littérature, nécessitent confirmation par des investigations complémentaires