HAL ENVT (Ecole Nationale Vétérinaire de Toulouse)
Not a member yet
16577 research outputs found
Sort by
Mycotoxins in oilseeds and vegetable edible oils: an overview of toxicity, occurrence and exposure
No full textInternational audienceOilseeds and vegetable oils, essential components of the human diet, can be contaminated by various mycotoxins, fungal toxic secondary metabolites. This review presents an overview of (i) the chronic toxicity of mycotoxins, (ii) their occurrence in vegetable oils and oilseeds and (iii) consumer exposure through these foodstuffs. A systematic search was performed to identify reviews, published during the last 10 years, concerning the occurrence of mycotoxins in commonly consumed oils and oilseeds. Around fifteen different mycotoxins were detected, the most common being the regulated mycotoxins: aflatoxins, ochratoxin A, zearalenone, fumonisins and trichothecenes. Emerging mycotoxins such as Alternaria toxins, beauvericin and cyclopiazonic acid were also detected. These toxins have various effects and target multiple organs (kidneys, liver, nervous system, digestive system, etc.) and some of them, such as aflatoxin B1, ochratoxin A and fumonisins, are carcinogenic or possibly carcinogenic to humans. Mycotoxins in oils and oilseeds are sometimes present in quantities exceeding European standards for consumer safety. Although they are consumed in smaller quantities than other food groups (e.g., cereals), the contribution of edible oils to the chronic dietary exposure to various mycotoxins should not be neglected. In the case of certain mycotoxins, such as alternariol monomethyl ether, vegetable oils even account for a significant proportion (around 40%) of average chronic European dietary exposure.Les graines oléagineuses et les huiles végétales, éléments essentiels de l’alimentation humaine, peuvent être contaminées par diverses mycotoxines, métabolites secondaires toxiques produits par des champignons. Cette revue présente (i) une vue d’ensemble de la toxicité des mycotoxines, (ii) de leur présence dans les huiles végétales et les graines oléagineuses et (iii) de l’exposition des consommateurs par le biais de ces denrées alimentaires. Une recherche systématique a été effectuée pour recenser les publications parues au cours des dix dernières années concernant la présence de mycotoxines dans les huiles et les graines oléagineuses couramment consommées. Une quinzaine de mycotoxines différentes ont été identifiées dans les huiles et les graines oléagineuses les plus couramment utilisées, les plus courantes étant les mycotoxines réglementées : aflatoxines, ochratoxine A, zéaralénone, fumonisines et trichothécènes. Des mycotoxines émergentes telles que les toxines d’ Alternaria , la beauvéricine et l’acide cyclopiazonique ont également été détectées. Ces toxines ont des effets toxiques variés ciblant plusieurs organes (les reins, le foie, le système nerveux ou le système digestif). L’aflatoxine B1, l’ochratoxine A et les fumonisines, en particulier, sont considérées comme cancérogènes ou possiblement cancérogènes pour l’homme. Les mycotoxines sont parfois présentes dans les huiles et les graines oléagineuses à des niveaux parfois supérieurs aux limites fixées par la réglementation européenne pour la sécurité des consommateurs. Bien qu’elles soient consommées en plus faibles quantités que d’autres aliments tels que les céréales, la contribution des huiles alimentaires à l’exposition alimentaire chronique aux différentes mycotoxines mérite une attention particulière. Dans le cas de certaines mycotoxines, comme l’alternariol monomethyl ether, les huiles végétales représentent même une part significative (environ 40 %) de l’exposition alimentaire chronique moyenne en Europe
Plastics used in agriculture and for food: uses, properties and impacts. Condensed report of the collective scientific assessment
No full textStudy of genetic progress in the context of disconnection between two originally connected populations
No full textInternational audienceGenetic progress of breeding programs is highly dependent on the size of reference populations and the relatedness between reference populations and selection candidates. Many reasons can lead a population to split into several subpopulations (sanitary, physiological, political reasons, etc.). More specifically, alternative (e.g., organic) farming may lead to farms breaking away from the conventional scheme to form a distinct breeding scheme, especially in organic sheep farming where the ban on hormones makes the use of artificial insemination (AI) difficult. However, these potential splits of the population into several smaller subpopulations could decrease genetic progress. The aim of our study was to investigate, using stochastic simulations, the impact of separation of the population into two subpopulations while still applying the same breeding objective and methods. We simulated a breeding program inspired by a dairy program but applicable to different species. We simulated two different initial population sizes with 5400 (10,800) females mated to 90 (180) males and a trait of heritability 0.30. This population was under selection for several discrete generations (G-9 to G-1) as a single population. Then, for the last 11 cycles of selection, the population was either maintained as a unique population (scenario "NoSep", which was the reference scenario) or split into two subpopulations with different ratios: 50/50, 60/40, 70/30, 80/20, and 90/10. We studied three scenarios in which the population was split: CE (separation and Common Evaluation), in which the evaluation remained common between both subpopulations; SE (separation and separate evaluation), in which the subpopulations were evaluated individually; and NoSel (Separation and No Selection), in which the breeding males were randomly selected, as opposed to the two previous scenarios in which we selected the males based on their GEBVs. We studied the evolution of differentiation of populations (F-st), accuracy of predictions, genetic progress, and rate of inbreeding over generations. We observed a faster genetic divergence in the case of an unbalanced split and separate evaluation (F-st in G11 equal to 0.134 for the ratio 90/10 scenario SE). The separate evaluation had a significant, negative effect on both the accuracy and genetic gain of the smallest population (minimal accuracy of 0.53 and maximal loss of 16.6% for ratio 90/10 with 5400 females), whereas the accuracy and genetic gain of the largest population were not impacted. Combining the evaluations led to smaller but still significant deterioration of the genetic gain of the smallest population when the ratio was very unbalanced (loss of genetic gain of 14.3% for a ratio of 90/10 with 5400 females). In conclusion, population separation has a negative impact on genetic gain, particularly for small populations. Although it does help in alleviating divergence and loss of genetic gain, joint evaluation can not fully compensate for the split of the populations
Genetic and epigenetic selection signatures from pool sequencing experiment
No full textInternational audienc
Mast Cells Promote Inflammatory Th17 Cells and Impair Treg Cells Through an IL-1β and PGE2 Axis
No full textInternational audiencePurpose: CD4+ effector T cells (Teffs) play a key role in immune responses by infiltrating the sites of inflammation and modulating local leukocyte activity. In turn resident immune cells shape their response. This study aimed to investigate the influence of mast cells (MCs) on Teff biological responses. Methods: This study examined human MC-Teff interactions, focusing on how MCs shape Teff responses. Flow cytometry, qRT-PCR, and cytokine assays were used to analyze the impact of primary human MCs on the Teff phenotype and function. MC-Teff crosstalk within Crohn’s disease patient tissues was assessed using confocal microscopy and advanced image analysis. Results: MCs promoted the differentiation of Th17 cells, particularly the inflammatory Th17.1 subset, that secretes IFN-γ and GMCSF. This differentiation was driven by the PGE2 and IL-1β axis. Additionally, MCs disrupted the phenotype and impaired the suppressive function of regulatory T cells (Tregs) through PGE2, skewing the Th17/Treg balance. The analysis of biopsies from patients with Crohn’s disease indicated that this MC/Teff crosstalk may play a role in the pathogenesis of auto-inflammatory processes. Conclusion: MCs influence CD4+ T cell responses by fostering pro-inflammatory Th17 differentiation while impairing Treg function. This interaction underpins a Th17/Treg imbalance, which is significant in auto-inflammatory diseases such as Crohn’s disease, positioning MCs as critical drivers of disease pathogenesis. Plain language summary: The immune system functions through complex interactions between different types of cells to protect the body from harm. CD4+ T cells are crucial in managing inflammation by directing other immune cells. Mast cells, found in tissues such as the skin and gut, are among the first to respond to potential threats and can influence T cell behavior. This study examined how mast cells and T cells interact in vitro, particularly in Crohn’s disease, a condition in which the immune system causes gut inflammation. We used laboratory techniques to study how mast cells affect T cells, examining their behavior and communication. We also studied tissue samples from individuals with Crohn’s to determine how these interactions occur in real life. We found that mast cells encourage the development of inflammatory T cells called Th17, particularly a type known as Th17.1, which produce strong inflammatory signals. This process relies on specific molecules such as PGE2 and IL-1β. Simultaneously, mast cells weaken the function of regulatory T cells (Tregs), which normally help control inflammation. This leads to an imbalance between Th17 cells and Tregs, tipping the immune system toward excessive inflammation. In tissue samples from Crohn’s disease patients, we found evidence of this imbalance, suggesting that mast cells play a major role in driving harmful inflammation. These findings help us understand why inflammation becomes uncontrollable in diseases such as Crohn’s disease. They also suggest that targeting mast cells could be a promising strategy for new treatments
Relations entre signes cliniques, anomalies échographiques et lésions pulmonaires à l'autopsie chez des bovins âgés de moins de 2 ans et référés dans les écoles vétérinaires de Nantes et de Toulouse
No full textInternational audienc
Suspected congenital oesophageal stenosis in a cat
No full textInternational audienceA 6-week-old, female, British shorthair cat was presented with a 4-week history of regurgitation and a 2-day history of cough and dyspnoea. Thoracic radiographs revealed an alveolar pattern suggestive of pneumonia secondary to regurgitation, and antibiotic therapy was initiated. After identifying a smooth stenosis with no signs of inflammation or neovascularisation on endoscopy, and after ruling out an external oesophageal stricture through thoracic computed tomography scan and exploratory thoracotomy, two successive balloon dilations were performed. No regurgitation was observed thereafter. At 18 months post-procedure, the cat remained clinically normal. To our knowledge, this is the second case of suspected congenital oesophageal stenosis in a cat, which should be included in the differential diagnosis of regurgitation in kittens
Développement d’algorithmes de détection de poulets par imagerie pour le suivi d’indicateurs d’activité en élevage
No full textInternational audienceGuaranteeing consumers that broilers are produced in a way that respects animal welfare is the basis of the farming profession, but civil society is calling for greater transparency in farming practices. Farm welfare assessment methods are carried out punctually and require time and the presence of a trained observer. Image analysis, on the other hand, enables continuous, real-time measurements to be taken without disturbing the animals. The aim of this article is to evaluate the performance of a broiler detection algorithm based on image analysis and using artificial intelligence to quantify individual animal mobility. The majority of the images used to train the model, as well as the test database, reflect the commercial densities used in broiler farming. They are also representative of the different physiological stages of the broilers. The model achieves a detection rate of 80% across all ages. However, the sensitivity of the algorithms increases with the age, rising from 66% for 0-day-old broilers to 90% for 40-day-old broilers. As it stands, broiler detection is strongly linked to the number of pixels defining the animal. This detection model is the first step needed to carry out individual tracking over time and therefore over several successive images. The quality of this tracking is highly dependent on the system ability to detect the animals correctly, but also on their activity. Tracking performance is not discussed in this article. In view of the promising results, the data generated will be used to assess broiler welfare indicators and detect health problems early on in commercial broiler farms and could also be used in experimental farmsGarantir aux consommateurs une production de poulets respectueuse du bien-être animal est la base du métier d’éleveur, mais la société civile demande plus de transparence sur les pratiques d’élevage. Les méthodes d’évaluation du bien-être en élevage sont réalisées ponctuellement et nécessitent du temps avec la présence d’un observateur formé. A l’inverse, l’analyse d’images permet d’effectuer des mesures en continu et en temps réel sans perturber les animaux. L’objectif de cet article est d’évaluer les performances d’un algorithme de détection de poulets basé sur l’analyse d’images et utilisant l’intelligence artificielle pour quantifier la mobilité individuelle des animaux. La majorité des images utilisées pour l’entrainement du modèle, ainsi que la base de données de test, reflètent les densités commerciales utilisées en élevage de poulets. Elles sont également représentatives des différents stades physiologiques des poulets. Le modèle atteint un taux de détection de 80 % tous âges confondus. La sensibilité des algorithmes augmente cependant avec l’âge des poulets, passant de 66 % pour les poulets de 0 jour à 90 % pour ceux de 40 jours. En l’état, la détection des poulets est fortement liée au nombre de pixels qui définissent l’animal. Ce modèle de détection est la première étape nécessaire pour effectuer un suivi individuel dans le temps et donc sur plusieurs images successives. La qualité de ce suivi dépend fortement de la capacité du système à détecter correctement les animaux, mais aussi de leur activité. Les performances de suivi ne sont pas exposées dans cet article. Au vu des résultats prometteurs, les données générées seront utilisées pour l’évaluation d’indicateurs de bien-être des poulets et la détection précoce de problèmes de santé en élevages commerciaux de poulets et pourraient l’être aussi dans les élevages expérimentaux
Les réseaux d’épidémiosurveillance des carnivores domestiques : Présence et fonctionnement dans le monde
No full textIn France, there is no epidemiosurveillance system for domestic carnivores. The implementation of such a network could enable us to monitor the emergence of epidemics at departmental, regional and international levels, and to act accordingly. This thesis is a systematic review focusing on domestic carnivore epidemiosurveillance networks, their presence and operation worldwide. This review was carried out using 54 articles, extracted from 3 different databases (Pubmed, CabAbstract and Web of Science), and using data from domestic carnivore epidemiosurveillance systems around the world. Eighteen networks on 6 continents were identified. Of these, 16% are active surveillance networks, and 67% are specific passive surveillance networks. These different systems monitor populations ranging from 1,000 to over 1 million individuals. The data and criteria monitored are manifold, ranging from leishmaniasis surveillance for 100% of active systems, to the monitoring of any anomaly detected during a check-up by the attending veterinarian. These systems make it possible to monitor the spread of diseases of major importance to domestic carnivores, and provide new avenues for research and reflection.En France, il n’existe pas de système d’épidémiosurveillance des carnivores domestiques. L’implémentation d’un tel réseau pourrait permettre de surveiller l’émergence d’épidémies au niveau départemental, régional, international et de pouvoir agir en conséquence. Cette thèse est une revue systématique centrée sur les réseaux d’épidémiosurveillance des carnivores domestiques, leur présence et leur fonctionnement dans le monde. Cette revue a été réalisée grâce à 54 articles, extraits dans 3 bases de données différentes (Pubmed, CabAbstract et Web of Science), et utilisant des données issues de systèmes d’épidémiosurveillance des carnivores domestiques dans le monde. Dix-huit réseaux présents sur 6 continents ont ainsi pu être identifiés. 16% d’entre eux présentent une surveillance active, et 67% des réseaux de surveillance passive sont spécifiques. Ces différents systèmes surveillent des populations comprises entre 1000 et plus de 1 million d’individus. Les données et critères surveillés sont multiples, allant de la surveillance de la leishmaniose pour 100% des systèmes actifs, à la surveillance de toute anomalie détectée lors d’un contrôle chez le vétérinaire traitant. Ces systèmes permettent de surveiller et de monitorer la propagation d’affections d’importance majeure pour les carnivores domestiques et d’apporter des pistes de recherche et de réflexion nouvelles
Appréhender la biosynthèse des lipides via des méthodes de traçage isotopique
No full textInternational audienceLipids play a vital role in physiological mechanisms, exhibiting diverse structures such as acyl chains, polar heads, and cycles. While lipidomics offers a snapshot of the lipidome at a specific moment, it lacks dynamic insights. Isotopic labeling experiments, utilizing stable isotopes like deuterium, 13C, or 15N, enable real-time tracking of metabolite incorporation. This approach significantly enhances our understanding of metabolic pathways, fluxes, and turnover.Experimental protocols for isotopic labeling can vary, including bolus injections or prolonged administration of isotopic tracers. Mass spectrometry, combined with chromatography, is essential for detecting compound enrichment. Studying fatty acids is relatively straightforward; deuterated water or 13C-glucose can be used to monitor de novo lipogenesis. An established analytical workflow involves Bligh and Dyer extraction followed by GC-MS with chemical ionization. The raw data is processed using IsoCor software to calculate average enrichment.For complex lipids, isotopic tracers can be introduced into either acyl chains or polar heads, depending on the study's objectives. Various analytical methods, including those specific to sphingolipids and global lipidomics, employ a reversed-phase column and an Exploris 240 mass spectrometer. Data-dependent acquisition techniques allow for the study of specific fragments and the detection of enrichment.Isotopic labeling experiments present challenges in tracking lipid metabolic pathways. However, preliminary experiments have facilitated the development of multiple workflows. Effective data processing is critical for detecting specific compound enrichment, and several software tools have been evaluated for this purpose