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A Decade of Salmonella Resistance in the French Pig and Pork Industry: Antibiotics, Heavy Metals, and Farm-to-Fork Transmission
No full textInternational audienceBackground and objectives: The emergence of antibiotic-resistant Salmonella in the pig and pork industry poses a growing public health challenge, as this pathogen remains a major cause of foodborne infections associated with pork consumption in France and across the European Union (EU) [1]. Since the EU prohibited the use of antibiotics as growth promoters in 2006, heavy metals such as copper, zinc, and silver, among others, have been utilized for their antimicrobial properties and as growth promoters throughout the production chain [2]. In Gram-negative bacteria, resistance genes for antibiotics and heavy metals have been reported to co-occur and, in some instances, co-localize on mobile genetic elements, potentially promoting their persistence and spread [3]. However, the mechanisms underlying this co-selection in Salmonella remain poorly characterized. This study, conducted within a One Health framework, aims to investigate heavy metal and antibiotic resistance genes, their co-localization, and potential cross-resistance mechanisms.Methods: A total of over 800 Salmonella strains, collected from the pig and pork production chain and human clinical cases between 2014 and 2024, were subjected to whole-genome sequencing using Illumina technology. Phylogenetic and pangenome analyses were performed to assess genetic diversity and the distribution of core and accessory genes. The resistome was characterized using multiple public databases, while the mobilome including plasmids, transposons, integrons, and integrative and conjugative elements was examined to predict possible co-localization of resistance determinants.Results: The predominant Salmonella serovars identified across the pig and pork production chain in this studied panel included S. Typhimurium, its monophasic variant, and S. Derby, alongside 26 additional serovars. Serovar effective varied across production stages, with the highest distribution observed at the livestock and slaughterhouse levels. Preliminary analysis revealed that antimicrobial resistance genes against aminoglycosides, penicillin, tetracyclines, and sulfonamides were the most frequently detected in Salmonella isolates. Notably, genomic analyses revealed no resistance genes associated with carbapenemase.Conclusions: Ongoing genomic analyses are focused on identifying antibiotic- and heavy metals-resistant strains and assessing their potential for horizontal gene transfer, as well as possible cross-resistance between antibiotics and heavy metals commonly used in pig farming. These aspects will be further explored through long-read sequencing and phenotypic assays. The findings of this study will contribute to a better understanding of the persistence and spread of resistant Salmonella within pig and pork production systems in France and may inform targeted strategies to mitigate antimicrobial resistance.References[1] Bonardi, S. (2017b). Salmonella in the pork production chain and its impact on human health in the European Union. Epidemiology and Infection, 145(8), 1513–1526. https://doi.org/10.1017/s095026881700036x [2] Kyprianou, M. (2005b). Ban on antibiotics as growth promoters in animal feed enters into effect. In EU-wide Ban on the Use of Antibiotics as Growth Promoters in Animal Feed. https://ec.europa.eu/commission/presscorner/api/files/document/print/en/ip_05_1687/IP_05_1687_EN.pdf [3] Vats, P., Kaur, U. J., & Rishi, P. (2022). Heavy metal-induced selection and proliferation of antibiotic resistance: A review. Journal of Applied Microbiology, 132(6), 4058–4076. https://doi.org/10.1111/jam.1549
Non‐Thermal Plasma Oxidation Processes for the Removal of Pharmaceuticals in Water: Diclofenac and Diclofenac/Carbamazepine Mixture
No full textInternational audienceThe Non‐Thermal Plasma (NTP) process was studied for the removal of pharmaceutical pollutants (diclofenac (DCF) and carbamazepine (CBZ)) from water. In the individual treatment, at 0.2 W, showed 86% DCF and 63% CBZ degradation in 40 min, forming hydroxylated and nitro‐products. The same degradation efficiency was achieved for each compound in the mixed pollutant systems, and a complete degradation was attained after 90 min. By comparing the intermediate products, the formation of nitro‐products was higher in the mixed systems compared to their individual solutions treatment. The study concluded that NTP efficiency should be evaluated on pollutant mixtures rather than single compounds. Complementary biological analyses revealed the potential cell toxicity induced by generated products, highlighting the pertinence for toxicological analyses
Effects of low-purine diet supplemented with Sida acuta Burm. f. on growth performance, purine deposition, and biomolecules in slow-growing chickens
No full textInternational audienceObjective: This study investigated the effects of a low-purine (Pu) diet supplemented with Sida acuta Burm. f. (SA) on growth performance, serum uric acid (SUA), and meat quality, including chemical composition, biomolecules, and purine deposition, in slow-growing Korat chickens (KRC).Methods: A total of 480 mixed-sex one-d-old KRC were randomly allocated into five groups with six replicates each (16 chicks/replicate) using a 1+2×2 augmented factorial experiment in a completely randomized design. Five experimental diets were as follows: a control (basal diet), two diets with 30% and 45% lower purine levels than the control (–30% and –45% Pu), each supplemented with two levels of SA (0.3% and 0.6% SA), respectively. After sex determination, all subsequent analyses were conducted exclusively on female birds.Results: KRC fed a –30% Pu diet supplemented with 0.6% SA showed reduced hypoxanthine and total purine deposition in major breast muscle (Pectoralis majora) without negative effects on growth performance, SUA levels, meat quality, chemical composition, biomolecules, and protein secondary structures comparable to the control group. Birds fed a −45% Pu diet, supplemented with either 0.3% or 0.6% SA, exhibited impaired growth performance and without significant changes in major breast muscle hypoxanthine or total purine content. Correlation analysis revealed that the –30% Pu diet supplemented with 0.6% SA was positively correlated with reduced hypoxanthine and total purine content, while showing negative correlations with lipid content and β-turn structure.Conclusion: A 30% reduction in dietary purines combined with 0.6% SA supplementation effectively decreased purine deposition in chicken meat, contributing to the production of healthier chicken meat product. Further studies are needed to investigate the molecular mechanisms and metabolic pathways, which will enable breeders to advance the development of Pu chicken meat production
Assessment of the interest price of three products from black soldier fly larvae used to feed fast-growing broilers
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Optimistic bilevel scheduling with job selection on a single machine
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Comparison queries generation using mathematical programming for exploratory data analysis
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Solution methods for the VRP with sharing of deliveries between producers in local food logistic
No full textInternational audienceThis study addresses the logistical challenges in Short Food Supply Chains (SFSC), where producers face high logistical costs. A new variant of the Vehicle Routing Problem (VRP) is proposed, enabling producers to share their deliveries with partner producers. With a partner producer, a producer can either drop off goods for a customer (to be served by the partner producer) or pick up goods for a customer they will visit themselves during their routes.Although solving the Vehicle Routing Problem (VRP) is a key area in optimization, with certain variants tailored to the specificities of SFSC, such as Pickup and Delivery or split deliveries, few studies address a delivery sharing aspect like this.Three heuristic methods were tested: GRASP (Greedy Randomized Adaptive Search Procedure), ILS (Iterated Local Search), and VNS (Variable Neighborhood Search), which systematically explores multiple neighborhoods. Initial results show a significant reduction in logistical costs thanks to the sharing approach, while also highlighting an imbalance in the workload distribution between producers.Mots clés -Circuits CourtsAlimentaires de Proximité, VRP, mutualisation, méta-heuristiques Résumé Cette étude traite des défis logistiques dans les Circuits Courts Alimentaires de Proximité (CCAP), où les producteurs sont confrontés à des coûts logistiques élevés. Une nouvelle variante du problème de tournées de véhicules (VRP) est proposée, permettant aux producteurs de mutualiser leurs livraisons avec d'autres producteurs partenaires. Avec un producteur partenaire, un producteur peut soit lui déposer des marchandises pour un client (que ce producteur servira), soit prendre des marchandises pour un client qu'il visitera lui-même lors de ses tournées. Bien que la résolution du Problème de Tournées de Véhicules (VRP) soit un domaine clé en optimisation, avec certaines variantes adaptées aux spécificités des CCAP, comme le Pickup and Delivery ou les livraisons fractionnées, peu d'études abordent un aspect de mutualisation des tournées comme celui-ci. Trois méthodes de résolutions approchées ont été testées : GRASP (Greedy Randomized Adaptative Search Procedure), ILS (Iterated Local Search), et VNS (Variable Neighborhood Search), qui explore plusieurs voisinages de manière systématique. Les premiers résultats montrent une réduction significative des coûts logistiques grâce à la mutualisation, et mettent en évidence un déséquilibre dans la répartition des charges entre producteurs.</div
Written Production in Children, Adolescents, and Adults with Autism Spectrum Disorder—A Systematic Review from a Lifespan Perspective
No full textInternational audiencePurpose: While previous studies and reviews have investigated writing skills in individuals with autism spectrum disorder (ASD), few have explored how their strengths and weaknesses evolve across the lifespan, which is the focus of our paper. Specifically, we examined how theoretical models explain differences in the motor and cognitive components of written production between autistic and non-autistic (NA) individuals from a lifespan perspective.Method: We conducted a systematic literature review of experimental studies published between January 2000 and December 2023, identified through ScienceDirect, PubMed, and Web of Science. Studies were included if they were experimental, published in peer-reviewed journals, focused on written production through a writing task, and assessed participants with an ASD diagnosis without co-occurring intellectual disability. A qualitative assessment of study quality was conducted to reduce bias. The characteristics and main findings of each study were analyzed, with a focus on the motor and cognitive components of written production. Our analysis spanned the lifespan, encompassing children, adolescents, and adults.Results: Findings from 36 studies indicated that the written production of autistic individuals exhibits specificities at each stage of their lives. When challenges are observed, they can often be attributed to reduced productivity and/or lower content quality.Conclusion: Based on cross-sectional studies, the developmental trajectory of writing appears to differ between some autistic and NA individuals. The results are discussed in light of theoretical models of ASD