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Human milk vs. cow-milk based infant formula proteins: structure, digestion and physiological impacts
No full textInternational audienceThis review examines the differences in protein composition, digestion, and physiological effects on infants between human milk (HM) and infant formula (IF). The World Health Organization recommends exclusive breastfeeding for the first 6 months of life due to the numerous health benefits associated with it. However, when this is not possible, IF is used as an alternative. Differences between HM and IF remain, particularly in terms of protein composition and structure. Further optimization of IF is needed to better mimic HM and provide similar health benefits. Further improving IF formulation requires implementing a promising strategy, which in turn requires a thorough understanding of the mechanisms of protein digestion and amino acid (AA) absorption, as well as the metabolic and physiological effects of protein composition and structure. These are often altered by heat treatment and processing in IF. The main differences in the protein composition and structure of HM and IF are presented, including a synthesis of knowledge on the non-protein nitrogen (NPN) fraction. This fraction is too often neglected in milks, despite accounting for one fifth of the total nitrogen in HM. The influence of the protein composition and structure of HM and IF on the digestion of dietary protein and dietary AA absorption is compared, highlighting the need for data on the postprandial AA profile in infants from well-designed clinical trials. Finally, this review examines the differences in protein composition and digestion between HM and IF that lead to distinct metabolic, physiological and microbial outcomes. Future research should focus on understanding the role of partially digested proteins and the NPN fraction in shaping the infant gut microbiota and overall health
Dark side of the honeymoon: reconstructing the Asian x European rose breeding history through the lens of genomics
No full textInternational audienceRoses hold significant symbolic value in Western cultural heritage, often serving as a symbol of love and romance. Despite their ancient cultivation, the appreciation for the phenotypic diversity of roses emerged relatively recently, notably during the 19th century. This period is characterized by a remarkable expansion in the number of varieties, from around 100 to over 8,000, representing a golden age for roses. To trace the history of rose breeding in Europe and unveil genetic changes during this period, we gathered phenotypic and genetic data from 204 accessions. These included botanical roses and varieties cultivated between 1800 and 1910. Whole-genome sequences from 32 accessions were also included. Our analysis revealed a temporal shift in the genetic makeup, transitioning from a historical European to a near-Asian genetic background within a few generations. This shift was accompanied by a notable reduction in genetic diversity, attributed to the backcrossing with the less diverse Asian genepool, plus some genomic signatures of selection. We have generated the largest GWAS catalog for rose to date, offering a valuable resource for future breeding initiatives. We emphasize the critical importance of preserving ancient rose collections to safeguard diversity and ensure a sustainable breeding for the long term
Clustering of milk lactose dynamics across lactation in dairy cows
No full textInternational audienceInterest in lactose content (LC) has grown as an indicator of udder health and metabolic disorders. Variability of LC dynamics across lactation has not been described and could help to clarify LC variations due to health or metabolic issues. The aim of this study was to identify distinct patterns of LC dynamics, and assess environmental and genetic contributions. To this end, 1,980,693 test-day records from 183,150 Holstein cows across 2,239 herds in France were analysed. Each cow had at least 2 records in the first 90 d and 4 between 7–300 DIM, averaging 7.3 records/cow. A functional principal component analysis was used to describe LC dynamics across lactation. This approach involves smoothing the LC curves for each cow and then summarising their overall shape using 3 principal components: average LC level across lactation, LC slope and LC level in mid-lactation. LC dynamics were clustered into 6 groups (G). The first 3 groups, representing 86% of the data, shared similar dynamics with minimal LC slopes (<0.01 % per month) and differed in average LC levels (G1: 5.00, G2: 4.79, G3: 4.60%). LC genetic value (G1: 0.59, G2: -0.15, G3: -0.82) and cow parity (G1: 1.8, G2: 2.6, G3: 3.2) explained 68% of the average LC levels. The remaining groups showed LC levels similar to those of G2 until 150 DIM. Thereafter, two showed negative slopes (G4: -0.07% and G5: -0.13% per month), and one a positive slope (G6: +0.05% per month). The variation in LC slope was partly explained by environmental factors (15%). Winter calving were associated with G4 and G5, and summer calving with G6. The proportion of culling during or after the current lactation was higher for G3, G4, and G5 (31-46%) compared to G1, G2, and G6 (16-25%). As a result, clustering lactose revealed distinct LC dynamics with genetic LC values explaining the average LC level. The LC slope variations was partly explained by environmental factors, while the remaining unexplained variability may be caused by health issues, e.g. udder or metabolic disorders, leading to higher rate of culling
Establishing assessment criteria for soil bioindicators: insights from case studies in Europe
No full textInternational audienceThe new EU Soil Strategy aims to restore soil health across Europe by 2050, requiring policy-relevant indicators with robust assessment criteria to control and monitor its achievement. Despite the importance of biological conditions for soil health, few EU Member States have currently established criteria (e.g., target or threshold values) for evaluation of monitoring data. Our study examines the challenges and opportunities in developing such criteria based on the normal operating ranges of bioindicators in the context of soil units (i.e., homogenous soil texture and land use). Leveraging on national case studies across Europe, we find that for most bioindicators criteria could not be defined, due to data insufficiency and environmental bias. Only in France could normal operating ranges be established for earthworms, for some soil units. We identify priorities for the development of robust assessment criteria: (1) Harmonization of evaluation units and definitions, to minimize disparities in current soil texture and land use classifications between Member States, that complicate comparability of evaluation across Europe; (2) Inclusion of climatic-region specific thresholds/targets in addition to land use and soil texture; and (3) Standardization of protocols to reduce the observed variability in methods for sampling and data aggregation. As a temporary solution to optimize monitoring sampling efforts, guidelines for dealing with data deficiencies and pseudo-replication are proposed. On the longer term, our findings highlight the importance of integrated data systems and standardised frameworks for monitoring bioindicators to evaluate progress towards achievement of the EU soil health targets
Crack patterns induced by auto-stratification in drying sessile droplets of dairy proteins
No full textInternational audienceExploring the interfacial mechanisms involved in the evaporation of colloidal solutions is currently an open question with potential biomedical and industrial applications. In biological systems, unraveling evidence of selfarrangement is even more challenging due to the different size, structure and charge of their multi-components.In this work, we study the evaporation dynamics in mixes of dairy proteins, i.e., whey proteins and casein micelles. Combining the observation of crack formation in drying droplets and the evaluation of the elastic response in films during the evaporation, we highlight interfacial stratification resulting in the external accumulation of whey proteins. We also relate such preferential segregation to the mechanical properties of the dry matrices, showing that whey protein overrepresentation confers a brittle behavior to the mixes. These experimental results enable the development of a first predictive model of the elastic modulus for biocolloid binary mixes, taking into account their deformability and different ratio in the samples. Unraveling the link between colloid selfarrangement and the evolution of skin properties during the evaporation is a first step towards controlling structure and use properties of the dry particles composing dairy powders
Application of and Soluble Fiber in the Production of Lactose-Hydrolyzed Milk Powders
No full textInternational audienceDried dairy products containing hydrolyzed lactose pose significant technological challenges during spray drying, including reduced solubility, increased stickiness, and enhanced Maillard reaction (MR). This study evaluated the effects of transglutaminase (TGase) and soluble fiber on the physicochemical and structural properties of hydrolyzed lactose whole milk powder, aiming to mitigate these limitations. Six formulations of whole milk powder were developed. The addition of TGase resulted in increased particle size. Lactose hydrolysis intensified the MR, as evidenced by higher levels of 5-hydroxymethylfurfural (HMF) and increased yellowness in the hydrolyzed samples. Notably, TGase reduced HMF formation in the lactase-treated samples, suggesting a potential inhibitory effect on the MR post-processing. Microstructural analysis revealed particle agglomeration in the hydrolyzed samples and larger particle diameters in treatments containing TGase. Moreover, TGase application led to increased protein polymerization, as demonstrated by the presence of high-molecular-weight bands on electrophoretic profiles, indicating protein cross-linking. After five months of storage at ambient temperature, samples containing TGase exhibited lower HMF content and reduced browning intensity. Accelerated storage at 50°C further intensified browning in hydrolyzed formulations. However, TGase and fiber were not effective in preventing browning under elevated storage temperatures. Overall, the incorporation of TGase and soluble fiber appears to offer promising strategies to improve the stability and quality of hydrolyzed lactose milk powders, though further research is warranted to optimize their functional performance. This study is part of the international research project CAPES-COFECUB, conducted through a collaborative partnership between the Federal University of Juiz de Fora (UFJF), Brazil, and STLO, INRAe, Institut Agro, Rennes, France
Complementing single-species assessment models with age- and time-varying natural mortality: Insights from holistic ecosystem models
No full textInternational audienceIntegrating information on ecosystem dynamics into single-species stock assessment has been recommended for fisheries management to head towards Ecosystem-Approach to Fisheries Management (EAFM). This paper proposes a sensitivity analysis of single-species assessments in relation to the implementation of time-varying natural mortality (M). Time-varying estimates from a holistic ecosystem model were implemented in exploratory Celtic Sea gadoid stock assessments. Two species were selected to disclose different temporal patterns in M: whiting (Merlangius merlangus) displaying a trend and haddock (Melanogrammus aeglefinus) exhibiting high variability with no trend. Implementing overall higher M levels increases Spawning Stock Biomass (SSB) and decreases average fishing mortality at age (Fbar) in both cases. Here, time-varying values induce reference points modification. Introducing a trend in M improves the assessment quality for whiting, while shifting the stock status from fully exploited to overexploited for several years. Integrating high M variability for haddock induces minimal changes in assessment quality and stock status. In both cases, short term projected sustainable catch level was reduced by 14%. Despite uncertainty around estimates, results suggest that integrating M accounting for a varying predation is crucial, especially when M disclose a trend. Future research should focus on comparing M estimates across various sources, including ecosystem models, and benchmarking the single-species models' sensitivity to time-varying values
Avis de l’Anses relatif à « l’évaluation du risque lié à Ceratobasidium theobromae pour les DROM »
No full textAnses. (2024). Demande d'avis relatif à l'évaluation du risque lié à Ceratobasidium theobromae pour les DROM. Saisine 2024-SA-0147. Maisons-Alfort : Anses, 40 p.L’Anses a été saisie le 09 octobre 2024 par la Direction générale de l’alimentation pour la réalisation de l’expertise suivante : Évaluation du risque lié à Ceratobasidium sp. pour les DROM.1.1 Contexte de la saisineLa maladie du balai de sorcière du manioc (cassava witches' broom disease, CWBD) est une maladie dévastatrice de plantations en Asie du Sud-Est. Les symptômes caractéristiques du CWBD classiquement attribués à la présence de phytoplasmes sont le nanisme et la prolifération de pousses faibles et grêles sur la tige du manioc en forme de balai. En 2023, le CWBD observé sur manioc au Laos, au Cambodge et au Vietnam a été associé - en l’absence de tout phytoplasme - à un champignon, du genre Ceratobasidium (Leiva et al., 2023). Ce dernier s’est révélé très proche génétiquement de C. theobromae, agent pathogène responsable de la maladie vascular streak dieback (VSD) sur cacao où il provoque les mêmes symptômes. En 2024, une étude par séquençage du génome d’une souche de Ceratobasidium sp., isolée à partir de manioc produit dans la même région présentant des symptômes du CWBD, et cultivée in vitro, identifie le champignon comme étant un isolat de C. theobromae (Gil‑Ordóñez et al., 2024).Dès mars 2023, des signalements avaient été recueillis par la Direction de l’Environnement, de l’Alimentation, de l’Agriculture et de la Forêt (DGTM/DEAAF) au sujet de la présence d’une maladie se propageant sur les plants de manioc sur le territoire Guyanais dans l’ensemble des communes productrices de cette culture dont les symptômes pouvaient s’apparenter à ceux de la CWBD. Missionnées par la DGTM, plusieurs campagnes de prospections et de prélèvements ont été effectuées par la Fédération Régionale de lutte contre les organismes nuisibles (FREDON) dans les différents bassins de production de manioc de mai 2023 à mai 2024. En l’absence de connaissances suffisantes de l’agent pathogène responsable de cette maladie, ce sont 211 échantillons qui ont été envoyés dans différents laboratoires afin d’identifier le ou les organisme(s) responsable(s) de la maladie. Au fil des mois, les différentesanalyses notamment mycologiques ont permis de mettre en évidence la présence systématique d’un champignon du genre Ceratobasidium.Une mission de chercheurs du Centre international d’agronomie tropicale, Colombie (CIAT) a été déployée du 13 au 17 mai 2024 en Guyane et a confirmé, par analyse de séquence d’un gène barcode et caractérisation morphométrique, l’identification d’une souche de Ceratobasidium sp. proche de celle de C. theobromae identifiée en 2023 en Asie du Sud-Est (Laos, Vietnam, Cambodge). Cette identification a été confirmée le 11 juillet 2024 par le laboratoire national de référence pour les champignons et les oomycètes (unité de mycologie, Laboratoire de la santé des végétaux, Anses) par analyses de séquence de code barre génétique, et PCR espèces-spécifique. La maladie a également été signalée dans l’État de ,l’Amapá au Brésil.Dans ce contexte, les services de l’Etat, appuyé par la FREDON, vont poursuivre les investigations dans l’ensemble des bassins de production pour affiner la situation phytosanitaire et des travaux de recherche vont être menés par le CIRAD pour acquérir des connaissances et, notamment déterminer les risques de passage du champignon sur d’autres espèces.La maladie, qui touche aussi bien les jeunes plants que les plants plus âgés de manioc, se traduit par le jaunissement et le flétrissement des feuilles suivis par un dessèchement des tiges, de l’apex jusqu’aux racines, pouvant conduire à la mort du plant. En cas de reprise de végétation, peuvent être constatées l’émission de tiges tordues et/ou pousse erratique des feuilles (en balai de sorcière). Outre l’impact significatif sur le rendement et la qualité des tubercules, la maladie limite aussi fortement la disponibilité en matériel végétal permettant de replanter les abattis (tiges) et compromet donc à l’échelle de la filière entière l’accès à cette ressource alimentaire.D’un point de vue réglementaire, ni Ceratobasidium sp. ni C. theobromae ne sont réglementés par les textes s’appliquant dans les DROM (Arrêté du 3 septembre 1990). Cependant, le champignon C. theobromae est listé comme organisme de quarantaine au Brésil.1.2 Objet de la saisineCompte tenu des dégâts observés sur le manioc en Guyane et de la menace que pourrait représenter Ceratobasidium sp. pour d’autres cultures d’intérêt agronomique telle que le cacaoyer, une évaluation du risque phytosanitaire sur Ceratobasidium sp. pour les DROM (Guyane, Antilles, La Réunion, Mayotte) s’avère nécessaire.Une attention particulière sera portée à la description des méthodes de diagnostic disponibles et des mesures de gestion mobilisables (y compris en termes de sécurisation du matériel de multiplication et la gestion des terres contaminées).Il a été convenu, lors d’un échange avec le demandeur, qu’il serait envisageable de découper la zone ARP (zone pour laquelle l’Analyse du Risque Phytosanitaire est réalisée) qui englobe actuellement tous les DROM et réaliser l’évaluation du risque en deux parties : la Guyane (territoire où l’organisme nuisible est présent) et les autres DROM regroupés.Par ailleurs, une publication scientifique parue le 17 novembre 2024 et rédigée par Pardo et al. (2024) précise que le champignon détecté sur le manioc en Guyane française est Ceratobasidium theobromae. Compte tenu de cette précision relative à l’espèce et en accord avec le demandeur, le périmètre de la saisine est revu et l’évaluation du risque phytosanitaire porte désormais sur C. theobromae
Dietary pentadecanoic acid supplementation at weaning in essential fatty acid-deficient rats shed light on the new family of odd-chain n-8 PUFAs
No full textInternational audiencePentadecanoic acid (C15:0) is a saturated odd-chain fatty acid (OCFA), mainly found in dairy products. Its physiological and nutritional effects are still unknown, yet some recent evidences suggest it might be beneficial to human health. Moreover, pentadecanoic acid has recently been suspected of having essential roles in humans, although the mechanisms are not described. We therefore questioned the potential essentiality of this fatty acid (FA). We investigated in vivo the effect of a C15:0 supplementation on essential fatty acid (EFA) deficient Wistar rats. Female rats were fed an EFA-deficient diet 2 weeks before mating, during pregnancy and lactation. Weaned pups were fed the EFA-deficient diet or were switched to a diet supplemented with C15:0 or linoleic acid (LA) for 11 weeks. A control group was fed with EFA during the whole study. Since LA deficiency is known to induce growth delay, weights were measured throughout the experiment and FA content in collected tissues were analyzed to evaluate biochemical markers of the deficiency. As expected, EFA-deficient rats showed growth retardation, compared to control rats. Supplementation of C15:0 at weaning increased early growth rate compared to deficient animals, as also did the supplementation of C18:2 n-6. Furthermore, the supplementation of C15:0 in the diet of EFA-deficient animals induced the previously undescribed synthesis of odd-chain PUFAs of the n-8 family (C19:3, C21:3 and C21:4 n-8). These results suggest dietary C15:0 might counteract EFA induced growth retardation, possibly through the synthesis of odd-chain n-8 PUFAs, yet mechanisms are to be deciphered for further validation
Chapter 16 - Habitat degradation impacts on marine fish
No full textInternational audienceThe ocean supports a wide range of economic activities, including the harvesting of food, shipping, seabed mining, offshore hydrocarbon exploration and exploitation, tourism, and recreation, among others, all of which have significantly contributed to habitat degradation of coastal and marine ecosystems. This has dramatically impacted ecosystem function and services provided by these habitats, with detrimental consequences for marine fish. Over 90% of fish species are impacted by at least one anthropogenic stressor operating indirectly via their habitat, and about 70% are impacted by two or more, chiefly among which are chemical pollutants, eutrophication, invasive species, noise, and physical habitat loss. Still, rebuilding marine life, including fish populations, could be realized if major pressures are mitigated