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International audience; De nombreuses études au cours des 30 dernières années ont montré les effets des pratiques agricoles sur les composés du lait. Des combinaisons de pratiques peuvent avoir des effets antagonistes ou synergiques sur les composés du lait, mais ces effets combinés restent sous-étudiés. La recherche doit se concentrer sur la qualité intrinsèque globale du lait (incluant les dimensions sensorielles, technologiques, sanitaires et nutritionnelles) et identifier les combinaisons qui peuvent l'optimiser. L'objectif de cette étude était d'identifier quelles combinaisons de pratiques d'élevage obtenaient les meilleurs scores pour les dimensions sensorielles, technologiques, sanitaires, nutritionnelles et pour la qualité intrinsèque globale du lait. Quatre-vingt-dix-neuf fermes privées ont été visitées une fois chacune pour échantillonner leur lait en vrac et étudier leurs pratiques agricoles. Les pratiques enquêtées concernaient les caractéristiques du troupeau, la gestion de l'alimentation, les conditions d'hébergement, et les conditions de traite et de stockage du lait le jour de l'essai. Des analyses de lait de tank ont ​​été conçues pour évaluer la qualité intrinsèque globale du lait pour 2 produits cibles : le fromage au lait cru et le lait demi-écrémé UHT. Des arbres de régression ont ensuite été utilisés pour identifier les combinaisons de pratiques agricoles qui ont obtenu les meilleurs scores sur chaque dimension et sur la qualité intrinsèque globale du lait. La race et le régime alimentaire (type de fourrage) étaient les facteurs les plus influents pour les dimensions sensorielles et sanitaires et pour les scores des dimensions technologiques et nutritionnelles, respectivement, dans l'évaluation du fromage. La qualité globale du fromage était fortement corrélée positivement avec ces scores à 4 dimensions. Par conséquent, la race et le régime alimentaire sont apparus comme les pratiques les plus influentes dans l'arbre de régression pour la qualité globale du fromage. Cependant, les combinaisons de pratiques ayant abouti aux meilleurs scores de qualité diffèrent selon la dimension étudiée et le produit visé. Cela suggère que les conseils sur les pratiques d'élevage pour améliorer la qualité intrinsèque du lait doivent être adaptés en fonction de la destination finale du lait collecté. Cette approche innovante combinant des données à la ferme et des arbres de régression fournit aux gestionnaires d'exploitations un outil précieux et pratique pour hiérarchiser les pratiques en fonction de leur rôle dans l'élaboration de la qualité du lait, et pour identifier les combinaisons de pratiques qui favorisent une bonne qualité du lait et les seuils ou modalités de pratique. nécessaires pour y parvenir. Cela suggère que les conseils sur les pratiques d'élevage pour améliorer la qualité intrinsèque du lait doivent être adaptés en fonction de la destination finale du lait collecté. Cette approche innovante combinant des données à la ferme et des arbres de régression fournit aux gestionnaires d'exploitations un outil précieux et pratique pour hiérarchiser les pratiques en fonction de leur rôle dans l'élaboration de la qualité du lait, et pour identifier les combinaisons de pratiques qui favorisent une bonne qualité du lait et les seuils ou modalités de pratique. nécessaires pour y parvenir. Cela suggère que les conseils sur les pratiques d'élevage pour améliorer la qualité intrinsèque du lait doivent être adaptés en fonction de la destination finale du lait collecté. Cette approche innovante combinant des données à la ferme et des arbres de régression fournit aux gestionnaires d'exploitations un outil précieux et pratique pour hiérarchiser les pratiques en fonction de leur rôle dans l'élaboration de la qualité du lait, et pour identifier les combinaisons de pratiques qui favorisent une bonne qualité du lait et les seuils ou modalités de pratique. nécessaires pour y parvenir.

International audience; We present a preliminary study of a wearable system to monitor biomarkers for dairy and suckling cattle. Finding the optimal location on the cow body (ears) and designing the adapted microneedles to reach the interstitial fluids underneath the cow skin are the two points addressed here.For the selection of the location, 4 breeds of suckling cows (Aubrac, Charolaise, Lim-ousine, Salers) and 3 breeds of dairy cows (Abondance, Montbe ⠁liarde, Holstein) were chosen. Measurements of the thickness of the ear tissues were conducted on three areas of the ear (top, apex and base of the pinna), on the external and internal sides. Results show that the apex of the pinna, external side, is the best area for microneedle implantation with an implantation window of 1403 +/- 589 mm (DeepDe), considering all breeds. To reach this implantation window located between the stratum corneum and the cartilage, the microneedle has to pass through 1323 +/- 404 mm of tissues (SupDe), considering all breeds. From these results, a microneedle design was made on SolidWorks. With a conical shape 2.89 mm in height and a conical channel 300 mm in diameter (at the tip of the microneedle), the model was made using 3D printing. The resulting microneedles respect the SolidWorks design with fair accuracy. They were connected to a microfluidic channel for sampling or releasing fluids.

International audience

International audience; Flavan-3-ols are among the most consumed polyphenols by humans and have been shown to prevent cardiovascular diseases. They are found in plant as monomers and mainly as oligomers such as procyanidins. The majority reaches the colon where the microbiota converts them into phenolic metabolites likely to participate in their health effects. While the metabolic pathways of the degradation of flavan-3-ols by the microbiota are relatively well described, only a few microorganisms and microbial genes involved in these pathways are known. We have previously shown that Eggerthella lenta metabolizes flavan-3-ol monomers and oligomers. Here, our aim was to identify E. lenta genes encoding enzymes degrading flavan-3-ols and to determine their prevalence in human gut metagenomes. By a transcriptomic approach (RNAseq) carried out with the type strain of E. lenta, coupled with the heterologous expression of the genes of interest in Escherichia coli, we have discovered two genes (fmber1, fmber2) encoding two benzyl ether reductases cleaving the C ring of the monomers and an operon of two genes (pber) catalyzing this reaction on the dimers of type-B procyanidins. Furthermore, two operons of three genes (cadh, ecadh) encoding enzyme complexes dehydroxylating the Bring of (+)-catechin and (-)-epicatechin have also been identified. These genes constitute good markers of flavan-3-ol metabolization in the gut. Their prevalence in human gut metagenomes suggested that 27% of individuals cannot convert flavan-3-ols into potential bioactive metabolites. These results raise the question of whether individuals who do not harbor these bacterial genes are at greater risk of developing cardiovascular disease.

International audience; Flavan-3-ols are a largely consumed subclass of flavonoids and are involved in the prevention of cardiovascular diseases [1]. The contribution of phenolic metabolites produced by the gut microbiota in the health effects of polyphenols (including flavan-3-ols) is currently an open field of investigation. Although a few bacterial species metabolize flavan-3-ol monomers [2] no bacterial isolates active on oligomers (called procyanidins) have been described. Knowing that the gut microbiota hydrolyzes procyanidins [3], our aim was to identify bacteria degrading flavan-3-ol oligomers and the degradation products. From human stools of three healthy individuals, culturomic approaches combined with screening for the metabolic activity of bacterial isolates by HPLC-DAD allowed us to obtain four strains of Eggerthella lenta and one strain of Flavonifractor plautii degrading (+)-catechin and (-)-epicatechin. The activity of these strains was then tested on B-type (DP2 to 4) and A-type (DP2) procyanidins and the metabolites generated were characterized by LC-ESI-MS / MS. These two species co-metabolized (+)-catechin and (-)-epicatechin into hydroxyphenylvaleric acid derivatives. Only E. lenta converted procyanidins while F. plautii alone or in co-culture with E. lenta did not show any activity towards procyanidins. The reaction catalyzed by E. lenta on dimers (B-type and A-type) corresponded to the opening of the C-ring of the terminal unit. This work is the first report of flavan-3-ol oligomers metabolization by the human gut bacterium E. lenta.

International audience; In context of global challenges facing agriculture, our article addresses the extent to which the synergistic nature of agroecological innovations may reconcile environmental and technical efficiency of farms. We develop an empirical model, namely conditional efficiency framework, which explicitly accounts for context-dependent drivers like synergy and complementarity of innovations. Using a sample of 567 banana farms in the French West Indies, our estimates confirm the complementarity effect since the joint adoption of agroecological innovations increases the technical efficiency scores much more than other drivers and each of the innovations taken in isolation. We also show that advice and extension services as well as human capital variables are key adoption levers for public policy since they reduce the variability of production and thus the risk associated with the joint adoption of the agroecological innovations.

International audience

International audience; Chez de nombreuses espèces, le stress maternel prénatal entraîne des modifications durables des caractéristiques individuelles physiologiques et comportementales. Cependant, ces effets prénatals peuvent être modulés par l’environnement postnatal et, en particulier, par les soins maternels. Si ce phénomène de remédiation a été largement étudié chez les mammifères, il reste très peu exploré chez les oiseaux. Or, nos travaux précédents, chez la caille japonaise, montrent que le phénotype comportemental du jeune peut être modulé à la fois par des influences maternelles prénatales (comme le stress maternel prénatal) et postnatales (avec les styles de maternage). Dans ce contexte, l’objectif de notre présente étude était d’analyser les interactions entre les effets pré- et postnatals en se questionnant sur la capacité des soins maternels à moduler voire contrecarrer les effets comportementaux du stress prénatal. Pour cela, des cailleteaux, issus de femelles stressées en phase de ponte, ont été élevés avec ou sans mère adoptive. Nos résultats montrent que, comparés aux jeunes non maternés, les jeunes élevés avec une mère adoptive expriment (1) de plus forts comportements exploratoires dans un nouvel environnement, (2) moins de néophobie face à un nouvel objet et (3) une plus faible sensibilité à la séparation sociale. Ainsi, les jeunes issus de femelles stressées mais maternés expriment globalement une réactivité émotionnelle plus faible que les jeunes issus de ces mêmes femelles mais non maternés. Nos résultats soulignent donc que, comme chez les mammifères, les soins maternels peuvent moduler voir potentiellement contrecarrer les effets du stress maternel prénatal également chez l’oiseau. Ces effets maternels postnatals semblent impliquer une modification des réponses maternelles selon les caractéristiques du jeune à l’éclosion, la femelle adaptant ses soins en fonction des comportements des jeunes. Ainsi, l’interaction des influences maternelles pré- et postnatales en jouant un rôle majeur dans l’ontogénèse des comportements apparait être un mécanisme clé dans les processus d’adaptation et d’évolution des populations.

International audience

In natural habitats, animals receive many stimuli that vary in place and time. In such habitats, they can express a wide range of behaviours that define the species’ “behavioural repertoire”. Farming or captive environments are designed to meet their basic biological needs (e.g. for rest, feeding), but are far less complex than natural habitats. Animals thus may not be able to express some of the behaviours from their repertoire and as a consequence experience boredom. The concept of environmental enrichment refers to a wide range of modifications to the environment of captive or farmed animals that offer adequate stimulation and facilitate the expression of highly motivated behaviour, thereby promoting positive emotions and improving animal welfare. Environmental enrichment can be divided into five (non-exclusive) categories: relational, feeding, occupational, physical and sensory enrichments. A good knowledge of the behaviour and the biology of the species is essential for the design of relevant enrichments. The benefits and drawbacks of enrichments need to be assessed in both short and long term by studying the use of enrichments in terms of occupancy value, the preference and motivation of animals to use them and the impact on welfare. To support positive animal welfare, high quality enrichment that engages animals over a long period of time should be seriously considered.

International audience

IntroductionToday, agriculture and livestock farming are facing environmental, social and health challenges. The agroecological transition is a possible response to these challenges. It requires changes in practices but also an evolution in farmers' ways of thinking and relationships with living things. Some diagnostics of farms, such as the global analysis of farms, behaviors and practices.MethodsWe therefore propose a holistic approach combining a global analysis of farms and a pragmatic approach to understand the functioning of agricultural production systems. This pragmatic turn enables to integrate the ways in which the farmer's reality is established, the performance of the system, the associated metrics and the farmer's relationship with life.Results and discussionUsing the example of a farm in transition, we show that it is the combination researcher's stance and allows for a renewed dialogue between research and farmers in the field.

International audience; The aim of this study was to characterize the effects of tannins on plant protein during sheep digestion using a digestomic approach combining in vivo (rumen) conditions and an in vitro digestive system (abomasum and small intestine). Ruminal fluid from wethers infused with a tannin solution or water (control) was introduced into the digester, and protein degradation was followed by liquid chromatography-tandem mass spectrometry (LC−MS/MS). Tannin infusion in the rumen led to a clear decrease in protein degradation-related fermentation end-products, whereas ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) protein was more abundant than in control wethers. In the simulated abomasum, peptidomic analysis showed more degradation products of RuBisCo in the presence of tannins. The effect of RuBisCo protection by tannins continued to impact Rubisco digestion into early-stage intestinal digestion but was no longer detectable in late-stage intestinal digestion. The peptidomics approach proved a potent tool for identifying and quantifying the type of protein hydrolyzed throughout the gastrointestinal tract.

Male calves of specialised dairy breeds are often considered as a by-product of low economic value. At present, they are either sent to veal farms-often requiring long transportation especially if the country of origin has no established veal sector-, sent to beef production units-with the problem of a low productive performance-, slaughtered at an early age, or euthanized on the farm. The mortality of male dairy calves is higher than that of female ones and that of beef calves. Biological factors can explain only part of the overmortality of male calves. Management factors are assumed to play a determining role, with less care provided to male than to female dairy calves due to their low economic value.

International audience; Highlights:• Additional carbon storage, net GHG budget, and cost of 8 agricultural practices.• MACC shows abatement potential of 40–60 MtCO2e.yr−1 for carbon price 55–250 €.tCO2e−1.• Key practices: agroforestry, hedges, cover crops, grasslands in crop sequences.• No “one size fits all strategy” due to heterogeneity across regions and practices.• French agricultural carbon sink potential is 5 times higher than anticipated by the government.Abstract:Following the Paris agreement in 2015, the European Union (EU) set a carbon neutrality objective by 2050, and so did France. The French agricultural sector can contribute as a carbon sink through carbon storage in biomass and soil, in addition to reducing GHG emissions. The objective of this study is to quantitatively assess the additional storage potential and cost of a set of eight carbon-storing practices. The impacts of these agricultural practices on soil organic carbon storage and crop production are assessed at a very fine spatial scale, using crop and grassland models. The associated area base, GHG budget, and implementation costs are assessed and aggregated at the region level. The economic model BANCO uses this information to derive the marginal abatement cost curve for France and identify the combination of carbon storing practices that minimizes the total cost of achieving a given national net GHG mitigation target. We find that a substantial amount of carbon, 36.2 to 52.9 MtCO2e yr-1, can be stored in soil and biomass for reasonable carbon prices of 55 and 250 € tCO2e-1, respectively (corresponding to current and 2030 French carbon value for climate action), mainly by developing agroforestry and hedges, generalising cover crops, and introducing or extending temporary grasslands in crop sequences. This finding questions the 3-5 times lower target of 10 MtCO2e.yr-1 retained for the agricultural carbon sink by the French climate neutrality strategy. Overall, this would decrease total French GHG emissions by 9.2 to 13.8%, respectively (reference year 2019).; Suite aux accords de Paris en 2015, l'Union européenne (UE) s'est fixé un objectif de neutralité carbone d'ici à 2050, tout comme la France. En plus de réduire les émissions de GES, le secteur agricole français peut contribuer à la neutralité carbone en tant que puits de carbone, par le stockage de carbone dans le sol et la biomasse. L'objectif de cette étude est de quantifier le potentiel de stockage additionnel et le coût d'un ensemble de huit pratiques stockantes. Les impacts de ces pratiques agricoles sur le stockage du carbone organique du sol et les rendements des cultures sont évalués à une échelle spatiale très fine, à l'aide de modèles de cultures et de prairies. L'assiette, le bilan GES net et le coût de mise en œuvre associés à chaque pratique sont également évalués et agrégés au niveau régional. Le modèle économique BANCO utilise ces informations pour générer la courbe de coût marginal d'abattement pour la France, et identifier la combinaison de pratiques stockantes qui minimise le coût total pour atteindre un objectif national donné d'atténuation des émissions de GES nettes. Nous montrons qu'une quantité non négligeable de carbone, de 36,2 à 52,9 MtCO2e an-1, peut être stockée dans le sol et la biomasse pour des prix du carbone raisonnables de 55 et 250 € tCO2e-1, respectivement (correspondant à la "valeur de l'action pour le climat" actuelle et 2030, fixée par le gouvernement français), et cela principalement par le développement de l'agroforesterie et des haies, la généralisation des cultures intermédiaires, l'introduction ou l'extension des prairies temporaires dans les séquences de culture. Ce résultat remet en cause l'objectif 3 à 5 fois inférieur retenu pour le puits de carbone agricole (10 MtCO2e.an-1) par la stratégie nationale bas carbone. Globalement, ce stockage additionnel de carbone permettrait de réduire les émissions totales de GES de la France de 9,2 à 13,8 %, respectivement (année de référence 2019).

International audience; Metabolome profiling in biological fluids is an interesting approach for exploring markers of methane emissions in ruminants. In this study, a multiplatform metabolomics approach was used for investigating changes in milk metabolic profiles related to methanogenesis in dairy cows. For this purpose, 25 primiparous Holstein cows at similar lactation stage were fed the same diet supplemented with (treated, n = 12) or without (control, n = 13) a specific antimethanogenic additive that reduced enteric methane production by 23% with no changes in intake, milk production, and health status. The study lasted 6 wk, with sampling and measures performed in wk 5 and 6. Milk samples were analyzed using 4 complementary analytical methods, including 2 untargeted (nuclear magnetic resonance and liquid chromatography coupled to a quadrupole-time-of-flight mass spectrometer) and 2 targeted (liquid chromatography-tandem mass spectrometry and gas chromatography coupled to a flame ionization detector) approaches. After filtration, variable selection and normalization data from each analytical platform were then analyzed using multivariate orthogonal partial least square discriminant analysis. All 4 analytical methods were able to differentiate cows from treated and control groups. Overall, 38 discriminant metabolites were identified, which affected 10 metabolic pathways including methane metabolism. Some of these metabolites such as dimethylsulfoxide, dimethylsulfone, and citramalic acid, detected by nuclear magnetic resonance or liquid chromatography-mass spectrometry methods, originated from the rumen microbiota or had a microbial-host animal co-metabolism that could be associated with methanogenesis. Also, discriminant milk fatty acids detected by targeted gas chromatography were mostly of ruminal microbial origin. Other metabolites and metabolic pathways significantly affected were associated with AA metabolism. These findings provide new insight on the potential role of milk metabolites as indicators of enteric methane modifications in dairy cows.

Séance : Mixité dans les systèmes d’élevage, polyculture élevage, exploitation et territoire; International audience; One of the principles of agroecology is that the management of animal and plant diversity within livestock farms can enhance their sustainability. To go beyond this theoretical principle, we analyze the farm operation and performance of multi-species livestock farms, i.e. farms where at least two animal species are raised. In grassland-based systems, the complementarity of sheep, cattle and horse grazing behaviour reduces the use of feed concentrates, especially for sheep. Parasite dilution in mixed grazing systems benefits small ruminants and horses, and makes it possible to reduce the number of anthelmintic treatments. Adding a small monogastric enterprise to a beef or dairy system makes it possible to value farm co-products (whey...); milk processing is often associated with on-farm processing and opens up the possibility of short-distribution channels of diversified food baskets, which enhance farm viability. Work organization plays a key role in the way different species are integrated on the same farm. Rather than focusing on the maximization of within-farm diversity only, what matters is to reach an overall consistency of the system that the farmer is able to manage. Finally, we discuss the obstacles to the scaling-out of multi-species livestock farms, linked to a socioeconomic system built to benefit from the economies of scale offered by specialisation. To overcome these obstacles, we propose levers upstream (innovating for multipurpose equipment and infrastructures), downstream (reorganizing the collect chain) and around these farms (revisiting training and advice) that must be thought out in a coupled manner.; L’agroécologie stipule que la gestion de la diversité animale et végétale au sein des exploitations d’élevage renforce leur durabilité. Pour aller au-delà de ce principe théorique, nous analysons ici le fonctionnement et les performances d’exploitations de polyélevage, c’est-à-dire de fermes dans lesquelles sont élevées au moins deux espèces animales. Dans les systèmes herbagers, la complémentarité des modes de pâturage des ovins, des bovins et des chevaux permet de réduire le recours aux aliments concentrés, en particulier pour les ovins. La dilution des parasites digestifs en pâturage mixte profite aux petits ruminants et aux chevaux, et permet d’envisager de réduire la fréquence des traitements anthelminthiques. Un atelier monogastrique de petite taille permet de valoriser les co-produits (petit lait...) ; la transformation laitière, créatrice de valeur ajoutée, et les faibles volumes de viande commercialisés sont bien adaptés à la vente en circuits courts. L’organisation du travail entre toujours en ligne de compte dans la manière d’articuler différentes espèces au sein d’une même exploitation. Plutôt que de vouloir maximiser coûte que coûte la diversité au sein du système, il s’agit avant tout de rechercher une cohérence d’ensemble que les éleveurs puissent gérer. Nous discutons enfin des freins au déploiement des fermes de polyélevage, liés à un système socioéconomique construit pour bénéficier des économies d’échelle offertes par la spécialisation. Pour dépasser ces freins, nous proposons des leviers en amont (innover pour des équipements et infrastructures polyvalentes), à l’aval (réorganiser la logique de collecte), et autour des exploitations d’élevage (revisiter la formation et le conseil) qui doivent être pensés de manière couplée.

Séance : Qualité des produits; International audience; This study proposes an adaptation of the methodologies of Botreau et al. (2018) and Rey-Cadilhac et al. (2021) forthe multi-criteria assessment of milk intended for the manufacture of raw milk cheese, concerning the environmentalimpacts of milk production and the quality of the milk obtained. A main contribution is to rely on rapid and operationalanalysis methods on a larger scale: mid-infrared and fluorescence spectroscopies milk analyzes and CAP'2ER®diagnostic results of the farm. On 15 grassland dairy farms located in Cantal, representative of three types ofadaptation to the territorial context, the multi-criteria evaluation model tested in this study proved to be sensitive.Among the 4 components of milk quality and the 5 components of environmental performance analyzed, only thehealth component of quality showed significant differences between the different farm profiles. A significant andpositive correlation is found between the risk of eutrophication and risk for health. Other trending correlations areanalyzed between the components of milk quality and environmental performance, in association with agronomicpractices.; La présente étude propose une adaptation des méthodologies de Botreau et al. (2018) et Rey-Cadilhac et al. (2021)pour l’évaluation multicritère du lait destiné à la fabrication de fromage au lait cru, concernant les impactsenvironnementaux de la production du lait et la qualité du lait obtenu. Une des contributions de ce travail est lerecours à des méthodes d’analyse rapides et opérationnelles à large échelle : analyses du lait en spectroscopies enmoyen infra-rouge et fluorescence, et résultats de diagnostic CAP'2ER® de l'exploitation. Sur 15 fermes laitièresherbagères situées dans le Cantal, représentatives de trois types d’adaptation au contexte territorial, le modèled’évaluation multicritère testé dans cette étude s’est avéré sensible. Parmi les 4 composantes de la qualité du lait etles 5 composantes de la performance environnementale analysées, seule la composante santé de la qualité du laitprésente des différences significatives entre les différents types de fermes. Une corrélation significative et positiveest établie entre risque d’eutrophisation et risque pour la santé. D’autres corrélations en tendance sont analyséesentre les composantes de la qualité du lait et de la performance environnementale, en association avec les pratiquesagronomiques.

Séance : Economie; International audience

Séance : Alimentation; International audience; To study the interactions between the plant biodiversity of pastures, ruminants, their microbiota and their products, an in vivo and in vitro experiment was carried out in the spring 2018. After a 5-week adaptation period on a common plot, 2 groups of 7 dairy cows were led for 4 weeks on 2 plots with contrasting levels of plant biodiversity: LD (19 species, mainly grasses) and HD (56 species, mostly dicots). Samples of grass selected by the cows (simulated bites), rumen fluid, faeces, and milk were taken at the end of the experimental periods, respectively. Milk production and protein and fat concentration were similar between treatments. The grass from group HD was more fibrous and had a higher total tannin content. Grass total fatty acids (FA) and C18:3 n-3 contents were higher for LD. Total gas production during in vitro ruminal fermentation of HD grass was lower compared to LD, this being probably due to the inhibition of bacterial proliferation by tannins, which also protected the digestion of the dry matter of the HD group compared to LD. Ruminal fluid of HD cows differed from that of LD cows by a lower concentration of total FA but a higher proportion of polyunsaturated fatty acids (PUFA). This suggests a less complete biohydrogenation of dietary PUFA induced by tannins. The β-diversity, which considers the equipartition of species, showed differences between the bacterial and fungal communities of the ruminal liquid and the faeces of the cows between the 2 treatments. The FA profile of milk from LD cows is distinguished by a higher concentration of C18:2 c9t11. Moreover, the quantity of C18:3 n-3 is not significantly different between the treatments, despite the marked differences on grass. The lower total FA and n-3 content of the grass from the HD group could have been compensated by the protective role of tannins in the rumen.; Pour étudier les interactions entre la biodiversité végétale des prairies, les ruminants, leur microbiote et leurs produits, des expérimentations in vivo et in vitro ont été menées au printemps 2018. Après une période d’adaptation de 5 semaines sur une parcelle commune, 2 lots de 7 vaches laitières ont été conduits pendant 4 semaines sur 2 parcelles présentant des niveaux de biodiversité végétale contrastés : LD (diversité flaible,19 espèces, beaucoup des graminées) et HD (diversité élevée 56 espèces, beaucoup des dicotylédones). Des prélèvements d’herbe sélectionnés par les vaches (bouchées simulées), de liquide ruminal, de fèces et de lait ont été réalisés en fin de période d’adaptation, et en fin de période expérimentale. La production laitière et les taux protéique et butyreux était similaires entre les lots. L'herbe du lot HD était plus fibreuse et avait une teneur en tanins totaux plus élevée. La teneur en acides gras (AG) totaux de l’herbe, et en C18:3 n3, était plus élevée pour LD. La production totale de gaz lors de la fermentation ruminale in vitro de l’herbe HD était plus faible par rapport à LD, ceci étant probablement dû à l’inhibition de l’activité bactérienne par les tanins, qui ont également protégé la digestion de la matière sèche (MS) du lot HD par rapport au lot LD. Le liquide ruminal des vaches HD a présenté une concentration plus faible en AG totaux mais une proportion plus élevée en acides gras polyinsaturés (AGPI). Cela suggère une biohydrogénation moins complète des AGPI alimentaires induite par les tanins. La β-diversité, qui considère l’équipartition des espèces, a montré des différences entre des communautés bactériennes et fongiques du liquide ruminal et des fèces des vaches entre les 2 lots. Le profil en AG du lait des vaches LD se distingue par une concentration plus importante en C18:2 c9t11. Par contre, la quantité de C18:3 n-3 n’est pas significativement différente entre les lots, malgré les différences marquées sur l’herbe. Le contenu en AG totaux et en n-3 plus faible de l’herbe du lot HD, pourrait avoir été compensé par l’effet protecteur des tanins dans le rumen.

Séance : Bien-être animal; International audience; Animal behaviour is very sensitive to any external disturbance or change in the animal internal state. We sought to predict and classify a wide range of health, stress and physiological states from daily activity of dairy cow. We had six datasets (total, 122,000 cows*days). The caretakers noted the condition of the cows: illness, oestrus, calving, disturbances (handling, mixing. Cows were equipped with sensors to estimate the duration of activities - eating, resting, in the alleys - from which the activity level was calculated. We modelled the rhythm of activity by the Fourier transform (Harmonics 0 and 1). If the difference between the models obtained during 2 series of 24 h is higher than a certain threshold, there is a strong chance that a particular event has occurred: illness, stress, heat, farrowing. The change takes place before the caretakers spot the event. Next, we applied random forest to attributes describing the 24 h activity series (minimum, maximum, average, autocorrelations...). We correctly classify 99% of the control series (= very rare false positive) and in an episode surrounding a disease or a reproductive event, the probability of correctly classifying at least one series varies from 94 to 100%. Machine learning applied to time series seems therefore a very powerful tool to analyse the behaviour of animals and diagnose its internal state.; Le comportement d’un individu est très sensible à toute perturbation extérieure ou modification de l’état interne. Nous avons cherché à prédire et à classer un large éventail d'états de santé, de stress et d'états physiologiques à partir de l'activité quotidienne de vaches laitières. Nous disposions de six jeux de données (au total 122 000 vaches*jours). Les soigneurs notaient l'état des vaches : maladie, oestrus, vêlage, perturbations (manipulations, mélange). Les vaches étaient équipées de capteurs permettant d’estimer la durée des activités - manger, se reposer, dans les couloirs – à partir desquelles était calculé le niveau d’activité. Nous avons modélisé le rythme d’activité par des transformées de Fourier (Harmoniques 0 et 1). Si l’écart entre les modèles obtenus au cours de 2 séries de 24 h est supérieur à un certain seuil, il y a de fortes chances qu’un événement particulier soit survenu : maladie, stress, chaleurs, mise-bas. Le changement s’opère avant que les soigneurs repèrent l’évènement. Ensuite, nous avons appliqué le random forest à des attributs décrivant les séries d’activité de 24 h (minimum, maximum, moyenne, autocorrélations…). Nous classons correctement 99% des séries témoins (= quasiment pas de fausse alertes) et dans un épisode qui entoure une maladie ou un événement reproductif, la probabilité de classer correctement au moins une série varie de 94 à 100%. L'apprentissage automatique appliqué à des séries temporelles semble donc un outil très puissant pour analyser le comportement des animaux et diagnostiquer son état interne.

International audience; In many species, prenatal maternal stress leads to long-lasting changes in physiological and behavioural individual characteristics. However, these prenatal effects can be modulated by the postnatal environ-ment and especially by maternal care. The impact of maternal care on the modulation of prenatal maternal stress effects has been investigated mainly in mammalian models but, surprisingly, remains little explored in avian species. In this study, we determined the extent to which the subsequent effects of prenatal maternal stress on offspring growth and emotional responses are modulated by the presence of an adoptive mother during postnatal development using a precocial bird, the Japanese quail, Coturnix coturnix japonica , as our study species. All experimental quail chicks were the offspring of females that experienced an environmental stressor induced by a socially unstable environment during laying and egg production. Previous reports showed that social instability of laying quail increased their offspring's emotional reactivity and that this was related to an increase in yolk testosterone levels in their eggs. In this study, offspring hatched from socially unstable females were raised either with or without adoptive mothers. We found that mothered chicks were lighter during their first 3 weeks of age and that their emotional reactivity was lower (i.e. as shown by increased exploratory behaviours in a novel environ-ment, decreased neophobic responses in the home cage and decreased responses to social separation) relative to nonmothered chicks. Thus, our results highlight that maternal care could counteract the phenotypic consequences of prenatally stress-exposed birds. Our results clearly highlight that even in precocial species the presence of the mother has a fundamental importance in modulating the effects of prenatal conditions on the ontogeny of offspring behaviour and that this might be a key mechanism driving phenotypic plasticity in wild populations.

International audience; CONTEXTSo far, digital technology development in agriculture has mainly dealt with precision agriculture, often associated with conventional large-scale systems. The emergence of digital agriculture - based on the triptych of “new data sources / new processing methods / new inter-connection capacities (internet)” - opens up prospects for mobilizing digital technologies to accelerate the deployment of other forms of agriculture, such as agroecology. A specific research agenda must therefore be built to redirect researchers specialized in digital technologies towards these new issues. This construction is significant because digital technology and agroecology are disruptive innovations that shake up the actors' practices, agricultural innovation ecosystems, and value chains.OBJECTIVEAn interdisciplinary group of INRAE researchers (covering 10 scientific departments) was mandated to carry out this reflection, with the objective of developing a research agenda to better couple digitalization and agroecology, in order to pave the way for responsible digital farming. The group used the framework of responsible research and innovation.METHODOver 18 months, the group met monthly by video-conference, to overcome the interdisciplinarity barrier, and at three face-to-face seminars, where creative design exercises were carried out (based on a world café format, and “remember the future” method). This work gave rise to three prospective lines of research aimed at putting digitalization at the service of agroecology and local food systems. These topics prioritize research that fosters innovations in digital technology, as well as organisations and policies that (1) accelerate the agroecological transition on the farm and in the territories, (2) manage the territories as commons, (3) empower farmers and consumers. Then, the group examined these three prospective lines of research from an RRI perspective as well as three current research topics on digital agriculture (digital soil mapping, precision agriculture, technologies for food wastage reduction).RESULTS AND CONCLUSIONSThis work allowed us to highlight the gaps between current research on digital agriculture and the RRI expectations, and the tensions (between rationalization and diversity of farming systems, between complexity of agroecological systems and the need for simplification of models, and finally between data speculation and frugality). We were also able to refine the specific scientific questions of each prospective line of research and finally to draw attention to the key levers that will have to be integrated if these research efforts are to be approached from an RRI perspective.SIGNIFICANCEThis contribution shows RRI can be used not only to reflect on research practices but also as a framework to build a research agenda paving the way for responsible digital agriculture.

Essential fatty acids (EFA) and conjugated linoleic acids (CLA) are unsaturated fatty acids with immune-modulatory effects, yet their synergistic effect is poorly understood in dairy cows. This study aimed at identifying differentially abundant proteins (DAP) and their associated pathways in dairy cows supplied with a combination of EFA and CLA during the transition from antepartum (AP) to early postpartum (PP). Sixteen Holstein cows were abomasally infused with coconut oil as a control (CTRL) or a mixture of EFA (linseed + safflower oil) and CLA (Lutalin, BASF) (EFA + CLA) from − 63 to + 63 days relative to parturition. Label-free quantitative proteomics was performed on plasma samples collected at days − 21, + 1, + 28, and + 63. During the transition time, DAP, consisting of a cluster of apolipoproteins (APO), including APOE, APOH, and APOB, along with a cluster of immune-related proteins, were related to complement and coagulation cascades, inflammatory response, and cholesterol metabolism. In response to EFA + CLA, specific APO comprising APOC3, APOA1, APOA4, and APOC4 were increased in a time-dependent manner; they were linked to triglyceride-enriched lipoprotein metabolisms and immune function. Altogether, these results provide new insights into metabolic and immune adaptation and crosstalk between them in transition dairy cows divergent in EFA + CLA status.

International audience; In sheep, the bond between the dam and her lambs is established during the first hours of a lamb's life. Genetic variability for behavioural reactivity of ewes assessed in an arena test performed 24 hr after lambing has already been reported. However, there is no evidence that this reactivity represents the ewe's maternal reactivity at lambing in outdoor conditions. The objective of this study was to investigate whether or not the behavioural reactivity of ewes in the arena test is genetically related to their maternal reactivity measured at lambing. A total of 935 Romane ewes were studied. The maternal reactivity of ewes at the outdoor lambing site was recorded in response to a human approach and to the handling of the lambs. Their behavioural reactivity was also recorded 24 hr post-lambing in the arena test that involved a separation from the litter and a human presence. Flight distance, aggressive reaction, time to restore contact with the litter, maternal behaviour scores and vocalizations recorded at the lambing site were heritable (0.12-0.34). All of these behaviours were genetically correlated with the behavioural reactivity in the arena test. The highest genetic correlations (from 0.60 to 0.90) were found amongst maternal behavioural scores, flight distance and high-pitched bleats. In conclusion, behavioural reactivity in the arena test can be used to assess early maternal reactivity in standardized conditions. Phenotyping of ewes' behavioural reactivity with a simplified arena test can be performed for genetic improvement in maternal behaviour in sheep.

International audience; Drug-resistant parasites threaten livestock production. Breeding more resistant hosts could be a sustainable control strategy. Environmental variation linked to animal management practices or to parasite species turnover across farms may however alter the expression of genetic potential. We created sheep lines with high or low resistance to Haemonchus contortus and achieved significant divergence on both phenotypic and genetic scales. We exposed both lines to chronic stress or to the infection by another parasite Trichostrongylus colubriformis, to test for genotype-by-environment and genotype-by-parasite species interactions respectively. Between-line divergence remained significant following chronic stress exposure although between-family variation was found. Significant genotype-by-parasite interaction was found although H. contortus-resistant lambs remained more resistant against T. colubriformis. Growth curves were not altered by the selection process although resistant lambs were lighter after the second round of divergence, before any infection took place. Breeding for resistance is a sustainable strategy but allowance needs to be made for environmental perturbations and worm species.

This study explored plasma biomarkers and metabolic pathways underlying feed efficiency measured as residual feed intake (RFI) in Charolais heifers. A total of 48 RFI extreme individuals (High-RFI, n = 24; Low-RFI, n = 24) were selected from a population of 142 heifers for classical plasma metabolite and hormone quantification and plasma metabolomic profiling through untargeted LC-MS. Most efficient heifers (Low-RFI) had greater (P = 0.03) plasma concentrations of IGF-1 and tended to have (P = 0.06) a lower back fat depth compared to least efficient heifers. However, no changes were noted (P ≥ 0.10) for plasma concentrations of glucose, insulin, non-esterified fatty acids, β-hydroxybutyrate and urea. The plasma metabolomic dataset comprised 3,457 ions with none significantly differing between RFI classes after false discovery rate correction (FDR > 0.10). Among the 101 ions having a raw P < 0.05 for the RFI effect, 13 were putatively annotated by using internal databases and 6 compounds were further confirmed with standards. Metabolic pathway analysis from these 6 confirmed compounds revealed that the branched chain amino acid metabolism was significantly (FDR < 0.05) impacted by the RFI classes. Our results confirmed for the first time in beef heifers previous findings obtained in male beef cattle and pointing to changes in branched-chain amino acids metabolism along with that of body composition as biological mechanisms related to RFI. Further studies are warranted to ascertain whether there is a cause-and-effect relationship between these mechanisms and RFI.

Session 1. Protein and energy metabolism in ruminantsAbstract N.O15; International audience

International audience; In a context of increasing societal concerns around animal production, consumers asks for products coming from grazing dairy systems and. The segmentation of collection rounds to offer milk specifically from these systems results in higher seasonal variability in milk composition that needs to be better understood. Our objective was to characterize the monthly variation of milk and plasma mineral composition and heat stability, in a factorial arrangement of two breeds of cow and three grazing systems. The experiment involved 48 cows, half Holstein-Friesian (HF) and half F1 Jersey Holstein-Friesian crossbred (JFX) at Teagasc Moorepark. The grazing systems were based on either a monoculture of perennial ryegrass, or a perennial ryegrass and white clover sward, or a multispecies pasture. Milk, blood and pasture were sampled monthly between April and June 2021. Milk heat stability increased constantly between April and June and was unaffected by either the breed or the grazing system. Milk Ca, P, Zn and citrate contents were higher with JFX compared with HF, whereas that of Cl was lower. Milk soluble Ca and P contents were unaffected by the breed. Milk contents of a large part of elements (Ca, P, Mg, K, Fe, Cu, Zn, Mn), except Na and Cl, varied strongly according to the month and differently according to the considered element in interaction with the grazing system. No dominant parameters, among those prone to affect milk heat stability, could be clearly related to milk stability results. Plasma contents of all mineral elements, except Fe, strongly increased between April and June, in interaction with the grazing system for inorganic P, Mg and Zn. An important part of this variability could be related to herbage mineral content although plasma mineral contents were not clearly related to milk mineral contents. Funding by SmartCow project (H2020 N°730924) is acknowledged.

International audience

The rumen harbours countless bacteria, archaea, ciliated protozoa, fungi and viruses: various microorganisms that have established multiplicity of relationships to efficiently digest complex plant fibres and polysaccharides to produce volatile fatty acids (VFAs), microbial proteins and vitamins, essentials for the host’s health, growth and performances. Recent studies using omics-based techniques have revealed that changes in rumen microbiota are associated with changes in ruminants’ production and health parameters such as feed efficiency, methane yield, milk composition and ruminal acidity. However, traditionally, rumen microbes were unveiled using anaerobic culture-based techniques, which are at the origin of most of the basic concepts and understanding of the rumen functioning. Isolating and culturing microbes is frequently more difficult and time-consuming and requires more training than molecular techniques, which explains why culture seems to be abandoned in favour of sequencing. Microbial cultures enable the study of substrate preferences and product output, essential growth requirements, biocide production and susceptibilities; obtaining a pure culture also enables genome sequencing of these strains. We propose here, after a brief report of published rumen isolates, a comprehensive review of current advances in molecular methods to identify novel rumen microbes and discuss how culturing and mathematics could enhance our understanding of rumen microbiology.

International audience

International audience; Nutritional strategies, including feed management measures, are promising methods for CH4 and overall GHG reduction. Evidence from literature is reviewed in this article in relation to the effects of forage quality (digestible organic matter, DOM) and forage type (grasses vs. legumes, and maize). The major determinants of forage quality are botanical composition and phenological stage, i.e., at advanced growth stages of plants, the fibre content increases while DOM decreases. Methane yield (g/kg DMI) decreases with increased digestibility of forages in both dairy cattle and sheep, and also CH4 intensity (g/kg milk) decreases with increased digestibility of forages for dairy cattle. Using forage legumes in ruminant feeding systems can reduce overall GHG emissions due to decreased N fertilizer use and related emissions. Recommended dietary mitigation measures are often related to a reduction in N excretion such as better matching of dietary protein to animal needs, shifting N excretion from urine to faeces (by tannin inclusion at low levels) and reducing the amount of excreted fermentable organic matter. Methane decreases with increasing intake of forage legumes rich in tannins and there is a shift of N partition from urinary N towards faecal N. Reduced CH4 emissions from ruminants fed on forage-based diets will decrease the carbon footprint of livestock and agriculture and improve the efficiency of productive ruminants in both developing and developed countries. Likewise, estimations of net CH4 output should account for enteric CH4 emissions and soil carbon (C) sequestration of land used for feed production (i.e., grasslands and croplands).

International audience; Herbivore farming systems in the Auvergne region (north of the French Massif central) are highly diverse as the result of history and strong pedoclimatic contrasts. Among agroecological principles, system diversification is assumed to increase farm economic and environmental performances, but we still lack knowledge on how to manage these systems. Here we report the result of farm surveys that were conducted across a range of systems from the same areas: beef-crop, mixed cattle-sheep and cattle-horse systems. We also use a bioeconomic optimization model to provide further information on mixed beef-dairy systems, including their carbon footprint and resilience to market hazards. Grazing two livestock species on the same farm leads to a better utilization of grasslands and can dilute parasite burden, and doing this decreases inputs and production costs.Integrated crop-livestock management also decreases feeding costs, and so production costs and farm carbon footprint. Equipment and housingcosts were reduced in mixed cattle-sheep systems, where mixed farming also buffered farm income variability. Equipment largely differ betweenthe beef and crop enterprises, which limits economies of scope in beef-crop systems. Buffer capability was reduced in mixed beef-dairy systemswhere both enterprises produce meat and thus rely on the same market. Finally, workload was more evenly distributed along the year in mixedcattle-sheep systems. Farmers also mentioned the pleasure of varied work and flexibility of work organization in mixed systems as a matter ofsatisfaction. We conclude that in spite of various amplitudes in the effects observed, the diversification of herbivore farming systems can enhancesystem efficiency and increases options for adapting to change, and that this can occur at a constant workload; Les systèmes d’élevage en Auvergne associent souvent plusieurs productions du fait de la géographie et de l’histoire régionale. Avec latransition agroécologique, la diversification des systèmes d’élevage herbivores est considérée comme un levier pour répondre à leurs enjeuxproductifs et environnementaux, mais les références techniques et organisationnelles manquent encore. Ici nous rapportons de nouvellesconnaissances issues d’enquêtes réalisées dans trois types de systèmes diversifiés : polyculture-bovins viande, mixtes bovins-ovins et mixtesbovins-équins. Un modèle d’optimisation sous contrainte étend l’analyse au système bovins lait-viande, et simule l’empreinte carbone etla résilience des différents systèmes. Conduire deux espèces animales au sein d’une même exploitation permet de mieux gérer l’herbe etle parasitisme digestif, et peut ainsi réduire les intrants et les charges variables de l’exploitation. De même, l’association de cultures à unélevage bovins viande conduit à acheter moins d’aliments, et réduit les charges variables et l’empreinte carbone de l’exploitation. La mixitébovins-ovins dilue les coûts d’équipement pour la récolte des fourrages, les besoins en bâtiments, et sécurise le revenu. Peu d’équipementssont en revanche communs aux ateliers d’élevage et de cultures ce qui limite les économies de gamme en polyculture-bovins viande. Lesfluctuations annuelles du revenu sont les moins tamponnées dans le système bovins lait-viande où les deux ateliers partagent le mêmemarché de viande bovine. Enfin, la mixité d’espèces permet de mieux répartir le travail durant la campagne annuelle, la satisfaction liéeà un travail varié étant également mise en avant par les éleveurs bovins-ovins et bovins-équins. Ainsi malgré des bénéfices d’amplitudevariable selon les systèmes, la diversification des systèmes d’élevage herbivores peut accroître leur efficience et offre des clés d’adaptationface à la variabilité du contexte de production, sans nécessairement générer plus de travail.

International audience; The ability of mid-infrared spectroscopy (MIR) to predict indicators (1) of diet composition in dairy herds and (2) for the authentication of the cow feeding restrictions included in the specification of 2 Protected Designation of Origin (PDO) cheeses (Cantal and Laguiole) was tested on 7,607 bulk milk spectra from 1,355 farms located in the Massif Central area of France. For each milk sample, the corresponding cow diet composition data were obtained through on-farm surveys. The cow diet compositions varied largely (i.e., from full grazing for extensive farming systems to corn silage-based diets, which are typical of more intensive farming systems). Partial least square regression and discriminant analysis were used to predict the proportion of different feedstuff's in the cows' diets and to authenticate the cow feeding restrictions for the PDO cheese specifications, respectively. The groups for the discriminant analysis were created by dividing the data set according to the threshold of a specific feedstuff. They were issued based on the specifications of the restriction of the PDO cheese. The pasture proportion in the cows' diets was predicted by MIR with an coefficient of determination in external validation ((RV)-V-2) 0.81 and a standard error of prediction of 11.7% dry matter. Pasture + hay, corn silage, conserved herbage, fermented forage, and total herbage proportion in the cows' diets were predicted with a (RV)-V-2 >0.61 and a standard error of prediction = 50%, and pasture >= 57% in the cows' diets achieved an accuracy and specificity >= 90%. A sensitivity and precision >= 85% were also observed for the pasture proportion discrimination models, but both of these indexes decreased at increasing thresholds from 0 to 50, and 57% pasture in the cows' diets. An accuracy >= 80% was also observed for pasture + hay >= 72%, herbage >= 50%, pasture hay >= 25%, absence of fermented herbage, absence of corn silage, and corn silage 90%. Both the regression and discriminant MIR models for bulk milk can provide useful indicators of cow diet composition and PDO cheese specifications to producers and consumers (farmers, dairy plants).

Newborn ruminants possess an underdeveloped rumen which is colonized by microorganisms acquired from adult animals and the surrounding environment. This microbial transfer can be limited in dairy systems in which newborns are separated from their dams at birth. This study explores whether the direct inoculation of fresh or autoclaved rumen fluid from adult goats to newborn kids has a beneficial effect on rumen microbial development and function., This study was funded by the Spanish Research Agency (Ref. AGL2017 86938-R) and the Training Program for Academics grant, Madrid, Spain (Ref. FPU16/01981). We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI)

International audience; The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows (½ Bos taurus – ½ Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions.

This work aims to identify the rearing practices which increase the carcase weight according to slaughter age. For this purpose, an innovative statistical method, the decision tree method, was used to identify the most influential action levers on the carcase weight, with associated thresholds values and modalities, among the rearing practices applied throughout the animals’ life. The data of 636 heifers carcases were collected from the slaughterhouse and the rearing practices from 45 farms by survey. Firstly, classifications were done to define slaughter-age classes and carcase-weight classes. Three slaughter-age classes (younger, mid-age, older) and 3 carcase-weight classes (lighter, intermediate, heavier) were defined, then these two classifications were crossed. The decision tree method highlighted that the influence on carcase weight of the life periods of the animals (i.e. suckling, growth, and finishing periods) and the related rearing practices were different according to the slaughter age of the heifers. For the younger-slaughtered animals, the most influential rearing practices on the carcase weight were the suckling duration, the concentrate supply during growing, the distributions of compound feed and grass silage in-stall during growing. For the mid-age slaughtered animals, the rearing practices identified as the most influential were the concentrate amount distributed in-stall during finishing, the meal supply in-stall during finishing and the cereals supply at pasture during growing. For the older-slaughtered animals, the compound feed supply at pasture during finishing and the concentrate amount distributed in-stall during growing were the most influential on the carcase weight.HIGHLIGHTS Decision tree: an innovative statistical method to identify action levers on carcase weight among the applied rearing practices throughout the life. The influential periods and rearing practices were distinct according to the slaughter-age of the animals.

International audience

International audience; Mid infrared (MIR) spectra have been used since the late 2000s to phenotype new traits at large scale through prediction equations. It has been used in France since 2012 to quantify free fatty acids on herd milks in the framework of quality-based milk payment system. In addition to the loss of income, a high lipolysis level leads to a degradation of organoleptic (rancid taste) and technological (processing inability) properties of milk. Monitoring lipolysis is required to maintain the quality of milk and dairy products. Lipolysis depends on many factors: genetics, farming practices, milking equipment, transformation process. Regarding genetics, Vanbergue highlighted in 2017 the existence of a genetic susceptibility to spontaneous lipolysis. The present study aims to investigate this issue further, by studying the genetic determinism of spontaneous lipolysis in a larger number of cows. This work is carried out within the framework of the LIPOMEC project which aims to better understand the molecular mechanisms controlling the degradation of milk fat. Studying the genetic determinism of lipolysis requires the phenotyping of a large number of cows. As the equation initially developed on herd milk was not fully appropriate for individual milks (range, precision), a new prediction equation was estimated from the MIR spectra of individual milks. For this purpose, 432 milk samples were collected in 4 experimental farms in 2018 (approximately 40 cows per farm sampled 2 or 3 times a year) to maximize the variability of breeds (Holstein, Normande, Montbéliarde) and diets. A joint analysis of lipolysis according ISO/TS 22113 standard (BDI method) and by MIR spectrometry was carried out on each sample. Lipolysis measured by BDI method averaged 0.53 mmol/100 g fat (sd=0.41 mmol/100 g fat). The equation was developed by Partial Least Square regression after LOG transformation. Its coefficient of determination R² reached 0.72, with a residual standard deviation Sy,x of 0.19 mmol/100 g of fat. The equation was then applied to obtain phenotypes on more than 300,000 MIR milk spectra from Holstein, Normande and Montbéliarde breeds. Genetic parameters were estimated using a repeatability animal model. Heritability and repeatability estimates were 0.21 and 0.40 in both Normande and Hostein breeds but higher (0.31 and 0.46) in Montbéliarde breed. This work opens the opportunity to new uses of MIR spectra to improve the control of lipolysis in farm, by a closer management of the herd, or even by selection. The LIPOMEC project was funded by APIS-GENE.

National audience

Data Paper; International audience; Winter soil cover by vegetation is associated with multiple benefits, such as increasing soil carbon storage and reducing erosion and nutrient leaching. This dataset provides an estimate of winter soil cover before spring-sown crops at municipality level for mainland France for two years (2018 and 2019). These estimates were obtained through the monitoring of all plots with spring-sown crops, declared within the context of the European Common Agricultural Policy. Detection of plots with winter soil cover was achieved through the analysis of Normalized Difference Vegetation Index (NDVI) time series, computed from Sentinel-2 multispectral images. For this dataset, it was considered that soil cover had to exceed 50% for a plot to be considered as covered by vegetation. Based on the literature, this corresponds to a threshold NDVI value between 0.45 and 0.59. To allow for sensitivity and uncertainty analyses for future studies that may be conducted using these data, three estimates of winter soil cover are given: minimum (based on the cultivated area exceeding the upper NDVI threshold of 0.59), maximum (considering the lower NDVI threshold of 0.45) and best estimate (mean NDVI threshold of 0.52). This dataset may be useful primarily to researchers working on biogeochemical cycle modeling or to government agencies, as several public policies (such as the Nitrates Directive) aim at developing winter cover crops.

International audience

International audience; The protein degradation of alfalfa hay after tannin supple-mentation was monitored during wethers digestion. Three rumen-cannulated wethers were infused a tannin solution, and water for control, through the cannula. The digestion time-points samples were collected in vivo in the rumen and in vitro in the abomasum, and the small intestine com-partments. The digestomic dataset was acquired by identi-fying and quantifying the peptides resulting from the pro-tein degradation, using high-resolution LC-MS/MS mass spec-trometry and label-free quantitation. The digestomic dataset is the compilation of proteomic data acquired in the rumen and peptidomic data acquired in the abomasum and in the small intestine. The proteomic analysis identified 20 Med-icago proteins in the rumen fluid, based on 169 peptides of which 140 are unique. The peptidomic analysis identified 28 Medicago proteins in the abomasum, based on 575 peptides of which 363 are unique, and 11 Medicago proteins in the small intestine, based on 94 peptides of which 63 are unique. This digestomic dataset of proteolysis during sheep post ru-men digestion after tannin supplementation reveals the pro-tein regions protected by tannin supplementation, and could be reused in studies related to the protein use efficiency by ruminants.

International audience; AbstractDespite the benefits associated with winter soil cover before sowing a spring crop, this practice is adopted unevenly by farmers. The goal of this paper is to identify and hierarchize the main soil-climate factors that hinder the adoption of cover crops. It is the first study to carry out this analysis at the scale of France, which is a country with a wide variety of soil types and climates. For this country, maps of vegetated winter soil cover prior to the establishment of a spring crop were previously produced for years 2018 and 2019, using Sentinel-2 multispectral images. For approximately half of France’s acreage with spring crops, the estimation concerning the presence or absence of a winter cover crop was correlated here with the main soil-climate factors of each field. The inclusion within Nitrate Vulnerable Zones is another potentially important variable to explain cover crop adoption, as regulatory requirements of the Nitrates Directives strongly encourage winter soil cover in these zones to reduce nitrogen losses. Because of the regulatory requirements of the Nitrates Directives regarding winter soil cover, the influence of being located in a Nitrate Vulnerable Zone was also evaluated. But despite these incentives for winter soil cover, inclusion in a Nitrate Vulnerable Zone had little influence on cover crop adoption. Principal component analyses performed for different crop rotations showed that the clay content was the soil-climate factor most negatively correlated with the adoption of cover crops. Cover crops were more frequently established on sandy fields with high organic carbon stocks, which corresponds rather to the characteristics of livestock regions. The development of technical solutions for the establishment and destruction of winter cover crops on clay soils could facilitate the adoption of these crops, and thus improve global water quality.

Ce numéro regroupe des textes issus des projets ayant travaillé dans le cadre du Programme PSDR 4, sous l’égide d’INRAE et de 10 Régions françaises.; International audience; Among agroecological principles, it has been assumed that incorporating diversity into livestock farming systems could increase their multiperformance and enhance their resilience. Technical references are however still missing. The research-development project PSDR4 New-DEAL (2015-2020) provided technical and organizational knowledge on/for multi-species grassland-based systems and integrated crop-livestock systems. Research was conducted across spatial scales, from territory to system components (animal and vegetal resources and work organization), with a focus on fodder autonomy and system resilience. Local consumers favoured buying an average basket consisting of a mixture of beef, pork and vegetable, and their willingness to pay for these products was mainly related to a territorial vitality. A strong reduction of inputs in mixed-grazing and crop-livestock systems was shown to result from enhanced crop-livestock interactions, a better utilization of grasslands and dilution of parasite burden in mixed grazing systems. Mixed herbivore systems also had enhanced buffer and adaptive capabilities, and so resilience, thanks to opportunities related to housing facilities, animal feeding management and work organization.; Dans le cadre de la transition agroécologique, la diversification des systèmes d’élevage est mise en avant par de nombreux auteurs comme un des leviers pour répondre aux enjeux productifs, environnementaux et sociaux des productions animales. Les références techniques et organisationnelles sur les élevages diversifiés manquent pourtant. Le projet PSDR4 New-DEAL (2015-2020) a produit des références à des niveaux d’analyse allant du territoire jusqu’au troupeau, afin d’accroitre la résilience et l’autonomie des élevages d’herbivores par leur diversification. Dans les deux terrains enquêtés, qui sont différents par leurs productions animales, l’intérêt des consommateurs locaux est fort pour la viande produite dans le territoire sous signe officiel de qualité ; ces consommateurs expriment une volonté de préserver l’emploi local. Dans tous les types de systèmes d’élevage diversifiés analysés, une réduction importante des intrants est envisageable grâce aux interactions cultures-élevage et à une meilleure valorisation de l’herbe en pâturage mixte, associée à une dilution de la charge parasitaire des animaux, qui permet de réduire le recours aux anthelminthiques. La mixité d’espèces animales accroit aussi les capacités d’adaptation des éleveurs dans leur gestion des pics et aléas de travail, des évolutions de politiques et des aléas de marché, rendant ainsi les systèmes d’élevage plus résilients.

One of challenges of the French dairy goat sector is to develop, promote and support the development of sustainable farming systems. French dairy goat farms are strong users of grass, used mainly in hay, butthe feeding self-sufficiency of these farms remains relatively low (on average 61%). Greater use of herb is a technical solution to respond this societal demand, reduce feeding costs and the environmental footprint. On the 2015-2020 period, a strong mobilization of Research and Development stakeholders in the PSDR4 Flèche to understand the grass use place and level in dairy goat farming systems, to determine its technical and sociological pros and obstacles, and to provide scientific and technicalknowledge. This project has made it possible to acquire new knowledge on the use of multi-species grasslands by dairy goats, their use level and the nutritional qualities of milks and cheeses. Associatedwith agricultural education, the agroecological transition of goat farms can take place to make them more sustainable, more competitive and more resilient to hazards, especially in a context of climate change; Un des enjeux de la filière caprine française est de mettre au point, promouvoir et accompagner le développement de systèmes de production plus durables. Cependant, malgré une forte utilisation del’herbe, principalement sous forme de foin, l’autonomie alimentaire des exploitations caprines françaises techniques pour répondre aux exigences sociétales en matière d’élevage, mais également pour réduirele coût alimentaire et l’empreinte environnementale. Sur la période 2015-2020, les acteurs de la recherche, du développement et de la formation se sont mobilisés dans le projet PSDR4 Flèche pourcomprendre la place et le niveau de valorisation de l’herbe dans les systèmes caprins, d’en déterminer les avantages et les freins techniques et sociologiques, et d’apporter des références scientifiques ettechniques sur son utilisation. Ce projet a ainsi permis d’acquérir de nouvelles connaissances sur l’utilisation des prairies multi-espèces par les chèvres, leur niveau de valorisation et les qualitésnutritionnelles des laits et des fromages des systèmes herbagers. Associé à l’enseignement agricole, la transition agro-écologique des élevages caprins peut s’opérer pour les rendre plus durables, compétitifset résilients aux aléas, tout particulièrement dans un contexte de changement climatique.

International audience; This paper investigates the conditional technical and managerial efficiency of European banks through the lending channel using a robust nonparametric frontier approach. We select the largest commercial banks in France, Germany, the United Kingdom, Italy, Spain, and Greece over the period 2005–2013 for our study. The estimates show significant technical inefficiency in the use of available resources for banks in our sample. The overall measure of managerial efficiency suggests sound managerial performance. However, at a detailed level, we find that, for each country examined, banks exhibit large proportions of poor managerial performance. This may explain why some banks could not resist the 2008 financial crisis. Regarding institutional factors, we find capital requirements and bank size are associated with bank efficiency in a nonlinear manner. These findings provide support for contextual factors in determining bank efficiency and rethinking financial reforms.

The lean-to-fat ratio is a major issue in the beef meat industry from both carcass and meat production perspectives. This industrial perspective has motivated meat physiologists to use transcriptomics technologies to decipher mechanisms behind fat deposition within muscle during the time course of muscle growth. However, synthetic biological information from this volume of data remains to be produced to identify mechanisms found in various breeds and rearing practices. We conducted a meta-analysis on 10 transcriptomic data sets stored in public databases, from the longissimus thoracis of five different bovine breeds divergent by age. We updated gene identifiers on the last version of the bovine genome (UCD1.2), and the 715 genes common to the 10 studies were subjected to the meta-analysis. Of the 238 genes differentially expressed (DEG), we identified a transcriptional signature of the dynamic regulation of glycolytic and oxidative metabolisms that agrees with a known shift between those two pathways from the animal puberty. We proposed some master genes of the myogenesis, namely MYOG and MAPK14, as probable regulators of the glycolytic and oxidative metabolisms. We also identified overexpressed genes related to lipid metabolism (APOE, LDLR, MXRA8, and HSP90AA1) that may contribute to the expected enhanced marbling as age increases. Lastly, we proposed a transcriptional signature related to the induction (YBX1) or repression (MAPK14, YWAH, ERBB2) of the commitment of myogenic progenitors into the adipogenic lineage. The relationships between the abundance of the identified mRNA and marbling values remain to be analyzed in a marbling biomarkers discovery perspectives.

International audience; Background: Implementation of proteomics over the last decade has been an important step toward a better understanding of the complex biological systems underlying the conversion of muscle to meat. These sophisticated analytical tools have helped to reveal the biochemical pathways involved in fresh meat colour and have identified key protein biomarkers.Scope and approach: Until recently, there have been no detailed or critical studies on the role of protein biomarkers in determining meat colour. This review presents an integromics of recent muscle proteomic studies to investigate pathways and mechanisms of beef colour. A database was created from 13 independent proteomic-based studies including data on five muscles and a list of 79 proteins which were significantly correlated with colour traits. The database was subjected to a multistep analysis including Gene Ontology annotations, pathway analysis and literature mining. This report discusses the key protein biomarkers and the biological pathways associated with fresh beef colour. Biomarkers were prioritised by the frequency of identification and the need for future validation experiments is discussed.Key findings and conclusions: This review identifies six pathways involved in beef colour including energy metabolism, heat shock and oxidative stress, myofibril structure, signalling, proteolysis and apoptosis. The data-mining of the list of the putative biomarkers showed that certain proteins, such as beta-enolase (ENO3), Peroxiredoxin 6 (PRDX6), HSP27 (HSPB1), Phosphoglucomutase 1 (PGM1), Superoxide Dismutase [Cu-Zn] (SOD1) and mu-calpain (CAPN1) were consistently reported by multiple studies as being differentially expressed and having a significant role in beef colour. This integromics work proposes a list of 27 putative biomarkers of beef colour for validation using adapted high-throughput methods.