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International audience; As part of the development of green financing for agriculture, we propose a tool for assessing the environmental impacts of farm investments. This tool could allow stakeholders (bankers and investors) to allocate loans according to the ‘green’ nature of equipment. The work presented here considers specialised dairy and pig farms but also works for crop farming. The impacts of farm equipment were assessed through the impacts of agricultural practices they allow to implement. Firstly, each practice was evaluated for eight environmental performances: soil quality, water quality, air quality, greenhouse gas emissions, energy consumption, water consumption, biodiversity and animal welfare. The notation associated to each performance was based on a qualitative five level scale corresponding to a strongly negative, negative, neutral, positive or strongly positive impact. The practices dealt with feeding and forage production, manure management, housing, herd management, milking, biodiversity management and resource use. Their impacts were evaluated based on scientific literature and expert judgement. Secondly, the pieces of equipment required to implement these practices were listed, resulting in 157 pieces of equipment for dairy farming and 91 for pig farming. When a piece of equipment was used to implement a single practice, it received the grade of the practice; when several pieces of equipment could be used to implement different practices, their impacts were evaluated through the mean value of practice impacts. The final databases gather 162 practices for dairy farming, 72 for pig farming and 248 pieces of equipment evaluated for the eight performances. When a practice or a piece of equipment has both positive and negative environmental impacts, we explain the antagonisms and identify the means of mitigating the most negative impacts.

International audience; Autophagy is a lysosomal degradation pathway with a role in the turnover of cell components via self-digestion.Over the past decade, it has been recognised as an essential process to maintain cellular and energy homeostasis. Nevertheless, little attention has been paid to this process in agronomical animal species. In pigs, the role of autophagy in skeletal muscle homeostasis and more specifically on the formation of multi-nucleated muscle fibres needs to be determined. Primary culture of satellite cells, the resident muscle stem cells, is an appropriate model to investigate macro autophagy (hereafter autophagy), the main autophagy process. The objective of the current study was to evaluate tools to monitor autophagy flux in this cell model and to determine the impact of autophagy on cell differentiation. Samples of longissimus muscle were collected from 4-day-old piglets. After isolation, satellite cells were plated in growth medium, allowed to proliferate up to 80% confluence and then placed in an appropriate culture medium for 6 days to differentiate into myotubes. Proliferating and differentiating cells were explored. Autophagy-related proteins (LC3-I, LC3-II, ULK-1, Beclin, p53, PI3K and p62) were detected by Western blotting in proliferating cells and at day 1, 3 and 6 of differentiation. The two major regulators of metabolism: mammalian target of rapamycin (mTOR), a central hub of nutrient signalling and cell growth, and AMP-activated protein kinase (AMPK), a major sensor for cell energy, were also detected. Then, cells were treated with an inhibitor of autophagy flux, bafilomycin A1 to confirm that autophagy was activated during the conversion of myoblasts into myotubes in our satellite cell culture model. In conclusion, we demonstrated that basal autophagy is required for porcine satellite cell differentiation in vitro. The next step will be to demonstrate that autophagosome biogenesis impairment halts cell fusion during stages of differentiation and the fusion step of myocytes.

International audience; Under rotational grazing systems, the residence time per paddock may vary from 1 to 10 days according to paddock size. The farmer’s decision to change a herd from one paddock to another one is not always easy. We hypothesised that recording grazing behaviour may help farmers to take decisions. The objective of this study was to determine the effect of the residence time (1, 2, 4 or 8 days per paddock) on the pattern of milk production and grazing behaviour in rotationally grazed dairy cows. Treatments were compared in a completely randomised design with 9 Holstein cows per treatment, during 72 days in spring 2018. Residence times were obtained from changing paddock size, and treatments were compared at similar levels of herbage allowance. Milk production and grazing time were recorded daily. The average milk production was similar between treatments. However, milk production and grazing time varied cyclically, with both duration and amplitude of the cycles directly proportional to the residence time. Cows never stopped grazing, even at longest residence time, with very low pasture herbage availability in the last days. It is concluded that recording of grazing behaviour is not sufficient to help farmers take grazing management decisions.

International audience; In Ireland, perennial ryegrass (Lolium perenne L., PRG) varieties are typically sown as mixtures but evaluation of variety performance takes place in monoculture plots. Two PRG variety studies were conducted to examine the performance of known varieties sown as mixtures under animal grazing. Within each study four varieties were examined. Ploidy was split equally within both studies. The first study contained varieties with a heading date range of nine days (2 June to 10 June). The second study contained varieties with a wider heading date range of eighteen days (23 May to 9 June). The studies were established in 2017 and examined over two grazing seasons. Within both studies, herbage accumulation, grazing efficiency and nutritive value ranking of mixtures differed significantly based on ploidy content. Variety mixtures tended to perform as the mean of the component varieties monoculture performance.

International audience; The objective of this study was to evaluate the impact of 3 available herbage mass strategies (HM) and 2 whole grazing intensities on the performance of spring calving dairy cows during late lactation. The 3×2 factorial design experiment was conducted in autumn over 3 years (2017, 2018 and 2019) and consisted of: Low Herbage Mass (LHM), Medium Herbage Mass (MHM) and High Herbage Mass availability (HHM) and 2 grazing intensities (GI; Medium Intensity (MI; 2.75 cows ha‑1) and High Intensity (HI; 3.25 cows ha‑1). Autumn mean pre-grazing biomass yield was 1,280, 1,731 and 2,080 kg dry matter (DM) ha‑1 for LHM, MHM and HHM, respectively resulting in post-grazing residual heights of 34.3, 36.8 and 37.3 mm, respectively. There was no difference in milk and fat plus protein yield between the 3 HM treatments during autumn (1 and 1.52 kg cow‑1 d‑1, respectively). Grazing intensity had no effect on pregrazing measurements, with the exception of daily herbage allowance which was higher (P

International audience; From a climate change perspective, grassland soils have the ability to sequester C. However, there are still uncertainties on the magnitude of C sequestration potential, and their use in climate initiatives (i.e. 4p1000). Average values (± standard error) of 0.7±0.1 Mg C ha‑1 yr‑1 for permanent grassland (PG), and 0.4 to 0.8 Mg C ha‑1 yr‑1 for grass-ley (temporary grassland, TG), have been cited by different studies, while soil inventory reports only 0.05±0.3 Mg C ha‑1 yr‑1. These discrepancies can be attributed to differences in pedo-climatic conditions, intensity and type of management, but also to age and lifetime of temporary grasslands (TG). To analyse in detail C sequestration potential of French grasslands, a national study ‘4p1000 France’ was conducted to identify (1) C ‘storing’ practices; (2) their potential to be adopted as mitigation option; and (3) their cost of implementation. Along with a literature review, a modelling approach at fine spatial-scale resolution (1 km2) was used to simulate key grassland managements for PG and TG identified from agricultural statistics. Results showed that insertion of TG gained additional +0.47 Mg C ha‑1 yr‑1, while the replacement of mowing by grazing of intensively used PGs added +0.3 Mg C ha‑1 yr‑1 to soil, compared to baseline (0.26 and 0.21 Mg C ha‑1 yr‑1 for TG and PG). C storage under baseline and mitigation practices was able to offset field-based greenhouse gas emissions over French grassland areas.

International audience; Grazing management should be adapted as required, depending on weather and grass growth. To highlight this variability between years, simulations of 6 weather years from Le Pin au Haras (2007 to 2012) was investigated using the Pasture Based Herd Dynamic Milk (PBHDM) model. A 20 hectare farm divided into 10 paddocks with 36 cows was simulated. Each year had the same grazing management rules applied, such as the date on which grazing started, i.e. when one paddock had reached a grass height 8 cm, or an objective pre-grazing height of 10 cm. The only variation in input was the weather that was impacting the grass growth, forcing the model to adapt to different situations. The main results confirm large grass growth variations between years (6.2 to 14.2 Mg ha‑1). The amount of grass intake by the cows was on average 3.1 Mg dry matter (DM)‑1 cow‑1 (2.1 to 3.5 Mg DM‑1 cow‑1) and the silage fed to the animals during the grazing season was on average 0.4 Mg DM‑1 cow‑1 (0.1 to 1.3 Mg DM‑1 cow‑1). The variation in terms of milk yield was 6.2 to 6.7 Mg cow‑1. This paper highlights the challenges faced by farmers and the importance for farmers to be capable of timely reactiveness and flexibility in a changing environment.

Eberle, U., Smetana, S., Bos, U. (Eds.); International audience; Purpose. European pig production aims at reducing its environmental impacts with various mitigation strategies. Among them, the replacement of Brazilian soybean meal (BSM) associated to deforestation with European protein sources (EPS) combined with the genetic improvement of feedefficiency was tested in the H2020 Feed-A-Gene project. The goal was to estimate the environmental impacts of pig production resulting from incorporating EPS in fattening feeds.Methods. Four EPS were examined: fine fraction of rapeseed meal, partly defatted soybean meals obtained from crushing of dehulled or non-dehulled soybeans, and protein paste extracted from biomass. Environmental impacts per ton of protein for feedstuffs and per kilogram of pig at the farm gate were estimated using life cycle assessment. Benefits were calculated by comparing each EPS scenario with a reference using BSM and traditional protein sources. Least cost formulation defined feed compositions. For current feedstuffs, prices come from four European countries for four contrasting years. Prices of BSM and EPS were considered zero respectively in reference and innovative scenarios in order to maximize their incorporation. Improved genetic was assessed thanks to the comparison of two lines respectively with low and high feed efficiency.Results and discussion. At feedstuff level, the EPS reduce climate change impact more than twice compared to BSM but other impacts could be increased as acidification, eutrophication and land occupation. At pig level, the average incorporation of BSM in the reference fattening diet was 13%. Compared to this baseline, EPS scenarios reduce climate change impacts (by 8-9% for the European soybean meal and by 3-4% for the protein paste and the fine fraction of rapeseed meal) but still with a transfer of impact to land use (increase of 13%). With an additional improved genetic, the reduction on climate change with EPS rises 12-16% and limits the increase of land occupation below 5%. Theseresults show a potential interest of EPS.Conclusions. EPS can’t be considered competitive as a replacement for BSM in the current context in which less than 5% of BSM was currently used in fattening diets due to the relative prices of protein sources. EPS seem interesting for climate change in a context economically favorable to BSM. But because of the transfer of impacts, there is a need for more macroscopic analyses to capture indirect land use effects.

International audience; Purpose. Feed production and excretion of nutrients by the animals are major sources of the environmental impacts of pig production. New communication and information technologies (NTIC) allow the development of precision feeding (PF) in pig-fattening units, which appears as a promising way to decrease environmental impacts of pig production. Therefore, we performed a life cycle assessment (LCA) of pig production with either conventional or PF applied to growing-finishing pigs.Methods. Two sources of data were involved: experiments and simulations performed using a model of pig fattening. A first experiment compared two-phase (2P) ad libitum (AdLib) feeding to ad libitum PF. A second experiment compared 2P restricted (Res) feeding to restricted PF. With the model, four feeding programs – 2P, 2PLCP (2P with low crude protein content), MP (daily multiphase group feeding) and PF – were simulated according to two feeding levels: AdLib and Res. A cradle-to-farm gate LCA was performed for each strategy, with the kg of live pig at farm gate being the functional unit. Five categories of impacts were evaluated: ILCD climate change (CC), ILCD acidification (AC), CML 2001 eutrophication (EU), CML 2001 land occupation (LO) and CED V1.8 non-renewable and fossil energy demand (CED).Results and discussion. PF slightly increased feed conversion ratio (FCR) and total feed intake compared with their reference 2P strategies, excepted in the in vivo experiment comparing PF-AdLib to 2P-AdLib. In this latter case, FCR was improved with PF. PF resulted in reduced N intake and N excreted relatively to 2P feeding in both in vivo and virtual experiments, whatever the rationing plan applied. PF always decreased AC and EU by reducing nitrogen excretion. With experimental data, CC was reduced in PFAdLib but not in PFRes compared to their respective 2P strategies. Simulated results showed a decrease in AC, EU and LO impacts, but not in CC, what is probably due to the small difference in total feed consumption between ad libitum and restrictedly-fed pigs (5 kg/pig). Conclusions. PF can reduce environmental impacts of pig production, particularly AC, EU and LO. Nevertheless, the definition of constraints on amino-acid and crude-protein contents and feed formulation should be made in accordance with local practices (i.e., feeding level) in order to obtain environmental gains expected with PF.

Selection is very important for the egg production domain, which is a growing market worldwide. This market has a very segmented nature, with every country having special specifications, depending on consumers expectations. This means that breeding companies have to produce birds which are adapted, or adaptable, to various breeding conditions, while still being able to produce eggs suitable for consumers expectations. Egg production market is also a very competitive, detained worldwide by only 3 enterprise groups. This means that the selection of the different lines, which are dedicated to fulfill differents production criteria, is a critical step. The genetic progress of selected populations is distributed worldwide, and optimize it is a way to stand out from the competitors.For the last few years, genomic selection is put in place in different sectors. Among other things, this methodology allowed to improve genetic progress in cattle industry, which was a precursor in the utilisation of it. This evaluation methode seems highly promising for the avian sector. To precisely estimate the effect of using it, it is necessary to know the accuracy of genomic evaluation. The main objective of this work is to estimate the precision of genomic evaluation on layers egg quality traits under different scenarios, in comparison with what is observed when using genetic evaluation., La sélection est particulièrement importante pour le domaine de la production d’œufs, qui est un marché en expansion au niveau mondial. Celui-ci présente une forte segmentation du marché, c'est à dire que chaque pays aura un cahier des charges particulier, dépendant des attentes des consommateurs. Cela signifie que les entreprises de sélection ont à produire des individus adaptés, ou adaptable, aux conditions d'élevage diverses, ainsi que capables de répondre aux différents besoin des consommateurs. C’est également un secteur fortement concurrentiel, détenu au niveau mondial par 3 grands groupes. Cela fait de la sélection des différentes lignées, qui répondent aux différents critères de production, une étape particulièrement critique. Le progrès génétique des populations sélectionnées est fortement diffusé partout dans le monde, et l'optimiser est un moyen de se distinguer des concurrents. Depuis plusieurs années, la méthodologie de la sélection génomique est mise en place dans différentes filières. Elle a notamment permis d'accélérer le progrès génétique dans la filière bovine, qui a été pionnière dans son utilisation. Cette méthode d'évaluation a été jugée prometteuse pour la filière avicole. Pour estimer précisément l'effet de l'usage de cette méthode d'évaluation sur leprogrès génétique des populations sélectionnées, il est nécessaire de connaître la précision de l'évaluation génomique. L'objectif premier de cette thèse est d'estimer la précision de l'évaluation génomique sur les caractères de qualité d’œuf chez la poule pondeuse dans différents cas de figures, en comparaisonde celle obtenue par l’évaluation génétique utilisée jusqu’alors.

International audience; Grazing time (GT) is one component of grass intake and varies with animal and sward characteristics. The objective of this experiment was to describe the effect of breed (Holstein vs Normande) and parity (primiparous vs multiparous) on grazing time within simplified rotational grazing systems. Two groupsof cows corresponding to two long-term feeding strategies grazed separately. One group (High – H) received 4 kg d‑1 of concentrate while the other (Low – L) received no supplement. Daily grazing time was measured with Lifecorder technology on 30 dairy cows (15 H and 15 L) during 5 grazing sequences (2 H and 3 L) varying between 7 and 13 days of paddock residence depending on grass availability. On average, the daily paddock access time was 1,155 min and grazing time was 530 min. Parity had no significant effect on GT. Holstein cows grazed for an additional 27 min compared with Normande cows. Grazing time was reduced with concentrate allocation, by 10 min for each 1 kg of concentrate intake. Within a paddock, the GT varied with a regular increase during the residency period. This experiment confirms the large variation in GT between cows and also with the grazing conditions.

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International audience; Seasonal pasture-based systems of milk production offer advantages such as the ability to match herd demand with grass growth and supply. Such a system can pose challenges such as increased labour input, particularly during the calving season. Once-a-day (OAD) milking, even for a short period of time at the start of lactation, may provide a solution. This experiment investigated the effects of twice-a-day (TAD) milking compared to OAD for four, six or eight-weeks at the start of lactation. Once each OAD period finished cows returned to TAD milking for the remainder of lactation. Sixty dairy-breed cows were randomised and assigned to treatments as they calved. Milk yield was recorded daily and milk composition weekly. During the first four weeks of lactation daily milk yield of TAD cows was 22% greater than the OAD herds (20.9 kg cow‑1 day‑1). Following 35 weeks the six- and eight-week OAD herds had a lower cumulative milk yield (4,864 kg cow‑1) compared with the TAD cows (5,300 kg cow‑1); there were no differences between any of the other treatments. There was no significant difference in yield of milk fat + protein between treatments (401 kg cow‑1) at the end of lactation. The results of this studyindicate that OAD milking for up to eight weeks, in early lactation does not reduce total lactation yield of milk fat plus milk protein.

BackgroundIn France, the use of obesity surgery is increasing sharply. Yet effective on severe obesity and its comorbidities, it exposes to the risk of serious postoperative complications, including nutritional issues. We aimed to synthesize the research-based evidence concerning these nutritional complications: prevalence, risk factors, recommendations on their treatment and prevention.MethodsWe carried out a PRISMA systematic review, the articles included were analyzed into a synoptic table, allowing the development of summary tables.ResultsPostoperative nutritional deficiencies are frequent (vitamin D 25-100%, B12 7-70%, iron 7-63%). A lifelong micronutrient supplementation is essential (multivitamin and minerals, vitamin D-calcium, iron, vitamin B12) to prevent the hematological, neurological, or musculoskeletal consequences of deficiencies. Their prevention-screening-treatment are part of a global postoperative management which must be multimodal and interdisciplinary. Severe malnutrition exists (, Contexte Bien qu’indiquée pour améliorer les comorbidités de l’obésité, la chirurgie de l’obésité, en forte augmentation, expose au risque de complications postopératoires, notamment nutritionnelles. Notre objectif a été de synthétiser les données de la littérature concernant ces complications nutritionnelles :prévalence, facteurs de risque, recommandations sur leurs traitement et prévention.MéthodeNous avons conduit cette revue systématique de la littérature selon la méthode PRISMA, les articles inclus ont été analysés en tableau synoptique, permettant l’élaboration de tableaux de synthèse.RésultatsLes déficits nutritionnels sont fréquents après chirurgie de l’obésité (vitamine D25–100 %, B12 7–70 %, fer 7–63 %), imposant une supplémentation en micronutriments (complexes multivitamines-minéraux, vitamine D-calcium, fer, B12), pour en prévenir les conséquences hématologiques, neurologiques ou musculosquelettiques. Leurs prévention-dépistage-correction s’intègrent dans une prise en charge multimodale et interdisciplinaire. Les dénutritions sévères ou « catastrophes nutritionnelles » existent (

International audience; Several studies led us to think that it is urgent to better equip teachers of general education to talk about livestock farming in class. One of the teachers’ requests was to succeed in making this topic more attractive for secondary school students. Therefore, we decided to develop serious games to talk about animal husbandry in class. We thought interesting to ask students from the agricultural sector to create these games: this way, young future breeders will talk and explain their job to young people from the general society. With the support of the French Ministry of Agriculture, we organised a competition to create serious games on animal husbandry. Students from agricultural secondary and advanced level schools had 5 months to produce a serious game to explain what livestock farming is all about. Twenty-five teams of various ages (from 13 to 21 years old on average) participated to the competition. Among the four themes proposed, the one on ‘livestock farming and environment’ was one of the most dealt with by the teams: it is a sign that the future breeders have understood the challenge around this subject and wanted to discuss it. The format of the game to be created was free, but most of the 25 games were board games accompanied by quiz cards. The jury was particularly vigilant regarding the technical level of the questions, the vocabulary chosen, and the support provided to the teachers, as the aim was above all to create games intended for the general public. This was the most complicated part for the competitors, who often misunderstood the knowledge gap between them and the general society. The games selected by the jury will then be corrected and validated, in order to be put up on the website www.ressources-elevages.fr, which was built specifically to provide tools for teachers wishing to talk about animal husbandry in their classrooms.

International audience; Incorporating white clover (Trifolium repens L.) into grass swards can increase milk production. Data from a four-year (2013 to 2016) grazing systems experiment with three treatments were compiled. The three treatments were grass-only receiving 250 kg N ha‑1 yr‑1 (Grass250), grass-white clover receiving 250 and 150 kg N ha‑1 yr‑1 (Clover250 and Clover150, respectively). Individual dairy cow dry matter intake (DMI) was measured in May and September each year, and in July in 2014, 2015 and 2016, using the n-alkane technique. Milk yield was measured daily during the same periods, and the milk yield potential (MYpot) and Unité Fourragère Lait (UFL) balance were calculated. The effect of parity, MYpot and body weight on herbage DMI, milk yield and UFL balance was examined. There was no effect of treatment on herbage DMI (16.9 kg), milk yield was greater (P

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International audience; Once a day (OAD) milking is growing as a strategy to manage dairy cows in Ireland. While twice a day milking is the standard milking frequency, many farmers have grown herd size, but the lack of skilled labour and increased seasonal workload has made OAD milking a viable option for a proportion of dairy farmers in Ireland. A study was set up in spring 2019 at Teagasc Moorepark, 85 spring calving cows were blocked on calving date, lactation number, previous lactation milk yield, bodyweight and pre calving body condition score. They were assigned to one of five treatments (n=17), twice a day milking (TAD), once a day for 2, 4 and 6 weeks directly post calving and full time OAD. The comparative milk production differences for 210 days into lactation show the TAD cows produced 5,198 kg milk with milk fat 45.3 g kg‑1 and milk protein 34.7 g kg‑1, the OAD herd produced 3,960 kg milk, milk fat 52.7 g kg‑1 and milk protein 37.3 g kg‑1, respectively. The level of concentrate offered to the herd was approximately 360 kg per cow. The results of this study show that OAD milking frequency is a realistic option for many farmers providing that grazing and livestock management levels are maintained at a high level.

In grazing systems, a great utilisation rate of grasslands occurs when management practices allow animals to consume a large proportion of the grass produced. Grass production can vary greatly depending on pedoclimatic conditions, grassland type, and agricultural practices (e.g., fertilisation, amendment, irrigation). A high utilisation rate is primarily achieved thanks to a low post-grazing sward height (i.e., grazing intensity is severe), although overgrazing should be avoided. The slight decrease in milk yield per animal that occurs under severe grazing conditions is more than made up for by greater annual milk yield per hectare. Several grassland or livestock indicators exist to gauge grazing severity following each grazing rotation in a given paddock. Grazing severity is largely independent of grazing management strategy (e.g., grazing system, grazing rotation duration, paddocks number), which, from a practical perspective, rarely intrinsically affects milk yield and grassland utilisation rate. On the contrary, the grassland utilisation rate may differ by between 1 t DM/ha/year (short grazing season) and 3 t DM/ha/year (long grazing season) based on whether grazing is lax (i.e., seeks to maximise individual intake) or severe (i.e., seeks to maximise intake per hectare). Recent results from commercial farms have shown that grassland utilisation rates range between 4 and 13 t DM/ha/year, depending on the paddock, in each of the French regions studied (east, centre, west)., En systèmes pâturés, une bonne valorisation des prairies consiste principalement à permettre aux animaux de récolter une fraction importante de l’herbe qui a été produite, sachant que la quantité d’herbe produite varie dans des conditions très importantes selon le contexte pédo-climatique, le type de prairies et les pratiques agronomiques appliquées (fertilisation, amendement, irrigation). Bien valoriser, c’est globalement faire pâturer les animaux assez ras, avec un pâturage dit « sévère », mais sans sur-pâturage. La légère baisse des performances individuelles qui découle de cette pratique est plus que largement compensée sur l’année par le gain de productivité à l’hectare. De nombreux indicateurs existent, sur l’animal et sur la prairie, pour définir le degré de sévérité du pâturage à chaque passage du troupeau dans une parcelle. Ce degré de sévérité est quasiment indépendant des modes de gestion du pâturage (système de pâturage, fréquence entre passages, nombre de parcelles), qui ont intrinsèquement peu d’effet sur la production et la valorisation des prairies dans la gamme d’intérêt pratique. Entre une stratégie de gestion du pâturage « libérale » qui vise à maximiser l’ingestion par animal et une stratégie « sévère » visant à bien maîtriser les refus et à maximiser l’ingestion par hectare, des écarts de valorisation annuelle d’herbe de 1 t MS/ha (saison de pâturage courte) à 3 t MS/ha (saison de pâturage longue) sont possibles. Des études récentes dans un réseau de fermes commerciales ont montré que, dans chaque région française étudiée (Est, Centre, Ouest), la gamme de valorisation d’herbe va de 4 à 13 t MS/ha selon les parcelles.

Psychosocial chronic stress is a critical risk factor for the development of mood disorders. However, little is known about the consequences of acute stress in the context of chronic stress, and about the related brain responses. In the present study we examined the physio-behavioural effects of a supplementation with a sensory functional food ingredient (FI) containing Citrus sinensis extract (D11399, Phodé, France) in a pig psychosocial chronic stress model. Female pigs underwent a 5- to 6-week stress protocol while receiving daily the FI (FI, n = 10) or a placebo (Sham, n = 10). We performed pharmacological magnetic resonance imaging (phMRI) to study the brain responses to an acute stress (injection of Synacthen®, a synthetic ACTH-related agonist) and to the FI odour with or without previous chronic supplementation. The olfactory stimulation with the ingredient elicited higher brain responses in FI animals, demonstrating memory retrieval and habituation to the odour. Pharmacological stress with Synacthen injection resulted in an increased activity in several brain regions associated with arousal, associative learning (hippocampus) and cognition (cingulate cortex) in chronically stressed animals. This highlighted the specific impact of acute stress on the brain. These responses were alleviated in animals previously supplemented by the FI during the entire chronic stress exposure. As chronic stress establishes upon the accumulation of acute stress events, any attenuation of the brain responses to acute stress can be interpreted as a beneficial effect, suggesting that FI could be a viable treatment to help individuals coping with repeated stressful events and eventually to reduce chronic stress. This study provides additional evidence on the potential benefits of this FI, of which the long-term consequences in terms of behaviour and physiology need to be further investigated.

National audience; Au cours des 20 dernières années, les impacts des changements globaux sur l'envionnement sont devenus une préoccupation croissante dans la société et leur maîtrise un enjeu politique. Pour y faire face il est nécessaire de prédire l'évolution des écosystèmes et de proposer des modalités de gestion des territoires permettant de s'adapter aux changements et de préserver la qualité des milieux. Ceci nous a amené à renforcer nos recherches sur le temps long, des échelles spatiales plus larges et les interactions complexes entre les processus biotiques et abiotiques. Cette évolution a été renforcée par les progrès technologiques et informatiques qui ont engendré une véritable révolution dans notre capacité à caractériser les écosystèmes et leur fonctionnement. Ainsi, les 20 dernières années ont été marquées par la structuration des dispositifs d'observation et d'expérimentation dans des réseaux de sites ou des plateformes, par l'appropriation de nouvelles techniques de mesures et sources d'information et par la mise en place de projets ambitieux de modélisation interdisciplinaires.

National audience; Le potentiel laitier des ruminants repose en grande partie sur le développement du tissu mammaire à partir des cellules souches et la mise en place du phénotype sécrétoire des cellules épithéliales mammaires. Pour identifier les cellules souches du tissu mammaire et évaluer leur capacité de développement et de différenciation, leur transplantation dans la glande mammaire murine reste l'approche la plus pertinente. En effet, contrairement à des études fonctionnelles in vitro, les cellules implantées retrouvent le microenvironnement adéquat pour leur différenciation in vivo. Dans ce projet, financé par un crédit incitatif du département PHASE et GA, nous avons testé la transplantation hétérologue de tissu (ou cellules) pour caractériser les populations cellulaires du tissu mammaire bovin d'un point de vue fonctionnel. Dans un premier temps, nous avons transplanté dans la glande mammaire de souris Nude (vidée de leur ébauche épitheliale mammaire) du tissu mammaire bovin sous forme d’explants, ainsi que des cellules d’une lignée mammaire bovine. Nous avons cherché à déterminer les conditions optimales permettant un développement de structures épithéliales bovines dans la glande mammaire murine. Nous avons notamment testé différentes procédures d'implantation en vue d'obtenir un microenvironnement optimal. De cette première série d'expériences, l'observation morphologique des glandes mammaires transplantées ("whole mount") a mis en évidence une ébauche typique de développement mammaire bovin. De plus, des analyses approfondies en immunohistochimie ont révélé que ces structures étaient composées à la fois de cellules épithéliales luminales et basales. Sur la base de ces résultats, nous avons initié la deuxième phase du protocole : la transplantation de cellules mammaires bovines souches triées. En effet, l’étude du lignage épithélial mammaire chez le bovin (thèse en cours au laboratoire) a permis de caractériser plusieurs populations épithéliales de type progénitrices et souches. Notre objectif est d’évaluer leur capacité de développement et de différenciation et de statuer définitivement sur leur nature. Ces populations épithéliales ont donc été triées en cytométrie, à l’aide de marqueurs de surface spécifiques, et transplantées dans une nouvelle série de souris. Les résultats de ces transplantations seront connus début 2018. A court terme, la validation de cette technologie et les résultats obtenus grâce à ce crédit incitatif apportent une plus-value fondamentale pour notre projet ANR Robustem en cours de soumission. En effet, maitriser la technique de transplantation hétérologue pour l’analyse des cellules souches est un atout majeur dans ce projet et permet de démontrer notre capacité à mener cette recherche.

International audience; The objective of this study was to evaluate the impact of chronic heat stress (HS) on microbiota composition of gestating sows and of their female offspring. There were two environmental conditions: thermoneutral (TN; cyclic 18 to 24 °C) and HS (cyclic 28 to 34 °C). Pregnant sows were exposed to either TN (PTN; n=12) or HS (PHS; n=12) conditions from d 9 to 109 of gestation. During the finishing period, two female offspring per sow were allotted to either a growing TN (GTN; n=24) or HS (GHS; n=24) environment. All pigs were fed the same diet all throughout the experiment. From 75 to 140 d of age, GTN pigs (n=24) were in TN conditions, while GHS pigs (n=24) were in TN conditions from 75 to 81 d of age and in GHS conditions from 82 to 140 d of age. Spot faecal samples were collected on d 4 and d 105 of gestation in the sows, and on 78 and 136 d of age in the growing pigs for 16S rRNA analyses of microbiota composition. In both sows and offspring, exposure to HS increased rectal (+0.16 and +0.30 °C, respectively; P

International audience; Precision feeding (PF) of gestating sows, with the individual and daily mixing of two diets with different nutrient content was previously reported to reduce protein intake, feed costs and environmental losses compared to a conventional single diet feeding (CF). The effect of PF on sows’ feeding behaviour has not been reported yet as this strategy has mainly been studied via modelling. The objective of this study, realised within the Horizon 2020 EU Feed-a-Gene program (grant agreement no. 633531), was to compare feeding behaviour of sows in gestation fed with a PF or a CF strategy. The experimental trial included 5 successive batches of 12-18 sows, housed in groups in a room (8×8 m) equipped with two automatic feeders able to daily mix two diets for each animal. The total number of visits to the feeder per day per sow (4.9 visits/d) and the total daily time spend in the feeder (64 min/d) was not affected by parity. After 70 days of gestation, PF sows visited the feeder more often than CF sows (5.1 vs 4.1 visits/d, P

In recent years, with the use of hyperprolific sows, the reproductive performance of sows has drastically improved. Currently, on many farms, the average litter size exceeds 15 piglets at farrowing and 13 at weaning. These changes in performance have been the major drivers for the evolution of sow nutritional requirements during pregnancy and lactation. At the same time, a large amount of scientific knowledge has been generated over the past 30 years that has allowed, with the help of mathematical modelling, a holistic approach to supplying energy, amino acids and minerals to sows. The aim of this review is to describe evolutions in the approach to sow feeding over the past few decades and show how the current state of knowledge on sow nutrition can be used to develop models and decision support tools and improve feeding strategies in practice. Examples are given to illustrate how using such tools can help optimize the productivity of sows. Until recently, maximizing reproductive performance of sows and their litters has been the main objective considered when defining nutritional supplies. Currently, new objectives related to the increasing societal concern for animal welfare and the environment have become the priority. This will play a major role in the future evolution of pig farming systems and the management and feeding of sows, which calls for new scientific knowledge and development of new technologies, especially those from the digital area., Ces dernières années, avec le développement de l'utilisation de truies hyperprolifiques, les performances de reproduction se sont considérablement améliorées dans les élevages. De nos jours, dans de nombreuses exploitations, la taille moyenne des portées dépasse ainsi 15 porcelets à la mise-bas et 13 au sevrage. Cette amélioration des performances a été l’un des principaux moteurs de l'évolution des besoins nutritionnels des truies gestantes et allaitantes. Dans le même temps, de nombreuses connaissances scientifiques ont été produites permettant, à l'aide de la modélisation mathématique, une approche holistique du raisonnement des apports en énergie, en acides aminés et en minéraux. L'objectif de cette synthèse est à la fois de décrire ces évolutions et de montrer comment l'état actuel des connaissances sur la nutrition des truies peut être utilisé pour développer des modèles et des outils d'aide à la décision, et ainsi améliorer les stratégies d'alimentation dans les élevages. Différents exemples sont présentés pour illustrer comment l'utilisation de tels outils peut aider à optimiser la productivité des truies, en particulier dans le cadre du développement de l’alimentation de précision. Jusqu'à récemment, la maximisation des performances de reproduction des truies et de leurs portées a constitué le principal objectif dans la définition des apports nutritionnels. Cette situation évolue rapidement vers de nouveaux objectifs liés aux préoccupations croissantes de la société pour le bien-être animal et l'environnement qui deviennent maintenant prioritaires. Cela jouera un rôle majeur dans l'évolution future des systèmes d’élevage porcins, et de la conduite et de l’alimentation des truies, faisant appel à de nouvelles connaissances scientifiques et au développement de nouvelles technologies, en particulier celles du numérique.