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International audience; Live weight (LW) is a key and conventional indicator for monitoring and assessing overall animal performance and welfare, representing the progress through different physiological stages, while providing close indication of individual physical and health status. Measuring LW in practice is still, however, quite rare and infrequent under commercial sheep farming conditions, mainly because sessions are time-consuming, stressful either for the operator or the animals. A Walk-over-Weighing (WoW) system was tested in this experiment lasting 14 weeks (i.e. 3 weeks for acclimation and adaptation and 11 weeks for data collection). We validated its use for routine and frequent monitoring of growth rate in postweaned Merinos d’Arles ewe lambs (n = 100), reared under Mediterranean grazing conditions. The necessity for an initial adaptation period of the animals was confirmed. Also, the importance of conducting an effective data cleaning procedure of the raw database automatically collected by the WoW was corroborated. Adaptation of naive ewe lambs enabled the required voluntary passages across the weighing platform and a high volume of individual and daily data after 2–3 weeks. Close monitoring of individual growth was then possible after performing sound data cleaning. A good agreement was demonstrated between WoW LW and a reference LW value (measured with a standard static scale). At the individual level, even with the lowest number of LW values collected with WoW, it was possible to monitor variations in LW at daily intervals. The establishment of an early warning system to help farmer decision-making could therefore be possible. Our results show interesting prospects for more accurate and frequent monitoring of LW in grazing sheep without human intervention, compared to what is currently carried out on commercial farms.

Within the TechCare Project, a list of Precision Livestock Farming (PLF) tools, with potential for monitoring animal welfare in small ruminant production, was formulated in TechCare Countries. The opinions of stakeholders weretaken into account after consultations, following a multi-actor approach. The OPERA method was used to reach consensus between stakeholders. Overall, stakeholders’ opinions appear rather uniform. Regarding meat sheep, thehighest appreciated PLF tool was the automated weighing and low frequency identification (LF) system, followed by localisation (GPS) and 3-axial accelerometers, as well as new ultra-high-frequency (UHF) eartags and readers forseveral uses (e.g. water intake). The most suitable PLF tools selected for dairy sheep were environmental-air quality sensors (e.g. weather stations), followed by automated milk recording, LF and automatic weighing. As for dairy goats,in addition to those selected for dairy sheep, the new UHF eartags and readers were prioritized. Regardless of the production system, the most important traits of selected PLF tools were low cost and ease-of-use. Most stakeholdersalso expressed concerns on their ability to collect and handle the data generated from PLF tools for monitoring individual animals. TechCare (www.techcare-project.eu) receives funding from the European Union’s H2020 researchand innovation programme grant no. 862050.

Additional file 2: Table S3: Position of the top SNP based on the reference genome Rambouillet v1.0 and closest gene associated with body reserves and body reserves dynamics.

International audience; Managing reproduction of a dairy sheep flock without using hormones for oestrus induction and synchronisation is an alternative method that complies with agroecological principles, animal welfare and public health concerns. However, shifting from conventional reproductive management to a hormone-free philosophy means leaving more room for individual intraflock variability in oestrus occurrence. The success of establishing alternative hormone-free reproduction systems relies on managing the variability of ewes' individual responses, which are themselves influenced by individual characteristics. Therefore, the so-called REPROsheep model was built to study the effects of individual ewes' characteristics, such as age, body condition score (BCS) or milk yield, on individual responses, as well as the overall productive and reproductive performances of the flock. This dynamic agent-based model (ABM) represents individual reproduction and lactation processes in a hormone-free management context. Outputs at the flock level were simulated using this model. Two dynamic outputs (weekly number of ewes lambing and weekly milk yield) and two punctual outputs (total number of ewes lambing and total milk yield) were simulated. Sensitivity analysis showed that the studied outputs were affected by ewe age, pre-mating BCS and milk-yield distributions in the flock. Increasing average age or pre-mating BCS by 0.5 from a starting point of 2.5 and average milk-yield by 50 L from a starting point of 195 L appeared to increase, for one breeding season, the number of ewes lambing, the concentration of those lambing events over one period, as well as total milk yield, whereas decreasing the average value of these factors by the same amount appeared to produce the opposite effect. Management strategies favouring an optimum age and pre-mating BCS, as well as good milk yield for the individuals of the flock, may thus be a lever for optimising performance, especially lambing distribution over time. Therefore, the REPROsheep model seems relevant to determine how a management strategy (affecting flock structure in terms of age, body condition or production potential) can impact the performance of a dairy sheep flock in the context of hormone-free reproduction.

International audience; The objective of this study was to evaluate the suitability of a system based on an Inertial Measurement Unit (IMU) accelerometer to assess rams’ sexual behaviour (RSB). 12 adult males (~3.5 years old;), equipped with IMU accelerometers placed between the two shoulder blades, were used in 2 parallel pen tests. The tests were replicated 6 times during the same week and consisted in 30-min. visual observations for each ram interacting with Merinos d’Arles ewes (i.e. ratio= 1 ram per 6 ewes). The RSB was then recorded according to two categories: pre-copulatory (PRE-COP: i.e. number of Anogenital Sniffs AS, Leg Kicks LK, Emission of Sounds ES, Revolve Around the Ewes RAE, Head on the Rump HR and Flehmen Fl) and copulatory (COP: number of mounts MO) behaviours. Raw accelerometer data were analysed by an algorithm developed with the Scilab software (5.4.1,2013). Overall, our results demonstrate the ability of this device to detect some, but not all, of the evaluated PRE-COP (LK, RAE and Fl) and COP behaviours (MO). In total, for the 12 rams used during the 6 tests, 80.5% of the 1,388 COP behaviours visually recorded were automatically detected by the device. Concerning the PRE-COP behaviour, from a total of 18,232 records visually recorded, the best sensitivity was performed with the LK activity (i.e. 66%, 3,002/4,484), whereas for Fl and RAE activities, the values were 57% (32/56) and 32% (67/212), respectively. The technical performance of the device evaluated here was affected both at the inter- and intra-tests levels (depending on the ram and on the behaviour parameter to be interpreted). The absence of effectiveness in interpreting other parameters was likely related to the quality of the algorithm built rather than to the device by itself. In conclusion, our preliminary results demonstrate that some of RSB can be automatically estimated by using this kind of technology. Nevertheless, more research is required to test its effectiveness regarding other RSB and with a more significant number of rams, in other seasons, etc.

Liveweight (LW) is a key and conventional indicator for monitoring and assessing overall animal performance and welfare, representing the progress along different physiological stages, while providing close indication of individual physical and health status. Measuring LW in practice is still, however, quite rare and infrequent under commercial sheep farming conditions, mainly because sessions are time-consuming, stressful either for the operator and the animals. A Walk-over-Weighing (WoW) system, already evaluated with other breeds under different conditions, was tested in this experiment lasting 14 weeks (i.e. 3 for acclimation and adaptation and 11 for data collection). We validated its use for routine and frequent monitoring the growth rate in post-weaned Merinos d'Arles ewe lambs, reared under Mediterranean grazing conditions. Similarly to previous work, the necessity for an initial adaptation period of the animals as well as for an essential data cleaning procedure of the raw database automatically collected by the WoW, were corroborated. Adaptation of naive ewe lambs enabled the required voluntary passages across the weigh platform and a high volume of individual and daily data after 2-3 weeks. Close monitoring of individual growth was then possible after performing sound data cleanings. A strong concordance of WoW LW data with the gold standard (a standard static scale) LW reference data was demonstrated. At the individual level, even with the lowest number of LW values collected with WoW, it was possible to monitor variations in LW at daily intervals. The establishment of an early warning system to help farmer decision making could therefore be possible. Our results show interesting perspectives for more precise and frequent monitoring of LW in grazing sheep without human intervention, compared to what is currently carried out on commercial farms.

International audience; In the Middle West, in the Vakinankaratra region of Madagas-car, farms have an increasing need for fertilizers and fodder, and at the same time severe economic constraints to access mineral fertilizers and animal feed. This study shows how crop-livestock integration (CLI) has helped to alleviate part of the difficulty of access to industrial agricultural inputs and contributed to farming intensification. Surveys were con-ducted with 20 farms. Using principal component analy-ses and a classification based on thirteen variables, three structural (cultivated surface area, number of cattle, number of family labor) and ten functional (production of organic manure, purchase of organic manure, purchase of mineral fertilizers, application of organic manure, rainfed rice yield, maize yield, availability of crop residues, use of crop residues, cattle supplementation, grazing duration), five types of farms were characterized: one type of small farms with a high level of CLI, two types of medium-sized farms with a medium and low level of CLI, and two types of large farms with a medium and low level of CLI. Cattle supplementation, number of cat-tle, and grazing duration best differentiated the farms. The energy and protein feed requirements of cattle were covered on a yearly basis for all farms. Nitrogen exports by crops were compensated by inputs on farms with the highest level of CLI. In conclusion, in this context of very limited access to indus-trial inputs, producers turned to CLI strategies, on the one hand, to allocate the organic manure produced on demanding crops (rice and maize) and, on the other hand, to cover cattle feed requirements.; Dans le Moyen-Ouest de la région de Vakinankaratra à Madagascar, les exploitations agricoles ont des besoins croissants en fertilisants et en fourrages, et dans le même temps de sérieuses difficultés économiques d'accès aux engrais minéraux et aux aliments de bétail. Cette étude a montré comment l'intégration agriculture-élevage (IAE) a permis de pallier en partie la difficulté d'accès aux intrants agricoles industriels et de contribuer à l'intensification agricole. Des enquêtes auprès de 20 exploitations agricoles ont été menées. A l'aide d'ana-lyses en composantes principales et d'une classification sur la base de treize variables, trois structurelles (superficie cultivée, nombre de bovins, nombre de mains-d'oeuvre familiales) et dix fonctionnelles (production de fumure orga-nique, achat de fumure organique, achat de fertilisants minéraux, épandage de fumure organique, rendement en riz pluvial, rendement en maïs, disponibilité de résidus de cultures, valorisation de résidus de cultures, complémentation de l'alimentation des bovins, durée de pâturage), cinq types d'exploitations ont été caractérisés : un type de petites exploitations avec un niveau d'IAE fort, deux types d'exploitations de taille moyenne avec un niveau d'IAE moyen et faible, et deux types de grandes exploitations avec un niveau d'IAE moyen et faible. La complémentation de l'alimentation des bovins, le nombre de bovins et la durée de pâturage ont le mieux discriminé les exploitations. Les besoins alimentaires énergétiques et protéiques des bovins étaient couverts à l'échelle de l'année pour toutes les exploitations. Les exportations d'azote par les cultures étaient compensées par les apports dans les exploitations au plus fort niveau d'IAE. En conclusion, dans ce contexte d'accès très limité aux intrants industriels, les producteurs se sont tournés vers des stratégies d'IAE, d'une part, pour allouer la fumure organique produite sur les cultures exigeantes (riz et maïs) et, d'autre part, pour couvrir les besoins alimentaires des animaux.

Dans les élevages laitiers de l'ouest du Burkina Faso, la production de lait est limitée par un déficit fourrager en saison sèche. Cette étude visait à évaluer la faisabilité et la potentialité des banques fourragères arbustives (BFA) pour complémenter l'alimentation des vaches laitières en saison sèche avec un fourrage de bonne valeur nutritionnelle. Un travail de coconception, d'installation et d'exploitation de BFA, composées de Leucaena leucocephala et de Morus alba, a été réalisé dans trois élevages de bovins laitiers de l'ouest du Burkina Faso. Les trois BFA ont été plantées à haute densité, avec 20 000 plants.ha-1, en juillet 2016. La croissance a été rapide durant les sept premiers mois (saison des pluies et début de saison sèche). Au jour de plantation (jp) plus sept mois, L. leucocephala mesurait 145 ± 11 cm et M. alba 143 ± 72 cm. Puis, durant la saison sèche, la croissance s'est ralentie. Les caractéristiques du sol, le manque de pluies et la faible profondeur des lits de plantation expliquaient les différences de croissance observées selon les sites expérimentaux. Les attaques de termites (BFA3) et le passage du feu (BFA1) ont affecté le développement des BFA concernées sans les anéantir. La production de biomasse sur BFA2 et BFA3, cumulée sur les trois coupes d'exploitation (jp+13, jp+15 et jp+17-18 mois), a été plus élevée avec L. leucocephala (8,2 ± 2,6 t MS.ha-1) qu'avec M. alba (1,8 ± 2,3 t MS.ha-1). Le coût d'installation et d'exploitation de 625 m² de BFA a été de 896 188 FCFA (environ 1350 €). Des solutions sont à trouver pour les rendre financièrement plus accessibles aux éleveurs.

International audience; The main effect of climate change on livestock production systems in the Mediterranean area is to induce changes in feed resource availability. In face of constraining and changing environmental conditions, the challenge is to find practical solutions for herd management to minimize farmer’s risk. These solutions should be good enough in terms of efficiency (E), to ensure sufficient income, and good enough in terms of resilience (R), to ensure farm sustainability. The objective of the ADAPT-HERD project is to develop simulation tools capable of evaluating the consequences of management strategies at the herd level, under contrasting and varying environments (Egypt, France, Spain and Tunisia). Our approach considers that biological adaptive capacities of small ruminants can be fully integrated within management strategies to improve R and E by: i) using reproduction practices that provide the best match between herd demand and feed supply; ii) managing groups of animals based on their adaptive capacities (targeting interventions) and iii) managing herd demography to adapt animal numbers to future feed resources. The project will implement data acquisition at animal level (fine-grained experiments on adaptive capacities and phenotyping of local breeds) and at production system level (herd management, feed resource, climate and market conditions). Data will be combined and used in computer simulations to explore different climate change scenarios and management strategies and evaluate their effects on herd R and E. Interfacing modelling tools will be a key aspect of the project, fostering knowledge exchange and collaboration, especially with ongoing projects focusing on genetic selection and breeding solutions to improve R&E in small ruminants.

International audience; In ruminants, body reserves (BR) are mobilized in situations of negative energy balance, including physiological stages with high metabolic challenges. In contrast, BR accretion occurs when nutrient requirements decrease. This dynamic is partly controlled by metabolic patterns, whereas its genetic determinism is still unknown, at least in sheep. The objective of this preliminary study was to estimate genetic parameters for a few key metabolites and hormones involved in sheep BR dynamic. The BR changes over time were monitored over three years on 318 productive Romane ewes reared exclusively in an extensive rangeland. Plasma non-esterified fatty acids (NEFA), beta-hydroxybutyrate (β-OHB) and triiodothyronine (T3) levels were quantified 2 weeks before and 3 weeks after lambing and 2 weeks before mating. Effects of physiological stage, litter size and a parity-year factor were tested to identify main sources of variation. Genetic parameters were estimated using animal mixed model considering independently measurements at each physiological stage. The least square means for NEFA, β-OHB and T3 were significantly (P

National audience; The production systems of river buffaloes (Bubalus bubalis) are receiving increasing atten- tion in the tropics. The incorporation of trees in pastures (silvopastoral systems) can improve production conditions and animal welfare. The objective of this study was to characterize the behavior of buffaloes in a silvopastoral (SP) system with Leucahena Leucocephala 600 trees per hectare and a system without trees (WT), at the heavy rain (HR) period and the light rain (LR) period in Cuba, in order to assess whether the inclusion of trees in pastures affects buffa- loes thermorregulatory behavior, the following activities were recorded observing 9 animals of 90 kg for 12 days during the daylight period, between 6:00-18:00 hours, at 10 minute intervals: grazing, ingestion from the tree leaves, rumination, water intake, walking, lying, standing, positioned in the shade of trees and wallowing. The sum of positioned in the shade of trees+ wallowing was considered as thermorregulatory behavior (TB) was diferent in both systems and season (P

National audience; Achieving the forage autonomy is a huge step in the goal of agroecological transition of farming systems. It’s a priority in the current context of climate change, economic crises and the fluctuations of prices in raw materials and concentrates used for livestock supplementation. The objective was to evaluate, under the conditions of Ariège (France) a high density mulberry (Morus alba; 25 000 plants/ha) forage production technology, previously evaluated with very good results in tropics (see references). In collaboration with a voluntary farmer, a 0.2 ha pilot paddock was planted under real life beef cattle production, after previous conventional soil preparation and early stage plant growth in a nursery phase. A monthly monitoring was scheduled during the first-establishment year (i.e. from planting in April 2017 to the first-harvest –standardization cut-, in April 2018). Afterwards, the distribution to animals started. Mulching with on-farm produced straw between rows, and manure allowed efficient weed control and organic fertilization, with a zero-input approach. The plant growth and survival, biomass yield (total and edible forage) as well as its nutritive value and cattle voluntary intake are promising. The first results in agronomic and animal performance demonstrate the feasibility of establishing this technology under temperate conditions with this fodder specie, widely distributed in Europe. However, further efforts are required and the study will continue.

The main objective of this work was to study the relationships between body reserve (BR) dynamics and rearing performance (PERF) traits in ewes from a Romane meat sheep flock managed extensively on "Causse" rangelands in the south of France. Flock records were used to generate datasets covering 14 lambing years (YR). The dataset included 1,146 ewes with 2 ages of first lambing (AGE), 3 parities (PAR) and 4 litter sizes (LS). Repeated measurements of the BW and BCS were used as indicators of BR. The ewe PERF traits recorded were indirect measurements for maternal abilities and included: prolificacy, litter weight and lamb BW at lambing and weaning, ADG at 1, 2 and 3 months after lambing and litter survival from lambing to weaning. The effects of different BW and BCS trajectories (e.g., changes in BW and BCS across the production cycle), previously been characterized in the same animals, on PERF traits were investigated. Such trajectories reflected different profiles at the intraflock level in the dynamics of BR mobilization-accretion cycles. Genetic relationships between BR and PERF traits were assessed. All the fixed variables considered (i.e., YR, AGE, PAR, LS and SEX ratio of the litter) have significant effects on the PERF traits. Similarly, BW trajectories had an effect on the PERF traits across the three PARs studied, particularly during the first cycle (PAR 1). The BCS trajectories only affected prolificacy, lamb BW at birth and litter survival. Most of the PERF traits considered here showed moderate heritabilities (0.17 to 0.23) except for prolificacy, the lamb growth rate during the third month and litter survival which showed very low heritabilities. With exception of litter survival and prolificacy, ewe PERF traits were genetically, strongly and positively correlated to BW whatever the physiological stage. A few weak genetic correlations were found between BCS and PERF traits. As illustrated by BW and BCS changes over time, favorable genetic correlations were found, even if few and moderate, between BR accretion or mobilization and PERF traits, particularly for prolificacy and litter weight at birth. In conclusion, our results show significant relationships between BR dynamics and PERF traits in ewes, which could be considered in future sheep selection programs aiming to improve robustness.

International audience; Since a few years, breeders are looking to select more robust animals in order to improve adaptation to more challenging environments. One expression of such robustness is a suitable cyclic alternation of accretion and mobilization of body reserves (BR) i.e. BR dynamics. In a previous study, we characterized several BR trajectories based on body condition score (BCS) and body weight (BW) measurements regularly recorded according to a physiological stages schedule. In addition, in a previous multi-traits approach of BR changes over time we found that BR accretion and mobilization were heritable traits and genetically linked. The objectives of the present study were therefore: (1) to evaluate the link between BR trajectories and ewes rearing performances and; (2) to estimate the genetic correlations between BR changes and ewes rearing performances. By using records from 1,146 productive Romane ewes, their rearing performances were estimated by analysing key parameters like the total weight of the litter at lambing and at weaning, and the average daily gain (ADG) of the lamb during their first, second and third month of life. The effects of the BR trajectories of the dam were also tested. Genetic correlations were estimated between the ewes’ BR changes through time and their rearing performances, by conducting animal mixed model analyses. Overall, ewes presenting a stronger decrease in their trajectories during the BR mobilization period, showed superior rearing performances. Negative favourable correlations were found between BR mobilization and the total litter weight at lambing (-0.42±0.15) and between BR mobilization and ADG of lambs during the first and second month of suckling (-0.29±0.14). Positive favourable correlations were found between BR accretion and litter weight at birth (0.42±0.15) and between BR accretion and the lamb ADG during the first month of life (0.37±0.15). Present results suggest that BR dynamics could be considered in genetic selection programs to improve animals’ resilience while enhancing ewes’ performances when facing external challenges.

L’agroécologie propose un cadre théorique pertinent pour concevoir des systèmes agricoles à la fois productifs, autosuffisants, efficients et résilients. Dans ce travail, nous questionnons dans quelle mesure, les systèmes mixtes agriculture-élevage (SMAE) les plus intégrés sont-ils aussi plus performants. Par l’analyse comparative de dix-sept études de cas issues de trois territoires tropicaux contrastés (Guadeloupe, Amazonie brésilienne, Cuba), nous appliquons l’analyse de réseaux écologiques (cf. Ecological Network Analysis, ENA) pour en caractériser l’intégration agriculture-élevage (IAE) et en évaluer les performances agroécologiques à partir d’indicateurs comme l’efficience,la productivité, le recyclage des nutriments (azote), la dépendance et la résilience. Nos résultats, issus de la reconstitution du fonctionnement des exploitations sur une année donnée, montrent que les exploitations peu intégrées sont soit peu efficientes et peu résilientes, soit peu productives et fortement résilientes. En revanche, des exploitations fortement intégrées combinent un niveau élevé de productivité, d’efficience et un bon niveau de résilience.

The main objective of this work was to study the relationships between body reserve (BR) dynamics and rearing performance (PERF) traits in ewes from a Romane meat sheep flock managed extensively on "Causse" rangelands in the south of France. Flock records were used to generate datasets covering 14 lambing years (YR). The dataset included 1,146 ewes with 2 ages of first lambing (AGE), 3 parities (PAR) and 4 litter sizes (LS). Repeated measurements of the BW and BCS were used as indicators of BR. The ewe PERF traits recorded were indirect measurements for maternal abilities and included: prolificacy, litter weight and lamb BW at lambing and weaning, ADG at 1, 2 and 3 months after lambing and litter survival from lambing to weaning. The effects of different BW and BCS trajectories (e.g., changes in BW and BCS across the production cycle), previously been characterized in the same animals, on PERF traits were investigated. Such trajectories reflected different profiles at the intraflock level in the dynamics of BR mobilization-accretion cycles. Genetic relationships between BR and PERF traits were assessed. All the fixed variables considered (i.e., YR, AGE, PAR, LS and SEX ratio of the litter) have significant effects on the PERF traits. Similarly, BW trajectories had an effect on the PERF traits across the three PARs studied, particularly during the first cycle (PAR 1). The BCS trajectories only affected prolificacy, lamb BW at birth and litter survival. Most of the PERF traits considered here showed moderate heritabilities (0.17 to 0.23) except for prolificacy, the lamb growth rate during the third month and litter survival which showed very low heritabilities. With exception of litter survival and prolificacy, ewe PERF traits were genetically, strongly and positively correlated to BW whatever the physiological stage. A few weak genetic correlations were found between BCS and PERF traits. As illustrated by BW and BCS changes over time, favorable genetic correlations were found, even if few and moderate, between BR accretion or mobilization and PERF traits, particularly for prolificacy and litter weight at birth. In conclusion, our results show significant relationships between BR dynamics and PERF traits in ewes, which could be considered in future sheep selection programs aiming to improve robustness.

International audience; The overall sustainability and innovative capacity of the sheep and goat sector in Europe have tobe improved to cope with current and future economic, environmental and societal challenges. Innovations ingenetic resource management and breeding for sheep and goat populations will be explored in the iSAGE Eu-ropean project (WP5) in order to help the industry to cope with such future challenges. In France, genetic eval-uation for small ruminants is performed in a large variability and poorly characterized environments. In this re-gard, we will consider multi-generation data from existing French breeding programs and experimental fieldstudies. Effects of herd for traits under genetic selection will be investigated in commercial farms in order tobetter characterize the production environment, particularly using meteorological data but also feeding, breed-ing system and economic criteria. Such characterization will enable to follow-up trends in animal performancesaccording to weather changes. This work could also contribute to characterize farm typologies to which a setof sustainability indicators will be tested. Then, contrasted environments will be identified and genotype by en-vironment interactions studies will be carried out aiming to improve genetic selection efficiency in a variety ofenvironments. In addition to existing data, we will explore new phenotypes considered as key functional traitsfor robustness and for which stakeholders are particularly interested. These new phenotypes will be also explored in combination with feed efficiency in experimental facilities under contrasted environments or under feedshortage challenges. Genetic and genomic studies will be performed for new phenotypes used to assess in-dividual robustness. The total merit indices will be revisited from the technical and economic point of view inorder to evaluate economic weights of each trait in the “breeding goal”, for diversified production systems.; En France, l’évaluation génétique des petits ruminants estime simultanément la valeur génétique des reproducteurs ainsi que les effets d’environnement dont le plus important est l’effet troupeau. Cette évaluation est réalisée dans des environnements variés et mal caractérisés faisant l’hypothèse d’absence d’interaction GxE. Pour tester cette hypothèse et disséquer les composantes des effets troupeaux, les environnements de production seront caractérisés à partir des données collectées en fermes (disponibles dans les systèmes nationaux d’information génétique ou collectées ponctuellement) décrivant les systèmes d’élevages et des données météorologiques. La discrimination des types d’environnements de production établis par la typologie des élevages permettra d’analyser les interactions GxE pour différentes races ovines et caprines en France. Par ailleurs, l’adaptation des petits ruminants à ces environnements variés et changeants implique entre autre leur efficacité d’utilisation des ressources et leur capacité biologique à mobiliser et reconstituer leurs réserves énergétiques sous forme de lipides. Des travaux expérimentaux seront conduits pour étudier les mécanismes biologiques et le déterminisme génétique de la dynamique des réserves corporelles en lien avec l’efficacité alimentaire. Cette approche permettra d’identifier de nouveaux phénotypes pour l’amélioration génétique de la robustesse des petits ruminants.

Le méthane entérique, représente une source importante de Gaz à effet de serre générés par l’élevage. En Afrique de l’Ouest les systèmes pastoraux traditionnels utilisent essentiellement les ressources herbacées naturelles, et périodiquement les fourrages ligneux, pour lesquels les niveaux d’émissions de méthane sont peu connus. Dans une approche prospective l’étude capitalise une importante base de données de fourrages ligneux et herbacés, dont la composition chimique a été prédite par SPIR et le potentiel méthanogène calculé selon les modèles de Sauvant et al. (2011) et Jayanegara et al.( 2012). Les résultats révèlent que les fourrages ligneux et les graminées tropicales ont tendances à émettre en moyenne plus de CH4, que les graminées tempérées (+ 10.3 et + 7.0 %). Toutefois lorsqu’elle est prise en compte leur teneur en tanins contribuerait à réduire la production potentielle de CH4 (16.8% et 2.3 %respectivement) nuançant les émissions potentielles de méthane., Enteric methane is one of the main sources of Green House Gaz produced by ruminant livestock. Traditional pastoral systems use local natural grassland resources for livestock feeding, including a wide diversity of ligneous forages browsed by ruminants in West Africa. However few studies assessed the methane emissions of such forages. This study analyzed a large collection of ligneous and herbaceous forages, looking for estimating their methanogenic potential by using their biochemical composition predicted by NIRS and two models available in the literature (Sauvant et al. 2011, Jayanegara et al. 2012). Results showed a higher CH4 production in ligneous forages and tropical grasses when compared to tempered grasses (+10.3 vs+7.0 % respectively). However, ligneous forages contain some tannins at higher concentrations, which according to the models would tend to decrease the methanogenic potential (-16.8% and -2.3%), thus nuancing the first methane emissions results.

The mixed crop-livestock systems (MCLS) are characterized by the diversity of productions and the crop- livestock integration (CLI) practices. From an agro-ecological perspective, four main emergent properties are expected from MCLS: resilience, productivity, efficiency and self-sufficiency. The objective was to assess, at farm level, the resilience of MLCS and explore if CLI could confer more resilience. We performed the study on 17 family farms in three territories of the humid tropics , Guadeloupe (8), Brazilian Amazonia (4) and Cuba (5), contrasted from a socio economic point of view, thus looking to cover a range of CLI configurations. The farms range from 2 to 100 ha, 1 to 5 workers and combine cattle or pigs, pasture or forage crops, and crops for food and cash. We used the ecological network analysis (ENA) method to study the flow network s of nitrogen (N) for a sample of seventeen farms. We characterized CLI in terms of intensity and organization of flow s, and examined the resilience of the N flow networks, from indicators of development capacity, ascendancy and overhead proposed by Ulanowicz and Norden (1990). The results show that both the intensity and organization of CLI flows are consistent in characterizing CLI in a range of situations i.e. from low CLI intensity based on few flows to high C LI intensity based on complex flows. The resilience indicator is independent of the intensity of the CLI practices at farm level. On the other hand, the resilience exhibits a strong correlation (r=0.9 1) with the organization of flows. The CLI seems effective in promoting resilience, viewed as the stability provided by the homogeneous distribution of flows among the farming system compartments. This study shows the interest of ENA quantifying CLI and resilience at farm level. The diversity of CLI flows provides a certain type of resilience, besides other interest like the nutrient recycling, leading to a better efficiency of N use.

Session 26: Mixed Farming systems does diversity bring any benefits and at what scale?; From an agroecological perspective, mixed crop-livestock systems (MCLS) can be characterized according to two main properties: i) diversity of production as a structural property and, ii) crop-livestock integration (CLI) as a functional property of the farming system. The objective of this work was to assess the resilience of a range of CLI configurations at system level. We conducted this analysis on three contrasting socioeconomic territories in the humid tropics: Guadeloupe, Brazilian Amazonia and Cuba, thus looking to cover a spectrum of CLI configurations. In order to analyze CLI in a holistic way, we used the ecological network analysis (ENA) method to study the flow networks of nutrients. We applied ENA to a sample of seventeen MCLS farms. We modelled them as a network of flows, using nitrogen as the “currency”. We then characterized CLI in terms of intensity and organization of flows, and examined the resilience of the flow networks. The results show that both the intensity and organization of CLI flows are consistent in characterizing CLI in a range of situations i.e. from low CLI intensity based on few flows to high CLI intensity based on complex flows. The CLI is especially effective in promoting resilience, viewed as the stability provided by the distribution of flow networks among the farming system compartments. This study proposes a suitable framework to analyze complex farming systems helping with a methodological support to the objectives of agroecological transition in agriculture.

This paper is the continuation of the one published in Pastos y Forrajes, no. 1, 2016, in which the general bases of a selection of currently internationally available methodologies for the dynamic evaluation of production systems, are offered. This part describes the methodologies Integral Energy Evaluation (EMERGY) and Systems’ Trajectory; and also a concrete example is provided of the application of the principles of these methods in the construction of an integral evaluation model of farming systems, called GAMEDE.

Le néologisme « agro-écologie » est apparu dans la littérature dans les années 30, d’abord pour désigner une discipline scientifique au carrefour de l’écologie et de l’agronomie, puis à partir des années 70 un ensemble de pratiques et un mouvement social en réaction à l’intensification de l’agriculture (Wezel et al., 2009). Francis et al. (2003) ont encore élargi cette définition en considérant l’ensemble des dimensions environnementales et socio-économiques à l’échelle des filières. Dans son acception scientifique, qui est l’angle choisi dans cette étude, l’agro-écologie se définit comme l’application des concepts et principes de l’écologie à la conception et à la gestion d’agroécosystèmes durables. La question du bouclage des cycles pour limiter les intrants et les pollutions par une meilleure réutilisation des sorties des différents ateliers est au coeur de ces problématiques. On vise également un recours accru à des régulations biologiques et écologiques que l’on cherche à piloter au mieux des attendus de l’élevage. Ceci implique de prendre en compte la diversité biologique à tous ses niveaux d'organisation, de comprendre et d’utiliser les capacités adaptatives des animaux et les interactions biotiques dans les agroécosystèmes, en considérant les systèmes de culture ou les systèmes d'élevage comme des écosystèmes particuliers (Dumont et al. 2013). Ainsi, l’agro-écologie s’inscrit-elle dans un mouvement de fond autour du « Comment produire autrement ? » dans des systèmes de production dont on cherche à concilier les performances techniques, environnementales, économiques et sociales. Lancé le 18 décembre 2012, le Projet Agro-Ecologique pour la France (PAEF) vise à conjuguer l’ensemble de ces performances tant au niveau de l'exploitation qu’au niveau collectif (territoires, filières, etc.). Il s’agit d’engager une évolution des systèmes de production, qui remette l’agronomie au coeur des pratiques, pour combiner ces différentes performances. La Loi n° 2014-1170 du 13 octobre 2014 dite Loi d'avenir pour l'agriculture, l'alimentation et la forêt en donne la définition suivante : « Les politiques publiques visent à promouvoir et à pérenniser les systèmes de production agro-écologiques, dont le mode de production biologique, qui combinent performance économique, sociale, notamment au travers d’un haut niveau de protection sociale, environnementale et sanitaire. Ces systèmes privilégient l'autonomie des exploitations agricoles et l'amélioration de leur compétitivité, en maintenant ou en augmentant la rentabilité économique, en améliorant la valeur ajoutée des productions et en réduisant la consommation d'énergie, d'eau, d'engrais, de produits phytopharmaceutiques et de médicaments vétérinaires, en particulier les antibiotiques. Ils sont fondés sur les interactions biologiques et l'utilisation des services écosystémiques et des potentiels offerts par les ressources naturelles, en particulier les ressources en eau, la biodiversité, la photosynthèse, les sols et l'air, en maintenant leur capacité de renouvellement du point de vue qualitatif et quantitatif. Ils contribuent à l'atténuation et à l'adaptation aux effets du changement climatique.