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Livestock farming eco-efficiency analysis: a systematic literature review of frontier approaches for sustainability
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Adaptations comportementales des vaches laitières aux contraintes d’abreuvement selon leur position sociale
No full textRecommendations exist to ensure that dairy herds do not suffer from prolonged thirst. However, the current evaluation criteria for on-farm watering systems, on which these recommendations are based, induces an obligation of means but not of results. This thesis has shown that rearing conditions observed on farms can affect animal drinking behavior, with heterogeneous responses between animals. During this work, a method was sought to automatically characterize the social hierarchy established at drinking troughs. Experiments were then conducted to simulate a variety of on-farm housing conditions, with constraints on watering. The results suggest that current recommendations regarding the number of animals per trough still guarantee the absence of prolonged thirst.On the other hand, the most subordinate animals in the herd seemed to find it more difficult to adapt to constraints such as an increase in the density of animals at water troughs or temporal restrictions on access to water. These temporal constraints also affected the resting time of the cows. Although all the cows managed to drink sufficiently, these results suggest that these constraints could affect their well-being. Finally, the experiments showed that certain parameters of drinking behavior, such as drinking rates or the distributions of watering into drinking bouts, could be used in future to develop new indicators to better characterize the absence of prolonged thirst in all cows in dairy herds.Il existe des recommandations pour garantir l'absence de soif dans les troupeaux. Cependant, les critères d'évaluation des équipements d'abreuvement sur lesquels reposent ces recommandations répondent à des obligations de moyens mais pas de résultats. Cette thèse a montré comment des conditions d'élevage variées, observables dans les fermes, peuvent affecter l'abreuvement des animaux et refléter leur hétérogénéité de réponse face à certaines situations. La recherche d'une méthode d'identification automatique de la hiérarchie social qui s'établit aux abreuvoirs a été menée. Puis, des expérimentations simulant des conditions d'élevage variées visibles en ferme, avec des contraintes sur l'abreuvement, ont été mises en œuvre. Les résultats suggèrent que les recommandations actuelles en matière de nombre d'animaux par abreuvoir garantissent toujours l'absence de soif prolongée. En revanche, les animaux les plus subordonnés des troupeaux semblent avoir plus de mal à s'adapter à des contraintes telles que des augmentations de la densité d'animaux aux abreuvoirs ou des restrictions temporelles d'accès à l'eau. Ces contraintes temporelles ont également affecté le temps de repos des vaches. Ainsi, bien que toutes les vaches aient réussi à s'abreuver de manière suffisante, ces résultats suggèrent que ces contraintes pourraient affecter leur bien-être. Les expérimentations menées ont enfin mis en évidence que certains comportements liés à l'abreuvement, tels que la vitesse d'abreuvement ou les épisodes de buvées, pourraient, à l’avenir, servir de base pour créer de nouveaux indicateurs, afin de mieux caractériser l'absence de soif prolongée pour toutes les vaches des troupeaux laitiers
Beyond Porter hypothesis : Empirical evidence of heterogeneous and contextual economic returns of eco-innovations on a sample of European SMEs.
No full textInternational audienceThe various versions of the Porter hypothesis suggest that well-designed environmental public policies may have positive effects on eco-innovation adoption and on the profitability of enterprises on the long run. However, these effects may be heterogeneous depending on the eco-innovation at stake and influenced by the other enterprises in competition. Using a repeated cross-country European survey on SME, we estimate mixed Ordered Probit with correlated random effects and sample selection. We are able to disentangle direct and indirect determinants of costs while accounting for the internal, contextual and public policies levers of ecoinnovation adoption. While testing the three versions of Porter's hypothesis, we extend previous work by taking into account the heterogeneous impact of different eco-innovations on profitability, on the one hand, and the impact of eco-innovation adoption by one firm on another, on the other hand. Our results have valuable policy implications for policymakers and SMEs
Nutritional quality of proteins from two beef co-products as determined in the growing pig
No full textInternational audienceThe increasing demand for food and especially proteins leads to the search for alternative protein sources. Meat co-products, which are available but little used in human food, provide a potential solution to this challenge. The present study aimed to evaluate the nutritional quality of two beef protein ingredients (greasy greaves recovered proteins (GGRP) and water recovered proteins (WRP)), both co-products of the fat rendering process. Their true ileal digestibility (TID), digestible indispensable amino acid score (DIAAS) and kinetics of plasma amino acids (AA) were measured in ten growing pigs, each fed the two co-products and a protein-free diet. Titanium dioxide was used as an indigestible marker. Digesta samples were collected for 9 h after meal ingestion, and blood samples were collected at ten time points during the same period. Total nitrogen (N) and AA contents were determined. Data were statistically analysed using linear mixed models. The TID of total N was not different between WRP and GGRP (81-84 %, P > 0•05). The first-limiting AA was Trp for both ingredients, with a DIAAS much higher for GGRP than for WRP (74 and 10 % for adults, respectively; P < 0•001). Postprandial plasma AA concentration peaked earlier for WRP (3 h) than for GGRP (5 h). Plasma concentrations of total and essential AA were higher (P < 0•001) with GGRP diet than WRP diet. Overall, GGRP has a nutritional quality suitable to meet the needs of adults for AA, while WRP needs to be supplemented with other protein sources to fulfil the dietary requirements
Protein ingredient quality of infant formulas impacts gut physiology and microbiota in mini-piglets used as a human infant model
No full textInternational audienceInfant formulas (IFs), the only adequate substitute to human milk, are complex matrices that require numerous ingredients and processing steps. Previously, we showed that the quality of the dairy protein ingredients within IFs modulated protein microstructure and in vitro and in vivo digestive kinetics. Therefore, the aim was to assess the impact of protein ingredient quality (composition and structure) on gut physiology and microbiota. Three isonitrogenous IFs were formulated with whey proteins from different origins (cheese whey: IF-A, vs. ideal whey: IFs-B/C) and casein with different organizations (micellar: IFs-A/B, vs. non-micellar: IF-C). Twenty-four Yucatan mini-piglets (2- to 21-day-old), used as an infant model, received one of the three IFs. Digestive contents, faeces, and tissues were analysed using metagenomic, histological, ex vivo permeability and gene expression approaches and a metabolomic analysis was done on serum. Univariate and multivariate statistical analyses were performed. The increase of colonic paracellular permeability associated with a slight immune boost, and the changes in colonic amino acid transporter expression in IF-C compared with IF-A fed piglets, suggested a combined effect of whey origin and casein supramolecular organization on intestinal physiology in favour of IF-C, whose parameters were closer to those recently reported for human milk-fed piglets (Charton et al., 2022). Gut microbiota composition was moderately changed between diets, whereas faecal short-chain fatty acid composition differed according to whey protein origin. Differences in microbiota fermentative activity may result from differences in digestive kinetics previously observed in vitro between cheese whey-based IF (A) and ideal whey-based IFs (B and C), which could modulate the colonic substrate available for the microbiota. Serum metabolomic data are currently being analysed and may provide a better understanding of the mechanisms involved. The use of ideal whey and the modulation of casein organization appear to be possible avenues for improving IFs
Macronutrient digestion and nutritional quality: how to measure it and what matters?
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Transgenerational response to an endocrine disruptor ingestion : phenotypic, genetic and epigenetic analyses in quail.
No full textInternational audienceTypical prediction of an offspring's phenotype usually focuses on the inheritance of parental alleles. However, variations across generations can also result from the transmission of non-genetic factors. Epigenetic marks such as DNA methylation offer a dynamic molecular signature of an individual's history, as they can carry a memory of the individual's environmental past, and probably of its ancestors. In this study, we aim to analyze the impact of an initial supplementation with an endocrine disruptor, the genistein, on the phenotypes of subsequent generations. To better disentangle the complex interplay between genetic and epigenetic effects, a specific quail (Coturnix japonica) breeding plan was designed, where mirror crosses tend to ensure a balanced genetic structure between epilines. By recording multiple phenotypes (growth, breeding, production, behaviour) across three generations, our goal is to investigate the transgenerational inheritance of an environmental effect through changes in DNA methylation profiles. Here we present the preliminary results obtained on phenotypic analysis
Silvopastoral systems for the mitigation of nitrogen losses in the short and the long-term: a case study at dairy farm scale and research perspectives
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Organic pig farming: from feeding strategy to meat organoleptic quality
No full textInternational audiencePig diet is one of the major factors from farm to fork determining pork quality attributes, including organoleptic traits (appearance, texture, flavour and odour). An experiment was conducted with 77 organic uncastrated male pigs (Piétrain x Large White) in two batches in time, each divided in two groups. One group received a control diet (C) corresponding to the organic specifications. The other group received a test diet (Bio+), mainly based on French raw materials, containing more fibre (Faba bean) and omega-3 fatty acids (linseed, camelina) and had access to forage. Each group was reared in one pen in the same building on deep straw bedding with free outdoor access and fed ad libitum until slaughter. Meat was analysed by a trained sensory panel and by SPME-GC-MS to identify the main odor-active volatile compounds. Meat was lighter (P<0.05) and had a more intense red colour (P<0.1) in Bio+ than in C pigs. Meat from Bio+ pigs had a lower aromatic persistency (P<0.05), whereas odour intensity, tenderness and juiciness did not significantly differ between the groups. None of the samples were qualified as boar tainted by the panellists. Identified volatile compounds belonged to aldehydes, hydrocarbons, alcohols and ketones. Of the 29 compounds identified, 10 had a prevalence of over 50%, with the same proportion in C and Bio+ pigs. Only two compounds, benzaldehyde (almond odour) and heptanal (fatty odour) were found in all samples. Finally, the Bio+ diet influenced some sensory properties but did not modify the odour, flavour or aromatic profile of pork. A joint analysis of the volatile profile and sensory data is planned as part of the global-quality approach
Molènes hybrides de France, 14 - Verbascum ×fluminense A. Kern. ex Rouy nothosubsp. fluminense (V. chaixii Vill. subsp. chaixii × V. pulverulentum Vill.)
No full textInternational audienceThe hybrid Verbascum chaixii subsp. chaixii × V. pulverulentum has recently been observed in the Hérault part of the Causse du Larzac. The taxonomy of this hybrid is updated and a lectotype is designated. The morphology of this hybrid is compared with that of its parents using an illustrated table with comments. The available data are compiled and illustrated by maps of known and potential distribution.L’hybride Verbascum chaixii subsp. chaixii × V. pulverulentum a récemment été observé sur la partie héraultaise du Causse du Larzac. La taxonomie de cet hybride est actualisée et un lectotype est désigné. La morphologie de cet hybride est comparée avec celle de ses parents grâce à un tableau illustré et commenté. Les données disponibles sont compilées et illustrées par des cartes de répartition connue et potentielle