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Generation and distribution of productivity gains in beef cattle farming: Who are the winners and losers between 1980 and 2015?
No full textSurplus accounting is a method for evaluating trends in how a firm’s productivity factors (intermediate inputs, capital, land, labour)
are performing and how the productivity gains are redistributed between agents in the economy. Here the surplus accounting
method was applied on a database of 164 Charolais-area suckler cattle farms running from 1980 to 2015. Over this 36-year period –
with differences per sub-period – the cumulative productivity surplus (PS) increased at a low rate of +0.17%/year (i.e. cumulative
volume of outputs produced increased slightly more than cumulative volume of inputs used). This timid increase in PS is linked to
the constant expansion in labour productivity whereas other factor productivities have shrunk. The observable period-wide
macrotrends are that commercial farm businesses struggle to protect their revenues, we also observe a slight fall in input prices,
land rent and financing costs, and a huge climb in direct support-policy payments. The bulk of the cumulative economic surplus has
been captured downstream – 64% downstream of the cattle value chain as a drop in prices, and 22% downstream of other value
chains (chiefly cereals). It emerges that the productivity gains in beef cattle farming mostly benefit the downstream value chain
(packers–processors, distributors and consumers), whereas it is mainly government money backing this drop in prices of agricultural
output. Here we see the principal of the 1992 ‘MacSharry’ reform at work, with a transfer from the taxpayer through direct supportpolicy
payments through to the consumer via lower prices. The simple fact that farmers’ incomes are stagnating is a clear indication
that they are net losers in this distribution of productivity gains, despite the improvement in labour factor productivity
Price interactions between wild and farmed products: Turkish sea bass and sea bream markets
No full textWe investigate empirically market interactions in the Turkish wild and farmed sea bass and sea bream markets. For gilthead sea bream and European sea bass, we conduct a Granger causality test between the prices of the wild and farmed products, based on the estimation of a vector autoregressive model. Our data set consists of annual fish prices from 1996 to 2016. Our empirical results show that the wild and farmed sea bass are neither substitutes nor complements : the markets for each product are independent. However, in the case of sea bream, the price variations for farmed sea bream have a causal impact on the price of wild sea bream. Moreover, the price of wild sea bream Granger-causes the price variation of farmed sea bream. Thus, the wild and farmed sea bream markets are integrated.Nous conduisons une analyse empirique pour étudier les interactions de prix sur les marchés de bar et de dorade sauvage et cultivé en Turquie. Pour le bar et la dorade, nous effectuons un test de causalité de Granger entre les prix des produits sauvages et des produits d'élevage, basé sur l'estimation d'un modèle vectoriel autorégressif. Notre base de données comprend les prix annuels des produits de 1996 à 2016. Nos résultats empiriques montrent que le bar sauvage et le bar d'élevage ne sont ni des substituts ni des compléments: les marchés pour chaque produit sont indépendants. Cependant, dans le cas de la dorade, les variations de prix de la dorade d'élevage ont un impact causal sur le prix de la dorade sauvage. En outre, le prix de la dorade sauvage a un impact causal sur la variation du prix de la dorade d’élevage. Ainsi, les marchés de dorade sauvage et d'élevage sont intégrés
Protective Effect of Resveratrol against Ischemia-Reperfusion Injury via Enhanced High Energy Compounds and eNOS-SIRT1 Expression in Type 2 Diabetic Female Rat Heart
No full textType 2 diabetic women have a high risk of mortality via myocardial infarction even with anti-diabetic treatments. Resveratrol (RSV) is a natural polyphenol, well-known for its antioxidant property, which has also shown interesting positive effects on mitochondrial function. Therefore, we aim to investigate the potential protective effect of 1 mg/kg/day of RSV on high energy compounds, during myocardial ischemia-reperfusion in type 2 diabetic female Goto-Kakizaki (GK) rats. For this purpose, we used P-31 magnetic resonance spectroscopy in isolated perfused heart experiments, with a simultaneous measurement of myocardial function and coronary flow. RSV enhanced adenosine triphosphate (ATP) and phosphocreatine (PCr) contents in type 2 diabetic hearts during reperfusion, in combination with better functional recovery. Complementary biochemical analyses showed that RSV increased creatine, total adenine nucleotide heart contents and citrate synthase activity, which could be involved in better mitochondrial functioning. Moreover, improved coronary flow during reperfusion by RSV was associated with increased eNOS, SIRT1, and P-Akt protein expression in GK rat hearts. In conclusion, RSV induced cardioprotection against ischemia-reperfusion injury in type 2 diabetic female rats via increased high energy compound contents and expression of protein involved in NO pathway. Thus, RSV presents high potential to protect the heart of type 2 diabetic women from myocardial infarction
Honey bees long-lasting locomotor deficits after exposure to the diamide chlorantraniliprole are accompanied by brain and muscular calcium channels alterations
No full textDiamides belong to one of the newest insecticides class. We characterized cellular effects of the first commercialized diamide, chlorantraniliprole (ChlorAnt). ChlorAnt not only induces a dose-dependent calcium release from internal stores of honey bee muscle cells, but also a dose-dependent blockade of the voltage-gated calcium current involved in muscles and brain excitability. We measured a long lasting impairment in locomotion after exposure to a sublethal dose and despite an apparent remission, bees suffer a critical relapse seven days later. A dose that was sublethal when applied onto the thorax turned out to induce severe mortality when applied on other body parts. Our results may help in filling the gap in the toxicological evaluation of insecticides that has recently been pointed out by international instances due to the lack of suitable tests to measure sublethal toxicity. Intoxication symptoms in bees with ChlorAnt are consistent with a mode of action on intracellular calcium release channels (ryanodine receptors, RyR) and plasma membrane voltage-gated calcium channels (CaV). A better coupling of in vitro and behavioral tests may help in more efficiently anticipating the intoxication symptoms
Genetic and environmental dissection of biomass accumulation in multi-genotype maize canopies
No full textMulti-genotype canopies are frequent in phenotyping experiments and are of increasing interest in agriculture. Radiation interception efficiency (RIE) and radiation use efficiency (RUE) have low heritabilities in such canopies. We propose a revised Monteith equation that identifies environmental and genetic components of RIE and RUE. An environmental term, a component of RIE, characterizes the effect of the presence or absence of neighbours on light interception. The ability of a given plant to compete with its neighbours is then identified, which accounts for the genetic variability of RIE of plants having similar leaf areas. This method was used in three experiments in a phenotyping platform with 765 plants of 255 maize hybrids. As expected, the heritability of the environmental term was near zero, whereas that of the competitiveness term increased with phenological stage, resulting in the identification of quantitative trait loci. In the same way, RUE was dissected as an effect of intercepted light and a genetic term. This approach was used for predicting the behaviour of individual genotypes in virtual multi-genotype canopies. A large effect of competitiveness was observed in multi-genotype but not in single-genotype canopies, resulting in a bias for genotype comparisons in breeding fields
Accuracy of genomic evaluation with weighted single-step genomic best linear unbiased prediction for milk production traits, udder type traits, and somatic cell scores in French dairy goats
No full textGenomic evaluation of French dairy goats is routinely conducted using the single-step genomic BLUP (ssGBLUP) method. This method has the advantage of simultaneously using all phenotypes, pedigrees, and genotypes. However, ssGBLUP assumes that all SNP explain the same amount of genetic variance, which is unlikely in the case of traits whose major genes or QTL are segregating. In this study, we investigated the effect of weighted ssGBLUP and its alternatives, which give more weight to SNP associated with the trait, on the accuracy of genomic evaluation of milk production, udder type traits, and somatic cell scores. The data set included 2,955 genotyped animals and 2,543,680 pedigree animals. The number of phenotypes varied with the trait. The accuracy of genomic evaluation was assessed on 205 genotyped Alpine and 146 genotyped Saanen goats born between 2009 and 2012. For traits with unknown QTL, weighted ssGBLUP was less accurate than, or as accurate as, ssGBLUP. For traits with identified QTL (i.e., QTL only present in the Saanen breed), weighted ssGBLUP outperformed ssGBLUP by between 2 arid 14%
Projet Sclerotinia sclerotiorum : meilleure connaissance du champignon pathogène, évaluation du risque et évaluation de méthodes de protection
No full textLe champignon phytopathogène Sclerotinia représente ces dernières années un problème croissant pour les producteurs du fait d’une recrudescence des dégâts et de moyens de protection ne donnant pas satisfaction. Les objectifs du projet Sclérolég visent à proposer aux producteurs des stratégies de protection combinant différentes techniques pour une meilleure maîtrise de Sclerotinia. Le premier axe a cherché à combler le manque de connaissances sur la variabilité du pathogène et à mieux comprendre le développement des épidémies et les processus épidémiologiques clefs mis en jeu. Par ailleurs le deuxième axe a été d’évaluer des outils de prévisions des risques ainsi que de développer de nouveaux outils. Enfin la combinaison de différentes techniques de protection Sclérolég a été expérimentée et évaluée pour proposer aux producteurs des systèmes de production innovants et durables. Les souches de S. sclerotiorum caractérisées dans le cadre du projet se sont montrées très diverses au niveau génétique et en capacité de faire des symptômes sur l’ensemble des cultures testées, ce qui confirme l’absence de spécialisation d’hôte. Différents tests ont été mis au point en particulier pour caractériser l’agressivité du pathogène. Concernant le processus infectieux, le projet a montré toute l’importance que revêtent les ascospores en particulier pour les cultures de melon. La présence de Sclerotinia subartica a été détectée pour la première fois en France mais reste très minoritaire par rapport à S. sclerotiorum. Concernant la quantification de l’inoculum du sol, deux techniques originales de quantification ont été mises au point: l’élutriation et l’utilisation de carottes pièges. En termes de gestion du potentiel infectieux des parcelles, certains points sur le comportement de C. minitans (CONTANS®) sont approfondis. Enfin, les agents de biocontrôle expérimentés dans le cadre de Sclérolég n’ont pas permis d’obtenir un contrôle satisfaisant du bioagresseur.The fungus Sclerotinia has been an increasing problem for producers in recent years due to increasing damages and unsatisfactory means of protection. The objectives of the Sclérolég project were to offer to growers some protection strategies combining different techniques for a better control of sclerotinia. The first axis sought to fill the knowledge gap on the variability of the pathogens and also to better understand the development of epidemics and the key epidemiological processes involved. In addition, one of the objectives was to evaluate risk prediction tools and develop new tools. Finally, the combination of different protection techniques was tested and evaluated to offer producers innovative and sustainable production systems in Scleroleg. The strains of S. sclerotiorum characterized in the project were very diverse at the genetic level and in their ability to cause symptoms in all the crops tested, which confirms the absence of specialization. Various tests were developed in particular to characterize the aggressiveness of the pathogen. Concerning the infectious process, the project showed how important ascospores are, especially for melon cultures. Sclerotinia subartica was reported for the first time in France. Concerning the quantification of soil inoculum, two original quantification techniques were developed: elutriation and the use of trap cores. In terms of managing the infectious potential of the plots, some points on the behavior of C. minitans (CONTANS®) were examined in details. Finally, the biocontrol agents experimented in Scleroleg did not provide satisfactory control of the pest infestation
Contrasting effects of wild arachis dehydrin under abiotic and biotic stresses
No full textPlant dehydrins (DNHs) belong to the LEA (Late Embryogenesis Abundant) protein family and are involved in responses to multiple abiotic stresses. DHNs are classified into five subclasses according to the organization of three conserved motifs (K-; Y-; and S-segments). In the present study, the DHN protein family was characterized by molecular phylogeny, exon/intron organization, protein structure, and tissue-specificity expression in eight Fabaceae species. We identified 20 DHN genes, encompassing three (YnSKn, SKn, and K-n) subclasses sharing similar gene organization and protein structure. Two additional low conserved DHN Phi-segments specific to the legume SKn-type of proteins were also found. The in silico expression patterns of DHN genes in four legume species (Arachis duranensis, A. ipaensis, Glycine max, and Medicago truncatula) revealed that their tissue-specific regulation is associated with the presence or absence of the Y-segment. Indeed, DHN genes containing a Y-segment are mainly expressed in seeds, whereas those without the Y-segment are ubiquitously expressed. Further qRT-PCR analysis revealed that, amongst stress responsive dehydrins, a SKn-type DHN gene from A. duranensis (AdDHN1) showed opposite response to biotic and abiotic stress with a positive regulation under water deficit and negative regulation upon nematode infection. Furthermore, transgenic Arabidopsis lines overexpressing (OE) AdDHN1 displayed improved tolerance to multiple abiotic stresses (freezing and drought) but increased susceptibility to the biotrophic root-knot nematode (RKN) Meloidogyne incognita. This contradictory role of AdDHN1 in responses to abiotic and biotic stresses was further investigated by qRT-PCR analysis of transgenic plants using a set of stress-responsive genes involved in the abscisic acid (ABA) and jasmonic acid (JA) signaling pathways and suggested an involvement of DHN overexpression in these stress-signaling pathways
Annotation data about multi criteria assessment methods used in the agri-food research: The french national institute for agricultural research (INRA) experience
No full textThis data article contains annotation data characterizing MultiCriteria Assessment (MCA) Methods proposed in the agri-food sector by researchers from INRA, Europe's largest agricultural research institute (INRA, http://institut.inra.fr/en). MCA can be used to assess and compare agricultural and food systems, and
support multi-actor decision making and design of innovative systems for crop production, animal production and processing of agricultural products. These data are stored in a public repository managed by INRA (https://data.inra.fr/; https://doi.org/10.15454/WB51LL)