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Preferences for index-based pasture insurance: a choice experiment in Limpopo Province, South Africa
No full textInternational audienceSouth African subsistence livestock farmers rely heavily on traditional mitigation and coping mechanisms to deal with the effects of drought. However, these methods have proven ineffective in managing the full impact of drought. Consequently, policymakers are increasingly interested in promoting Index-based Pasture Insurance (IBPI). This paper aims to assess subsistence livestock farmers' preferences for IBPI. A simple random sampling method was used to select 110 subsistence livestock farmers for data collection. A discrete choice experiment-Conditional Logit and Latent Class models and incentivized lottery games were used to elicit preferences for insurance contracts and loss aversion. The findings indicate that subsistence livestock farmers have a favourable attitude toward IBPI contracts that protect against drought-related pasture degradation. The Conditional Logit model shows that farmers prefer transparent contracts that reimburse with feed and vouchers rather than cash. However, they derive negative marginal utility from basis risk and premium. However, the Latent Class model reveals heterogeneous preferences for IBPI among farmers. Farmers are also loss-averse, but loss aversion did not influence their preference for IBPI. Therefore, the primary recommendation for insurance providers is to consider customizing IBPI attributes to increase adoption among subsistence farmers
Genetic Diversity and Virulence of Phytopathogenic Burkholderia glumae Strains Isolated from Rice Cultivars in Valleys of the High Jungle of Perú
No full textInternational audienceBurkholderia glumae causes bacterial leaf blight in rice, and its global spread has been exacerbated by climate change. To understand the genetic diversity and virulence of B. glumae strains isolated from rice cultivars in Perú, 47 isolates were obtained from infected rice fields, all belonging to B. glumae, and confirmed by recA and toxB sequences. The BOX-PCR typing group has 38 genomic profiles, and these turn into seven variable number tandem repeats (VNTR) haplotypes. There was no correlation between clustering and geographical origin. Nineteen strains were selected for phenotypic characterization and virulence, using both the maceration level of the onion bulb proxy and inoculation of seeds of two rice cultivars. Several strains produced pigments other than toxoflavin, which correlated with onion bulb maceration. In terms of virulence at the seed level, all strains produced inhibition at the root and coleoptile level, but the severity of symptoms varied significantly between strains, revealing significant differences in pathogenicity. There is no correlation between maceration and virulence scores, probably reflecting different virulence mechanisms depending on the host infection stage. This is the first study to evaluate the VNTR diversity and virulence of Peruvian strains of B. glumae in two commercial cultivars
Forest exploitation in the plains of early medieval northern Catalonia: Anthracological review
No full textInternational audienceIn the northwestern Mediterranean (Mediterranean France, Catalonia), the Early Middle Ages were a period of major change with a restructuration of rural settlements, that impacted both landscape management and how animal and plant resources were exploited. Recent bioarchaeological research has enabled us to understand the agropastoral changes associated with these new dynamics at a local scale, but their impact on the evolution of forest cover remains unevenly documented. The anthracological study of 8 rural archaeological sites located in the plains of early medieval northern Catalonia has made it possible to qualify the composition and state of the forests exploited by the local populations. The vegetation on the lower plains appears to be more open than in the hinterland, where human pressure on the environment appears to have been more moderate. Among the sites, Pujals seems to have drawn some of its fuel from the Pyrenees Mountain, raising the question of wood trading networks between the mountain and the plains at the time
Animal welfare as a public good
No full textNational audienceWe study a simple model of consumption of animals in which consumers exhibit altruism towards animals. Consumers can choose both the quantity and the quality of animal lives. This model gives rise to a public good problem: at the market equilibrium, quality is too low, and quantity is too high when animal lives are not worth living. We discuss some implications of our results and the significance of our modeling choices for the future landscape of economic research on animal welfare
Modeling the impact of rainfall and temperature on sterile insect control strategies in a Tropical environment
No full textInternational audienceThe sterile insect technique (SIT) is a biological control technique that can be used either to eliminate or decay a wild mosquito population under a given threshold to reduce the nuisance or the epidemiological risk. In this work, we propose a model using a differential system that takes into account the variations of rainfall and temperature over time and study their impacts on sterile males' releases strategies. Our model is as simple as possible to avoid complexity while being able to capture the temporal variations of an Aedes albopictus mosquito population in a domain treated by SIT, located in Réunion island. The main objective is to determine what period of the year is the most suitable to start a SIT control to minimize the duration of massive releases and the number of sterile males to release, either to reduce the mosquito nuisance, or to reduce the epidemiological risk. Since sterilization is not 100% efficient, we also study the impact of different levels of residual fertility within the released sterile males population. Our study shows that rainfall plays a major role in the dynamics of the mosquito and the SIT control, that the best period to start a massive SIT treatment lasts from July to December, that residual fertility has to be as small as possible, at least for nuisance reduction. Indeed, when the main objective is to reduce the epidemiological risk, we show that residual fertility is not necessarily an issue. Increasing the size of the releases is not always interesting. We also highlight the importance of combining SIT with mechanical control, i.e. the removal of breeding sites, in particular when the initial mosquito population is large. Last but not least our study shows the usefulness of the modeling approach to derive various simulations to anticipate issues and demand in terms of sterile insects' production
Urban school neighborhoods dominated by unhealthy food retailers and advertisements in Greater Tunis : a geospatial study in the midst of the nutrition transition.
No full textInternational audienceObjective: Food environments are a major determinant of children’s nutritional status. Scarce evidence on food environments exists in low and middle-income countries (LMICs). This study aims to fill this gap by documenting the obesogenicity of food environments around schools in Greater Tunis, Tunisia – an LMIC of the Middle East and North Africa region with an ongoing nutrition transition and increasing rates of childhood obesity. Design: In this cross-sectional study, we assessed built food environments around 50 primary schools. Ground-truthing was performed to collect geographic coordinates and pictures of food retailers and food advertisement-sets within an 800-meter road-network buffer of each school. Retailers and advertisement-sets were categorized as healthy or unhealthy according to a NOVA-based classification. Associations between school characteristics and retailers or advertisement-sets were explored using multinomial regression models. Setting: Greater Tunis, Tunisia. Participants: Random sample of 50 (35 private and 15 public) primary schools. Results: Overall, 3,621 food retailers and 2,098 advertisement-sets were mapped. About two thirds of retailers and advertisement-sets were labeled as unhealthy. Most retailers were traditional corner stores (22%) and only 6% were fruit and vegetable markets. The prevailing food group promoted was carbonated and sugar-sweetened beverages (22%). The proportion of unhealthy retailers was significantly higher in the richest vs. poorest areas. Conclusions: School neighborhood food environments included predominantly unhealthy retailers and advertisements. Mapping of LMIC food environments is crucial to document the impact of the nutrition transition on children’s nutritional status. This will inform policies and interventions to curb the emergent childhood obesity epidemic
OrthoMaM v12: a database of curated single-copy ortholog alignments and trees to study mammalian evolutionary genomics
No full textThe data underlying this article are available at https://orthomam.mbb.cnrs.fr.International audienceAbstract:To date, the databases built to gather information on gene orthology do not provide end-users with descriptors of the molecular evolution information and phylogenetic pattern of these orthologues. In this context, we developed OrthoMaM, a database of ORTHOlogous MAmmalian Markers describing the evolutionary dynamics of coding sequences in mammalian genomes. OrthoMaM version 12 includes 15,868 alignments of orthologous coding sequences (CDS) from the 190 complete mammalian genomes currently available. All annotations and 1-to-1 orthology assignments are based on NCBI. Orthologous CDS can be mined for potential informative markers at the different taxonomic levels of the mammalian tree. To this end, several evolutionary descriptors of DNA sequences are provided for querying purposes (e.g. base composition and relative substitution rate). The graphical web interface allows the user to easily browse and sort the results of combined queries. The corresponding multiple sequence alignments and ML trees, inferred using state-of-the art approaches, are available for download both at the nucleotide and amino acid levels. OrthoMaM v12 can be used by researchers interested either in reconstructing the phylogenetic relationships of mammalian taxa or in understanding the evolutionary dynamics of coding sequences in their genomes. OrthoMaM is available for browsing, querying and complete or filtered download at https://orthomam.mbb.cnrs.fr.Graphical Abstract:https://academic.oup.com/view-large/figure/421140867/gkad834figgra1.jp
Short-term responses of meat ewes facing an acute nutritional challenge in early-mid lactation
No full textInternational audienceSimulating a consequence of a climate change event on feed availability, responses of Mediterranean meat ewes facing an acute undernutritional challenge (CHA; i.e., fed only low nutritional value cereal straw) were evaluated at a sensitive physiological stage (i.e., early suckling). Forty Romane ewes were chosen at early-mid pregnancy (around 2 mo) according to parity (20 primiparous, PRIM; 20 multiparous, MULT); feed efficiency genetic line of their sires (residual feed intake [RFI]; efficient, RFI−, n = 10 per parity; inefficient, RFI+, n = 10 per parity); litter size (i.e., bearing twins, diagnosed by ultrasonography); body weight (BW, kg) and body condition score (BCS) (initial BW and BCS [mean ± SD]: 51.6 ± 7.41 kg; 2.5 ± 0.20, respectively; representing flock’ averages per parity). Effects on dry matter intake (DMI), ewes’ BW and BCS, subcutaneous dorsal fat thickness (DFT), energy metabolism (plasma non-esterified fatty acids [NEFA], β-hydroxybutyrate (β-OHB), glucose, urea, triiodothyronine [T3]), and lambs’ growth (BW and average daily gain [ADG]; g/d) were examined before, during and after CHA. Individuals’ profiles of the response-recovery to CHA were described using a piecewise mixed-effects model. The fixed effect of parity and genetic line and the random effect of individual (ewe) were considered. A linear mixed-effects model was fitted to explore the effects on lambs’ growth. The 2-d straw-only CHA had significant effects on most of the recorded parameters. Meaningful drops and recoveries were observed on ewes’ DMI, BW, and DFT with effect on postchallenge levels. BW, BCS, DFT, or DMI were also affected by parity (MULT > PRIM) but not by genetic line. Plasma NEFA, β-OHB, glucose, urea, and T3 responded well to CHA with drops in T3, urea, and glucose levels, whereas NEFA and β-OHB significantly increased after CHA. MULT ewes presented sharper β-OHB recovery from CHA than PRIM (P ≤ 0.05). With this study, we provide tangible and necessary data for an emerging field of research. Our results give new insights into how such a short and abrupt CHA affects some key zootechnical and physiological parameters, and to what extent the impacts of CHA and the ewes’ response-recovery are influenced. It also revealed potential between-individual differences in the adaptive capacities of ewes, which require further exploration
Why incorporate plant architecture into trait-based ecology?
No full textInternational audienceTrait-based ecology has improved our understanding of the functioning of organisms, communities, ecosystems, and beyond. However, its predictive ability remains limited as long as phenotypic integration and temporal dynamics are not considered. We highlight how the morphogenetic processes that shape the 3D development of a plant during its lifetime affect its performance. We show that the diversity of architectural traits allows us to go beyond organ-level traits in capturing the temporal and spatial dimensions of ecological niches and informing community assembly processes. Overall, we argue that consideration of multilevel topological, geometrical, and ontogenetic features provides a dynamic view of the whole-plant phenotype and a relevant framework for investigating phenotypic integration, plant adaptation and performance, and community structure and dynamics