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Economics of vaccination against diarrhoea and respiratory diseases in French cow calves' systems: A modelling approach
Get PDFTo assess the economic benefits of vaccination against diarrhoea and respiratory diseases in cow-calf systems, a stochastic mechanistic mathematical programming bio-economic model was developed for a beef Charolais breed farm. The model reproduced herd dynamics on a weekly basis over a 10-year period, including animal growth, reproduction and diseases risks and control (treatments and vaccination). Three baseline risk levels of diarrhoea and respiratory disease were considered to simulate low, average, and high infection risks on the farm. The results demonstrated the model's ability to reproduce average farm dynamics, with diarrhoea prevalence ranging from 8% to 33% and respiratory diseases from 13% to 79%. On average, prevalences were decreased by 24% and 50%, respectively, due to vaccination, which also reduced the 2-day to 1-month mortality rates by 2–3% and 15–17%, respectively. The net value of vaccination was positive except in cases of low infection risk of diarrhoea and respiratory diseases: the return on investment (ROI) of vaccination was 0.4–0.5 (€1 invested yields €0.4–0.5) in the baseline scenario (middle infection risks), negative under low infection risks, and reached 1 (€1 invested yields €1) for high infection risks. The results also showed that farmers may earn €58–75 in additional revenue per extra hour of labour dedicated to vaccination in the medium-risk scenario. Despite the limited availability of data for cow-calf systems, this study demonstrated the economic benefit of vaccination in most combinations of scenarios and risks. The profitability of vaccination was challenged when low disease risks were considered, but in such cases, vaccination may serve as insurance against financial losses in case of health status deterioration
Body measurements and body condition scoring in Bactrian camels
Get PDFBody measurements are used regularly to describe phenotypes or the weight of animals. However, little data describe the age effect on the different measurements. In the present paper, 477 Bactrian camels (7–180 months old) were measured (length of the head, length and circumference of the neck, height at the withers, girth circumference, length of the front leg, and length of the body), and their growth was modeled by comparing different equations, the most convenient being the beta growth equation. In addition, the differences in body measurements of adult Bactrian camels between farms were tested by variance analysis, and multivariate analyses were used for identifying homogeneous clusters of camels according to their body measurements. The sampled animals were from different regions of the country. The significant relationships between cluster and region support the idea of racial differentiation. Body condition scoring is widely used in farm animals as an indicator of their feeding, health, and welfare status. If a body condition score is available for dromedaries, there is no specific grid for the Bactrian camel. Starting from typical examples taken from photos in different conditions, including extreme ones, a representation of a scoring system of 6 points from very emaciated (score 0) to overweight Bactrian camel (score 5) was proposed in the form of drawings from the right side, back, and three-quarter rear. To complete the drawings, a descriptive grid was built as a base for training stakeholders in relation to Bactrian camel farm management. However, the seasonal change in the fleece abundance, the variability of the humps' shape, and the presence of crossbreeding with dromedary camels require adapting the scoring accordingly
Peuples Autochtones, Communautés. Locales et forêts tropicales : plus de justice pour plus d'impact
Get PDFRevendiquer la pleine prise en compte des droits, des savoirs, des capacités et des aspirations des Peuples Autochtones et Communautés Locales (PA CL) à propos des écosystèmes forestiers qui les entourent ne constitue pas une garantie pour leur préservation. C'est avant tout une question de justice sociale. Cette note appelle ainsi à un renversement de perspective : faire de la reconnais- sance et de la protection des droits des PA CL une priorité, indépendamment de leur contribution environnementale et climatique. L'application d'une plus grande justice sociale nécessite une meilleure représentation des PA CL dans les instances de décision, quelles que soient leurs échelles. De nom- breux efforts sont faits pour renforcer les réseaux existants ou en déployer de nouveaux, mais beaucoup reste à faire pour que ces acteurs connaissent et s'impliquent dans ces dispositifs. Du chemin reste également à parcourir pour parvenir à un débat rééquilibré, véritablement co-construit, dépassant les approches descendantes ou symboliques. Plus de justice sociale repose enfin sur un effort de finance- ment vers des initiatives répondant aux besoins des PA CL, même si celles-ci ne visent pas directement et immédiate- ment la protection des forêts. Des financements adaptés aux besoins et capacités des populations locales et l'exis- tence de chaînes de valeur équitables et durables peuvent ainsi constituer des leviers puissants pour favoriser une vision et une pratique partagées des forêts
Evaluation of antioxidant-surfactant interactions using size distribution Taylor dispersion analysis: Measuring antioxidant partitioning and size of native-state micelles
Get PDFIn food emulsions, excess surfactants often lead to the formation of micelles, which play a critical role in modulating the localization and efficacy of antioxidants. The interactions between antioxidants and micelles can either enhance or impair antioxidant function. Despite this importance, methodologies to study these interactions in native-state micelles remain limited. In this study, we employed Size Distribution - Taylor Dispersion Analysis (SD-TDA), a fast and absolute technique for measuring diffusion coefficients and thus hydrodynamic radii, to investigate antioxidant–surfactant interactions in sodium dodecyl sulfate (SDS) micelles, both below and above its critical micelle concentration. Studied antioxidants include α-tocopherol, curcumin, gallic acid, propyl gallate, and octyl gallate. The results revealed distinct behaviors: while gallic acid remained in the aqueous phase regardless of SDS presence, octyl gallate appeared to co-micellize with SDS. Curcumin was fully incorporated into SDS micelles, with micelle size increasing from 4.68 ± 1.52 nm to 6.92 ± 0.79 nm at the maximum loading capacity of 3.57 ± 0.05 mM curcumin with 20 mM SDS. α-Tocopherol also localized within SDS micelles; however, above 2.5 mM, three distinct populations were identified using SD-TDA—free tocopherol in water, tocopherol in small micelles, and swollen SDS micelles. Unlike Dynamic Light Scattering, SD-TDA successfully resolved these populations and provided quantitative insights into their size and α-tocopherol partitioning. These findings highlight the potential of SD-TDA as a powerful tool for studying antioxidant partitioning and micellar interactions, opening the way for more in-depth investigations into the role of micelles in antioxidant efficiency in emulsified systems
Wild boar trade and African swine fever risk of introduction into new territories: A quantitative release assessment with retrospective data of wild boar shipments to France and Spain (2010-2017)
Get PDFWild boar (WB) (Sus scrofa) farming and trade in EU countries consistently developed at the end of the last century, primarily for repopulating hunting estates within the sport hunting industry. Since the introduction of African swine fever (ASF) in the Caucasus in 2007 and its subsequent spread from Eastern to Central Europe, international WB trade increased the risk of ASF introduction into new territories. In order to prevent such events, the EU veterinary authorities decided to ban WB trade in June 2018. In our study, we documented retrospective WB trade movements to France and Spain between 2010 and 2017, and used this data to undertake a quantitative risk assessment for ASF introduction resulting from those shipments. A total of 127 trade events introducing live WB into France (n = 93) and Spain (n = 34) from Eastern EU countries were recorded between 2010 and 2017, encompassing a total of 5567 animals. Hungary was the main exporter to both countries while Poland was the main exporter to France. The highest annual risk of ASF release was related to shipments from Poland to France after 2014 coinciding with an epidemic phase of ASF in that country. During the same period, the risk of ASFV introduction from Hungary to France was much smaller but gradually increased, coinciding with outbreaks in adjacent Ukraine territory during 2015 onward. Despite no outbreaks in France nor Spain were detected to date, quantified values of ASF introduction risk into Western Europe were very high, suggesting that prohibiting international WB trade in 2018 was well justified. Our study highlights the relevance to monitor and supervise more closely legal wildlife production within the EU countries. Our results are an interesting example on how to use trade data to design and implement risk reduction strategies to reduce the spread of pathogens in the wildlife trade sector
Crimean-Congo hemorrhagic fever virus circulation in wild European rabbits, Portugal, 2018-2023
Get PDFCrimean-Congo hemorrhagic fever virus is considered a public health risk in southwestern Europe. We surveyed serum samples from 667 European rabbits across Portugal, a rabbit species known to host immature Hyalomma lusitanicum ticks. We found low levels of virus antibodies (>1%), with a localized cluster reaching 5.77% in southern populations
Improving dual purpose value of photoperiod-sensitive sorghum in Mali using brown midrib and juicy traits
Get PDFThe increasing fodder demand in West African livestock production systems has prompted sorghum (Sorghum bicolor (L.) Moench) breeding programmes to develop dual-purpose varieties that produce grain for human consumption and fodder for livestock. This study examines the possibility of improving sorghum stalks quality of a photoperiodic variety, using two genes, which are known to improve straw digestibility by livestock. Three near-isogenic lines carrying either the brown midrib (bmr-12) allele, the juiciness (d) allele, or both alleles, were developed from an elite photoperiodic dual-purpose variety. Trials with three sowing dates were conducted from 2020 to 2021. Phenology, morphology and stem chemical composition were measured. Lines carrying bmr-12 allele showed a greater reduction in stem lignin content, than those carrying the 'd' allele alone. The two alleles have no cumulative effect on lignin content or stalk digestibility. Delayed sowing improved stalk digestibility significantly, but it is not an appropriate agronomic solution as it drastically reduces crop growth. The utilisation of the brown midrib trait appears to be a promising method of enhancing stalk digestibility; while preserving the climate adaptation provided by photoperiodism. These results pave way for new dual-purpose sorghum varieties in sub-Saharan Africa, contributing to the intensification of peri-urban livestock production
Spatial modeling of the population dynamics of Anopheles mosquitoes in Madagascar
Get PDFBackground: Malaria, whose parasites are transmitted by Anopheles mosquitoes, remains a major public health burden in Madagascar despite the control measures led by the National Malaria Control Program. Understanding the population dynamics of Anopheles mosquitoes is therefore essential to optimize malaria surveillance and control. This study aimed to develop a model incorporating environmental, climatic and agricultural determinants of Anopheles abundance to predict their spatiotemporal distribution. Methods: We developed a model of spatiotemporal dynamics for four Anopheles species, vectors of malaria parasite in Madagascar: Anopheles arabiensis, Anopheles coustani, Anopheles funestus and Anopheles gambiae. This model was based on the life cycle of Anopheles and accounted for both the aquatic and aerial phases of their development. It used a system of differential equations to estimate the number of Anopheles mosquitoes at each stage of development. The Ocelet language, dedicated to the modeling of spatial dynamics, was used to produce simulations based on climate and environmental data. The model explicitly integrates the agricultural calendar to adjust the environmental carrying capacity of larval habitats. Model outputs were validated with entomological data collected in Vohimasy (Farafangana districts, 2014–2017). Results: 24 simulation outputs, from three Anopheles species and eight sites, were obtained and the validation revealed a significant correlation between field observations and model predictions: the correlation coefficients obtained ranged from 0.70 to 0.76. The predicted abundance of host-seeking Anopheles varied seasonally influenced by precipitation, temperature and environmental carrying capacity. The model exhibited robustness across sites with diverse climates and accurately reproduced interannual dynamics. The integration of the agricultural calendar significantly reduced the overestimation of the density of host-seeking adult females. Conclusion: The developed Anopheles dynamics model provides a valuable tool for predicting mosquito abundance and distribution over time and space. It correctly predicted the abundance at villages with contrasting climates and reproduced interannual dynamics well. A distinctive aspect of this work lies in the explicit integration of seasonal agricultural practices into the estimation of larval habitat availability. This allows for a more accurate and transferable modeling of Anopheles population dynamics
Projet MAKIS : Quelques acquis des ateliers précédents, fiche mémo
Get PDFLe projet MAKIS soutient l'innovation agricole à Madagascar en favorisant le renforcement de capacités des acteurs impliqués dans l'accompagnement de l'innovation agricole pour co-concevoir et diffuser des pratiques agricoles durables et adaptées aux réalités locales
Dairy farms at an advanced stage in their agroecological transition show higher environmental and socio-economic performance
Get PDFIn Burkina Faso, the growing demand for milk prompts dairy farmers to pursue solutions that improve their production while maintaining profitability and sustainability. This study aimed to analyse the link between the level of agroecological transition achieved by dairy farms in the Bobo-Dioulasso milkshed area and their multidimensional performance. To address this issue, 204 dairy farms were assessed in the Bobo-Dioulasso milkshed area according to their level of progress in the agroecological (AE) transition, using the Holistic Localised Performance Assessment for Agroecology (HOLPA) tool. A typology of the dairy farms was produced according to their level of progress in the AE transition. Averaged scores for all questions in the HOLPA tool relating to the 13 principles of agroecology were used to rate each farm on a 5-point Likert scale, from 1 (Non-AE) to 5 (Very Strong AE). Performance was then compared according to these score levels. Results indicate that the dairy farms studied are mostly at the beginning (Non-AE: 7%, Weak AE: 54%, Moderate AE: 33%, and Strong AE: 6%) of their AE transition. Our findings suggest that dairy farms which have adopted more advanced AE practices demonstrate improved environmental, social and economic performance compared to conventional or less transitioned farms. The most AE dairy farms stand out on several key performance indicators. In terms of environmental performance, the most AE dairy farms achieve higher scores for crop diversity and natural resource and land management. In terms of social performance, the most AE dairy farmers share more knowledge about agroecology and natural resources, report higher levels of household satisfaction, and perceive trade associations as efficient. In terms of economic performance, the most AE dairy farms enjoy more stable and diversified income streams, which may reflect their greater resilience. With regard to agronomic performance, the most AE dairy farms perform better in terms of organic manure and fodder production. However, heavy reliance on labor and low crop productivity (e.g., for maize, sorghum, millet, rice, and cowpea) have been identified as key challenges to the AE transition and the sustainability of dairy farms. The findings of this study justify the implementation of several policy measures to support farmer training in AE on fodder and organic manure production, and natural resources management, to guaranty a better access to forages seeds and agricultural equipment to manage manure production, to increase the skills of farmers community in collective natural resources management in order to strengthen and accelerate the AE transition and enhance the resilience of the dairy sector in Burkina Faso. This study provides robust evidence to help improve public policy, guide dairy industry strategies, and support the agroecological transition in the Bobo-Dioulasso milkshed area