Vulnerability and access to land in the commune of Diama

The issue of equal access of citizens to land remains a concern of public authorities to respond to issues related to household food security, especially in rural areas. Along the way, a legal and regulatory framework has been developed to give substance to the development options of the primary sector consisting of agriculture and livestock. However, the criteria identified in the context of the allocation of land in the national domain are sometimes biased due to considerations based on the social position of the person concerned. Indeed, the notion of capacity to be able to develop the land requested naturally excludes certain strata that do not meet the financial conditions required for such exploitation. According to our surveys, the category of people who find themselves in this situation is often made up of women, young people, the elderly and those with disabilities. However, there are a series of measures that would aim to restore the equality of citizens for the access and use of natural and land resources. Land projects and programs in collaboration with the State and rural communes make consideration of the gender aspect a component. This concern has enabled vulnerable groups to be better taken into account in the land allocation activities of the national domain at the level of the commune of Diama, notwithstanding the breakthrough of large-scale land acquisitions (ATE)

Le cactus Opuntia tuna (L.) Mill. et ses formes d’usage dans la zone des Niayes au Sénégal

Opuntia tuna est une espèce bien adaptée dans la zone des Niayes au Sénégal. Sa prolifération assez rapide est due en partie à une sous exploitation suscitant ainsi un envahissement de quelques espaces agropastoraux. Dans une perspective de valorisation et de meilleure gestion de l’espèce, cette présente étude a été conduite pour comprendre les formes d’usages et de gestion de la plante par les populations locales afin de la promouvoir pour renforcer leur résilience. L’étude a porté sur cinq villages de la zone nord des Niayes auprès de petits exploitants de maraichers. Des enquêtes qualitatives par entretiens et groupes de discussion ont été conduites. Elles ont porté sur le niveau de connaissance, les pratiques et usages connus du cactus, les contraintes liées à sa présence, les solutions adoptées ou envisagées et le niveau de perception sur sa valorisation. Les résultats ont révélé de nombreux usages de la plante et de ses produits. Plus de la moitié des personnes enquêtées utilise le cactus dans le domaine agricole. L’élevage, la pharmacopée et l’alimentation sont d’autres secteurs également concernés par l’usage du cactus. Les analyses ont montré que la plupart des personnes enquêtées (94%) admettent un degré d’envahissement très élevé de Opuntia tuna. Le niveau d’envahissement pourrait être liée à la zoochorie selon 38% des hommes et 33% des femmes. La bonne adaptation de l’espèce dans la zone serait également un facteur de prolifération selon 33% des hommes et 23 % des femmes. Afin de pallier la prolifération rapide du cactus les maraichers ont développé des stratégies de gestion telles que le brulis, la coupe et le dessouchage. Une meilleure gestion de cette espèce qui présente de nombreux usages pour les maraichers de la zone des Niayes est nécessaire. De tels usages de l’espèce, valorisés davantage pourrait contribuer de façon significative à la diversification des sources de revenus des communautés locales et au développement durable de la zone des Niayes

Evolution of the Pyrethroids Target-Site Resistance Mechanisms in Senegal: Early Stage of the Vgsc-1014F and Vgsc-1014S Allelic Frequencies Shift.

The evolution and spread of insecticide resistance mechanisms amongst malaria vectors across the sub-Saharan Africa threaten the effectiveness and sustainability of current insecticide-based vector control interventions. However, a successful insecticide resistance management plan relies strongly on evidence of historical and contemporary mechanisms circulating. This study aims to retrospectively determine the evolution and spread of pyrethroid resistance mechanisms among natural Anopheles gambiae s.l. populations in Senegal. Samples were randomly drawn from an existing mosquito sample, collected in 2013, 2017, and 2018 from 10 sentinel sites monitored by the Senegalese National Malaria Control Programme (NMCP). Molecular species of An. gambiae s.l. and the resistance mutations at the Voltage-gated Sodium Channel 1014 (Vgsc-1014) locus were characterised using PCR-based assays. The genetic diversity of the Vgsc gene was further analyzed by sequencing. The overall species composition revealed the predominance of Anopheles arabiensis (73.08%) followed by An. gambiae s.s. (14.48%), Anopheles coluzzii (10.94%) and Anopheles gambiae-coluzii hybrids (1.48%). Both Vgsc-1014F and Vgsc-1014S mutations were found in all studied populations with a spatial variation of allele frequencies from 3% to 90%; and 7% to 41%, respectively. The two mutations have been detected since 2013 across all the selected health districts, with Vgsc-L1014S frequency increasing over the years while Vgsc-1014F decreasing. At species level, the Vgsc-1014F and Vgsc-1014S alleles were more frequent amongst An. gambiae s.s. (70%) and An. arabiensis (20%). The Vgsc gene was found to be highly diversified with eight different haplotypes shared between Vgsc-1014F and Vgsc-1014S. The observed co-occurrence of Vgsc-1014F and Vgsc-1014S mutations suggest that pyrethroid resistance is becoming a widespread phenomenon amongst malaria vector populations, and the NMCP needs to address this issue to sustain the gain made in controlling malaria

The role of cultivated versus wild seeds in the diet of European turtle doves (Streptopelia turtur) across European breeding and African wintering grounds

Agricultural intensification is a major driver in species declines, with changes in land use resulting in widespread alteration of resource availability. An increase in anthropogenic food resources, alongside decreasing natural resources, has resulted in species undergoing dietary changes that can have important ecological consequences, particularly for declining species. Here we use high-throughput sequencing to analyze the diet of the migrant European turtle dove (Streptopelia turtur), a species that has experienced significant population decline throughout its European range. We analyze the diet of this species on both breeding and wintering grounds to gain an understanding of resource use throughout the annual cycle and compare areas of more and less intensive agriculture in western and eastern Europe, respectively. We examine associations with body condition, spatiotemporal variation and the source of food (wild or cultivated). We identified 121 taxonomic units in the diet, with significant variation across sampling seasons, and very little overlap between the breeding and wintering seasons, as well as high levels of cultivated food resources in the diet of turtle doves in both breeding and wintering grounds, with the highest proportion of wild seeds in the diet occurring in birds caught in Hungary, where agricultural intensity was lowest. We detected no association between body condition and the consumption of cultivated food resources. We demonstrate the importance of wild resources in birds on the wintering grounds as they approach migration, where body condition increased as the season progressed, concurrent with an increased consumption of wild seeds. These findings indicate the importance of habitats rich in wild seeds and the need to consider food availability on the wintering grounds, as well as the breeding grounds in turtle dove conservation strategies

Evolution of the Ace-1 and Gste2 Mutations and Their Potential Impact on the Use of Carbamate and Organophosphates in IRS for Controlling Anopheles gambiae s.l., the Major Malaria Mosquito in Senegal

Widespread of insecticide resistance amongst the species of the Anopheles gambiae complex continues to threaten vector control in Senegal. In this study, we investigated the presence and evolution of the Ace-1 and Gste2 resistance genes in natural populations of Anopheles gambiae s.l., the main malaria vector in Senegal. Using historical samples collected from ten sentinel health districts, this study focused on three different years (2013, 2017, and 2018) marking the periods of shift between the main public health insecticides families (pyrethroids, carbamates, organophosphates) used in IRS to track back the evolutionary history of the resistance mutations on the Ace-1 and Gste2 loci. The results revealed the presence of four members of the Anopheles gambiae complex, with the predominance of An. arabiensis followed by An. gambiae, An. coluzzii, and An. gambiae-coluzzii hybrids. The Ace-1 mutation was only detected in An. gambiae and An. gambiae-coluzzii hybrids at low frequencies varying between 0.006 and 0.02, while the Gste2 mutation was found in all the species with a frequency ranging between 0.02 and 0.25. The Ace-1 and Gste2 genes were highly diversified with twenty-two and thirty-one different haplotypes, respectively. The neutrality tests on each gene indicated a negative Tajima's D, suggesting the abundance of rare alleles. The presence and spread of the Ace-1 and Gste2 resistance mutations represent a serious threat to of the effectiveness and the sustainability of IRS-based interventions using carbamates or organophosphates to manage the widespread pyrethroids resistance in Senegal. These data are of the highest importance to support the NMCP for evidence-based vector control interventions selection and targeting

Feasibility of Onchocerciasis Elimination with Ivermectin Treatment in Endemic Foci in Africa: First Evidence from Studies in Mali and Senegal

The control of onchocerciasis, or river blindness, is based on annual or six-monthly ivermectin treatment of populations at risk. This has been effective in controlling the disease as a public health problem, but it is not known whether it can also eliminate infection and transmission to the extent that treatment can be safely stopped. Many doubt that this is feasible in Africa. A study was undertaken in three hyperendemic onchocerciasis foci in Mali and Senegal where treatment has been given for 15 to 17 years. The results showed that only few infections remained in the human population and that transmission levels were everywhere below postulated thresholds for elimination. Treatment was subsequently stopped in test areas in each focus, and follow-up evaluations did not detect any recrudescence of infection or transmission. Hence, the study has provided the first evidence that onchocerciasis elimination is feasible with ivermectin treatment in some endemic foci in Africa. Although further studies are needed to determine to what extent these findings can be extrapolated to other areas in Africa, the principle of onchocerciasis elimination with ivermectin treatment has been established