Ministère de l'Agriculture

Sterile Insect Technique (SIT) applications against major insect pests and disease vectors rely on the cost-effective production of high-quality sterile males. This largely depends on the optimal management of target pest colonies by maximizing the benefits provided by a genetically rich and pathogen-free mother colony, the presence of symbiotic microorganisms, and efficient domestication, mass-rearing, irradiation, and release processes. At the same time microbial (bacteria, fungi, microsporidia, and viruses) pathogen outbreaks should be minimized or eliminated, and the use of hazardous chemicals restricted. The optimization of the colony management strategies for different SIT target insects will ensure a standardized high-quality mass-rearing process and the cost-effective production of sterile males with enhanced field performance and male mating competitiveness. The aims of the Coordinated Research Project (CRP) were to develop best practices for insect colony management for the cost-effective production of high-quality sterile males for SIT applications against major insect pests and disease vectors through a multidisciplinary approach involving entomologists, geneticists, ecologists, microbiologists, pathologists, virologists, and mass-rearing experts.

Sentinel animals may play a key role in surveillance of zoonotic arbovirus circulation, particularly in developing countries with low levels of investment in health. This study aimed to assess the relevance of using dogs as sentinel animals for Rift Valley fever virus (RVFV) surveillance in Madagascar. Serological surveys were conducted on 513 dogs and 135 cattle in the Ifanadiana district. In addition, 486 human dry blood samples available from the same area were used. Serostatus against RVFV was determined using a competitive Enzyme-Linked Immunosorbent Assay (cELISA) for dog and cattle samples, and a Multiplex Bead Assay (MBA) for human samples. Serocatalytic models fitted to age-stratified serological data were developed to estimate the RVF force of infection (FOI) under several hypotheses, ranging from no relationship to proportional FOIs between humans, cattle, and dogs. Antibodies to RVFV were detected in 23 of 513 dogs (4.5%; 95% confidence interval (95% CI): [2.9 - 6.7]), in 86 of 486 humans (17.7%; 95% CI: [14.4 – 21.4]), and in 33 of 135 cattle (24.4%; 95% CI: [17.5 - 32.6]). Based on the deviance information criterion, the best supported model indicated that FOI in humans and cattle was proportional to FOI in dogs. Proportionality parameters were estimated at 2.6 (95% credible interval (95% CrI): [1.4 - 5.1]) for humans and 3.5 (95% CrI: [1.3 - 6.4]) for cattle. Our findings suggest that sampling dogs could be used to identify RVFV circulation in endemic areas, and infer the exposure of humans and cattle in these areas in Madagascar. This original result paves the way for an innovative surveillance method for RVFV in Madagascar and other endemic countries, but also for other arboviruses such as West Nile virus.

The Niger River is critical in providing water for the socio-economic activities and development of Bamako city. However, predicting future water supply and demand is challenging. Therefore, an approach capable of analysing water availability is necessary. This study aims to use the Water Evaluation And Planning (WEAP) software to forecast water availability, treatment scenarios, and the reuse of treated wastewater by 2030. Evaluating the future pollution of the river in Bamako, the simulated flow, Dissolved Oxygen (DO), and Biochemical Oxygen Demand (BOD) along the Niger River from 2017 to 2030 were compared with 2016 values. Notwithstanding the elevated water demand resulting from the accelerated urbanisation and industrialisation, the entire length of the Niger River in Bamako would be contaminated. Even though the water tends to improve downstream, a BOD concentration of 9.83mg/l will exceed the requirement of 5mg/l set by the European Commission's recommendation for surface water quality. The high BOD downstream indicates the river's weakening capacity for self-purification and points to a 0% water demand coverage by 2030. Contrary to irrigation needs, the river cannot be used for domestic purposes due to pollution. Establishing wastewater treatment systems will improve the reuse of treated wastewater and reduce pollution levels in the Niger River by 86%.

Tsetse flies are harmful to humans and animals through their bites and infestations. Their distribution depends on the presence of vegetation and forest patches, etc. Visiting resting places, hunting grounds, or breeding grounds is a means of contact between human, animal, and insect populations. It encourages host–vector encounters and thus pathogen exchanges among humans, wildlife, and the environment. Controlling these insects considerably reduces their nuisance and breaks the pathogen transmission chain. Knowledge of the diversity of tsetse species and the main determinants of their geographical distribution is necessary to effectively combat this scourge. This study was initiated to determine the distribution of tsetse flies and identify the main species currently present in Mali. The 4 regions endemic for trypanosomiasis in Mali (Kayes, Koulikoro, Sikasso and Ségou) were selected for capture. In each region, 10 captures sites were randomly selected. The captures occurred from March to December 2020. The traps were placed on the banks of watercourses, in galleries, and in the Savannah. They were installed for 48 h and renewed every 24 h. A total of 1353 tsetse flies were captured, including 270 in Kayes, 527 in Koulikoro, 554 in Sikasso, and 4 in Ségou (p = 0.009). Two riparian species were identified, and no Savannah species were recorded. Tsetse flies were heterogeneously distributed. All sites in the Sikasso region recorded the presence of at least one tsetse fly (100%), while distribution was 80, 40 and 30%, respectively, in the Koulikoro, Kayes, and Ségou regions. These results show that tsetse flies are still present in these regions, albeit with an uneven distribution. A positive correlation was established between diversity and environmental parameters (<0.05).

The diversity in genome resources is fundamental to designing genomic strategies for local breed improvement and utilisation. These resources also support gene discovery and enhance our understanding of the mechanisms of resilience with applications beyond local breeds. Here, we report the genome sequences of 555 cattle (208 of which comprise new data) and high-density (HD) array genotyping of 1,082 samples (537 new samples) from indigenous African cattle populations. The new sequences have an average genome coverage of ~30X, three times higher than the average (~10X) of the over 300 sequences already in the public domain. Following variant quality checks, we identified approximately 32.3 million sequence variants and 661,943 HD autosomal variants mapped to the Bos taurus reference genome (ARS-UCD1.2). The new datasets were generated as part of the Centre for Tropical Livestock Genetics and Health (CTLGH) Genomic Reference Resource for African Cattle (GRRFAC) initiative, which aspires to facilitate the generation of this livestock resource and hopes for its utilisation for complete indigenous breed characterisation and sustainable global livestock improvement.

Abstract Cassava is a staple food in over twenty African countries, including Gabon. However, current production cannot meet the needs of the Gabonese people. Studies are being carried out to find ways of increasing national production throughout the country. Our study of sixteen cassava genotypes planted in different agro-ecological zones of Gabon focuses on three quantitative variables: number of lobes per leaf, petiole length and plant height at the vegetative stage. This study was carried out to see which introduced cassava genotypes were adapted to environments with different rainfall levels.