South Benin Research Articles

Assessing sustainability in smallholder vegetable farms in Benin Republic: A matrix approach

This study aims to assess the level of sustainability in vegetable-based agrifood production systems in Benin and to propose actions to enhance sustainability, food safety, and year-round production in the vegetable production systems. Semi-structured interviews were conducted with 200 vegetable farmers in contrasting agroecological areas (with areas of extensive production of staples and intensive production of vegetables), using the “Indicateur de Durabilité des Exploitations Agricoles” (IDEA) framework (an on-farm sustainability index). Most of the surveyed vegetable farmers produced a wide range of crops, including leafy vegetables (amaranth, African eggplant, and African basil) and peppers, grown by more than 50% of the farmers. The average scores achieved by the vegetable farms regarding three dimensions of sustainability—ecological, social, and economic—were 35, 41, and 63, respectively, out of a maximum score of 100. All three sustainability dimensions of the vegetable farms were, on average, at a low level and improvements were needed for them to reach an acceptable standard. The vegetable farms located in the south of Benin had, on average, a higher sustainability score than those in the north: around 50% of vegetable farms in the south had a medium score, while the sustainability level of almost 75% of vegetable farms in the north was low. Interventions seeking to improve the sustainability of vegetable farms in Benin should focus on the promotion and adoption of eco-responsible practices that improve on-farm biodiversity, water conservation, and the effective allocation and management of land and labor, to mitigate the environmental impacts of vegetable production.

SARS-CoV-2 seroprevalence among Beninese pregnant women in the third year of the pandemic

BackgroundPregnant women are a vulnerable population to COVID-19 given an increased susceptibility to severe SARS-CoV-2 infection and pregnancy complications. However, few SARS-CoV-2 serological surveys have been performed among this population to assess the extent of the infection in sub-Saharan countries. The objectives of this study were to determine SARS-CoV-2 seroprevalence among Beninese pregnant women, to identify spatial seropositivity clusters and to analyse factors associated with the infection.MethodsA cross-sectional study including women in their third trimester of pregnancy attending the antenatal care (ANC) clinics at Allada (south Benin) and Natitingou (north Benin) was conducted. Rapid diagnostic tests (RDT) for detection of IgG/IgM against the SARS-CoV-2 spike protein were performed using capillary blood. Seroprevalence of SARS-CoV-2 antibodies and associations between SARS-CoV-2 serostatus and maternal characteristics were analyzed by multivariate logistic regression. Spatial analyses were performed using the spatial scan statistics to identify spatial clusters of SARS-CoV-2 infection.ResultsA total of 861 pregnant women were enrolled between May 4 and June 29, 2022. 58/861 (6.7%) participants reported having received COVID-19 vaccine. None of the participants had been diagnosed with COVID-19 during their pregnancy. SARS-CoV-2 antibodies were detected in 607/802 (75.7%; 95% CI 72.56%–78.62%) of unvaccinated participants. Several urban and rural spatial clusters of SARS-CoV-2 cases were identified in Allada and one urban spatial cluster was identified in Natitingou. Unvaccinated participants from Allada with at least one previous morbidity were at a three-times higher risk of presenting SARS-CoV-2 antibodies (OR = 2.89; 95%CI 1.19%-7.00%).ConclusionThree out of four pregnant women had SARS-CoV-2 antibodies, suggesting a high virus circulation among pregnant women in Benin, while COVID-19 vaccination coverage was low. Pregnant women with comorbidities may be at increased risk of SARS-CoV-2 infection. This population should be prioritized for COVID-19 diagnosis and vaccination in order to prevent its deleterious effects.Trial registrationNCT06170320 (retrospectively registered on December 21, 2023).

IgG and IgM responses to the Plasmodium falciparum asexual stage antigens reflect respectively protection against malaria during pregnancy and infanthood.

Plasmodium falciparum malaria is a public health issue mostly seen in tropical countries. Until now, there is no effective malaria vaccine against antigens specific to the blood-stage of P. falciparum infection. Because the pathogenesis of malarial disease results from blood-stage infection, it is essential to identify the most promising blood-stage vaccine candidate antigens under natural exposure to malaria infection. A cohort of 400 pregnant women and their infants was implemented in South Benin. An active and passive protocol of malaria surveillance was established during pregnancy and infancy to precisely ascertain malaria infections during the follow-up. Twenty-eight antibody (Ab) responses specific to seven malaria candidate vaccine antigens were repeatedly quantified during pregnancy (3 time points) and infancy (6 time points) in order to study the Ab kinetics and their protective role. Abs were quantified by ELISA and logistic, linear and cox-proportional hazard model were performed to analyse the associations between Ab responses and protection against malaria in mothers and infants, taking into account socio-economic factors and for infants an environmental risk of exposure. The levels of IgM against MSP1, MSP2 and MSP3 showed an early protective response against the onset of symptomatic malaria infections starting from the 18th month of life, whereas no association was found for IgG responses during infancy. In women, some IgG responses tend to be associated with a protection against malaria risk along pregnancy and at delivery, among them IgG3 against GLURP-R0 and IgG2 against MSP1. The main finding suggests that IgM should be considered in vaccine designs during infanthood. Investigation of the functional role played by IgM in malaria protection needs further attention.

First implementation of quality control procedures on selected X-ray machines in South of Benin

Abstract Introduction: The use of X-ray equipment for medical diagnostic radiography procedures has increased due to advances and complexity of radiological procedures. Achieving good image quality while keeping exposure of workers, public and patient exposure to an acceptable level has become a prerequisite for the radiology department in order to comply with best international practices. The aim of this study was to undertake quality control measurement of seven (7) diagnostic radiography equipment in the south of Benin, the first of its kind. Material and methods: Multifunction detector (Piranha) and beam alignment test tool were used to perform quality control tests on seven (7) X-ray units. The method used as well as the interpretation of the results was based on the American Association of Physicists in Medicine (AAPM), United States Food and Drug Administration (FDA), Healing Arts Radiation Protection (HARP), Institute of Physics and Engineering in Medicine (IPEM), International Atomic Energy Agency (IAEA) and Canadian Safety code 35 (S.C 35) recommendations. Results: The quality control results showed that all X-ray equipment investigated were within standard limits for accuracy of exposure time below 10 ms; reproducibility of kVp, exposure time and dose output; specific dose-kVp2 linearity; and specific dose-mAs linearity. Five (5) out of seven (7) diagnostic X-ray machines passed quality control tests such as X-ray beam alignment, exposure time above 10 ms and kVp accuracy. One (1) X-ray machine failed the quality control test of beam filtration at 70 kVp and above. Conclusions: The findings of this study have provided baseline data for other radiology departments to embark on similar QA/QC activities, and also explore options for optimization of patient dose. However, there is a need to extend the study to cover more diagnostic X-ray machines throughout the country. It is anticipated that this would ultimately assist in improving radiation protection and safety during medical diagnostic radiological procedures.

The main forest species encountered in southern and central Benin, West Africa.

The south of Benin, a country in West Africa, is still home to remnants of dense forests that benefit from a particularly rainy sub-equatorial climate, with annual rainfall of up to 1,200 mm. These forest ecosystems are an integral part of the West African forest block, which stretches from Liberia to Togo. However, despite their richness and ecological importance, these forests are unfortunately subject to strong human pressures, particularly from slash-and-burn agriculture, intensive logging and the growing urbanisation of coastal areas. Preserving these forests is crucial, however, as they are home to remarkable plant and animal biodiversity, with many endemic species. What's more, these forests play an essential role in regulating the local climate, protecting soil and water resources, as well as providing local populations with a vital source of energy wood, non-timber forest products and support for their traditional agricultural practices. Faced with these conservation challenges, identifying and characterising the main tree species found in the forests of southern and central Benin, forest species and their ecology is an essential prerequisite for implementing sustainable management and restoration strategies for these threatened forest ecosystems in southern Benin. This work aims to identify and draw attention to the different forest species, specially tree forest species present in southern and central Benin. The dataset provides information on forest species found in southern and central Benin, West Africa. This dataset is extremely useful for forestry research, as it focuses mainly on the various forest species of major importance. It can be used as a basis for characterising individuals or populations of species, based on their abundance in relation to anthropogenic pressure and changes in environmental conditions.These species are characteristic of forests and, above all, are of particular interest both to populations and to managers of protected areas. Field collections were initiated in 2007 as part of natural forest inventory work. The data collected have been completed by various field works that followed this work on forest species in southern Benin. The latest version of the dataset is publicly and freely accessible on the GBIF website at the address https://www.gbif.org/dataset/aff3a10a-a86b-4eff-98e4-d63f92fd6f7e.It should be noted that the fact that the collection and monitoring were carried out in southern Benin, a region known for its great diversity of species, over a period of 10 years making these data particularly relevant information to study the effects of climate change and human pressure on ecosystems in this area.

Evaluation and Prediction of Groundwater Quality in the Municipality of Za-Kpota (South Benin) Using Machine Learning and Remote Sensing

Evaluation and Prediction of Groundwater Quality in the Municipality of Za-Kpota (South Benin) Using Machine Learning and Remote Sensing

Impacts of intercropping on the major insect pests of <i>Jatropha curcas L.</i> in south of Benin

Jatropha curcas is an oleaginous plant whose seed yield is low. The present study aimed at evaluating is pests associated with J. curcas. In regards to the densities, Denticera near divisella density was obtained 0.85 larvae per plant in J. curcas in sole farming and 0.70, 0.61, 0.85 larvae respectively when intercropped with casava, maize and cowpea. When J. curcas was intercropped with cassava Stomphastis thraustica was the most encountered species with a density of 1.28 larvae per plant while 0.61 larvae density was encountered for intercropped with maize and 0.27 larvae density with cowpea against 0.43 larvae in mono culture. For J. curcas with maize, Aulacophora africana was the most abundant species with a density of 0.47 adult per plant. In the case of J. curcas with cowpea. D. nr divisella had the highest density of 0.85 larvae per plant. It was also shown that the grain yield of J. curcas depends of intercrop. The yields were from 591.75 ± 109.25kg / ha; 431.75 ± 92.50kg / ha; 252.50 ± 51.50kg / ha; 89.50 ± 43.00kg/ha respectively in pure farming of J. curcas, Jatropha intercropped with maize, cowpea or cassava respectively. Therefore, it is important to choose intercropping to reduce the density of pests in Jatropha crop.

Influence of white blood cells count on parasite density in Malaria in children aged 6 to 59 months in Benin

For many years, the treatment of malaria was based on clinical presumptive diagnosis, making its differential diagnosis with other causes of hyperthermia difficult. This drug pressure has led to the emergence of Plasmodium strains resistant to the most commonly used antimalarial drugs. This is why in 2004, the health authorities decided to revise the policy of malaria management by adopting a new strategy based on the rational use of artemisininbased combination therapies after the biological confirmation of suspected malaria cases. The biological diagnosis is an essential part of malaria management. The gold standard technique for diagnosis is the thick drop combined with the calculation of parasite density (PD), which is determined on the basis of the number of parasites counted in a microscopic field against a proposed standard number of leukocytes. The number of leukocytes used to calculate the parasite density should ideally be the actual number of leukocytes in the patient per cubic millimetre of blood. However, in the absence of the availability of a blood count at the time of the thick drop, an average number of 8 000 leukocytes/mm3 was used by the World Health Organisation (WHO) to estimate the parasite density. Nonetheless, in Benin the average number of leukocytes adopted by the National Malaria Control Programme (PNLP) is 6 000/mm3. The aim of our study was to determine the impact of the leukocyte count on the calculation of the parasite density in cases of uncomplicated malaria. The study was a cross-sectional study with an analytical aim and took place in 2 hospitals in Benin, the Klouékanmey zone hospital in the south of Benin and the Djougou health centre in the north. It involved a population of 476 children aged between 6 and 59 months who were seen in consultation and in whom the clinical diagnosis of simple Plasmodium falciparum malaria was suspected. Children aged between 6 and 59 months, weighing at least 5 kg, with an axillary temperature ≥ 37.5°C at the time of consultation or a history of fever in the last 24 hours or other symptoms pointing to the diagnosis of malaria were included. Infestation was mono-specific for Plasmodium falciparum. Informed consent was required from the child's parents or guardian. The criteria for non-inclusion in our study were the presence of at least one sign of malaria severity, signs of severe malnutrition or a febrile state related to underlying infectious diseases other than malaria. Thick blood count and haemogram were systematically performed in all included children. Parasite density was calculated according to 3 methods, first using a weighted leukocyte count of 6 000/mm3 recommended by the Benin National Malaria Control Programme (PNLP), then a leukocyte count of 8 000/mm3 recommended by the World Health Organisation and finally the patient's actual leukocyte count obtained from the blood count. It should be noted that these different samples were respectively taken on the day of inclusion in compliance with the conditions of the pre-analytical phase in force in our medical biology laboratory. At the end of our study, 313 children, i.e. 65.76% of our study population had a positive white blood cell count with a positivity rate of 62.14% in Djougou, i.e. 174 children, and 70.9% in Klouékanmey, i.e. 139 children. The average leukocyte count in these children was 11,580/mm3. Among them, 205 children had an abnormal white blood cell count, i.e. 17 cases of leukopenia (5.43%) and 188 cases of hyperleukocytosis (60.06%). Using successively the average number of 6 000 leukocytes/mm3 proposed by the Benin PNLP and that of 8 000 leukocytes/mm3 proposed by the WHO, the average parasite densities were respectively 47,943 and 63,936 trophozoïtes/µl against 92,290 trophozoïtes/µl when the real number of leukocytes of the patients was used for the calculation of the PD. By using an average of 6 000 leukocytes/mm3 for PD calculation, 60% of the calculated PDs were underestimated and 6% were overestimated. Using an average of 8 000 leukocytes/mm3 resulted in 49% of PD being underestimated and 15% being overestimated. The difference between the three calculation methods was considered statistically significant (p value <0.05). The use of 6 000 or 8 000 coefficients for the estimation of parasitaemia could lead to a significant underestimation of the parasite load.

Technological variations, microbial diversity and quality characteristics of maize ogi used for akpan production in Benin

Fermented maize starch, called ogi in Benin, is used for preparing akpan, a traditional yoghurt-like food that contributes to the food and nutrition security of its consumers. Current ogi processing technologies used by two socio-cultural groups of Benin, namely the Fon and the Goun, and aspects of the quality of the fermented starches were studied to assess the current state-of-the-art, explore changes in key product characteristics over time and identify priorities for follow-up research to increase product quality and shelf life. A survey on processing technologies was conducted in five municipalities in south Benin and samples of maize starch were collected, which were analysed after the fermentation required to obtain ogi. Four processing technologies were identified, two from the Goun (G1, G2) and two from the Fon (F1, F2). The main difference between the four processing technologies was the steeping procedure used for the maize grains. The pH of the ogi samples ranged between 3.1 and 4.2, with the highest values for G1 samples, which also contained relatively higher concentrations of sucrose (0.05–0.3 g/L) than F1 samples (0.02–0.08 g/L), and lower citrate and lactate concentrations (0.2–0.3 and 5.6–16.9 g/L, respectively) than F2 samples (0.4–0.5 and 14–27.7 g/L, respectively). Fon samples collected in Abomey were particularly rich in volatile organic compounds and free essential amino acids. Members of the genera Lactobacillus (8.6–69.3%), Limosilactobacillus (5.4–79.1%), Streptococcus (0.6–59.3%) and Weissella (2.6–51.2%) dominated the bacterial microbiota of ogi with a significant abundance of Lactobacillus spp. in Goun samples. Sordariomycetes (10.6–81.9%) and Saccharomycetes (6.2–81.4%) dominated the fungal microbiota. The yeast community of ogi samples mainly consisted of the genera Diutina, Pichia, Kluyveromyces, Lachancea and unclassified members of the Dipodascaceae family. Hierarchical clustering of metabolic data showed similarities between samples from different technologies at a default threshold of 0.05.No obvious trend in the composition of the samples’ microbial communities reflected the clusters observed for the metabolic characteristics. The results indicate that beyond the general impact of the use of Fon or Goun technologies on fermented maize starch, the individual contribution of processing practices warrants study, under controlled conditions, to determine the drivers of difference or similarity between maize ogi samples to further contribute to improving product quality and shelf life.

Correlation between Photovoltaic Energy Production and Certain Climate Parameters: Case Study in the Plateau Department in Southern Benin

The Plateau department, where the first 25 MWp grid-connected solar plant was installed, is also an industrial cement zone, with high-energy demand, located in the south of Benin. In this region, the equatorial climate oscillated between two dry and two rainy seasons, with a high relative humidity. This climate variability influences the electrical output of photovoltaic (PV) modules. The analysis of the impact of climatic parameters such as relative humidity, precipitation, wind speed, ambient temperature, sunshine, on the photovoltaic production becomes necessary to optimize the energy generation in such a region. The objective of this study is to quantify the dependency relationship that exists between the variability of these parameters and the PV power generation using Pearson correlation method. The daily data collected for each parameter during the period from January 2011 to December 2020 were processed with Python 3.7.10 language. The results showed that relative humidity, with an average value of 80.14%, is the climatic has the highest negative impact (correlation coefficient of -0.42) on the performance of PV modules. Thus, the design and operation of a PV plant in this area should consider this parameter, especially with dust deposits, to improve the production yield.

Spatiotemporal Variability of Extreme Rainfall in Southern Benin in the Context of Global Warming

Changes in the frequency and timing of extreme precipitation in southern Benin are assessed in the context of global warming. The peak-over-threshold (POT) is used for this purpose, with the six (06) year return period daily rainfall as the threshold over seventeen (17) weather stations between 1960 and 2018. The results show that the South Benin experienced extreme rainfall on many occasions between 1960 and 2018 with a nonuniform spatiotemporal distribution of this category of rainfall. No statistically significant trend in the frequency and variation of extreme rainfall intensities is revealed over the study period. Despite the low rate of extreme rainfall, the monthly trend is consistent with the bimodal rainfall regime in southern Benin. The global warming highlighted in its last decades in southern Benin is accompanied by a slightly upward trend in extreme rainfall compared to the period before 1990.

Current Consumption of Traditional Cowpea-Based Dishes in South Benin Contributes to at Least 30% of the Recommended Intake of Dietary Fibre, Folate, and Magnesium.

Regular consumption of legumes is recommended worldwide for its environmental and health benefits. Cowpea, the most frequently consumed pulse in West African countries, is rich in nutrients and health-promoting bioactive compounds. A one-week retrospective food frequency questionnaire was used to estimate the contribution of the cowpea-based dishes to the recommended nutrient intake (RNI), based on their consumption frequency, intake, and nutritional composition. Participants were 1217 adults (19-65 years) from three urban or rural areas in southern Benin. Out of all respondents, 98% reported that they usually consumed cowpea-based dishes. The mean consumption frequency was 0.1 to 2.4 times/week, depending on the type of cowpea-based dish. The mean amount consumed was 71 g and 58 g of seeds/adult/day in urban and rural areas respectively. The mean daily contribution of cowpea-based dishes to RNI was 15% for energy, 42% for fibre, 37% for magnesium, 30% for folate, 26% for protein, and just above 15% for zinc and potassium. Thus, such regular cowpea consumption should be maintained.

WASH and NTDs: Outcomes and lessons learned from the implementation of a formative research study in NTD skin co-endemic communities in Benin.

Neglected Tropical Diseases (NTDs) are a diverse group of bacterial, viral, parasitic and fungal diseases affecting people, most of whom live below the poverty threshold. Several control strategies are defined against these diseases, including chemotherapy and Water, Hygiene and Sanitation (WASH). This study assesses the effect of promoting hygiene and sanitation on soil-transmitted helminthiasis s and NTDs of the skin. It took place in the communes of Ze, Lalo, and Zangnanado, three municipalities located in the south of Benin. This is a formative research that took place in three phases. The first phase entailed a baseline informations and situational analysis of the state of hygiene and health, using soil-transmitted helminthiasis and wound hygiene practices as cases studies. In the second phase, interventions to promote improved hygiene and sanitation were implemented. The third phase was devoted to post-intervention evaluation. The situation analysis showed that the prevalence of soil-transmitted helminthiasis was 6.43 and 7.10% in the municipalities of Ze and Lalo, respectively. In the communes of Zangnanado, the most common wound management practices identified were: putting sand or ashes in the wounds to keep flies away, the use of medicinal plants and the application of powder from antibiotic capsules for wound dressing. The post-intervention evaluation showed a decrease in the prevalence of soil-transmitted helminthiasis from 6.43 to 1.19% in the municipality of Lalo and from 7.10 to 1.75% in the municipality of Ze. In the commune of Zangnanado, a significant shift in wound management practices was noted, which led to the healing of several chronic wounds. This research supports the evidence that WASH-based interventions are very important to tackle neglected tropical diseases NTDs in addition to specific diseases based interventions.

Qualitative analysis of the perceptions of rural communities about the use of awareness-raising videos in nutrition and health programs in Benin.

This cross-sectional study aims at analyzing the perceptions of mothers, community leaders, and nutrition/health care workers (NHCWs) about using videos in nutrition and health programs compared to posters. In total, we recruited 42 mothers, 39 community leaders, and 30 NHCWs from villages and local organizations in two rural districts in South Benin, Bopa, and Houéyogbé. Learning sessions on Dietary diversity and Hygiene and deworming were organized using posters and videos. Participants' opinions on pros and cons of videos and posters were collected using individual semi-structured interviews with NHCWs and focus group discussions with mothers and community leaders, then analyzed thematically. Results showed that videos were perceived as more adapted to rural communities than posters because they were in local languages, self-explanatory, appealing, and captivating. Videos also enabled the dissemination of standardized messages. Globally, participants better-understood messages from videos than from posters, especially when dealing with dynamic processes. However, the speed of video sequences allowed limited time for self-reflection and assimilation of certain messages. The absence of electricity and lack of equipment to play videos in villages are also major constraints on the use of videos in such settings. While videos are innovant communication tools that should be promoted to improve motivation and compliance in learnings, they should be preferably used as complements to traditional posters for optimized assimilation of messages.

Estimation of Thermodynamic Parameters for Better Conservation of Fresh Tomato (&amp;lt;i&amp;gt;Lycopersicum esculentum&amp;lt;/i&amp;gt;)

Knowledge of the state of water balance of agro-food products is an essential step in drying or storage operations for preservation. Our study made it possible to determine the thermodynamic parameters which influence the storage conditions of fresh tomatoes grown in the south of Benin; and to predict its hygroscopic behavior during post-harvest storage. The desorption isotherms obtained at 40℃, 50℃ and 60℃, by the static gravimetric method using saturated saline solutions, are compared with those of the theoretical models of Brunauer, Emmet and Teller (BET), SMITH, PELEG and Guggenheim-Anderson-Boer (GAB). An adjustment of the experimental points, on the theoretical models, was made thanks to the numerical method which exploits the fminsearch algorithm under the MATLAB software, version R2018a. The GAB model at 50℃ faithfully reproduces the experimental desorption curves for water activities from 5.5% to 82.3%. The net isosteric heat of sorption was determined using the Clausius-Clapeyron equation, it increases when the degree of dehydration of the product increases. The applied isokinetic theory and enthalpy-entropy compensation are consistent.

Geographic modeling of weighted regression of self-reported malaria cases associated with environmental risk factors in Benin during the rainy season

Background: Geographically Weighted Regression (GWR) is a technique applied to capture variation by calibrating a multiple regression model, which allows different relationships to exist at different points in space. With malaria elimination at the top of the health agenda, integrated action on all elements of the malaria system that contributes to improved knowledge and local capacity building for positive effects on the health of the local population is needed. Methods: Several variables were collected for 192 sampling points in 12 communes in Benin, one per department. A questionnaire was sent to the head of the household to analyze the impact of environmental factors on reported malaria cases. Numerous GIS classification software for spatial analysis, remote sensing, data analysis/modeling and GPS management, R and MGWR software were used for geographic modeling. Results: An abundance of malaria cases reported in crop areas than in non-crop areas and in rural areas than in urban areas. The Hot Spot Analysis shows the localities of South Benin and Malanville as priority issue areas with a remarkable increase in crop diversity favorable to malaria vector proliferation. The spatial autocorrelation z-score of 4.83653470763 shows that there is less than a 1% probability that this clustered pattern is the result of chance. Conclusion: The observed non-stationarity means that the relationship between the variables studied varies from location to location depending on the physical factors of the environment that are spatially auto-correlated. Environmental factors therefore influence the intensity of transmission, seasonality, and geographic distribution of malaria. With minimal funding, we plan to correlate these data with parasitological and entomological da.

Prospective multicentre study of host response signatures in neonatal sepsis in Sub Saharan Africa

Few biomarkers for sepsis diagnosis are commonly used in neonatal sepsis. While the role of host response is increasingly recognized in sepsis pathogenesis and prognosis, there is a need for evaluating new biomarkers targeting host response in regions where sepsis burden is high and medico-economic resources are scarce. The objective of the study is to evaluate diagnostic and prognostic accuracy of biomarkers of neonatal sepsis in Sub Saharan Africa. This prospective multicentre study included newborn infants delivered in the Abomey-Calavi region in South Benin and their follow-up from birth to 3 months of age. Accuracy of transcriptional (CD74, CX3CR1), proteic (PCT, IL-6, IL-10, IP-10) biomarkers and clinical characteristics to diagnose and prognose neonatal sepsis were measured. At delivery, cord blood from all consecutive newborns were sampled and analysed, and infants were followed for a 12 weeks’ period. Five hundred and eighty-one newborns were enrolled. One hundred and seventy-two newborns developed neonatal sepsis (29.6%) and death occurred in forty-nine infants (8.4%). Although PCT, IL-6 and IP-10 levels were independently associated with sepsis diagnosis, diagnostic accuracy of clinical variables combinations was similar to combinations with biomarkers and superior to biomarkers alone. Nonetheless, CD74, being the only biomarkers independently associated with mortality, showed elevated prognosis accuracy (AUC > 0.9) either alone or in combination with other biomarkers (eg. CD74/IP-10) or clinical criterion (eg. Apgar 1, birth weight). These results suggest that cord blood PCT had a low accuracy for diagnosing early onset neonatal sepsis in Sub Saharan African neonates, while association of clinical criterion showed to be more accurate than any biomarkers taken independently. At birth, CD74, either associated with IP-10 or clinical criterion, had the best accuracy in prognosing sepsis mortality.Trial registration Clinicaltrial.gov registration number: NCT03780712. Registered 19 December 2018. Retrospectively registered.

Assessment of the biodiversity of sacred forests in the Atlantic department in Southern Benin

In Benin, the sacred forests constitute vestiges of heavily anthropized primary forests. In order to assess the importance of plant biodiversity in the sacred forests of the Atlantic department in South Benin, a forest inventory was carried out in five islands of sacred forests (Hêkpazoun : 25 ha ; Avogbézoun, Sindomè, Ahouansêzoun et Assanmeyzoun : 10 ha each). Structural parameters were compared between forests with analysis of variance tests. The results obtained show that the specific richness of the woody plants varies from 6 species (sacred forest of Hêkpazoun) to 20 species (sacred forest of Avogbézoun) with good distribution of trees between the different species regardless of the sacred forest considered (diversity index of Shannon varying between 3.17 and 4.11). Regarding the dendrometric parameters, only the mean diameter varied significantly (Prob. &lt;0.05) from one sacred forest to another. The largest trees were observed in the sacred forests of Avogbézoun (60.75 cm) and Ahouansêzoun (58.96 cm) while the smaller trees were observed in the sacred forests of Assanmeyzoun (32.03 cm) and Sindomè (42.50 cm). C. mildbraedii, F. thonningii, T. prieurianna, D. guineense, V. doniana and T. scleroxylon were the main characteristic species of sacred forests. Although the structural features do not indicate an alarming degradation of these ecosystems, measures must be taken for their conservation.

Sexual Maturity Scale of the Swimming Crab Callinectes pallidus (Rochebrune, 1883) from Lake Nokoué in South Benin, West Africa

Aims: Reproductive parameters are important tools for the sustainable management of halieutic species in the water bodies of its exploitation. This study intends to characterize the sexual maturity scale of swimming crab Callinectes pallidus, perform testicular and ovarian structures in order to develop a specific maturity scale.&#x0D; Study Design: This study was carried out with macroscopic and microscopic observations of 394 specimens of crabs including 206 females and 188 males.&#x0D; Place and Duration of Study: The specimens used in this study were collected monthly from March to July 2018 from small scale fisheries of Lake Nokoué (Benin).&#x0D; Methodology: At the laboratory, each crab specimen is identified and its sex determined. Grids for describing each sexual maturity stage of the crab C. pallidus were developed based on the Zairon et al. (2015) scale. Histological sections of female and male gonads were analyzed in order to certify the different stages of sexual development noted from the macroscopic study.&#x0D; Results: Macroscopic analysis of external and internal anatomy and histological study of male and female gonads of C. pallidus allowed to establish a sexual maturity scale with 5 stages in females and 4 stages in males respectively. Macroscopic observations made with a binocular magnifying glass allowed to describe the characteristic features of the sexual development cycle of the species. The histological study confirmed the results of the macroscopic analysis. Significant difference was recorded between the mean oocytes diameters of the different oocyte development stages (p&lt;0.05).&#x0D; Conclusion: The outcomes of this constitute an important database for the assessment of the reproductive parameters of the species in the water bodies of its exploitation. The stages IV and V are the mature steps in the female development whereas the stages III and IV are that of the male. It is recommended to allow C. pallidus reach the sexual maturity size (5,95 cm for female and 6,38 cm for male) before their exploitation to ensure the sustainable management of the species.

Characterization of a West African Coastal Lagoon System: Case of Lake Nokoué with Its Inlet (Cotonou, South Benin)

The purpose of this work was to investigate the physical and chemical dynamics of Lake Nokoué for its efficient management. For this purpose, two sampling campaigns per month from five stations (North, South, Central, East and West) were conducted for a period of one year (November 2020 to November 2021). Physic and chemical parameters (temperature, salinity, depth, water transparency, pH, dissolved oxygen and total dissolved solids) were measured and wet substrate samples were collected to study the granulometry. Data analysis revealed that Lake Nokoué is mainly affected by two regimes: flooding and low water. Flooding, which is not directly related to rainfall, did not begin until one month after the major rainy season in June. The sources that contributed to the flooding of Lake Nokoué were the freshwater tributaries coming mainly from the Ouèmé River and the flow of the Sô River from August to November. The inflow of fresh water contributed to the decrease in salinity and transparency of the lake from the east to the south. During the low water period (from December to July), Lake Nokoué is characterized by an increase in salinity and transparency from the south to the northeast due to the massive intrusion of sea water into the lake. The highest dissolved oxygen levels are observed in the south and center (5.92 ± 0.46 mg/L) while it varies greatly in the north and west (Eichhornia crassipes concentration zone) during flooding. The average annual depth of Lake Nokoué was 1.47 ± 0.66 m with an average annual pH of 6.85 ± 0.56.