Effets des pratiques agroécologiques sur l’efficacité du système productif des producteurs maraîchers au sud du Bénin

La production maraîchère au Bénin est associée à l’usage des intrants chimiques pour améliorer les rendements. Mais face aux risques environnementaux qui pèsent sur le milieu de production, il est nécessaire de produire plus écologique. L’objectif de cette étude est d’évaluer l’effet des pratiques agroécologiques sur l’efficience du système productif des maraîchers. A cet effet, une base de données du Centre VaLDERA renseignant sur les pratiques agricoles, comptes et résultats d‘exploitation de 197 producteurs des villes de Cotonou, Sèmè-kpodji et Ouidah en 2014 a été analysée. Une analyse en composante principale (ACP) a permis d’identifier des méta-variables : niveau d’utilisation d’engrais, pratiques agroécologiques et caractéristiques sociodémographiques. Ensuite une regression linéaire multiple log-log a permis d’identifier les variables : quantité de fientes, quantité de NPK utilisées, comme les principaux déterminants de l’efficience des producteurs. Les variables diversité écologique, association culturale, rotation sont faiblement corrélées à l’efficience. Il urge de former les producteurs sur les types de rotation qui puissent améliorer leur niveau de productivité et la qualité de leur production, mais aussi de les sensibiliser à l’usage des engrais organiques pour assurer la durabilité de la production.   Vegetable production in Benin is associated with the use of chemical inputs to improve yields. However, given the environmental risks that weigh on the environment, it is necessary to produce in a more ecological way. The objective of this study is to evaluate the effect of agroecological practices on the efficiency of the market gardeners' production system. To this end, a database from the VaLDERA Centre providing information on the agricultural practices, accounts and operating results of 197 producers in the cities of Cotonou, Sèmè-kpodji and Ouidah in 2014 was analysed. A principal component analysis (PCA) identified meta-variables: level of fertiliser use, agroecological practices and socio-demographic characteristics. Then a multiple log-log linear regression identified variables: amount of manure, amount of NPK used, as the main determinants of producer efficiency. The variables ecological diversity, crop association and rotation are weakly correlated with efficiency. There is an urgent need to train producers on the types of rotation that can improve their level of productivity and the quality of their production, but also to make them aware of the use of organic fertilisers to ensure the sustainability of production

Pratiques d’élevage avicole au Sud-Bénin (Afrique de l’Ouest) et impacts sur l’hygiène des fumiers produits

La précarité des systèmes d’élevage avicole en Afrique de l’Ouest peut favoriser l’introduction de germes pathogènes dans les élevages. Or, les fumiers de volaille sont très utilisés dans le maraîchage au Bénin. Par conséquent, le transfert de germes des fumiers vers les produits maraîchers est à craindre. L’objectif de cette étude était d’explorer les pratiques d’élevage avicole dans le département de l’Atlantique (Sud-Bénin). Au total, 78 fermes avicoles ont été visitées. Un questionnaire a été administré aux producteurs. La plupart d’entre eux (82,1%) ont rapporté qu’ils se lavent toujours les mains avant d’entrer dans les poulaillers. Sur les fermes disposant de pédiluves, 15,4% des producteurs ont avoué ne pas toujours y passer avant d’accéder aux poulaillers. Un seul producteur a rapporté qu’il ne fait pas la décontamination terminale des bâtiments. L’analyse du fumier prélevé sur l’une des fermes a révélé la présence de quantités très élevées de germes aérobies mésophiles d’Escherichia coli, de Clostridium perfringens et de coliformes thermotolérants. Ces résultats microbiologiques montrent que les pratiques d’hygiène en aviculture sont encore peu satisfaisantes au Bénin.© 2015 International Formulae Group. All rights reserved.Mots clés: Élevage avicole, bonnes pratiques, risques microbiologiques, hygièneEnglish Title: Poultry farming practices in South-Benin (West Africa) and impacts on the manures hygieneEnglish AbstractIn general, the poultry farming systems in West Africa are less sophisticated. These systems can be sources of carrying out of pathogens to the farms. But, in Benin Republic, poultry manures are widely used in market gardening. So, the transfer of pathogens from manures to vegetables is worrisome. This research aimed  at investigating the poultry farming practices in the Atlantic division (South-Benin). In total, 78 poultry farms were visited. A questionnaire was handed out to the producers. Most of them (82.1%) reported that they always wash their hands before entering poultry houses. On the farms where footbaths were present, 15.4% of producers declared that they do not always pass through it before entering poultry houses. Only one producer reported that he does not do the final decontamination of the houses. Analysis of the manure taken from one of the farms showed very high amounts of aerobic mesophile bacteria, of Escherichia coli, of Clostridium perfringens and thermotolerant coliforms. These microbiological results show that satisfying hygiene practices in poultry farming are still lacking in Benin.© 2015 International Formulae Group. All rights reserved.Keywords: Poultry farming, good practices, microbiological risks, hygien

Acquisition of natural humoral immunity to <i>P. falciparum</i> in early life in Benin:impact of clinical, environmental and host factors

To our knowledge, effects of age, placental malaria infection, infections during follow-up, nutritional habits, sickle-cell trait and individual exposure to Anopheles bites were never explored together in a study focusing on the acquisition of malaria antibody responses among infants living in endemic areas. Five hundred and sixty-seven Beninese infants were weekly followed-up from birth to 18 months of age. Immunoglobulin G (IgG), IgG1 and IgG3 specific for 5 malaria antigens were measured every 3 months. A linear mixed model was used to analyze the effect of each variable on the acquisition of antimalarial antibodies in 6- to 18-month old infants in univariate and multivariate analyses. Placental malaria, nutrition intakes and sickle-cell trait did not influence the infant antibody levels to P. falciparum antigens. In contrary, age, malaria antibody levels at birth, previous and present malaria infections as well as exposure to Anopheles bites were significantly associated with the natural acquisition of malaria antibodies in 6- to 18-month old Beninese infants. This study highlighted inescapable factors to consider simultaneously in an immuno-epidemiological study or a vaccine trial in early life

Association of IL-4 and IL-10 maternal haplotypes with immune responses to P. falciparum in mothers and newborns

Abstract Background: Particular cytokine gene polymorphisms are involved in the regulation of the antibody production. The consequences of already described IL-4, IL-10 and IL-13 gene polymorphisms on biological parameters and antibody levels were investigated among 576 mothers at delivery and their newborns in the context of P. falciparum placental malaria infection. Methods: The study took place in the semi-rural area of Tori-Bossito, in south-west Benin, where malaria is meso-endemic. Six biallelic polymorphisms were determined by quantitative PCR using TaqMan W Pre-Designed SNP Genotyping Assays, in IL-4 (rs2243250, rs2070874), IL-10 (rs1800896, rs1800871, rs1800872) and IL-13 (rs1800925) genes. Antibody responses directed to P. falciparum MSP-1, MSP-2, MSP-3, GLURP-R0, GLURP-R2 and AMA-1 recombinant proteins were determined by ELISA. Results: The maternal IL-4 −590 *T/IL-4 +33 *T haplotype (one or two copies) was associated with favorable maternal condition at delivery (high haemoglobin levels, absence of placental parasites) and one of its component, the IL-4 −590 TT genotype, was related to low IgG levels to MSP-1, MSP-2/3D7 and MSP-2/FC27. Inversely, the maternal IL-10 −1082 AA was positively associated with P. falciparum placenta infection at delivery. As a consequence, the IL-10 −819 *T allele (in CT and TT genotypes) as well as the IL-10 −1082 *A/IL-10 −819 *T/IL-10 −592 *A haplotype (one or two copies) in which it is included, were related to an increased risk for anaemia in newborns. The maternal IL-10 −1082 AA genotype was related to high IgG levels to MSP-2/3D7 and AMA-1 in mothers and newborns, respectively. The IL-13 gene polymorphism was only involved in the newborn&apos;s antibody response to AMA-1. Conclusion: These data revealed that IL-4 and IL-10 maternal gene polymorphisms are likely to play a role in the regulation of biological parameters in pregnant women at delivery (anaemia, P. falciparum placenta infection) and in newborns (anaemia). Moreover, IL-4, IL-10 and IL-13 maternal gene polymorphisms were related to IgG responses to MSP-1, MSP-2/3D7 and MSP-2/FC27 in mothers as well as to AMA-1 in newborns