10 research outputs found
Typology, management and smallholder farmer-preferred traits for selection of indigenous goats (Capra hisrcus) in three agro-ecological zones in the Democratic Republic of Congo
The present study aimed to assess the typology, production management, and smallholder farmer-preferred traits in selecting indigenous goats in three agro-ecological zones (AEZs) in the Democratic Republic of Congo (DR Congo). Based on a structured survey, baseline data were recorded on 320 adults and unrelated does from 202 goat farms. Hierarchical clustering on principal components revealed three clusters in the goats studied well distinguished by double and triple kidding. Prolific goats mostly clustered into cluster two and three more represented by goats of South Kivu while 82.69% of goats in Tshopo were clustered into cluster one characterized by low reproductive performances. The Canonical Discriminant Analysis revealed that the body length was an important variable both to discriminate and to classify goats from the three AEZs. Goats from Kinshasa and South Kivu were not distanced while large distance was observed between goats from Kinshasa and Tshopo (F-stat, p < 0.001). While not subjected to any good management practices, goats were considered as a source of income and saving method in smallholder farmers' households. Adaptability, resistance to disease and prolificacy were preferred traits by farmers in selecting goats. These results give the first step in the decision-making towards goat improvement in DR Congo
Typologie des Exploitations Agricoles Familiales et Technologie de Rouissage de Manioc : Cas des Exploitations de la Commune de Maluku, en République Démocratique du Congo
L’objectif de cette étude est l’élaboration d’une typologie des exploitations agricoles productrices du manioc dans la commune de Maluku, dans la périphérie de Kinshasa en République Démocratique du Congo. Les critères choisis sont : les caractéristiques socioéconomiques (Type de main-d’œuvre, appartenance à un groupe des producteurs et le type de contraintes à la production) ; les caractéristiques liées à la technologie de production du manioc (superficie emblavée, matériels de labour et le type de matériel végétal) ; les caractéristiques liées à la technologie de transformation du manioc (mode de rouissage, durée du rouissage et rendement en cossettes) et le village. Les données ont été collectées par enquête sur 344 exploitations agricoles œuvrant dans 6 villages. La typologie a été réalisée grâce à une ACM et une CAH. Les résultats de l’étude ont permis de regrouper les producteurs de manioc en trois types sur base des variables retenues. Les résultats révèlent 3 types d’exploitations agricoles. Avec le village, le type de contraintes, la productivité en cosette, le type de la main-d’œuvre et le type de matériel végétal comme les caractéristiques dominantes du premier axe de la typologie et le mode et la durée de rouissage comme caractéristiques dominantes du deuxième axe.
The objective of this study is to develop a typology of cassava-producing farms in the Maluku area, on the outskirts of Kinshasa in the Democratic Republic of Congo. The criteria chosen are: socio-economic characteristics (type of workforce, membership of a group of producers and type of production constraints); characteristics related to cassava production technology (exploited area, plowing equipment and type of plant material); the characteristics linked to the cassava processing technology (retting method, retting duration and chip yield) and the village. The data was collected by survey on 344 farms operating in 6 villages. The typology was made thanks to an ACM and finalized by a CAH. The results of the study made it possible to group cassava producers into three types on the basis of the variables retained. The results reveal 3 types of farms. With the village, the type of constraints, the productivity in cosette, the type of labor and the type of plant material as the dominant characteristics of the first axis of the typology and the mode and duration of retting as the dominant characteristics of the second axis
Haplotype analysis of the mitochondrial DNA d- loop region reveals the maternal origin and historical dynamics among the indigenous goat populations in east and west of the Democratic Republic of Congo
This study aimed at assessing haplotype diversity and population dynamics of three Congolese indigenous goat populations that included Kasai goat (KG), small goat (SG), and dwarf goat (DG) of the Democratic Republic of Congo (DRC). The 1169 bp d‐loop region of mitochondrial DNA (mtDNA) was sequenced for 339 Congolese indigenous goats. The total length of sequences was used to generate the haplotypes and evaluate their diversities, whereas the hypervariable region (HVI, 453 bp) was analyzed to define the maternal variation and the demographic dynamic. A total of 568 segregating sites that generated 192 haplotypes were observed from the entire d‐loop region (1169 bp d‐loop). Phylogenetic analyses using reference haplotypes from the six globally defined goat mtDNA haplogroups showed that all the three Congolese indigenous goat populations studied clustered into the dominant haplogroup A, as revealed by the neighbor‐joining (NJ) tree and median‐joining (MJ) network. Nine haplotypes were shared between the studied goats and goat populations from Pakistan (1 haplotype), Kenya, Ethiopia and Algeria (1 haplotype), Zimbabwe (1 haplotype), Cameroon (3 haplotypes), and Mozambique (3 haplotypes). The population pairwise analysis (F(ST) ) indicated a weak differentiation between the Congolese indigenous goat populations. Negative and significant (p‐value <.05) values for Fu's Fs (−20.418) and Tajima's (−2.189) tests showed the expansion in the history of the three Congolese indigenous goat populations. These results suggest a weak differentiation and a single maternal origin for the studied goats. This information will contribute to the improvement of the management strategies and long‐term conservation of indigenous goats in DRC
Haplotype analysis of the mitochondrial DNA d-loop region reveals the maternal origin and historical dynamics among the indigenous goat populations in east and west of the Democratic Republic of Congo
This study aimed at assessing haplotype diversity and population dynamics of three Congolese indigenous goat populations that included Kasai goat (KG), small goat (SG), and dwarf goat (DG) of the Democratic Republic of Congo (DRC). The 1169 bp d-loop region of mitochondrial DNA (mtDNA) was sequenced for 339 Congolese indigenous goats. The total length of sequences was used to generate the haplotypes and evaluate their diversities, whereas the hypervariable region (HVI, 453 bp) was analyzed to define the maternal variation and the demographic dynamic. A total of 568 segregating sites that generated 192 haplotypes were observed from the entire d-loop region (1169 bp d-loop). Phylogenetic analyses using reference haplotypes from the six globally defined goat mtDNA haplogroups showed that all the three Congolese indigenous goat populations studied clustered into the dominant haplogroup A, as revealed by the neighbor-joining (NJ) tree and median-joining (MJ) network. Nine haplotypes were shared between the studied goats and goat populations from Pakistan (1 haplotype), Kenya, Ethiopia and Algeria (1 haplotype), Zimbabwe (1 haplotype), Cameroon (3 haplotypes), and Mozambique (3 haplotypes). The population pairwise analysis (F-ST) indicated a weak differentiation between the Congolese indigenous goat populations. Negative and significant (p-value <.05) values for Fu's Fs (-20.418) and Tajima's (-2.189) tests showed the expansion in the history of the three Congolese indigenous goat populations. These results suggest a weak differentiation and a single maternal origin for the studied goats. This information will contribute to the improvement of the management strategies and long-term conservation of indigenous goats in DRC
Évaluation de la durabilité des exploitations maraîchères au Sud-Kivu (Est de la République Démocratique du Congo)
Le maraîchage est actuellement un secteur où certaines pratiques d’agriculture moderne comme la culture pure et l’utilisation des produits de synthèse se développent, mais sont de plus en plus questionnées. L’évaluation de la durabilité de ces pratiques n’a pas encore fait l’objet d’études dans les régions montagneuses du Sud-Kivu, à l’Est de la République démocratique du Congo. Pour y remédier, la durabilité de 368 unités de production maraîchère choisies de manière aléatoire et stratifiée a été évaluée grâce à l’outil « Indicateur de la durabilité de la production maraîchère » (IPDM). Les résultats obtenus font ressortir trois types d’exploitations dont 44 % sont de grande taille, 52 % de taille moyenne et 5 % de petite taille. Il a été constaté que, sur un maximum de 100 points possibles, les exploitations de petite taille obtiennent des scores de durabilité de 60 %, 53 % et 57 % sur les trois dimensions respectives de la durabilité : agroécologique, socio-territoriale et économique. Sur toutes ces dimensions, les grandes exploitations n’atteignent pas 50 %. Ces résultats montrent que les grandes exploitations, plus modernes, sont cependant moins durables. Afin de pérenniser le maraîchage au Sud-Kivu, il apparaît donc nécessaire de promouvoir l’intensification écologique, la diversification intégrée et la promotion des intrants locaux auprès des différents types d’exploitation, et en particulier des plus grandes, engagées dans des techniques intensives mais peu durables
Volcanic activity controls cholera outbreaks in the East African Rift
International audienceWe hypothesized that Cholera (Vibrio cholerae) that appeared along Lake Kivu in theAfrican Rift in the seventies, might be controlled by volcano-tectonic activity, which, byincreasing surface water and groundwater salinity and temperature, may partly rule thewater characteristics of Lake Kivu and promote V. cholerae proliferation. Volcanic activity(assessed weekly by the SO2 flux of Nyiragongo volcano plume over the 2007–2012 period)is highly positively correlated with the water conductivity, salinity and temperature of theKivu lake. Over the 2007–2012 period, these three parameters were highly positively correlatedwith the temporal dynamics of cholera cases in the Katana health zone that border thelake. Meteorological variables (air temperature and rainfall), and the other water characteristics(namely pH and dissolved oxygen concentration in lake water) were unrelated to choleradynamics over the same period. Over the 2016–2018 period, we sampled weekly lake watersalinity and conductivity, and twice a month vibrio occurrence in lake water and fish. Theabundance of V. cholerae in the lake was positively correlated with lake salinity, temperature,and the number of cholera cases in the population of the Katana health zone. V. choleraeabundance in fishes was positively correlated with V. cholerae abundance in lakewater, suggesting that their consumption directly contaminate humans. The activity of thevolcano, by controlling the physico-chemical characteristics of Lake Kivu, is therefore amajor determinant of the presence of the bacillus in the lake. SO2 fluxes in the volcanoplume can be used as a tool to predict epidemic risks