Écologie alimentaire d’Euchilichthys guentheri (Mochokidés, Siluriformes) du Pool Malebo, fleuve Congo, République Démocratique du Congo

The feeding ecology of Euchilichthys guentheri (Schilthuis, 1891) of Malebo Pool (Congo River, Kinshasa, DRC) was studied between January 2008 and October 2010. The stomach contents of 243 individuals were analysed and a diet was characterized by a feeding index computed by combining the occurrences, the numerical and volume percentages of the items identified in the stomach contents. The study showed that this species has an herbivorous diet mainly composed of periphyton. The study did not find any statistical differences in the diet related to the size of the specimens, the site and the hydrological season. The dietary strategies developed by this species likely contribute to its coexistence with the other Mochokidae species in Malebo Pool. The study thus provided relevant information regarding the feeding ecology of suckermouth catfishes intrinsically associated with the Congo River, one of the most threatened and biodiverse ecosystems of the Congo basinL'écologie alimentaire du poisson-chat Euchilichthys guentheri (Schilthuis, 1891) du Pool Malebo (fleuve Congo, Kinshasa, RDC) a été étudiée entre janvier 2008 et octobre 2010. Les contenus stomacaux de 243 individus ont été analysés et le régime alimentaire a été caractérisé par le calcul d'un indice alimentaire combinant les pourcentages d'occurrence, numérique et volumétrique, des proies identifiées dans ces contenus stomacaux. Cet examen a révélé que l'espèce a un régime herbivore principalement composé de périphyton (périphytophage). La présente étude n'a pas trouvé de différences statistiquement significatives du régime alimentaire en fonction de la taille des spécimens, du site d'échantillonnage et de la saison hydrologique. Les stratégies alimentaires développées par cette espèce favorisent sa coexistence avec les autres espèces de Mochokidés dans le Pool Malebo. Cette étude fournit ainsi d'utiles informations concernant l'écologie alimentaire des poissons-chats ayant la bouche en ventouse intrinsèquement liés au fleuve Congo, l'un des écosystèmes les plus menacés et les plus diversifiés du bassin du Congo

Feeding ecology of the African suckermouth catfish Euchilichthys guentheri (Mochokidae, Siluriformes) of Malebo Pool, Congo River (Democratic Republic of Congo)

The feeding ecology of Euchilichthys guentheri (Schilthuis, 1891) of Malebo Pool (Congo River, Kinshasa, DRC) was studied between January 2008 and October 2010. The stomach contents of 243 individuals were analysed and a diet was characterized by a feeding index computed by combining the occurrences, the numerical and volume percentages of the items identified in the stomach contents. The study showed that this species has an herbivorous diet mainly composed of periphyton. The study did not find any statistical differences in the diet related to the size of the specimens, the site and the hydrological season. The dietary strategies developed by this species likely contribute to its coexistence with the other Mochokidae species in Malebo Pool. The study thus provided relevant information regarding the feeding ecology of suckermouth catfishes intrinsically associated with the Congo River, one of the most threatened and biodiverse ecosystems of the Congo basin.L’écologie alimentaire du poisson-chat Euchilichthys guentheri (Schilthuis, 1891) du Pool Malebo (fleuve Congo, Kinshasa, RDC) a été étudiée entre janvier 2008 et octobre 2010. Les contenus stomacaux de 243 individus ont été analysés et le régime alimentaire a été caractérisé par le calcul d’un indice alimentaire combinant les pourcentages d’occurrence, numérique et volumétrique, des proies identifiées dans ces contenus stomacaux. Cet examen a révélé que l’espèce a un régime herbivore principalement composé de périphyton (périphytophage). La présente étude n’a pas trouvé de différences statistiquement significatives du régime alimentaire en fonction de la taille des spécimens, du site d’échantillonnage et de la saison hydrologique. Les stratégies alimentaires développées par cette espèce favorisent sa coexistence avec les autres espèces de Mochokidés dans le Pool Malebo. Cette étude fournit ainsi d’utiles informations concernant l’écologie alimentaire des poissons-chats ayant la bouche en ventouse intrinsèquement liés au fleuve Congo, l’un des écosystèmes les plus menacés et les plus diversifiés du bassin du Congo.Tembeni Makiadi John, Mbomba Nseu Bekeli, Micha Jean-Claude, Vandewalle Pierre. Feeding ecology of the African suckermouth catfish Euchilichthys guentheri (Mochokidae, Siluriformes) of Malebo Pool, Congo River (Democratic Republic of Congo). In: Revue d'Écologie (La Terre et La Vie), tome 68, n°3-4, 2013. pp. 291-304

Feeding ecology of the catfish Euchilichthys guentheri (Mochokidae, Siluriformes) of Pool Malebo, Congo River (Democratic Republic of Congo

peer reviewedSummary.— The feeding ecology of Euchilichthys guentheri (Schilthuis, 1891) of Malebo Pool (Congo River, Kinshasa, DRC) was studied between January 2008 and October 2010. The stomach contents of 243 individuals were analysed and a diet was characterized by a feeding index computed by combining the occurrences, the numerical and volume percentages of the items identified in the stomach contents. The study showed that this species has an herbivorous diet mainly composed of periphyton. The study did not find any statistical differences in the diet related to the size of the specimens, the site and the hydrological season. The dietary strategies developed by this species likely contribute to its coexistence with the other Mochokidae species in Malebo Pool. The study thus provided relevant information regarding the feeding ecology of suckermouth catfishes intrinsically associated with the Congo River, one of the most threatened and biodiverse ecosystems of the Congo basin

Feeding ecology of the african suckermouth catfish Euchilichthys Guentheri (Mochokidae, siluriformes) of Malebo Pool, Congo River (Democratic republic of congo)gy of the african suckermouth catfish Euchilichthys Guentheri (Mochokidae, siluriformes) of Malebo Pool, Congo River (Democratic republic of congo)

peer reviewedThe feeding ecology of Euchilichlhys guentheri (Schilthuis, 1891) of Malcbo Pool (Congo River, Kinshasa, DRC) was studied between January 2008 and October 2010. The stomach contents of 243 individuals were analysed and a diet was characterized by a feeding index computed by combining the occurrences, the numerical and volume percentages of the items identified in the stomach contents. The study showed that this species has an herbivorous diet mainly composed of periphyton. The study did not find any statistical differences in the diet related to the size of the specimens, the site and the hydrological season. The dietary strategics developed by this species likely contribute to its coexistence with the other Mochokidae species in Malcbo Pool. The study thus provided relevant information regarding the feeding ecology of suckermouth catfishes intrinsically associated with the Congo River, one of the most threatened and biodiverse ecosystems of the Congo basin

Feeding ecology of the african suckermouth catfish Euchilichthys Guentheri (Mochokidae, siluriformes) of Malebo Pool, Congo River (Democratic republic of congo)

peer reviewedThe feeding ecology of Euchilichlhys guentheri (Schilthuis, 1891) of Malcbo Pool (Congo River, Kinshasa, DRC) was studied between January 2008 and October 2010. The stomach contents of 243 individuals were analysed and a diet was characterized by a feeding index computed by combining the occurrences, the numerical and volume percentages of the items identified in the stomach contents. The study showed that this species has an herbivorous diet mainly composed of periphyton. The study did not find any statistical differences in the diet related to the size of the specimens, the site and the hydrological season. The dietary strategics developed by this species likely contribute to its coexistence with the other Mochokidae species in Malcbo Pool. The study thus provided relevant information regarding the feeding ecology of suckermouth catfishes intrinsically associated with the Congo River, one of the most threatened and biodiverse ecosystems of the Congo basin

Utilisation des plantes médicinales dans le traitement traditionnel des morsures de serpents par les habitants des villages environnants de la station de l’INERA Kiyaka (Province du Kwilu)

La présente enquête ethnobotanique a pour objectif d’inventorier et d’identifier les plantes médicinales utilisées dans le traitement traditionnel des morsures de serpents par les habitants des villages environnants de la station de l’INERA Kiyaka durant la période du 04 Mars au 04 Mai 2024. Au total, 66 plantes appartenant à 36 familles botaniques ont été inventoriées dont la plus représentée est les Fabaceae. Ces enquêtes ont permis d’obtenir 92 recettes dont 53 contre le traitement, 13 pour la prévention, 26 à la fois pour le traitement et la prévention des morsures de serpents. Les feuilles, la décoction et la trituration, la scarification et la friction, les médicaments employés jusqu’à la guérison ont constitué respectivement l’organe, les modes de préparation des recettes et d’administration des remèdes ainsi que la durée des traitements auxquels les habitants de cette région d’étude ont mis beaucoup d’accents. Il est donc souhaitable que les études bibliographiques soient réalisées sur ces plantes en vue de recueillir les données scientifiques pouvant orienter les recherches pharmaco-biologiques et phytochimiques futures susceptibles de conduire à la domestication des matières premières pour la fabrication des médicaments traditionnels antivenimeux et antimorsures améliorés. Aussi, la création d’un jardin botanique de plantes médicinales pourra contribuer à la sauvegarde des espèces bioactives, à la diffusion et à l’échange des connaissances et des expériences médico-pharmaceutiques et socio-culturelles

Breeding strategy of Nannothrissa stewarti Poll & Roberts 1976 (Clupeidae) in lake Mai-Ndombe, Democratic Republic of Congo

Background. Clupeidae, Nannothrissa stewarti (Poll & Roberts 1976) endemic to Lake Mai-Ndombe is one of most heavily fished fish groups using practices and nets not allowed by the country's legislation. Objective of this study was to determine some aspects of reproductive biology of N. stewarti in Lake Mai-Ndombe.Materials and methods. Fish were sampled monthly from November 2020 to October 2021 breeding parameters were determined : Gonado-somatic index (GSI), Size at first sexual maturity, Absolute fecundity and the relationship between total weight (WT) and total length.Results. Results obtained showed that the sex ratio was in favor of females (1 : 0.8). Estimated absolute fecundity was between 227 and 4080 oocytes for females of total length between 23 and 35 mm with an average of 923 ± 664 g oocytes and a relative fecundity varying between 25115 and 155457 oocytes kg-1. Average oocyte diameter was 0.20 ± 0.14 mm. Distribution of oocyte diameters observed in the population as well as monthly variations of the Somatic Gonado Index (SGI) indicate that the species has two main clutches during the year. LT50 size at first sexual maturity is 27.6 mm for males and 25.5 mm for females.Conclusion. N. stewarti from Lake Mai-Ndombe has multiple reproduction throughout year with however two maximum peaks at the beginning of peak rainfall (February-March and September-October)

Breeding Strategy of Nannothrissa stewarti POLL and ROBERTS 1976 (Clupeidae) in Lake Mai-Ndombe, Democratic Republic of Congo

The clupeid, Nannothrissa stewarti (Poll and Roberts 1976), endemic to Lake Mai-Ndombe, is one of the most heavily fished fish species using practices and nets not allowed by the country's legislation. The objective of this study was to determine some aspects of the reproductive biology of N. stewarti in Lake Mai-Ndombe. Fish were monthly sampled from November 2020 to October 2021. Breeding parameters were determined: gonado-somatic index (GSI), size at first sexual maturity, absolute fecundity and the relationship between total weight (TW) and total length (TL). Results obtained showed that the sex ratio was in favor of females (1: 0.8). Estimated absolute fecundity was between 227 and 4080 oocytes for females of total length between 23 and 35mm, with an average of 923 ± 664g oocytes and a relative fecundity varying between 25120 and 155460 oocytes kg-1. The average oocyte diameter was 0.20 ± 0.14mm. Distribution of oocyte diameters observed in the population as well as monthly variations of the Somatic Gonado Index (SGI) indicates that the species has two main clutches during the year. LT50 size at first sexual maturity is 27.6mm for males and 25.5mm for females. N. stewarti from Lake Mai-Ndombe has multiple reproductions throughout the year, with two maximum peaks at the beginning of the peak rainfall (February-March and September-October).</p

Phytoplankton dynamics in the Congo River

We report a dataset of phytoplankton in the Congo River, acquired along a 1700-km stretch in the mainstem during high water (HW, December 2013) and falling water (FW, June 2014). Samples for phytoplankton analysis were collected in the main river, in tributaries and one lake, and various relevant environmental variables were measured. Phytoplankton biomass and composition were determined by high-performance liquid chromatography analysis of chlorophyll a (Chl a) and marker pigments and by microscopy. Primary production measurements were made using the 13C incubation technique. In addition, data are also reported from a 19-month regular sampling (bi-monthly) at a fixed station in the mainstem of the upper Congo (at the city of Kisangani). * Chl a concentrations differed between the two periods studied: in the mainstem, they varied between 0.07 and 1.77 μg L−1 in HW conditions and between 1.13 and 7.68 μg L−1 in FW conditions. The relative contribution to phytoplankton biomass from tributaries (mostly black waters) and from a few permanent lakes was low, and the main confluences resulted in phytoplankton dilution. Based on marker pigment concentration, green algae (both chlorophytes and streptophytes) dominated in the mainstem in HW, whereas diatoms dominated in FW; cryptophytes and cyanobacteria were more abundant but still relatively low in the FW period, both in the tributaries and in the main channel.  15) varied between 64.3 and 434.1 mg C m−2 day−1 in FW conditions and between 51.5 and 247.6 mg C m−2 day−1 in HW. Phytoplankton biomass in the Congo River mainstem was likely constrained by hydrological factors (accumulation due to increased retention time during FW, dilution by increased discharge during HW), even though increased nutrient availability in the FW period might have also stimulated phytoplankton production. * In contrast to other tropical river systems where connectivity with the floodplain and the presence of natural lakes and man-made reservoirs play a prominent role in the recruitment of phytoplankton to the main river, our results show that phytoplankton growth in the Congo River can take place in the main channel, with hydrological processes allowing maintenance of phytoplankton biomass even during HW.AFRIVA