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Multi-mammate rats (Muridae, Murinae, Mastomys spp.) are Sub-Saharan pest rodents, the systematics of which has long remained confused due to poor morphologic differentiation. Cytotaxonomy and DNA sequencing have provided excellent diagnostic markers for species identification, thus improving the assessment of taxonomic diversity within the genus. In West and Central Africa, three species have been unambiguously identified and are now well documented: Mastomys erythroleucus, Mastomys natalensis and Mastomys huberti. However, recent studies suggest the existence of two other taxa on the basis of morphology, DNA sequencing (Mastomys verheyeni, from Nigeria and Northern Cameroon) or karyotypes (Mastomys cf. kollmannspergeri, from Northern Niger and Chad). In order to clarify the systematic status of the latter taxa, we collected all the available cytotaxonomic as well as cytochrome b sequencing data to which were added results obtained from recently trapped specimens in Northern Cameroon. Our combined molecular and cytogenetic analyses unambiguously confirm the presence of another Mastomys species inhabiting various habitats in Niger, Nigeria, Cameroon, Chad and Sudan. This taxon is clearly differentiated from M. erythroleucus, M. huberti and M. natalensis. Furthermore, the inclusion in our analysis of two M. verheyeni paratypes as well as individuals trapped in close vicinity to the type locality of M. kollmannspergeri supports the assignation of all specimens to M. kollmanspergeri, thus making M. verheyeni its junior synonym. Our study once again highlights the reliability of DNA- and karyotype-based methods to accurately assess specific diversity in African rodents, particularly in the Mastomys genus, which shelters several species of agricultural and epidemiological importance.

The aim of the study was to evaluate the incidence and the etiology of Mallory-Weiss syndrome in children. The study population comprised 2720 children aged 5 months to 18 years who had undergone upper gastrointestinal endoscopy. Mallory-Weiss syndrome was diagnosed in eight (0.3%) of the examined children. Endoscopic examination in five of them revealed linear mucosal tears, mostly above and in one case also below the gastroesophageal junction. In three children a linear scar in the lower portion of the esophagus was seen. No signs of active bleeding were revealed in any of the cases. In four children, Mallory-Weiss syndrome was accompanied by gastritis and duodenitis; two of these children had Helicobacter pylori infection. The concomitant diseases were H. pylori-positive duodenal ulcer (1), bronchial asthma and gastroesophageal reflux disease (1), carbon monoxide poisoning (1). In one case Mallory-Weiss syndrome was diagnosed in early pregnancy. Mallory-Weiss syndrome should be considered, along with others, as a cause of acute upper gastrointestinal bleeding in children. There is a great variety of etiologic factors in Mallory-Weiss syndrome in children.

Nous avons analysé des pelotes de réjection de la chouette effraie (#Tyto alba$), récoltées en divers sites et à différentes époques dans le Parc National des Oiseaux du Djoudj (Sénégal). Les rongeurs représentent près de 88% des proies, les musaraignes 7,5% et les oiseaux moins de 5%. Au moins neuf espèces de rongeurs appartenant à trois sous-familles différentes (Murinae, Gerbillinae et Dipodinae) et quatre espèces de musaraignes appartenant toutes au genre #Crocidura$, ont pu être identifiées. Parmi les rongeurs on note la prédominance des #Mastomys$ spp. (71,5%), suivis de #Arvicanthis niloticus$ (20%), les autres espèces ne comptant que pour 0,2 à 3% du régime alimentaire de l'effraie. Les deux espèces de #Mastomys$, #M. erythroleucus$ et #M. huberti$, présentes dans la zone ne sont pas différenciables par la morphologie crânienne. #A. niloticus$ est probablement sous-représenté par rapport à son abondance réelle en raison de son rythme d'activité plutôt diurne. Un peu plus de la moitié des musaraignes trouvées dans les pelotes appartiennent à l'espèce #Crocidura nanilla$ et un tiers à l'espèce #Crocidura lusitania$. La diversité des proies reflète bien la composition du peuplement micromammalien et est révélateur de la mosaïque d'habitats que constitue le delta du Sénégal. (Résumé d'auteur)

Following the reemergence of Rift Valley fever (RVF) virus in southeastern Mauritania in 1998, an entomological survey was undertaken in the boundary area in Senegal to assess the extent of the virus circulation. During this study, RVF virus (36 strains) was isolated for the first time from #Culex poicilipes$ in nature. The possible role of #Cx. poicilipes$ as an RVF vector is discussed regarding its biology and ecology. (Résumé d'auteur)

Maltodextrin is a mixture of saccharides with a molecular weight between polysaccharides and oligosaccharides with DE lower than 20. Maltodextrin is more soluble in water than native starches, also is cheaper in comparison with other major edible hydrocolloids. Maltodextrin is obtained by moderate enzymatic or acidic hydrolysis of starch. The hydrolysis of starch, catalyzed by amylases, is the most important commercial enzyme process. The hydrolyzed products are widely applied in food, paper and textile industries. Because of the increasing demand for these enzymes in various industries, there is enormous interest in developing enzymes with better properties, such as raw starch-degrading amylases suitable for industrial applications and their cost-effective production techniques. Sorghum (Sorghum bicolor) is a widely grown crop in Africa. Obtaining enzymes from sorghum requires a transformation. The objective of this study was application of sorghum amylase for maltodextrin. Sorghum seeds were supplied by the ISRA (Bambey, Senegal). Seeds were germinated in the laboratory at 30°C for 72 h and the sorghum malt was dried at 40°C for 48 h. Corn starch (from Roquette, France) hydrolysis was assayed in a bioreactor of 2 l at a temperature of 65°C gently stirred. Raw starch was slurried in water (30% w/v) and sorghum malt was introduced, chloride calcium was added, pH was adjusted to 6. Maltodextrin was characterized in term of the dextrose equivalent (DE) during the hydrolysis. The yield of hydrolysis was evaluated by soluble solids (° BRIX) at different hydrolysis time. The glucose concentration released was measured by DNS method (Miller method).

Ce rapport énumère une trentaine d'espèces de mammifères observées sur la station ORSTOM de M'Bour. Six ordres de mammifères sont représentés sur la station. Un seul manque par rapport au peuplement de la région; celui des Artiodactyles. La proximité de la ville et la petite taille de la station s'opposent au maintien d'une population naturelle de ces grands mammifères

BackgroundSchistosomiasis and food-borne trematodiases are not only of major public health concern, but can also have profound implications for livestock production and wildlife conservation. The zoonotic, multi-host nature of many digenean trematodes is a significant challenge for disease control programmes in endemic areas. However, our understanding of the epidemiological role that animal reservoirs, particularly wild hosts, may play in the transmission of zoonotic trematodiases suffers a dearth of information, with few, if any, standardised, reliable diagnostic tests available. We combined qualitative and quantitative data derived from post-mortem examinations, coprological analyses using the Mini-FLOTAC technique, and molecular tools to assess parasite community composition and the validity of non-invasive methods to detect trematode infections in 89 wild Hubert’s multimammate mice (Mastomys huberti) from northern Senegal.ResultsParasites isolated at post-mortem examination were identified asPlagiorchissp.,Anchitremasp.,Echinostoma caproni,Schistosoma mansoni, and a hybrid betweenSchistosoma haematobiumandSchistosoma bovis. The reports ofE. caproniandAnchitremasp. represent the first molecularly confirmed identifications for these trematodes in definitive hosts of sub-Saharan Africa. Comparison of prevalence estimates derived from parasitological analysis at post-mortem examination and Mini-FLOTAC analysis showed non-significant differences indicating comparable results between the two techniques (P = 1.00 forS. mansoni;P = 0.85 forE. caproni;P = 0.83 forPlagiorchissp.). A Bayesian model, applied to estimate the sensitivities of the two tests for the diagnosis ofSchistosomainfections, indicated similar median posterior probabilities of 83.1% for Mini-FLOTAC technique and 82.9% for post-mortem examination (95% Bayesian credible intervals of 64.0–94.6% and 63.7–94.7%, respectively).ConclusionsOur results showed that the Mini-FLOTAC could be applied as an alternative diagnostic technique for the detection of the zoonoticS. mansoniand other trematodes in rodent reservoirs. The implementation of non-invasive diagnostics in wildlife would offer numerous advantages over lethal sampling methodologies, with potential impact on control strategies of zoonotic helminthiases in endemic areas of sub-Saharan Africa and on fostering a framework of animal use reduction in scientific practice.