Maman Laminou Ibrahim

MVD. MSc. PhD.
Head of Department of Parasitology
Centre for Medical Research an... · Parasitologie

Publications

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    ABSTRACT: Chloroquine (CQ) resistance is widespread in Africa, but few data are available for Niger. Pfcrt haplotypes (aa 56–118) and ex vivo responses to CQ and amodiaquine were characterized for 26 isolates collected in South Niger from children under 15 years of age suffering from uncomplicated falciparum malaria, six years after the introduction of artemisinin-based combinations and the withdrawal of CQ. The wild-type Pfcrt haplotype CVMNK was found in 22 of the 26 isolates, with CVIET sequences observed in only three of the samples. We also describe for the first time a new CVINT haplotype. The ex vivo responses were better for CVMNK than for CVIET parasites. Pfcrt sequence data were compared with those obtained for 26 additional parasitized blood samples collected in Gabon, from an area of CQ resistance used as a control. Our findings suggest that there has been a significant decline in CQ-resistant genotypes since the previous estimates for Niger were obtained. No such decline in molecular resistance to CQ was observed in the subset of samples collected in similar conditions from Gabon.These results have important implications for public health and support the policy implemented in Niger since 2005, which aims to increase the efficacy and availability of antimalarial drugs whilst controlling the spread of resistance.
    Malaria Research and Treatment. 01/2014; 2014:7.
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    ABSTRACT: Few data are available about malaria epidemiological situation in Niger. However, implementation of new strategies such as vaccination or seasonal treatment of a target population requires the knowledge of baseline epidemiological features of malaria. A population-based study was conducted to provide better characterization of malaria seasonal variations and population groups the most at risk in this particular area. From July 2007 to December 2009, presumptive cases of malaria among a study population living in a typical Sahelian village of Niger were recorded, and confirmed by microscopic examination. In parallel, asymptomatic carriers were actively detected at the end of each dry season in 2007, 2008 and 2009. Among the 965 presumptive malaria cases recorded, 29% were confirmed by microscopic examination. The incidence of malaria was found to decrease significantly with age (p < 0.01). The mean annual incidence was 0.254. The results show that the risk of malaria was higher in children under ten years (p < 0.0001). The number of malaria episodes generally followed the temporal pattern of changes in precipitation levels, with a peak of transmission in August and September. One-thousand and ninety subjects were submitted to an active detection of asymptomatic carriage of whom 16% tested positive; asymptomatic carriage decreased with increasing age. A higher prevalence of gametocyte carriage among asymptomatic population was recorded in children aged two to ten years, though it did not reach significance. In Southern Niger, malaria transmission mostly occurs from July to October. Children aged two to ten years are the most at risk of malaria, and may also represent the main reservoir for gametocytes. Strategies such as intermittent preventive treatment in children (IPTc) could be of interest in this area, where malaria transmission is highly seasonal. Based on these preliminary data, a pilot study could be implemented in Zindarou using IPTc targeting children aged two to ten years, during the three months of malaria transmission, together with an accurate monitoring of drug resistance.
    Malaria Journal 10/2013; 12(1):379. · 3.49 Impact Factor
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    ABSTRACT: Individuals continuously exposed to malaria gradually acquire immunity that protects from severe disease and high levels of parasitization. Acquired immunity has been incorporated into numerous models of malaria transmission of varying levels of complexity (e.g. Bull World Health Organ 50:347, 1974; Am J Trop Med Hyg 75:19, 2006; Math Biosci 90:385--396, 1988). Most such models require prescribing inputs of mosquito biting rates or other entomological or epidemiological information. Here, we present a model with a novel structure that uses environmental controls of mosquito population dynamics to simulate the mosquito biting rates, malaria prevalence as well as variability in protective immunity of the population. A simple model of acquired immunity to malaria is presented and tested within the framework of the Hydrology, Entomology and Malaria Transmission Simulator (HYDREMATS), a coupled hydrology and agent-based entomology model. The combined model uses environmental data including rainfall, temperature, and topography to simulate malaria prevalence and level of acquired immunity in the human population. The model is used to demonstrate the effect of acquired immunity on malaria prevalence in two Niger villages that are hydrologically and entomologically very different. Simulations are conducted for the year 2006 and compared to malaria prevalence observations collected from the two villages. Blood smear samples from children show no clear difference in malaria prevalence between the two villages despite pronounced differences in observed mosquito abundance. The similarity in prevalence is attributed to the moderating effect of acquired immunity, which depends on prior exposure to the parasite through infectious bites - and thus the hydrologically determined mosquito abundance. Modelling the level of acquired immunity can affect village vulnerability to climatic anomalies. The model presented has a novel structure constituting a mechanistic link between spatial and temporal environmental variability and village-scale malaria transmission. Incorporating acquired immunity into the model has allowed simulation of prevalence in the two villages, and isolation of the effects of acquired immunity in dampening the difference in prevalence between the two villages. Without these effects, the difference in prevalence between the two villages would have been significantly larger in response to the large differences in mosquito populations and the associated biting rates.
    Parasites & Vectors 08/2013; 6(1):226. · 3.25 Impact Factor
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    ABSTRACT: Le Niger a adopté une nouvelle politique thérapeutique du paludisme en 2005. Elle recommande l’artémether luméfantrine (AL) en traitement du paludisme simple, la sulfadoxine pyriméthamine (SP) en traitement préventif intermittent et le retrait de la chloroquine (CQ). Pourtant, la chloroquine continue d’être prescrite et la sulfadoxine pyriméthamine est fréquemment utilisée pour traiter les enfants. Une étude comparative, randomisée, à trois bras aveugles de l’efficacité de l’artémether luméfantrine, la sulfadoxine pyriméthamine et la chloroquine est réalisée à Gaya. L’objectif de l’étude est d’évaluer l’efficacité des trois médicaments. Cette étude a porté sur 208 enfants. Le protocole OMS/2003 est utilisé. Les familles alléliques RO33 et MAD20 du marqueur msp1 puis 3D7 et FC27 du marqueur msp2 sont utilisées pour distinguer réinfestations et recrudescences. 93.6% des patients traités à l’artémether luméfantrine ont une réponse clinique et parasitologique adéquate contre 82.8% des patients traités à la sulfadoxine pyriméthamine et 72% des patients traités à la chloroquine. La différence d’efficacité est statistiquement significative (p=0.04). Au vue de ces résultats, il serait judicieux de retirer la chloroquine. La sulfadoxine pyriméthamine doit être réservée exclusivement aux femmes enceintes. L’artémether luméfantrine doit être prescrit en traitement de première intention.
    Annales de l'Université Abdou Moumouni,. 01/2013;
  • Maman Laminou Ibrahim
    Malaria Journal 01/2013; · 3.49 Impact Factor
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    ABSTRACT: The health authorities of Niger have implemented several malaria prevention and control programmes in recent years. These interventions broadly follow WHO guidelines and international recommendations and are based on interventions that have proved successful in other parts of Africa. Most performance indicators are satisfactory but, paradoxically, despite the mobilization of considerable human and financial resources, the malaria-fighting programme in Niger seems to have stalled, as it has not yet yielded the expected significant decrease in malaria burden. Indeed, the number of malaria cases reported by the National Health Information System has actually increased by a factor of five over the last decade, from about 600,000 in 2000 to about 3,000,000 in 2010. One of the weaknesses of the national reporting system is that the recording of malaria cases is still based on a presumptive diagnosis approach, which overestimates malaria incidence. An extensive nationwide survey was carried out to determine by microscopy and RDT testing, the proportion of febrile patients consulting at health facilities for suspected malaria actually suffering from the disease, as a means of assessing the magnitude of this problem and obtaining a better estimate of malaria morbidity in Niger. In total, 12,576 febrile patients were included in this study; 57% of the slides analysed were positive for the malaria parasite during the rainy season, when transmission rates are high, and 9% of the slides analysed were positive during the dry season, when transmission rates are lower. The replacement of microscopy methods by rapid diagnostic tests resulted in an even lower rate of confirmation, with only 42% of cases testing positive during the rainy season, and 4% during the dry season. Fever alone has a low predictive value, with a low specificity and sensitivity. These data highlight the absolute necessity of confirming all reported malaria cases by biological diagnosis methods, to increase the accuracy of the malaria indicators used in monitoring and evaluation processes and to improve patient care in the more remote areas of Niger. This country extends over a large range of latitudes, resulting in the existence of three major bioclimatic zones determining vector distribution and endemicity. This survey showed that the number of cases of presumed malaria reported in health centres in Niger is largely overestimated. The results highlight inadequacies in the description of the malaria situation and disease risk in Niger, due to the over-diagnosis of malaria in patients with simple febrile illness. They point out the necessity of confirming all cases of suspected malaria by biological diagnosis methods and the need to take geographic constraints into account more effectively, to improve malaria control and to adapt the choice of diagnostic method to the epidemiological situation in the area concerned. Case confirmation will thus also require a change in behaviour, through the training of healthcare staff, the introduction of quality control, greater supervision of the integrated health centres, the implementation of good clinical practice and a general optimization of the use of available diagnostic methods.
    Malaria Journal 03/2012; 11:89. · 3.49 Impact Factor
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    ABSTRACT: Background: Malaria, with its width, its gravity and its economic and social consequences remains a major public health problem in tropical countries like Niger. These consequences come to be added the simultaneous or cross résistance of P.falciparum to currents drugs. The National Malaria Programme of Niger adopted artemether-lumefantrine (COARTEM®) in treatment of uncomplicated malaria in 2005. We evaluated the efficacy and safety of artémether-luméfantrine in the treatment of children less than 5 years at Gaya, Tessaoua and Agades, three sentinels’ sites of Niger. Objectives: The main objective of the study is to evaluate the efficacy and the safety of COARTEM® in the treatment of uncomplicated P.falciparum malaria in Niger. Methodology: It is a multicentric, prospective, descriptive and open study with only one arm to evaluate the efficacy and safety of artemether-lumefantrine in children less than 5 years suffering from uncomplicated malaria in Niger. OMS/2003 protocol was used. Results: 389 children were consulted and 199 children were followed for 28 days. 81 children are from Gaya, 70 from Tessaoua and 48 from Agades. After PCR, the clinical and parasitological adequate response (CPAR) of children less than 5 years is 92%. The CPAR is 96.3% at Tessaoua, 94,1% at Agades and 89.6% at Gaya. The difference of response between the three sentinels sites is not significant (p>0 05). Before PCR, the clinical and parasitological adequate response was 88.8%. The COARTEM® is well tolerated. No undesirable effect was observed during the study. Conclusion: COARTEM® is an effective drug, which reduces significantly parasitic and clinical symptoms of malaria. It can be prescribed in treatment of uncomplicated malaria as public health ministry of Niger recommends. COARTEM® is also safety and well tolerated by the patients.
    J. Rech. Sci. Univ. Lomé (Togo). 01/2012; 14(1-14(1) :):79-84.
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    ABSTRACT: ORAL PRESENTATION Open Access Controlling malaria in Niger with bednets: how to take the Big Picture Duchemin Jean-Bernard1,2*, Czeher Cyrille1, Labbo Rabiou1, Ibrahim M Lamine1, Hoyer Stefan3, Jeanne Isabelle1 From Parasite to Prevention: Advances in the understanding of malaria Edinburgh, UK. 20-22 October 2010 Background In December 2005 free long lasting insecticidal nets were distributed to mothers of children under five in a nation-wide scheme in Niger. More than 2 million bed nets were distributed, increasing the ownership of insecticide treated bed nets more than tenfold. Materials and methods Our team was in charge of the malaria survey. The malaria cases were reported through a network of 44 sites across the country. Malaria transmission was surveyed in 12 villages in the Sahel, as it was deemed the most variable zone. Results and discussion During the first year of follow-up, vector dynamics showed an overall decrease in malaria transmission, but this was highly variable from village to village. Indeed, the second year of survey showed a return to transmission levels close to the pre-intervention period. A study of microsatellite markers showed no modification of the genetic structure in the two malaria vectors An. gambiae and An. arabiensis. However, a clear increase of the resistant allele of the kdr gene - resistence to the pyrethroid insecticide used in the bed nets - was observed. This clearly demonstrated that the main target vectors were reached. As measured by ovarian tracheoles observation, the parity rate of vectors was not significantly decreased. However, the index sporozoite decreased in the first year and remained low in the second year. Indeed, the parasite prevalence and the gametocyte carriage were shown decreasing in the children under five. This continued in 2007 as the National Malaria Control Program provided free artemisinin-based combination therapies as first line treatment for malaria in children under five. The national survey network showed a decrease in malaria cases, as confirmed in our sentinelle sites. However the biological confirmation of cases by HRP2 plasmodial antigen research has increased during the two years of follow-up. This could be explained by the more accurate diagnosis by peripheral health personal with the help of rapid diagnostic tests. Conclusion Our survey system allowed the report of the malaria evolution during that important period of control reinforcement in Niger. The causative impact was difficult to confirm because several lines of malaria control have been successively implemented. Moreover, the high climatic variability in this zone needs to be taken in account in the analysis. Despite these difficulties our data reinforce the importance of malaria monitoring through multidisciplinary studies to the benefit of control operations. Acknowledgements Funded by the Global Fund and the World Health Organization. Author details 1CERMES, BP 10887, Niamey, Niger. 2Genetics and Genomics Insect Vectors Unit, Institut Pasteur, 25-28 rue du Dr Roux, 75724 Paris Cedex 15, France. 3Global Malaria Programme, World Health Organization, 20 Avenue Appia, CH 1211 Geneva 27, Switzerland. Published: 20 October 2010 doi:10.1186/1475-2875-9-S2-O12 Cite this article as: Jean-Bernard et al.: Controlling malaria in Niger with bednets: how to take the Big Picture. Malaria Journal 2010 9(Suppl 2):O12. 1CERMES, BP 10887, Niamey, Niger Full list of author information is available at the end of the article Jean-Bernard et al. Malaria Journal 2010, 9(Suppl 2):O12 http://www.malariajournal.com/content/9/S2/O12 © 2010 Jean-Bernard et al; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
    Malaria Journal 01/2010; 9(2-9(Suppl 2):O12). · 3.49 Impact Factor
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    ABSTRACT: Plasmodium falciparum resistance to drugs remains a major public health issue in Niger. The therapeutic failure index for chloroquine and sulphadoxine-pyrimethamine are, respectively 20% and 21.9%. In December 2005, the National Malaria Control Programme promoted the use of artemisinin combination therapy (ACT) as first-line treatment of the uncomplicated malaria cases. Recently, studies have shown a relationship between the SERCA PfATPase6 gene and artemisinin efficacy, and pointed it out as a potential molecular marker for resistance. The goal of this work was to describe the baseline polymorphism of PfATPase6 gene in Niger, at a time when the national implementation of the ACT policy had just begun. The DNA polymorphism of the PfATPase6 gene of 87 P. falciparum samples from Niger was analysed by sequencing. The links between the mutation occurrence and environment and human host factors were tested by bivariate analysis. The P. falciparum PfATPase6 gene presented polymorphisms at codons 537, 561, 569, 630, 639, 716 levels. All the mutations found were rare, except the PfATPaseN569K found in 17.2% of samples. No associated factor has been observed. The P. falciparum PfATPase gene is polymorphic at the 569 codon. As ACT is getting more and more used, the PfATPase6 gene polymorphism needs to be monitored in association with phenotypic - in vivo and/or in vitro - drug efficacy tests.
    Malaria Journal 03/2009; 8:28. · 3.49 Impact Factor
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    ABSTRACT: Over the last years, significant progress has been made in the comprehension of the molecular mechanism of malaria resistance to drugs. Together with in vivo tests, the molecular monitoring is now part of the survey strategy of the Plasmodium sensitivity. Currently, DNA-microarray analysis allows the simultaneous study of many single nucleotide polymorphisms (SNP) of Plasmodium isolates. In December 2005, the International Federation of the Red Cross distributed two million three hundred thousand long-lasting insecticide nets to pregnant women and mothers of under five years children in the whole Niger. Then, Niger adopted artemisinin-based combination therapy as first-line treatment. Thirty four SNPs of pfcrt, pfdhfr, pfdhps, pfmdr and pfATPase were analysed by DNA-microarray and PCR/RFLP in two villages - Zindarou and Banizoumbou - with different durations of malaria transmission. The main objective of the study was to measure the dynamics of Plasmodium falciparum resistant strains and associated factors. This study shows a global and clear increase of the drug-resistance associated molecular markers frequencies during a relatively short-time period of four years. Markers associated with resistance to chloroquine and sulphonamids were more frequently found in the short transmission zone than in the long transmission one. The pfcrt76T mutation is significantly more present at Banizoumbou than Zindarou (38.3% vs 25.2%, p = 0.013). This work allowed the screening of several field strains for five SNPs of PfATPase6 gene. The pfATPase6S769N, candidate mutation of resistance to artemisinin was not found. However the pfATPsaeA623E mutation was found in 4.7% of samples. A significant increase of several SNPs frequencies was highlighted over a four-year period. The polymorphism of five PfATPase6 gene SNPs was described. The global, large and fast increase of the molecular resistance is discussed in the context of current changes of health policy and malaria control in Niger.
    Malaria Journal 03/2009; 8:32. · 3.49 Impact Factor
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    IBRAHIM M.laminou
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    ABSTRACT: La résistance de P.falciparum à la chloroquine est associée à une forte augmentation de la mortalité en Afrique tropicale où le risque de décès palustre chez les enfants de 0 à 9 ans a été multiplié par 2 à 5 dans la plupart des contextes épidémiologiques. Au Niger, les données sur la chimiosensibilité aux antipaludiques sont fragmentaires et les récentes études in vivo effectuées à Niamey font état d’un niveau préoccupant de 20% d’échec clinique et parasitologique chez les enfants de 1-5 ans. A l’instar de certains pays d’Afrique de l’Est et d’Afrique centrale qui ont remplacé la chloroquine par l’association sulfadoxine-pyriméthamine et plus récemment par les combinaisons thérapeutiques à base d’artémisinine, le ministère de la santé publique du Niger vient d’adopter une combinaison thérapeutique à base d’artémisinine (COARTEM®) pour le traitement de première intention du paludisme simple sans toutefois retirer la chloroquine et l’association sulfadoxine-pyriméthamine en traitement préventif intermittent chez la femme enceinte. En raison de l’adoption des ACT et de la distribution massive de moustiquaires imprégnées, il nous a paru opportun de surveiller la résistance à la chloroquine, la pyriméthamine, les sulfamides et les ACT en utilisant les récentes avancées technologiques de la biologie moléculaire. L’objectif général de ce travail est d’étudier la résistance moléculaire de P.falciparum aux antipaludiques selon le profil clinique des porteurs (accès palustre grave, simple et porteurs asymptomatiques) et selon le faciès de transmission anophélienne (stable vs instable) au Niger. La recherche de mutations ponctuelles (Single Nucleotid Polymorphism ou SNPs) associées à la résistance à la chloroquine (Pfcrt), à la sulfadoxine pyriméthamine (Dhfr et dhps) et à l’artémisinine (pf ATPase) a été effectuée par PCR/RLFP, puces à ADN et par séquençage. La prévalence de la mutation pfcrt76T-corrélée à la chloroquinorésistance- est de 45.4% à l’hôpital National de Niamey. Celle de la mutation pfdhfr108N- corrélée à la pyriméthaminorésistance- est de 61.9%. La mutation dhfr108N est positivement corrélée à l’anémie sévère (p=0.002). En effet, la moyenne de l’hémoglobine tend à baisser significativement de 6.59g/dl à 5.40g/dL en présence de cette mutation (n=84, p=0.023). Les souches sauvages pfcrtK76 par contre sont associées au neuropaludisme et aux symptômes nerveux tels la convulsion et le coma (p=0.043). Le risque de décès par neuropaludisme diminue (p=0.012) en présence de pfcrt76T. La cartographie de la résistance moléculaire a été établie dans la vallée du fleuve Niger où la prévalence de la mutation K76T du gène pfcrt est de 50,8% et celle de la mutation S108N du gène pfdhfr est de 57.7%. L’analyse de 34 SNPs de cinq marqueurs de résistance (pfcrt, pfdhfr, pfdhps, pfmdr et pfATPase) entre deux villages (Banizoumbou et Zindarou) où l’intensité de transmission est différente, révèle que la résistance est plus forte lorsque la transmission est faible. La prévalence de la mutation pfcrtK76T est de 38.3% à Banizoumbou contre 25.2% à Zindarou (p=0.012). La méthode des puces à ADN a révélé une dynamique marquée dans la fréquence des mutations conférant la résistance à plusieurs molécules antipaludiques au cours des 4 ans d’étude. Au moment où la plupart des états Africain ont adoptés les ACT, un screening moléculaire du gène pfATPase est d’une grande importance. Le polymorphisme du gène pfATPase6 a été décrit pour la première fois au Niger où 6 mutations dont 3 nouvelles (537, 561, 716) ont été mises en évidence. La mutation pfATPaseSer769Asn candidate de la résistance à l’artémisinine est absente des souches de Plasmodium falciparum séquencées. Parmi les 6 SNPs du gène pfATPase décrits, la mutation PfATPaseAsn569Lys est la plus fréquente (17.2%). Cette mutation n’est pas neutre. Serait-elle la cible de cette résistance à l’artémisinine ? Des investigations fonctionnelles futures sont indispensables pour élucider son rôle et mettre en place des outils moléculaires de son diagnostic.
    Biologie, Université Cheick Anta Diop, 01/2009, Degree: PhD.
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    ABSTRACT: Plasmodium falciparum resistance to chloroquine first arose in Africa 25 years ago. Nowadays most of African malaria control programmes have switched their first-line treatment of uncomplicated malaria cases towards artemisinin derivatives combination. After WHO guidelines, a survey network for malaria treatment resistance has been set up in the Niger valley around Niamey since December 2004. The association of the Niger national malaria control programme with the CERMES research center allowed collecting of samples from both health centers and hospitals of this region. Blood finger-pricks on filter papers were tested for detection of plasmodial antigen in health center without biological diagnosis capacity. Specimens found positive either in hospital laboratory or by using antigen method were tested by PCR/RFLP to detect K76T mutations on the pfcrt gene and S108N mutation on the pfdhfr gene. This simple procedure allows the screening of a large number of specimens. Moreover, a spatial distribution of mutations and evidence of resistance clusters were searched integrating the data in a geographic information system. The 76T mutation of pfcrt and 108N of pfdhfr were respectively found in 50.8% and 57% of the specimens tested. No statistically significant difference was found according to the level of sanitary formations or the age of the patients. No resistance cluster was identified and the prevalence of mutation seems homogeneous in the zone. By completing the clinical efficacy studies we think that our simple method for collecting and testing blood samples associated with clinical efficacy studies may be useful for building a network of malaria drug resistance in Africa.
    Bulletin de la Société de pathologie exotique 03/2008; 101(1):47-9.
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    ABSTRACT: In the framework of the monitoring and evaluation of the Nigerian schistosomiasis and soil-transmitted helminth control programme, a follow-up of children took place in eight sentinel sites. The objective of the study was to assess the evolution of Schistosoma haematobium infection and anaemia in schoolchildren after a single administration of praziquantel (PZQ) and albendazole. Pre-treatment examination and follow-up at one year post-treatment of schoolchildren aged 7, 8, and 11 years, including interview, urine examination, ultrasound examination of the urinary tract, and measurement of haemoglobin. Before treatment, the overall prevalence of S. heamatobium infection was 75.4% of the 1,642 enrolled children, and 21.8% of children excreted more than 50 eggs/10 ml urine. Prevalence increased with age. The overall prevalence of anaemia (haemoglobin <11.5 g/dl) was 61.6%, decreasing significantly with increasing age. The mean haemoglobinemia was 11 g/dl. In bivariate analysis, anaemia was significantly more frequent in children infected with S. haematobium, although it was not correlated to the intensity of infection. Anaemia was also associated with micro-haematuria and to kidney distensions. In a sub-sample of 636 children tested for P. falciparum infection, anaemia was significantly more frequent in malaria-infected children. In multivariate analysis, significant predictors of anaemia were P. falciparum infection, kidney distension, and the village. One year after a single-dose praziquantel treatment (administered using the WHO PZQ dose pole) co-administered with albendazole (400 mg single dose) for de-worming, the prevalence of S. haematobium infection was 38%, while the prevalence of anaemia fell to 50.4%. The mean haemoglobinemia showed a statistically significant increase of 0.39 g/dl to reach 11.4 g/dl. Anaemia was no longer associated with S. haematobium or to P. falciparum infections, or to haematuria or ultrasound abnormalities of the urinary tract. The high prevalence of anaemia in Nigerian children is clearly a result of many factors and not of schistosomiasis alone. Nevertheless, treatment of schistosomiasis and de-worming were followed by a partial, but significant, reduction of anaemia in schoolchildren, not explainable by any other obvious intervention.
    PLoS Neglected Tropical Diseases 02/2008; 2(5):e241. · 4.57 Impact Factor
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    ABSTRACT: Drug resistance has been shown to increase malaria mortality and morbidity in both community- and hospital-based studies. We investigated the association between two Plasmodium falciparum drug resistance-related molecular markers and clinical profiles of severe malaria in children hospitalised in Niger. PCR-RFLP analysis showed that the codon 108 mutation of the pfdhfr gene was positively linked to severe malarial anaemia. These findings are consistent with persistent parasite infection leading to unbalanced anaemia in young children. No significant relationship was found between the molecular markers and hypoglycaemia or hyperparasitaemia. Conversely, the pfcrt T76 mutation was found to be negatively associated with cerebral malaria and neurological symptoms, such as convulsions and coma. These results have implications for the strain-specific virulence hypothesis and for parasite fitness and evolution. Our findings are discussed in regard to the local malaria transmission level.
    Microbes and Infection 05/2007; 9(5):599-604. · 2.92 Impact Factor
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    ABSTRACT: In the framework of the Human Immunodeficiency Virus (HIV) surveillance, seroprevalence and behavioural survey was conducted in 2002 in Dirkou, a place of concentration of female sex workers (FSW) in Niger The global HIV seroprevalence found was 50% (CI at 95%: 40.6-59.36%). The behavioural survey revealed that 98% of FSW had heard about HIV whereas 78.7% know at least one HIV transmission way and 76.9% know at least one HIV prevention means. Only 33.3% declared using condom, what show that sensitisation efforts are needed to induce a behaviour change in FSW and their clients.
    Bulletin de la Société de pathologie exotique 04/2006; 99(1):49-51.
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    ABSTRACT: Malaria takes a heavy toll in Niger, one of the world's poorest countries. Previous evaluations conducted in the context of the strategy for the Integrated Management of Childhood Illness, showed that 84% of severe malaria cases and 64 % of ordinary cases are not correctly managed. The aim of this survey was to describe epidemiological, clinical and biological features of malaria among <5 year-old children in the paediatric department of the National Hospital of Niamey, Niger's main referral hospital. The study was performed in 2003 during the rainy season from July 25th to October 25th. Microscopic diagnosis of malaria, complete blood cell counts and measurement of glycaemia were performed in compliance with the routine procedure of the laboratory. Epidemiological data was collected through interviews with mothers. 256 children aged 3-60 months were included in the study. Anthropometrics and epidemiological data were typical of a very underprivileged population: 58% of the children were suffering from malnutrition and all were from poor families. Diagnosis of malaria was confirmed by microscopy in 52% of the cases. Clinical symptoms upon admission were non-specific, but there was a significant combination between a positive thick blood smear and neurological symptoms, and between a positive thick blood smear and splenomegaly. Thrombopaenia was also statistically more frequent among confirmed cases of malaria. The prevalence of severe malaria was 86%, including cases of severe anaemia among < 2 year-old children and neurological forms after 2 years of age. Overall mortality was 20% among confirmed cases and 21% among severe cases. The study confirmed that malaria was a major burden for the National Hospital of Niamey. Children hospitalized for malaria had an underprivileged background. Two distinctive features were the prevalence of severe malaria and a high mortality rate. Medical and non-medical underlying factors which may explain such a situation are discussed.
    Malaria Journal 02/2005; 4(1):10. · 3.49 Impact Factor
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    ABSTRACT: A national population-based survey was carried out in Niger in 2002 to assess HIV prevalence in the population aged 15-49 years. A two-stage cluster sampling was used and the blood specimens were collected on filter paper and tested according to an algorithm involving up to three diagnostic tests whenever appropriate. Testing was unlinked and anonymous. The refusal rate was 1.1% and 6056 blood samples were available for analysis. The adjusted prevalence of HIV was 0.87% (95% CI, 0.5-1.3%) and the 95% CI of the estimated number of infected individuals was 22 864-59 640. HIV-1 and HIV-2 represented, respectively, 95.6% and 2.9% of infections while dual infections represented 1.5%. HIV positivity rate was 1.0% in women and 0.7% in men. It was significantly higher among urban populations than among rural ones (respectively, 2.1% and 0.6%, P < 10(-6)). Using logistic regression, the variables significantly related to the risk of being tested positive for HIV were urban housing, increasing age and being either widowed or divorced. The estimate from the national survey was lower than the prevalence assessed from antenatal clinic data (2.8% in 2001). In the future, the representativeness of sentinel sites should be improved by increasing the representation of rural areas accounting for more than 80% of the population. Compared with other sub-Saharan countries, the HIV prevalence in Niger is still moderate. This situation represents a strong argument for enhancing prevention programmes and makes realistic the projects promoting an access to potent antiretroviral therapies for the majority.
    Tropical Medicine & International Health 11/2004; 9(11):1161-6. · 2.94 Impact Factor
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    Journal de la société de Biologie Clinique. 01/2004; 8:21-24.
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    A.Missohou, E. Talaki et Ibrahim M.L
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    ABSTRACT: ED#05-588 1 INTRODUCTION The domestic goat capra hircus is an important livestock species throughout the entire asian and african continents. Goats are an important resource for agricultural, economic, cultural and religious purposes. Their origin remains uncertain and controversial, and the history of their domestication is more complex than indicated by previous studies. Archaeological evidence indicates that goats were one of the first animals to be domesticated by man around ten thousands years ago, in the ganj-darch in the zagros mountain pastures (Zeder et al., 2000). However, a world wide survey of domestic goat mtdna diversity has identified a multiple maternal origin with a possible centre of origin in asia as well as in the fertile crescent region (Luikart et al., 2001). In their study, three major mtdna lineages were revealed while in a more recent study (Joshi et al., 2004) concerning indian domestic goats two additional lineages were observed. Apart from advances on the evolutionary and demographic history of humans and domesticated animals, these studies are also important for the management and conservation of today’s animal resources. Unfortunately, many livestock breeds are still weakly characterised to date especially locally adapted breeds. According Doutressoulle (1947), West Africa presents a unique geographic mixture of two basic types of goats, particularly adapted to the local environmental conditions : • Savanah or Sahel goats in the Sahel belt south of the Sahara, extending from lake Chad to Senegal. This type which is long legged and not resistant to trypanosomiasis is found in an area free of tsetse flies. • Dwarf and trypanotolerant goats in humid zones, extending from South-Senegal through Nigeria. Among these types, breed classification is still unclear. For instance, the red Sokoto Goat is classified as a Sahel type by Epstein (1971), a dwarf type by Doutressoulle (1947) and a crossbreed of both by Wilson (1992). The Guera Goat was first described by Kane (1995) simply as a breed from Mauritania. Moreover, some breeds are known by the same name in different places, but are phenotypically different from one place to another. Conversely, there are breeds that look alike but have different names in different places (ILRI, 1996). Our study concerns the characterisation of seven west African goat breeds : Casamance Goat (Kolda, Senegal); Labe Goat (Fouta Djallon, Guinea); Sahel Goat from Djoloff (Senegal) from Maradi (Niger) and fom Gorgol (Maurtania); red Sokoto Goat (Maradi, Niger) and Guera Goat (Atar, Mauritania) with six microsatellites and with the αs1-casein locus. This study contributes to the global Asian-Aust. J. Anim. Sci. Vol. 19, No. 9 : 0000 - 0000 September 2006 www.ajas.info Diversity and Genetic Relationships among Seven West African Goat Breeds A. Missohou*, E. Talaki and I. Maman Laminou Service de Zootechnie-Alimentation. Ecole Inter-Etats des Sciences et Médecine Vétérinaires Dakar-Sénégal, BP 5077 Dakar-Sénégal ABSTRACT : This study was carried out to determine the genetic relationship among seven west African goat breeds : Casamance Goat (Kolda, Senegal), Labe Goat (Fouta Djallon, Guinea), three Sahel Goat (Djoloff, Senegal ; Maradi, Niger; Gorgol, Mauritania) red Sokoto Goat (Maradi, Niger) and Guera goat (Atar, Mauritania).The polymorphism of six microsatellites and the αs1-casein locus was analysed. The six microsatellite loci were polymorphic with a mean number of alleles ranging from 2.71 to 4.0. At the αs1-casein locus, A and B were the most frequent alleles, which are known to be associated with a high level of protein synthesis. A neighbour-joining tree and a Principal Component Analysis were performed and the reliability of both methods was tested. Our study shows that the genetic relationships among the breeds analysed correspond to their geographical distribution and in addition, that the Labe Goat is strongly separated from the other breeds. Among the seven markers used, four have an effect on the distribution of breeds while three seem to be non informative. (Key Words : Goats, West Africa, Microsatellites, αs1-Casein, Genetic Relationship) * Corresponding Author: A. Missohou. Tel: +221-5751140, Fax: +221-8254283, E-mail: missohou@refer.sn Received November 29, 2005; Accepted March 18, 2006 Missohou et al., (2006) Asian-Aust. J. Anim. Sci. 19(9):0000-0000 ED#05-588 2 process initiated by the FAO to document the world’s Animal genetic resources. MATERIALS AND METHODS Sampling The sampling process is of great importance since it will determine the kind of inferences which can be made. In order to reflect the current genetic composition and to try to ensure that the animals chosen were unrelated, individuals were sampled in herds from different locations (breeding centres and surrounding areas of the main goat breeds of West Africa). Between 74 to 100 blood and milk samples were collected per breed in lactating goats from at least 30 different villages with an average distance of two to 10 km. Within these samples, 20 were chosen for microsatellite typing procedures (one per village). Dwarf samples were provided from Kolda (Casamance, Southern Senegal) for the Casamance Goat and from Fouta Djallon (Guinea) for the Labe Goat. The three Sahel Goat were provided from Djoloff (Central Senegal); from Maradi (Niger) and from Gorgol (Mauritania). The red Sokoto Goat and the Guera Goat were provided respectively from Maradi (Niger) and Atar (Mauritania) (Figure 1). The Casamance Goat and the Labe Goat are dwarf and trypanotolerant while the other breeds are long legged and trypanosusceptible. Blood and milk samples were frozen and were respectively sent to the Inter-States school of Veterinary medecine (EISMV), Dakar, Senegal and to the Laboratory of Biochemical Genetics and Cytogenetics (LGBC), INRA, France, for analysis. DNA was extracted by LABOGENA (Laboratory of genetic analysis for animal species). Microsatellites and αs1-casein polymorphism analysis were carried out respectively in EISMV and LGBC. DNA extraction, PCR amplification and electrophoresis of milk samples DNA was extracted from 10 ml of frozen blood as described by Jean-Pierre (l987). Eleven microsatellites chosen from the most polymorphic ones published by Luikart et al. (1999) were tested. In our samples, only six were polymorphic: ILSTS011, INRABERN172, MAF65, OarFCB20, OarFCB48 and SRCRSP9. References and annealing temperature are described in Luikart et al. (1999). PCR was carried out in 25 μl reactions containing 1-30 ng of template DNA, 100 μM of each dNTP, 0.1 μM of each primer, MgCl2 (25 mM), 1 U of Taq polymerase, 1×PCR Figure 1. Geographical location of milk and blood samples collected in the 7 west African goat breeds of this study. Missohou et al., (2006) Asian-Aust. J. Anim. Sci. 19(9):0000-0000 ED#05-588 3 Buffer (500 mM Tris-Hcl pH 7.2 at 25°C, 100 mM MgSO4, 1 mM DTT). Cycling involved initial denaturation at 95°C for 5 min, 35 cycles of 15 s at 95°C, 15 s at 55°C or 50°C and 30 s at 72°C and a final extension step at 72°C for 10 min using a Perkin Elmer Gene Amp PCR System 2400. The PCR products were typed by electrophoresis on polyacrylamide gels (10%) and allele identification was performed by silver staining (Budowle et al., 1991). The polymorphism of milk proteins was determined by isoelectric focusing according to Mahé and Grosclaude (1993). Statistical analysis Allele frequencies, estimates of heterozygosities (Ht = 1-Σ(⎯Pi2)), expected heterozygosities, F-statistics (Fis, Fit, Fst) and gene flow were calculated using the GENETIX package version 4.03 (Belkhir et al., 1998). The goat breeds studied were considered to be closely related and the main factor describing their genetic variability is random drift. Under this assumption, the Reynolds distance (Reynolds, 1983) is the most appropriate genetic distance to measure the degree of diversification (Eding et al., 1999, Laval et al., 2002). The Reynolds distances estimation, the neighbourjoining tree construction and bootstrap analysis were performed using the PHYLIP package (Felsenstein, 1993). Prior to multivariate analysis, we tested the congruence of loci following the two step procedure developed by Moazami-Goudarzi and Laloë (2002), because a consensus representation of breed relationships is not meaningful if single markers are not congruent. First, distance matrixes among all the breeds were generated for each locus and correlations estimated using the Mantel procedure (Mantel, 1967). Next, marker congruence was investigated by performing a Principal Component Analysis (PCA) on the matrix of correlations and a Kruskal-Wallis test (NPAR1WAY procedure; SAS Institute, 2000) on rank scores of standardized distances among breeds. The correlation circle produced by the analysis gives a visual representation of marker congruity, while a significant Kruskall-Wallis test indicates that a compromise structure exists because distances are unequal among breeds. If a compromise structure exists, then a PCA using all the markers will be meaningful. The contribution of each marker in the structure of the principal components have been computed to see if these components are due to the action of a few markers only or to the whole set of markers. All computations relative to PCA were performed with ADE-4 package (Chessel et al., 2004) of R software (Ihaka and Gentleman, 1996). RESULTS AND DISCUSSION Markers polymorphism A total of 34 distinct alleles were detected from the 137 goats studied with a mean number of alleles ranging from 2.71 to 4.0 (Table 1). Among the seven loci analysed, five private alleles were detected. These alleles were present with a relatively high frequency (15%) for three of them and low frequencies (2.5%) for the two others. Heterozygosities (Ht) for the seven loci ranged from 0.468 to 0.587 across breeds with an overall average of 0.534. The red Sokoto Goat had the highest heterozygosity (Hexp = 0.587) and the Casamance Goat the lowest (Hexp = 0.47). This polymorphism is comparable with results published by Luikart et al. (1999), Yang et al. (1999) Wang et al. (2004) and Chenyambuga et al. (2004) who also worked on the Casamance Goat (also called Djallonke) and on a long legged breed (Maure) but is lower than those published by Yan et al. (2004), Sun et al. (2004). Population differentiation was examined by fixation indices Fis, Fit and Fst for each locus and across all loci. On average, we observed no significant deficit of heterozygotes for each of the breeds analysed (Fis = -0.52 (p<0.001)) or for the whole population (Fit = -0.19 (p<0.001)). We can thus suggest that the consanguinity of the analysed samples is probably weak. The average of genetic differentiation among breeds, measured as the Fst value, was 21% (p<0.001) with all loci contributing significantly to this differentiation. Thus, seventy nine percent of the genetic diversity in the total population could be attributed to differences among individuals. This value is similar to the values reported for Swiss goat breeds, Fst = 0.170 (Saitbekova et al., 1999) and Sub-Saharian goats Fst = 0.146 (Chenyambuga et al., 2004) and is higher than the values reported for horses Fst = 0.078 (Cañon et al., 2000), river buffalo breeds Fst = 0.038 (Barker et al., 1997) or cattle Fst = 0.107 (Kantanen et al., 2000). The differences in allele frequencies may be due to migration, random genetic Table 1. Mean number of alleles per locus and average heterozygosity values of 7 West African goat breeds of this study Breed Mean number of alleles Average observed heterozygosity Average expected heterozygosity Casamance dwarf 2.86 0.880±0.274 0.468±0.106 Sahel goat, Senegal 2.86 0.730±0.329 0.423±0.167 Red sokoto 4.0 0.812±0.226 0.587±0.08 Sahel goat, Niger 3.14 0.686±0.310 0.518±0.138 Guera 2.86 0.882±0.263 0.542±.061 Sahel goat, Maurtania 3.28 0.708±0.372 0.492±0.223 Labe goat 2.7 0.799±0.183 0.534±0.073 Missohou et al., (2006) Asian-Aust. J. Anim. Sci. 19(9):0000-0000 ED#05-588 4 drift or mutations. In our study, the genetic migration would have played an important role between breeds of close geographical vicinity. The gene flow ranges from 0.46 to 6.21 between pairs of breeds. The greatest gene flow (Nem = 6.21) is between the Sahel Goat from Niger and red Sokoto Goat and the lowest is between the Labe Goat and other breeds (on average Nem = 0.65). Thus, the Labe Goat has maintained an important genetic isolation from all other breeds. αs1-Casein polymorphism The αs1-casein locus is characterized by a high qualitative and quantitative genetic variability. In particular, milk coagulation properties are strongly influenced by this locus (Grosclaude et al., 1987, 1994). The nucleotide sequence of the whole goat αs1-casein-encoding gene (CSN1S1) has been determined, and at least, 15 alleles have been characterized (Ramuno et al., 2004). They are distributed among seven different classes of variants (A, B, C, E, F, G and O) and associated with four different synthesis efficiencies ranging from 3.5 g/L (αs1-Cn A, B, C) to 0 g/L (αs1-Cn0) per allele (Grosclaude et al., 1994). In this study, among the 620 animals analysed, it is clear that αs1-cnA and αs1-CnB were the major alleles, while αs1-CnC, αs1-CnE and αs1-CnF were rare alleles present only in some breeds (Table 2). For example, the αs1-CnB frequency varied from 0.62 in the Guera Goat to 0.93 in the Sahel Goat from Mauritania. The relatively high frequency of the αs1-CnE (11%) in the Guera Goat is interesting. In addition, at the DNA level the null allele is detected with a high frequency 25%, while not observed or only in one animal in the Casamance Goat and in the Sahel Goat from Mauritania (data not shown). As these alleles have been reported to be highly present in European goat breeds (Grosclaude et al., 1994), the specific distribution pattern of αs1-casein in the Guera Goat (also known as Spanish Goat or Western Sahara Goat) could be explained by crossbreeding with Spanish breeds introduced in Mauritania throughout Western Sahara. It is important to specify that due to selection programs the frequencies of αs1-CnA, αs1-CnB and αs1-CnC have considerably increased during the last decade. For example, the frequency of these groups of alleles has increased from 20% (1985) to 83% (2000) for the Alpine breed. It is surprising to note that the most frequent variant in these African goats (αs1-B) is also the phylogenetically oldest variants reported (Grosclaude et al., 1994, Bevilacqua et al., 2002). Even if goats have multiple maternal origins, possibly arising through multiple independent domestications, Africa may likely be one of the centres of domestication (Luikart et al., 2001). Relation between breeds Genetic distances were significantly unequal among breeds (Kruskall-Wallis test, x2 = 41.55, 20 d.f, p-value = 0.003), indicating the existence of a multivariate compromise structure. The correlation circle (Figure 2) suggested that the markers are congruent. Since all the markers are clustered in the same half-circle, PCA was performed. Due to the fact that the first two principal components (PC) explained 73% of the total variation, the four others were not considered. The first PC accounts for 45% of the total variance and it clearly distinguished the Labe Goat from Senegalese breeds. The second PC accounted for 28% of the total variance and it clearly separated the Labe Goat Table 2. Allelic frequencies of αs1-casein in samples of the 7 west African goat breeds of this study Populations Locations N αs1-cn A B C,E,F Casamance goat Senegal 100 0.193 0.807 0.000 Sahel goat Senegal 100 0.06 0.923 0.015 Red sokoto goat Niger 74 0.132 0.811 0.019 Sahel goat Niger 75 0.211 0.778 0.011 Guera Mauritania 90 0.268 0.619 0.113 Sahel goat Mauritania 82 0.034 0.933 0.002 Labe goat Guinea 99 0.316 0.684 0.000 Figure 2. Correlation circle constructed from single-marker distances. Missohou et al., (2006) Asian-Aust. J. Anim. Sci. 19(9):0000-0000 ED#05-588 5 from Mauritanian breeds. When plotted in a twodimensional space (Figure 3), these two principal components revealed a pattern of association that was in concordance with the geographical origin of the breeds. Figure 4 shows a neighbour-joining tree constructed from the matrix of Reynolds distances. The genetic relationships among the breeds correspond to their geographical distribution. Thus, four groups could be distinguished. The Labe Goat is strongly separated from other breeds and the most robust feature of the topology concerned the Senegalese breeds that are clustered with a bootstrap value of 85% while the occurrence of the node of breeds from Niger or Mauritania was 60%. Whatever the method used, the seven breeds were clearly separated according to their geographical origin rather than their type or morphological grouping. This geographical grouping has also been reported in the recent study of Chenyambuga et al. (2004) who analysed 15 goat breeds from Europe, Asia, Middle east and eastern, southern and western Africa, with 19 microsatellites. In this study the separation between West African breeds and other African breeds was detectable at the third principal component which accounted for 9.1% of the total variance. Our study confirms this similarity but at a sub-regional scale. This alikeness between breeds of the same country rather than among types (trypanosusceptible, trypanotolerant) may suggest increasing crossbreeding as a consequence of increase in transhumance (due to drought episodes during these last decades) and farmers preference for larger animals. We confirmed the erosion of animal genetic diversity reported in other animal species from West Africa (Missohou and Adakal, 2004). MacHugh et al. (1997) and Hanotte et al. (2000; 2002) reported a declining north-tosouth gradient of male zebu introgression among taurine breeds of West Africa. This was illustrated with the N’Dama breed across Senegal, The Gambia, Guinea Bissau and Guinea. For example N’Dama samples from Gambia have an average of 8.6% alleles that are of zebu origin, against 1.5% in Guinea Bissau and 0.2% for samples from the Fouta Djallon mountain of Guinea. These results lead the authors to qualify this area as representative of the last remnants of pure N’Dama left in West Africa. We have obtained similar results with the Labe Goat which has very weak values of gene flow estimates and a strongly separated position. Thus, the Fouta Djallon mountain has a very specific status with possibly the “most” pure breeds. This is probably due to the fact that this region is not easily accessible and have specific breeding practices. Even if inferences among breeds made using a few number of markers should be interpreted with caution, our study confirms the need to define a higher priority for management strategies and conservation measures for specific breeds (dwarf) or specific regional breeding practices (Fouta Djallon mountains). With the publication of the bovine genome sequence, the next step will be the combined use of random neutral markers and expressed genes. Thus, it will be necessary to use methods that can be applied to various types of markers and to check if the increase in the number of markers is really improving the reliability of the typology analysis. ACKNOWLEDGEMENTS The authors are grateful to the German Cooperation Agency (DAAD) for providing the laboratory equipments to EISMV, to University Agency of Francophonie (Auf) for financing the proposal, to national research centres and extension services of Guinea, Mauritania, Niger and Senegal for their contribution to blood and milk sampling, to LABOGENA (Laboratory of genetic analysis for animal species, Jouy-en-Josas, France) for DNA extraction and to LGBC for its contribution to laboratory and data analysis. Figure 3. Scatterplot of principal component analysis of allelic frequencies of 7 west African goat breeds of this study. Figure 4. Phenogram showing genetic similarities among seven West African goat breeds from microsatellite and αs1-casein. This tree is constructed by the neighbor-joining method from the Reynolds distance. Numbers at the node represent the percentage of group’s occurrence in 500 bootstrap replicates. Missohou et al., (2006) Asian-Aust. J. Anim. 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    Asian-Australien Journal of Animal Science. 01/2003; 19(9-19 (9)).
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    IBRAHIM M. Laminou
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    ABSTRACT: La morphobiométrie fut la première méthode pour caractériser les animaux mais cette approche présente des limites à cause de l’effet de l’environnement (alimentation, climat, soin) sur les performances zootechniques des animaux. Les apports de la génétique biochimique ont offert des nouvelles perspectives en particulier grâce au typage par les groupes sanguins et les protéines du lait. Actuellement, la diversité génétique qui est le reflet du polymorphisme au niveau du génome est étudiée directement au niveau de l’ADN nucléaire. Les premières études concernant la caractérisation des caprins ouest-africains se limitaient à la description morphologique et aux groupes sanguins sans établir une liaison phylogénétique entre les races. L’existence de nouvelles générations de marqueurs génétiques susceptibles de caractériser les populations animales nous a conduit à réaliser cette étude. Elle nous a permis d’identifier et de mettre au point un certain nombre de marqueurs permettant d’identifier même en nombre réduit les populations. La poursuite de ces travaux avec un nombre de marqueur plus important et sur d’autres populations d’Afrique de l’Ouest pourrait permettre de mieux cerner la variabilité génétique et de déterminer les distances génétiques. Cela permettrait de raisonner plus efficacement les programmes d’amélioration génétique à l’échelle de la sous-région Ouest-africaine d’autant plus que ces populations ont de sérieux atouts à faire valoir en matière d’aptitude fromagère.
    Biologie, UCAD Sénégal, 06/2001, Degree: Diplome d'étude Approfondie, Supervisor: Pr. ayao Missohou

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