85 research outputs found
Survey of Bauxite Resources, Alumina Industry and the Prospects of the Production of Geopolymer Composites from the Resulting by-product
Get PDFContribution of cattle breeds to household livelihoods and food security in southern Mali
Get PDFIn recent decades, there has been a rapid shift in livestock breeds used in developing countries. Local breeds are increasingly being replaced by exotic breeds, leading to a loss of genetic resources. The introduction of more productive but less adapted exotic livestock breeds might offer opportunities. However, it may also pose threats to the livelihoods of poor farmers. In southern Mali, where cattle play an important role in the livelihoods of rural households, the endemic trypanotolerant NDama cattle, are increasingly replaced and crossbred with the larger and more milk yielding trypano-susceptible Fulani Zebu. Thus, the NDama cattle face serious threats of genetic erosion, despite their adaptive attributes. A systematic comparison of the endemic NDama cattle, Fulani Zebu cattle and their crosses under the same farming conditions is required to reveal whether farmers benefit from the introduction of Fulani Zebu cattle or are negatively affected by the replacement of NDama purebreds.
The overall objective of the study was, therefore, to evaluate and compare NDama cattle with Fulani Zebu and their crossbreds based on their performance and contribution to household economic benefits and food security, taking into account the production environment and farmer breeding strategies. Specific objectives were (i) to investigate the production objectives and trait and breed preferences of cattle keepers; (ii) to evaluate and compare the productive and economic performances of NDama cattle, Fulani Zebu cattle and their crossbreds in order to assess the comparative advantages of these breed groups for farmers; and (iii) to examine households food security and coping strategies, with a particular emphasis on the contribution of different cattle breeds.
The study was carried out in the communes of Sibirila and Garalo, which are located in the Sikasso region of southern Mali. A stratified random sampling based on cattle and breed ownership was applied for the selection of 258 households. The 160 households with a herd were grouped into four herd categories based on breed composition. Forty-five households with only oxen and 53 without cattle represented two additional herd categories. Data collection methods encompassed household interviews, herd surveys and focus group discussions. The herd surveys were carried out for 120 households to assess individual cows (n=770) performances using a cow progeny history survey and body condition scoring (BCS). Food security was assessed using a household dietary diversity score (HDDS), food consumption score (FCS), and modified household food insecurity access scale (mHFIAS). Gross margin, net benefit and cost benefit ratio were calculated for the assessment of economic performance and efficiency. Besides descriptive statistics, data were analysed using an exploded logit model, mixed linear models and non-parametric tests using the Statistical Analysis System (SAS).
Draught power and savings were the most important production objectives. Farmers reported a large body size as the most preferred trait, followed by fertility, draught ability and milk yield. NDama was valued for disease and drought tolerance and their good traction ability. Crossbreds were the favored breed group and were appreciated for milk yield and body size, similar to Fulani Zebu. Breed preferences were mainly explained by resistance to disease for NDama cattle and high market price for Fulani Zebu and crossbred cattle. Production objectives, trait and breed preferences were mainly influenced by farmers ethnicity and cultural background.
Results on cow individual performances showed a higher body condition for NDama compared to crossbred and Fulani Zebu cattle. Gross margin and the benefit-cost ratio were highest in Fulani Zebu herds, followed by crossbred herds due to higher revenue generated from cattle and milk sale from these herds. The higher cash revenue for the sale of cattle in crossbred and Fulani Zebu herds was explained by the higher offtake rate in these two herd categories and a 25 and 60% higher selling price for crossbred and Fulani Zebu, respectively, than for NDama cattle. When non-market benefits were included, economic performances between the herd categories were similar as shown by the similar net benefit per cattle.
Cattle ownership and breed group were important determinants of all household food security indicators. Households keeping Fulani Zebu and mixed herds had the highest FCS, which was mainly explained by their more frequent milk consumption compared to the other breed groups. HDDS and FCS were positively correlated with diversity of food crops cultivated on farm and household wealth and negatively correlated with cotton cultivation. Generally cattle herd ownership was strongly associated with improved household diet diversity and reduced vulnerability to food insecurity.
The results of the present study showed that the ongoing replacement of native NDama cattle by Fulani Zebu cattle and their crosses is contributing to an improved household economic situation and food security. Fulani Zebu and crossbred cattle are the most suitable options for market-oriented local and settled transhumant farmers, given their higher price and increased profitability. The NDama cattle remain a valuable breed for subsistence-oriented local farmers for whom non-market benefits from cattle such as saving play a considerable role. Further research is required to investigate possible ways of optimizing and organizing the ongoing process of crossbreeding between the NDama and Fulani Zebu cattle, with a more systematic crossbreeding and selection program in line with the farmers interest.In den letzten Jahrzehnten hat in den Entwicklungsländern eine schnelle Änderung bezüglich der verwendeten Nutztierrassen stattgefunden. Die Einführung von exotischen Nutztierrassen mit höherer Leistung, die aber weniger an die lokalen Umweltbedingungen angepasst sind, könnte zwar Vorteile bieten, aber auch Gefahren für den Lebensunterhalt der armen Bauern bergen. Im Süden Malis, werden die endemischen, trypanotoleranten NDama Rinder zunehmend durch die größeren trypanoanfälligen Fulani Zebu ersetzt oder mit ihnen gekreuzt. Damit besteht eine ernsthafte Bedrohung der genetischen Erosion für das NDama Rind. Ein systematischer Vergleich der endemischen NDama Rinder, Fulani Zebu-Rinder und ihrer Kreuzungen unter den gleichen Haltungsbedingungen im westlichen Afrika ist notwendig, um zu zeigen, ob Tierhalter Vorteile von der Einführung der Fulani Zebu-Rinder ziehen oder Nachteile durch die Verdrängung der NDama- Rinder haben.
Das übergeordnete Ziel der Arbeit war daher, NDama, Fulani Zebu und deren Kreuzung zu bewerten und miteinander zu vergleichen, basierend auf ihren Leistungen, ihrem Beitrag zum Lebensunterhalt und zur Ernährungssicherung der ländlichen Haushalte unter Berücksichtigung der Produktionsumgebung und der Zuchtziele der Tierhalter.
Die Datenerhebung wurde von Oktober 2012 bis April 2013 in den Gemeinden Sibirila und Garalo in der Region Sikasso im Süden Malis durchgeführt. Eine stratifizierte Zufallsstichprobe, basierend auf Rinderbesitz und Rasse, wurde für die Auswahl von 258 Haushalten angewendet. Methoden der Datenerhebung umfassten Haushaltinterviews, eine Herdenerhebung und Fokusgruppen-Diskussionen. Die Ernährungssicherheit von Haushalten wurde anhand eines Nahrungsmittelvielfalt-Scores (HDDS), eines Nahrungsmittelkonsum-Scores (FCS) und einer modifzierten household food insecurity access scale (mHFIAS) ermittelt. Der Bruttogewinn, der Reingewinn und das Kosten-Nutzen-Verhältnis wurden für die Beurteilung der wirtschaftlichen Leistung und Effizienz berechnet. Neben deskriptiven statistischen Methoden wurden die Daten mit einem exploded Logit-Model, einem gemischten linearen Model und nicht-parametrischen Tests analysiert.
Die Zugleistung der Tiere und Haltung der Tiere als Anlage waren die wichtigsten Produktionsziele. Die am meisten bevorzugte Eigenschaft war nach Meinung der Tierhalter die Körpergröße der Tiere, gefolgt von Fruchtbarkeit, Zugfähigkeit und Milchleistung. NDama Rinder wurden für ihre Toleranz gegen Krankheiten und Dürre und für ihre gute Zugleistung geschätzt. Kreuzungstiere waren die bevorzugte Rassegruppe und wurden, ähnlich wie Fulani Zebu, für ihren Milchertrag und ihre Körpergröße geschätzt. Die Bevorzugung von NDama Rindern wurde mit "Krankheitsresistenz", die Bevorzugung von Fulani Zebu Rindern und Kreuzungstieren wurde mit "hoher Marktpreis" begründet. Produktionsziele, Merkmals- und Rassepräferenzen wurden hauptsächlich von der ethno-kulturellen Zugehörigkeit (einheimische Bambara Bauern und sesshaft gewordene Fulani Hirten) beeinflusst.
Ergebnisse zur individuellen Kuhleistung zeigten eine bessere Körperverfassung und eine niedrigere Abkalbe- und Verkaufsrate der NDama Rinder im Vergleich zu Fulani Zebu Rindern und ihrer Kreuzung. Die Abkalbe-und Verkaufsrate waren bei den Fulani Zebu- und Kreuzungstierherden höher als bei NDama Herden. Der Bruttogewinn und das Kosten-Nutzen-Verhältnis waren am höchsten in der Zebuherde, gefolgt von der Kreuzungstierherde. Dies wurde durch höhere Einnahmen aus Tier- und Milchverkäufen aus diesen Beständen erklärt. Die höheren Einnahmen beim Viehverkauf aus Herden mit Kreuzungstieren und Fulani Zebu erklärten sich durch höhere Verkaufsraten und einen 25% bzw. 60% höheren Verkaufspreis bei Kreuzungs- bzw. Fulani Zebu-Tieren im Vergleich zu NDama-Tieren. Wenn nicht-marktbezogene Vorteile berücksichtigt wurden, ähneln sich die Wirtschaftsleistungen aller Herden- Kategorien, wie aus dem gleichwertigen Nettonutzen pro Tier hervorgeht.
Rinderbesitz und Herden-Kategorie waren wichtige Determinanten für alle Ernährungs-sicherheitsindikatoren der Haushalte. Haushalte, die Fulani Zebu und gemischte Herden halten, hatten die höchste FCS, was vor allem durch ihren häufigeren Milchkonsum erklärt werden konnte. HDDS und FCS waren positiv mit der Vielfalt der auf dem Betrieb angebauten Nahrungspflanzen und dem Vermögen der privaten Haushalte korreliert und negativ korreliert mit dem Baumwollanbau. In der Regel war der Besitz einer Rinderherde eng mit einer verbesserten Ernährungsvielfalt der Haushalte und einer reduzierten Anfälligkeit für Ernährungsunsicherheit verbunden.
Die Ergebnisse der Arbeit zeigen auch, dass die derzeitige Verdrängung der heimischen NDama Rinder durch Fulani Zebu Rinder und ihrer Kreuzungen zu einer verbesserten wirtschaftlichen Situation und Nahrungssicherung der Haushalte beitragen. Fulani Zebu und Kreuzungstiere sind aufgrund ihrer höheren Preise und höherer Profite die geeignetsten Optionen für marktorientierte, sesshaft gewordene Fulani Hirten. Das NDama Rind bleibt eine wertvolle Rasse für die subsistenzorientierten lokalen Bauern, für die nicht marktabhängigen Vorteile von Rindern, wie ihre Nutzung als finanzielle Anlage, eine erhebliche Rolle spielen. Weitere Forschung ist erforderlich, um den laufenden Prozess der Kreuzung zwischen den NDama und Fulani Zebu-Rindern zu optimieren durch eine systematischere Kreuzungszucht und Zuchtprogramme, die im Einklang mit den Interessen der Tierhalter stehen
Traitement Chirurgical Des Eventrations Abdominales Avec Pose De Prothese: Experience A Court Terme Du Chu Yalgado Ouedraogo
Get PDFTitle: Surgical management of abdominal incisional hernia with mesh placement: short- term experience of the University Hospital Yalgado Ouedraogo Introduction: The incisional hernia repair has several variants depending on the implantation site of the mesh. It may be intraperitoneal, preperitoneal, pre-mucosal or pre-musculoskeletal. Objective: The aim of the work was to report at short term the experience of the general and digestive surgery service of the Yalgado Ouédraogo University Hospital Center for the surgical management of abdominal incisional hernia with mesh placement in retro-muscular prefascial Patients and methods: This was a cross-sectional and descriptive study with a review of the files and a survey of 17 patients operated on for voluminous abdominal incisional hernia (diameter greater than 10 cm) from September 1, 2014 to August 31, 2015. Results: The mean duration of hospitalization was 7 days with extremes of 4 and 15 days. The dressings lasted on average 7 days with extremes of 4 and 15 days. The suction drains remained in place on average 8.56 days with extremes of 5 and 14 days and the mean duration of the abdominal wall contusion was 24.5 days with extremes of 10 and 40 days. The early postoperative complications were minor: 8 seromas, 1 hematomas, 1 superficial infection of the wall. Patients were followed for an average duration of 9.47 months with extremes of 4 and 14 months. The complications during this period were: 3 minor residual pain (limited to the scar) and 1 recurrence. Thirteen patients (76.5%) were satisfied with the intervention. Mortality was zero. Conclusion: Short time complications related to the surgical management of abdominal incisional hernia with mesh placement in retro-muscular prefascial in CHUYO are mainly minor
Hydric stress-dependent effects of Plasmodium falciparum infection on the survival of wild-caught Anopheles gambiae female mosquitoes
Get PDF<p>Abstract</p> <p>Background</p> <p>Whether <it>Plasmodium falciparum</it>, the agent of human malaria responsible for over a million deaths per year, causes fitness costs in its mosquito vectors is a burning question that has not yet been adequately resolved. Understanding the evolutionary forces responsible for the maintenance of susceptibility and refractory alleles in natural mosquito populations is critical for understanding malaria transmission dynamics.</p> <p>Methods</p> <p>In natural mosquito populations, <it>Plasmodium </it>fitness costs may only be expressed in combination with other environmental stress factors hence this hypothesis was tested experimentally. Wild-caught blood-fed <it>Anopheles gambiae </it>s.s. females of the M and S molecular form from an area endemic for malaria in Mali, West Africa, were brought to the laboratory and submitted to a 7-day period of mild hydric stress or kept with water ad-libitum. At the end of this experiment all females were submitted to intense desiccation until death. The survival of all females throughout both stress episodes, as well as their body size and infection status was recorded. The importance of stress, body size and molecular form on infection prevalence and female survival was investigated using Logistic Regression and Proportional-Hazard analysis.</p> <p>Results</p> <p>Females subjected to mild stress exhibited patterns of survival and prevalence of infection compatible with increased parasite-induced mortality compared to non-stressed females. Fitness costs seemed to be linked to ookinetes and early oocyst development but not the presence of sporozoites. In addition, when females were subjected to intense desiccation stress, those carrying oocysts exhibited drastically reduced survival but those carrying sporozoites were unaffected. No significant differences in prevalence of infection and infection-induced mortality were found between the M and S molecular forms of <it>Anopheles gambiae</it>.</p> <p>Conclusions</p> <p>Because these results suggest that infected mosquitoes may incur fitness costs under natural-like conditions, they are particularly relevant to vector control strategies aiming at boosting naturally occurring refractoriness or spreading natural or foreign genes for refractoriness using genetic drive systems in vector populations.</p
Hydric stress-dependent effects of Plasmodium falciparum infection on the survival of wild-caught Anopheles gambiae female mosquitoes
Get PDF<p>Abstract</p> <p>Background</p> <p>Whether <it>Plasmodium falciparum</it>, the agent of human malaria responsible for over a million deaths per year, causes fitness costs in its mosquito vectors is a burning question that has not yet been adequately resolved. Understanding the evolutionary forces responsible for the maintenance of susceptibility and refractory alleles in natural mosquito populations is critical for understanding malaria transmission dynamics.</p> <p>Methods</p> <p>In natural mosquito populations, <it>Plasmodium </it>fitness costs may only be expressed in combination with other environmental stress factors hence this hypothesis was tested experimentally. Wild-caught blood-fed <it>Anopheles gambiae </it>s.s. females of the M and S molecular form from an area endemic for malaria in Mali, West Africa, were brought to the laboratory and submitted to a 7-day period of mild hydric stress or kept with water ad-libitum. At the end of this experiment all females were submitted to intense desiccation until death. The survival of all females throughout both stress episodes, as well as their body size and infection status was recorded. The importance of stress, body size and molecular form on infection prevalence and female survival was investigated using Logistic Regression and Proportional-Hazard analysis.</p> <p>Results</p> <p>Females subjected to mild stress exhibited patterns of survival and prevalence of infection compatible with increased parasite-induced mortality compared to non-stressed females. Fitness costs seemed to be linked to ookinetes and early oocyst development but not the presence of sporozoites. In addition, when females were subjected to intense desiccation stress, those carrying oocysts exhibited drastically reduced survival but those carrying sporozoites were unaffected. No significant differences in prevalence of infection and infection-induced mortality were found between the M and S molecular forms of <it>Anopheles gambiae</it>.</p> <p>Conclusions</p> <p>Because these results suggest that infected mosquitoes may incur fitness costs under natural-like conditions, they are particularly relevant to vector control strategies aiming at boosting naturally occurring refractoriness or spreading natural or foreign genes for refractoriness using genetic drive systems in vector populations.</p
Effets de la Politique Fiscale Sur la Croissance Économique du Mali
Get PDFL’objectif de cette étude était d’examiner les effets de la politique fiscale sur la croissance économique au Mali durant la période 1990-2021, en utilisant le modèle autorégressif à décalage distribué (ARDL), principalement en raison de l'ordre d'intégration des variables utilisées. Les résultats empiriques ont révélé qu'il existe une relation positive entre les instruments de politique fiscale (impôt sur le revenu et dépenses publiques) et la croissance économique. Sur la base des résultats, l'étude recommande au gouvernement de faire la distinction entre les dépenses productives et improductives et d'augmenter les dépenses. L'implication de ces résultats est que l'économie du Mali est susceptible d'être plus performante si davantage de ressources sont détournées de la consommation du gouvernement vers les dépenses d'investissement.
The objective of this study was to examine the effects of fiscal policy on economic growth in Mali during the period 1990-2021, using the autoregressive distributed lag model (ARDL), mainly because of the order of integration of the variables used. The empirical results revealed that there is a positive relationship between fiscal policy instruments (income tax and government spending) and economic growth. Based on the results, the study recommends that the government distinguish between productive and unproductive expenditures and increase spending. The implication of these results is that Mali's economy is likely to perform better if more resources are diverted from government consumption to investment spending
Effets de la Politique Fiscale Sur la Croissance Économique du Mali
Get PDFL’objectif de cette étude était d’examiner les effets de la politique fiscale sur la croissance économique au Mali durant la période 1990-2021, en utilisant le modèle autorégressif à décalage distribué (ARDL), principalement en raison de l'ordre d'intégration des variables utilisées. Les résultats empiriques ont révélé qu'il existe une relation positive entre les instruments de politique fiscale (impôt sur le revenu et dépenses publiques) et la croissance économique. Sur la base des résultats, l'étude recommande au gouvernement de faire la distinction entre les dépenses productives et improductives et d'augmenter les dépenses. L'implication de ces résultats est que l'économie du Mali est susceptible d'être plus performante si davantage de ressources sont détournées de la consommation du gouvernement vers les dépenses d'investissement.
The objective of this study was to examine the effects of fiscal policy on economic growth in Mali during the period 1990-2021, using the autoregressive distributed lag model (ARDL), mainly because of the order of integration of the variables used. The empirical results revealed that there is a positive relationship between fiscal policy instruments (income tax and government spending) and economic growth. Based on the results, the study recommends that the government distinguish between productive and unproductive expenditures and increase spending. The implication of these results is that Mali's economy is likely to perform better if more resources are diverted from government consumption to investment spending
The contribution of aestivating mosquitoes to the persistence of Anopheles gambiae in the Sahel
Get PDF<p>Abstract</p> <p>Background</p> <p>Persistence of African anophelines throughout the long dry season (4-8 months) when no surface waters are available remains one of the enduring mysteries of medical entomology. Recent studies demonstrated that aestivation (summer diapause) is one mechanism that allows the African malaria mosquito, <it>Anopheles gambiae</it>, to persist in the Sahel. However, migration from distant localities - where reproduction continues year-round - might also be involved.</p> <p>Methods</p> <p>To assess the contribution of aestivating adults to the buildup of populations in the subsequent wet season, two villages subjected to weekly pyrethrum sprays throughout the dry season were compared with two nearby villages, which were only monitored. If aestivating adults are the main source of the subsequent wet-season population, then the subsequent wet-season density in the treated villages will be lower than in the control villages. Moreover, since virtually only M-form <it>An. gambiae </it>are found during the dry season, the reduction should be specific to the M form, whereas no such difference is predicted for S-form <it>An. gambiae </it>or <it>Anopheles arabiensis</it>. On the other hand, if migrants arriving with the first rain are the main source, no differences between treated and control villages are expected across all members of the <it>An. gambiae </it>complex.</p> <p>Results</p> <p>The wet-season density of the M form in treated villages was 30% lower than that in the control (P < 10<sup>-4</sup>, permutation test), whereas no significant differences were detected in the S form or <it>An</it>. <it>arabiensis</it>.</p> <p>Conclusions</p> <p>These results support the hypothesis that the M form persist in the arid Sahel primarily by aestivation, whereas the S form and <it>An. arabiensis </it>rely on migration from distant locations. Implications for malaria control are discussed.</p
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