Science.gov

Sample records for madagascar

  1. Madagascar.

    PubMed

    1987-08-01

    Madagascar, in the Indian Ocean near Mozambique, is officially known as the Democratic Republic of Madagascar. This republic has 3 branches of government and includes 6 provinces or subdivisions. Since 1981, it has received more than $62 million in grants and concessional sales from the US. There have been other types of assistance as well, including a development assistance program begun in 1985. Its population is largely of mixed Asian and African origin. There exists an historic rivalry between the Catholic coastal people, Cotiers, and the Protestant Merina, who predominate in civil service, business, and the professions. To combat this, the government has set one of its goals to be the highlighting of nationalism. The beginning of Madagascar's written history can be traced to when the Arabs established trading posts along the coastal areas. Eventually, Madagascar moved toward independence from the French and became an autonomous state in 1958. The president is elected for a 7-year term and is the head, during that time, of the Supreme Revolutionary Council. There is a 3-tiered court system, including a lower court for civil and criminal cases, a criminal court for more serious crimes, and a supreme court. The government represents a strong socialist philosophy and outright criticism of the President and his government is not tolerated. The economy of Malagasy is dominated by agriculture, which employs about 85% of the population. Although it faces some serious problems in the areas of foreign exchange and imports/exports, Madagascar is a potentially prosperous country. It boasts diversified agricultural production, it is rich in minerals, and it maintains strong commercial ties to the West. Madagascar's major trading partners are France, the US, the Federal Republic of Germany, the Soviet Union, Qatar, and Japan. Madagascar maintains the Popular Armed Forces for its defense; however, there is a heavy reliance on the Soviet Union for military equipment and

  2. Deforestation, Madagascar

    NASA Image and Video Library

    1989-11-27

    STS033-82-103 (22-27 Nov. 1989) --- This oblique view of the southern half of Madagascar was taken by the crew members of the Space Shuttle Discovery as they orbited Earth at an altitude of 289 nautical miles.

  3. Deforestation, Madagascar

    NASA Image and Video Library

    1990-04-29

    This high oblique view shows the majority of the island of Madagascar (19.0S, 47.5E). This Texas sized island is now largely deforested and is suffering from severe soil erosion as well as a declining biological species diversity and productivity. At the turn of the century, the island was almost totally forested but now, forests cover only about 10 percent of the surface. Evidence of soil erosion can be seen in the offshore sediment plumes.

  4. Trigonalidae (Hymenoptera) of Madagascar

    USDA-ARS?s Scientific Manuscript database

    Seven species of the primarily hyperparasitoid family Trigonalidae are reported from Madagascar: Orthogonalys brevis Smith and Tripotin, sp. n., Orthogonalys gigantea Benoit, 1951; O. hova Bischoff, 1933; O. maculata Bischoff, 1933; Orthogonalys parahova Smith and Tripotin, sp. n., O. seyrigi Bisch...

  5. Betsiboka River Valley, Madagascar

    NASA Image and Video Library

    1983-06-24

    STS007-03-058 (18-24 June 1983) --- The Island of Madagascar in the Indian Ocean off the coast of Africa. The colorful area is the mouth of the Betsiboka River near the city of Majunga. The photograph was taken with a 70mm handheld camera aimed through the aft flight deck?s overhead windows on the Earth-orbiting Space Shuttle Challenger.

  6. Onilahy River, Madagascar

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Near the southern tip of Madagascar, the Onilahy River (23.5S, 44E) drains a near barren landscape, the result of rapid deforestation for quick profits from the lumber industry with no regard to the environmental impact. At the turn of the century, the island was a lush tropical paradise with about 90 percent of the surface forested. Now, at the close of the century, only about 10 percent of the forests remain in inaccessible rugged terrain.

  7. Oceanography of West Madagascar

    NASA Astrophysics Data System (ADS)

    John, Bemiasa

    2014-05-01

    During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Along selected hydrographical transects, a total of 182 CTD stations were conducted and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, along the west and south coast of Madagascar, the shelf is narrow and widen slightly along the north-west coast. In all ten transects the isotherms showed stratified waters from the coast to offshore. A maximum salinity layer was observed at subsurface in all transects. Dissolved oxygen had a maximum at around 500 m depth in all transects. Low fluorescence values were observed in the upper 150-200 m, with maximum values in the range of 0.14-0.22 µg/l at intermediate layers. The conditions were consistent along and between the transects, with more variation observed at transect 9. No upwelling was observed along the western coast. The surface temperature (5 m depth) increased from 22°C in the south to 26°C in the north. The horizontal distribution of surface salinities showed homogenous conditions with values between 35.4psu (south) and 35.0 psu (north). Also starting from the coast to offshore, both the surface temperatures and surface salinities showed homogenous patterns.

  8. Zooplankton of West Madagascar

    NASA Astrophysics Data System (ADS)

    Bemiasa, John; Remanevy, Sitraka

    2014-05-01

    During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Zooplankton samples were collected with Hydrobios Multinet at all environmental stations ranging from 200 m depth to the surface. The Multinet was equipped with 5 nets for depth-stratified sampling. The nets were fitted with 180 µm mesh size and the water flow through the nets was measured. The Multinet was deployed and retrieved at a rate of ~ 1.5 m per second and was obliquely hauled. The five nets were triggered at the pre-selected depth intervals 0-25m, 25-50m, 50-80m, 80-120m and 120-200m. All samples were stored in marked bottles and preserved with buffered formaldehyde of 4% for further analysis. As results,the zooplankton abundance was influenced by physico-chemical factors. During the study period 34 Family of zooplankton were identified which are dominated by Copepoda (58,69%) followed by Radiolaria (12,06%), Appendicularia (6,47%), Sagitta (5,11%), Larvae (4,57%), Ostracoda (3,13%), pelagic Foraminifera (2,15%). Family of zooplankton with abundance <1% were also recorded, namely Salpidae (0,94%), Euphausiacea (0,44%), Tintinnidae (0,39%), Annélidae Polychètes (0,34%), Mysidacea (0,21%), Ptéropodae (0,13%). Highest number of zooplankton were found at the depth below the maximum of fluorescence during the day. Copepods distribution depends on site and depth. During this study, the number of identified species is always superior to 50 for all sampling sites. The findings of the present study will help to improve the scientific knowledge of the marine ecosystem of the west coast of Madagascar.

  9. [Latrodectism in Madagascar].

    PubMed

    Ramialiharisoa, A; de Haro, L; Jouglard, J; Goyffon, M

    1994-01-01

    Data concerning lactrodectism in Madagascar is scarce. Two spider species of the Latrodectus genus are found on the Grand Isle: the black widow Latrodectus mactans mena vody and the brown widow Latrodectus geometricus. From March 1991 through July 1992, 10 cases of envenomation by these spiders were treated in the Intensive Care Unit of Antananarivo Hospital. Symptomatology was remarkable with regard to severity (one fatality due to cardiovascular failure, one gangrene of the foot) as well as clinical manifestations (immediate local pain, kidney dysfunction, arterial hypertension). In two cases, the spider was captured and identified. Both were female brown widows (Latrodectus geometricus), which might explain the differences observed in comparison with the classic features of latrodectism that have been established from American and European black widow bites. Since antivenom was unavailable, only symptomatic treatment was administered, including intravenous calcium that proved effective for pain relief.

  10. Oceanography of East Madagascar

    NASA Astrophysics Data System (ADS)

    Bemiasa, John

    2014-05-01

    During six week survey (August - September 2008) in Southern and Eastern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. A total of 102 CTD stations were conducted along selected hydrographical transects and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, the first section between latitude 25o-26oS showed sea surface temperature values ranging between 25oC to 15oC upper 250m depth. As part of the south-west, the shelf is narrow and widen slightly along the tip south of the Island coast. In contrast of the west coast, in all transects performed along the south and the east coast, in most cases, the isotherms showed non stratified waters from the coast to offshore. The presence of the upwelling system in the south-east coast modifies drastically the patterns of all measured parameters. Fluorescence had a maximum values (0.25 µg/l) at surface near the coast in 2nd to 5th transects. Inversely, low temperature values were observed along the south and south-east with minimum values in the range of 18. 5oC-11oC at 50-250 m depth. These conditions were consistent along and between the 2nd to 5th transects, with more variation observed at transect 5. The salinity values (5 m depth) decreased from 35.7 psu in the south to 34.5 psu in the east. The horizontal distribution of oxygen showed non homogenous conditions with values between 5 ml/l (south) and 2.5 ml/l (south-east). Also starting from the coast to offshore, surface temperatures and surface salinities, surface

  11. Logistical teamwork tames Madagascar wildcats

    SciTech Connect

    Twa, W.

    1986-03-01

    Amoco Production Company's exploration program in western Madagascar's Sakalaya coastal plain exemplifies the unique logistical challenges both operator and drilling contractor must undergo to reach the few remaining onshore frontier areas. Sakalava is characterized by deep rivers, flood prone tributaries, and a lone 40 km hard-surface road. Problems caused by a lack of port facilities and oil field services are complicated by thousands of square miles of unimproved wooded plains. Rainwater from the nearby mountains of central Madagascar frequently floods rivers in the Sakalava coastal plain leaving impassable marshes in their wake. Prior to this project, about 45 wells had been drilled in Madagascar. Most recently, state oil company Omnis contracted Bawden Drilling International Inc. to drill nine wells for its heavy oil project on the Tsimioro oil prospect. Bawden provided both logistical and drilling services for that program.

  12. Resistances et initiatives a Madagascar (Resistance and Initiatives in Madagascar).

    ERIC Educational Resources Information Center

    Georges, Claude

    1993-01-01

    Discusses the cultural, political, and institutional barriers to population education in Madagascar and the strategies and initiatives that have been adopted to overcome them, including emphasizing the national character of a project, accommodating the values and ideals of the people involved, and assuring teachers of their classroom autonomy.…

  13. The Lithospheric Structure of Madagascar

    NASA Astrophysics Data System (ADS)

    Wysession, M. E.; Pratt, M. J.; Andriampenomanana Ny Ony, F. S. T.; Tsiriandrimanana, R.; Nyblade, A.; Aleqabi, G. I.; Shore, P.; Tucker, R.; Wiens, D. A.; Rambolamanana, G.

    2016-12-01

    The lithosphere of Madagascar is revealed for the first time from a combination of studies using data from the 2011-2013 MACOMO (Madagascar, the Comoros, and Mozambique) broadband seismic array from the IRIS PASSCAL program (funded by NSF, with additional data from the RHUM-RUM and Madagascar Seismic Profile projects). Methods include seismicity locations, body-wave receiver functions, Pn tomography, body-wave tomography, and ambient-noise and two-plane-wave earthquake surface-wave analyses. Madagascar's crustal thickness varies greatly, from 20 to 45 km, in good agreement with its past tectonic history of rifting from the mainland and having India break away to the north. The crust is thickest along the central spine of the island, along a ridge of mountains, but unusually high elevations suggest some amount f thermal buoyancy in the mantle. Crust is also thick along the east coast, where archean terranes were severed from India. Crust is thinnest along the west coast, where thick sedimentary basins up to 8 km thick are found on top of unusually thinned basement crust (about 12 km thick), a remnant of rifting away from Africa 130-160 Ma ago. Madagascar has an unusually high level of intraplate seismicity, with 918 earthquakes located during the 2-year period. Seismicity shows interesting correlations with paleotectonic features, but much is located in the central regions of the island, associated with normal faulting along several graben structures. This region also corresponds to the central of three regions within Madagascar (north, central, and southwest) that display strong lithospheric seismic low-velocity anomalies that underlie regions of current or recent volcanic activity. Surface waves show that these low-velocity zones (LVZs) extending down into the asthenosphere, and body-wave tomography shows them extending even deeper. Pn tomography shows that the width of the central LVZ is only about 100-200 km in diameter at the top of the mantle, indicative of

  14. Atmospheric Effects of Biomass Burning in Madagascar

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.; Hoegy, Walter R.; Ziemke, Jerry R.; Thorpe, Arthur; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Simultaneous tropospheric ozone and aerosols observed using the TOMS satellite instrument are reported for Madagascar during the 1979 through 1999 time period Ozone observations made using the TOMS tropospheric ozone convective-cloud differential method show that the tropospheric ozone amount associated with Madagascar has an average monthly value of 30 DU (Dobson units). The average value is enhanced by 10 to 15 DU in October This maximum coincides with the time of maximum biomass area burning in Madagascar and parts of southern Africa. The aerosol index derived from TOMS is examined for correlation with biomass burning in Madagascar and southern Africa. There is good correlation between a satellite observation derived fire index for different parts of Madagascar, tropospheric ozone and the TOMS aerosol index in the same geographical area. Aerosols from fires were found to reach their peak in November and to persist over Madagascar until sometime in December.

  15. Continental Deformation in Madagascar from GNSS Observations

    NASA Astrophysics Data System (ADS)

    Stamps, D. S.; Rajaonarison, T.; Rambolamanana, G.; Herimitsinjo, N.; Carrillo, R.; Jesmok, G.

    2015-12-01

    D.S. Stamps, T. Rajaonarison, G. Rambolamanana Madagascar is the easternmost continental segment of the East African Rift System (EARS). Plate reconstructions assume the continental island behaves as a rigid block, but studies of geologically recent kinematics suggest Madagascar undergoes extension related to the broader EARS. In this work we test for rigidity of Madagascar in two steps. First, we quantify surface motions using a novel dataset of episodic and continuous GNSS observations that span Madagascar from north to south. We established a countrywide network of precision benchmarks fixed in bedrock and with open skyview in 2010 that we measured for 48-72 hours with dual frequency receivers. The benchmarks were remeasured in 2012 and 2014. We processed the episodic GNSS data with ABPO, the only continuous GNSS station in Madagascar with >2.5 years of data, for millimeter precision positions and velocities at 7 locations using GAMIT-GLOBK. Our velocity field shows 2 mm/yr of differential motion between southern and northern Madagascar. Second, we test a suite of kinematic predictions from previous studies and find residual velocities are greater than 95% uncertainties. We also calculate angular velocity vectors assuming Madagascar moves with the Lwandle plate or the Somalian plate. Our new velocity field in Madagascar is inconsistent with all models that assume plate rigidity at the 95% uncertainty level; this result indicates the continental island undergoes statistically significant internal deformation.

  16. The separation of madagascar and Africa.

    PubMed

    Rabinowitz, P D; Coffin, M F; Falvey, D

    1983-04-01

    Identification of a sequence of east-west trending magnetic anomalies of Mesozoic age in the western Somali Basin helps define the position of Madagascar in the Gondwana reconstruction. The anomalies are symmetric about ancient ridge segments and are flanked to the north and south by the Jurassic magnetic quiet zone. The motion of Madagascar relative to Africa was from the north and began in the middle Jurassic, about the same time as the initial breakup of Gondwanaland. Sea-floor spreading ceased when Madagascar assumed its present position in the Early Cretaceous.

  17. A rehabilitation training partnership in Madagascar.

    PubMed

    Andrianabela, Sonia; Hariharan, Ram; Ford, Helen L; Chamberlain, M Anne

    2015-09-01

    We describe here the development of a mid-level training programme for doctors in Madagascar to direct regional and national rehabilitation services. Eight doctors enrolled and all gained their diplomas and have gone on to form the Association of Physical and Rehabilitation Medicine of Madagascar, which is leading further training and service developments. The course was specific to Madagascar's needs, and was devised according to the vision of the senior rehabilitation specialist in the Ministry of Health in Madagascar with support from the University of Antananarivo. The syllabus was developed with a senior Rehabilitation Medicine consultant responsible for setting up a comprehensive range of services and teaching in a University teaching hospital in the UK. Major barriers to success include the economic and political situation in Madagascar, which worsened steadily over the period of the training, the lack of resources for health, rehabilitation and rehabilitation workshops, and the withdrawal of aid. The sustainability of the training and the improved services that have been initiated will be evaluated, but these will be influenced by the situation of the country. It is hoped that this description of a highly practical training using modern teaching methods will be of use in other low-resource countries. Much of the teaching input was given by clinicians from a UK teaching hospital, and this resource will continue to be needed.

  18. Asystasia mosaic Madagascar virus: a novel bipartite begomovirus infecting the weed Asystasia gangetica in Madagascar.

    PubMed

    De Bruyn, Alexandre; Harimalala, Mireille; Hoareau, Murielle; Ranomenjanahary, Sahondramalala; Reynaud, Bernard; Lefeuvre, Pierre; Lett, Jean-Michel

    2015-06-01

    Here, we describe for the first time the complete genome sequence of a new bipartite begomovirus in Madagascar isolated from the weed Asystasia gangetica (Acanthaceae), for which we propose the tentative name asystasia mosaic Madagascar virus (AMMGV). DNA-A and -B nucleotide sequences of AMMGV were only distantly related to known begomovirus sequence and shared highest nucleotide sequence identity of 72.9 % (DNA-A) and 66.9 % (DNA-B) with a recently described bipartite begomovirus infecting Asystasia sp. in West Africa. Phylogenetic analysis demonstrated that this novel virus from Madagascar belongs to a new lineage of Old World bipartite begomoviruses.

  19. Pneumonic Plague Outbreak, Northern Madagascar, 2011

    PubMed Central

    Richard, Vincent; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Scholz, Holger C.; Rajerison, Minoarisoa

    2015-01-01

    Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Madagascar-specific 1.ORI3-k single-nucleotide polymorphism genotype and 4 clustered regularly interspaced short palindromic repeat patterns. This outbreak had a case-fatality rate of 100% for nontreated patients. The Y. pestis 1.ORI3-k single-nucleotide polymorphism genotype might cause larger epidemics. Multidrug-resistant strains and persistence of the pathogen in natural foci near human settlements pose severe risks to populations in plague-endemic regions and require outbreak response strategies. PMID:25530466

  20. Pneumonic plague outbreak, Northern Madagascar, 2011.

    PubMed

    Richard, Vincent; Riehm, Julia M; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Scholz, Holger C; Rajerison, Minoarisoa

    2015-01-01

    Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Madagascar-specific 1.ORI3-k single-nucleotide polymorphism genotype and 4 clustered regularly interspaced short palindromic repeat patterns. This outbreak had a case-fatality rate of 100% for nontreated patients. The Y. pestis 1.ORI3-k single-nucleotide polymorphism genotype might cause larger epidemics. Multidrug-resistant strains and persistence of the pathogen in natural foci near human settlements pose severe risks to populations in plague-endemic regions and require outbreak response strategies.

  1. Investigating the Lithospheric Structure of Southern Madagascar

    NASA Astrophysics Data System (ADS)

    Tilmann, F. J.; Yuan, X.; Rumpker, G.; Heit, B.; Rambolamana, G.; Rindraharisaona, E.; Priestley, K. F.

    2013-12-01

    The island of Madagascar occupies a key region in both the assembly and the multi-stage breakup of Gondwanaland, itself part of the super-continent Pangaea. Madagascar consists of an amalgamation of continental material, with the oldest rocks being of Archaean age. Its ancient fabric is characterised by several shear zones, some of them running oblique to the N-S trend, in particular in the south of the island. More recently during the Neogene, moderate volcanism has occurred in the Central and Northern part of the island, and there are indications of uplift throughout Eastern Madagascar over the last 10 Ma. Although Madagascar is now located within the interior of the African plate and far away from major plate boundaries (> 1000 km from the East African rift system and even further from the Central and South-West Indian Ridges), its seismic activity indicates that some deformation is taking place, and present-day kinematic models based on geodetic data and earthquake moment tensors in the global catalogues identify a diffuse N-S-oriented minor boundary separating two microplates, which appears to pass through Madagascar. In spite of the presence of Archaean and Proterozoic rocks continent-wide scale studies indicate a thin lithosphere (<120 km) throughout Madagascar, but are based on sparse data and cannot resolve the difference between eastern and western Madagascar. We are operating a ENE-WSW oriented linear array of 25 broadband stations in southern Madagascar, extending from coast to coast and sampling the sedimentary basins in the west as well as the metamorphic rocks in the East, cutting geological boundaries seen at the surface at high angle. The array crosses the prominent Bongolava-Ranotsara shear zone which is thought to have been formed during Gondwanaland assembly. The array recorded the magnitude 5.3 earthquake of January 25, 2013 which occurred just off its western edge. In addition, in May 2013 we have deployed 25 short period sensors in the

  2. Late Quaternary stratigraphic charcoal records from Madagascar

    NASA Astrophysics Data System (ADS)

    Burney, David A.

    1987-09-01

    The classic view regarding the cause of the extinction of at least 17 species of large mammals, birds, and reptiles in Madagascar during the late Holocene implicates human use of fire to modify the environment. However, analysis of the charcoal stratigraphy of three sediment cores from Madagascar shows that late Pleistocene and early- to mid-Holocene sediments deposited prior to human settlement often contain more charcoal than postsettlement and modern sediments. This observation, which is confirmed by independent measurements from direct assay and palynological counting techniques, suggests that widely held but previously untested beliefs concerning the importance of anthropogenic fires in late Holocene environmental changes and megafaunal extinctions of Madagascar may be based on an overly simplified version of actual prehistoric conditions. Moderate to low charcoal values characterized only the late Holocene millennia immediately prior to the presumed time of arrival of the first settlers. Human settlement is probably indicated in the stratigraphy by the sharp rise in charcoal content observed beginning ca. 1500 yr B.P. Fire appears to be a significant natural component of prehuman environments in Madagascar, but some factor, probably climate, has modulated the extent of natural burning.

  3. Barriers to Student Success in Madagascar

    ERIC Educational Resources Information Center

    Wills, Abigail R.; Reuter, Kim E.; Gudiel, Arleen A.; Hessert, Bryan P.; Sewall, Brent J.

    2014-01-01

    Various indicators suggest that math and science students in many developing countries are lagging behind their counterparts in other nations. Using Madagascar as a case study, we aimed to: (1) evaluate the effectiveness of education among those enrolled in science and math programs at primary, secondary, and university institutions; and, (2)…

  4. A Way Forward for Healthcare in Madagascar?

    PubMed

    Marks, Florian; Rabehanta, Nathalie; Baker, Stephen; Panzner, Ursula; Park, Se Eun; Fobil, Julius N; Meyer, Christian G; Rakotozandrindrainy, Raphaël

    2016-03-15

    A healthcare utilization survey was conducted as a component of the Typhoid Fever Surveillance in Africa Program (TSAP). The findings of this survey in Madagascar contrasted with those in other sites of the program; namely, only 30% of the population sought healthcare at the government-provided healthcare facilities for fever. These findings promoted us to determine the drivers and barriers in accessing and utilizing healthcare in Madagascar. Here we review the results of the TSAP healthcare utilization initiative and place them in the context of the current organization of the Madagascan healthcare system. Our work highlights the demands of the population for access to appropriate healthcare and the need for novel solutions that can quickly provide an affordable and sustainable basic healthcare infrastructure until a government-funded scheme is in place.

  5. Pneumonic Plague Transmission, Moramanga, Madagascar, 2015

    PubMed Central

    Ramasindrazana, Beza; Andrianaivoarimanana, Voahangy; Rakotondramanga, Jean Marius; Birdsell, Dawn N.; Ratsitorahina, Maherisoa

    2017-01-01

    During a pneumonic plague outbreak in Moramanga, Madagascar, we identified 4 confirmed, 1 presumptive, and 9 suspected plague case-patients. Human-to-human transmission among close contacts was high (reproductive number 1.44) and the case fatality rate was 71%. Phylogenetic analysis showed that the Yersinia pestis isolates belonged to group q3, different from the previous outbreak. PMID:28221119

  6. Madagascar's grasses and grasslands: anthropogenic or natural?

    PubMed Central

    Besnard, Guillaume; Forest, Félix; Malakasi, Panagiota; Moat, Justin; Clayton, W. Derek; Ficinski, Paweł; Savva, George M.; Nanjarisoa, Olinirina P.; Razanatsoa, Jacqueline; Randriatsara, Fetra O.; Kimeu, John M.; Luke, W. R. Quentin; Kayombo, Canisius; Linder, H. Peter

    2016-01-01

    Grasses, by their high productivity even under very low pCO2, their ability to survive repeated burning and to tolerate long dry seasons, have transformed the terrestrial biomes in the Neogene and Quaternary. The expansion of grasslands at the cost of biodiverse forest biomes in Madagascar is often postulated as a consequence of the Holocene settlement of the island by humans. However, we show that the Malagasy grass flora has many indications of being ancient with a long local evolutionary history, much predating the Holocene arrival of humans. First, the level of endemism in the Madagascar grass flora is well above the global average for large islands. Second, a survey of many of the more diverse areas indicates that there is a very high spatial and ecological turnover in the grass flora, indicating a high degree of niche specialization. We also find some evidence that there are both recently disturbed and natural stable grasslands: phylogenetic community assembly indicates that recently severely disturbed grasslands are phylogenetically clustered, whereas more undisturbed grasslands tend to be phylogenetically more evenly distributed. From this evidence, it is likely that grass communities existed in Madagascar long before human arrival and so were determined by climate, natural grazing and other natural factors. Humans introduced zebu cattle farming and increased fire frequency, and may have triggered an expansion of the grasslands. Grasses probably played the same role in the modification of the Malagasy environments as elsewhere in the tropics. PMID:26791612

  7. Madagascar's grasses and grasslands: anthropogenic or natural?

    PubMed

    Vorontsova, Maria S; Besnard, Guillaume; Forest, Félix; Malakasi, Panagiota; Moat, Justin; Clayton, W Derek; Ficinski, Paweł; Savva, George M; Nanjarisoa, Olinirina P; Razanatsoa, Jacqueline; Randriatsara, Fetra O; Kimeu, John M; Luke, W R Quentin; Kayombo, Canisius; Linder, H Peter

    2016-01-27

    Grasses, by their high productivity even under very low pCO2, their ability to survive repeated burning and to tolerate long dry seasons, have transformed the terrestrial biomes in the Neogene and Quaternary. The expansion of grasslands at the cost of biodiverse forest biomes in Madagascar is often postulated as a consequence of the Holocene settlement of the island by humans. However, we show that the Malagasy grass flora has many indications of being ancient with a long local evolutionary history, much predating the Holocene arrival of humans. First, the level of endemism in the Madagascar grass flora is well above the global average for large islands. Second, a survey of many of the more diverse areas indicates that there is a very high spatial and ecological turnover in the grass flora, indicating a high degree of niche specialization. We also find some evidence that there are both recently disturbed and natural stable grasslands: phylogenetic community assembly indicates that recently severely disturbed grasslands are phylogenetically clustered, whereas more undisturbed grasslands tend to be phylogenetically more evenly distributed. From this evidence, it is likely that grass communities existed in Madagascar long before human arrival and so were determined by climate, natural grazing and other natural factors. Humans introduced zebu cattle farming and increased fire frequency, and may have triggered an expansion of the grasslands. Grasses probably played the same role in the modification of the Malagasy environments as elsewhere in the tropics. © 2016 The Authors.

  8. Captive Conditions of Pet Lemurs in Madagascar.

    PubMed

    Reuter, Kim E; Schaefer, Melissa S

    2016-01-01

    Live extraction of wildlife is a threat to biodiversity and can compromise animal welfare standards. Studies of the captive environments and welfare of pet primates are known, but none has focused on Madagascar. We aimed to expand knowledge about the captive conditions of pet lemurs in Madagascar. We hypothesized that captive lemurs would often be kept in restrictive settings, including small cages, would be fed foods inconsistent with their natural diets and, as a result, would be in bad physical or psychological health. Data were collected via a web-based survey (n = 253 reports) and from the websites and social media pages of 25 hotels. Most lemurs seen by respondents were either kept on a rope/leash/chain or in a cage (67%), though some lemurs were habituated and were not restrained (28%). Most of the time (72%) cages were considered small, and lemurs were rarely kept in captivity together with other lemurs (81% of lemurs were caged alone). Pet lemurs were often fed foods inconsistent with their natural diets, and most (53%) were described as being in bad health. These findings point to a need to undertake outreach to pet lemur owners in Madagascar about the captivity requirements of primates.

  9. Investigating the Lithospheric Structure of Southern Madagascar

    NASA Astrophysics Data System (ADS)

    Tilmann, Frederik; Yuan, Xiaohui; Rümpker, Georg; Gerard, Rambolamana; Elisa, Rindraharisaona; Priestley, Keith

    2014-05-01

    The island of Madagascar occupies a key region in both the assembly and the multi-stage breakup of Gondwanaland, itself part of the super-continent Pangaea. Madagascar consists of an amalgamation of continental material, with the oldest rocks being of Archaean age. Its ancient fabric is characterised by several shear zones, some of them running oblique to the N-S trend, in particular in the south of the island. More recently during the Neogene, moderate volcanism has occurred in the Central and Northern part of the island, and there are indications of uplift throughout Eastern Madagascar over the last 10 Ma. Although Madagascar is now located within the interior of the African plate and far away from major plate boundaries (> 1000 km from the East African rift system and even further from the Central and South-West Indian Ridges), its seismic activity indicates that some deformation is taking place, and present-day kinematic models based on geodetic data and earthquake moment tensors in the global catalogues identify a diffuse N-S-oriented minor boundary separating two microplates, which appears to pass through Madagascar. In spite of the presence of Archaean and Proterozoic rocks continent-wide scale studies indicate a thin lithosphere (<120 km) throughout Madagascar, but are based on sparse data. We are operating a ENE-WSW oriented linear array of 25 broadband stations in southern Madagascar, extending from coast to coast and sampling the sedimentary basins in the west as well as the metamorphic rocks in the East, cutting geological boundaries seen at the surface at high angle. The array crosses the prominent Bongolava-Ranotsara shear zone which is thought to have been formed during Gondwanaland assembly, although this interpretation has recently been questioned. The array recorded the magnitude 5.3 earthquake of January 25, 2013 which occurred just off its western edge. In addition, in May 2013 we have deployed 25 short period sensors in the eastern part of the

  10. Development of Environmental Education Programs for Protected Areas in Madagascar

    ERIC Educational Resources Information Center

    Ormsby, Alison

    2007-01-01

    Environmental education programs for schools in the peripheral zone of protected areas in Madagascar are still needed in numerous locations. My research investigated the status of environmental education and communication (EE&C) programs at Masoala National Park, Madagascar, as well as the attitudes of local residents toward the park and park…

  11. Development of Environmental Education Programs for Protected Areas in Madagascar

    ERIC Educational Resources Information Center

    Ormsby, Alison

    2007-01-01

    Environmental education programs for schools in the peripheral zone of protected areas in Madagascar are still needed in numerous locations. My research investigated the status of environmental education and communication (EE&C) programs at Masoala National Park, Madagascar, as well as the attitudes of local residents toward the park and park…

  12. [A case of pulmonary multiresistant Mycobacterium bovis tuberculosis in Madagascar].

    PubMed

    Ramarokoto, H; Andrianasolo, D; Rasolonavalona, T; Ramaroson, F; Razafitsiarovana, I; Vincent, V; Ratsimba, L; Rasolofo Razanamparany, V

    2003-01-01

    We report a chronic case of pulmonary tuberculosis in a Malagasy citizen from Antsohihy (West of Madagascar), who was infected with a multi-drug resistant Mycobacterium bovis strain. This is the first case reported of the isolation of such a strain in Madagascar.

  13. An abelisauroid theropod dinosaur from the Turonian of Madagascar.

    PubMed

    Farke, Andrew A; Sertich, Joseph J W

    2013-01-01

    Geophysical evidence strongly supports the complete isolation of India and Madagascar (Indo-Madagascar) by ∼100 million years ago, though sparse terrestrial fossil records from these regions prior to ∼70 million years ago have limited insights into their biogeographic history during the Cretaceous. A new theropod dinosaur, Dahalokely tokana, from Turonian-aged (∼90 million years old) strata of northernmost Madagascar is represented by a partial axial column. Autapomorphies include a prominently convex prezygoepipophyseal lamina on cervical vertebrae and a divided infraprezygapophyseal fossa through the mid-dorsal region, among others. Phylogenetic analysis definitively recovers the species as an abelisauroid theropod and weakly as a noasaurid. Dahalokely is the only known dinosaur from the interval during which Indo-Madagascar likely existed as a distinct landmass, but more complete material is needed to evaluate whether or not it is more closely related to later abelisauroids of Indo-Madagascar or those known elsewhere in Gondwana.

  14. Economie et enseignement a Madagascar. (Economy and Education in Madagascar.) Financement des systemes educatifs: etudes de cas Nationales 8.

    ERIC Educational Resources Information Center

    Hugon, Philippe

    The purpose of this volume is to analyze the problems of school finance in Madagascar, including those that have arisen in the past decade and those anticipated in the present decade (through 1980). More generally, this book examines past and future connections between the economic and educational systems in Madagascar. The author examines the…

  15. Evolution of Neogene Dynamic Topography in Madagascar

    NASA Astrophysics Data System (ADS)

    Paul, J. D.; Roberts, G.; White, N. J.

    2012-12-01

    Madagascar is located on the fringes of the African superswell. Its position and the existence of a +30 mGal long wavelength free-air gravity anomaly suggest that its present-day topography is maintained by convective circulation of the sub-lithospheric mantle. Residual depth anomalies of oceanic crust encompassing the island imply that Madagascar straddles a dynamic topographic gradient. In June-July 2012, we examined geologic evidence for Neogene uplift around the Malagasy coastline. Uplifted coral reef deposits, fossil beach rock, and terraces demonstrate that the northern and southern coasts are probably being uplifted at a rate of ~0.2 mm/yr. Rates of uplift clearly vary around the coastline. Inland, extensive peneplains occur at elevations of 1 - 2 km. These peneplains are underlain by 10 - 20 m thick laterite deposits, and there is abundant evidence for rapid erosion (e.g. lavaka). Basaltic volcanism also occurred during Neogene times. These field observations can be combined with an analysis of drainage networks to determine the spatial and temporal pattern of convectively driven uplift. ~100 longitudinal river profiles were extracted from a digital elevation model of Madagascar. An inverse model is then used to minimize the misfit between observed and calculated river profiles as a function of uplift rate history. During inversion, the residual misfit decreases from ~20 to ~4. Our results suggest that youthful and rapid uplift of 1-2 km occurred at rates of 0.2-0.4 mm/yr during the last ˜15 Myr. The algorithm resolves distinct phases of uplift which generate localized swells of high topography and relief (e.g. the Hauts Plateaux). Our field observations and modeling indicate that the evolution of drainage networks may contain useful information about mantle convective processes.

  16. Tungiasis Outbreak in Travelers From Madagascar.

    PubMed

    Belaz, Sorya; Gay, Eugénie; Robert-Gangneux, Florence; Beaucournu, Jean-Claude; Guiguen, Claude

    2015-01-01

    Seven patients from a group of 16 travelers were diagnosed at our institution with one or more sand fleas on their toes, 1 day to 3 weeks after returning from Madagascar. A questionnaire was sent to the whole group to collect clinical and epidemiological information, which showed that 9 of 13 (69%) had received pre-travel medical advice, but none were aware of sand flea; thus prevention measures were rarely applied. Five of seven (71%) patients wore open sandals throughout the trip. Overall, 10 sand fleas were extracted.

  17. Mammalian biodiversity on Madagascar controlled by ocean currents.

    PubMed

    Ali, Jason R; Huber, Matthew

    2010-02-04

    Madagascar hosts one of the world's most unusual, endemic, diverse and threatened concentrations of fauna. To explain its unique, imbalanced biological diversity, G. G. Simpson proposed the 'sweepstakes hypothesis', according to which the ancestors of Madagascar's present-day mammal stock rafted there from Africa. This is an important hypothesis in biogeography and evolutionary theory for how animals colonize new frontiers, but its validity is questioned. Studies suggest that currents were inconsistent with rafting to Madagascar and that land bridges provided the migrants' passage. Here we show that currents could have transported the animals to the island and highlight evidence inconsistent with the land-bridge hypothesis. Using palaeogeographic reconstructions and palaeo-oceanographic modelling, we find that strong surface currents flowed from northeast Mozambique and Tanzania eastward towards Madagascar during the Palaeogene period, exactly as required by the 'sweepstakes process'. Subsequently, Madagascar advanced north towards the equatorial gyre and the regional current system evolved into its modern configuration with flows westward from Madagascar to Africa. This may explain why no fully non-aquatic land mammals have colonized Madagascar since the arrival of the rodents and carnivorans during the early-Miocene epoch. One implication is that rafting may be the dominant means of overseas dispersal in the Cenozoic era when palaeocurrent directions are properly considered.

  18. The Seismic Structure of the Crust of Madagascar

    NASA Astrophysics Data System (ADS)

    Wysession, M. E.; Andriampenomanana Ny Ony, F. S. T.; Tsiriandrimanana, R.; Pratt, M. J.; Aleqabi, G. I.; Wiens, D. A.; Nyblade, A.; Shore, P.; Rambolamanana, G.; Tilmann, F. J.

    2015-12-01

    The structure of Madagascar's crust is determined using both body wave receiver functions as well as an analysis of surface waves using ambient-noise and two-plane-wave earthquake surface waves analyses. The primary data used are from the 2011-2013 MACOMO (Madagascar, the Comoros, and Mozambique) broadband seismic array from the PASSCAL program of IRIS (Incorporated Research Institutions for Seismology), funded by the NSF. Additional data came from the RHUM-RUM project (led by G. Barruol and K. Sigloch), the Madagascar Seismic Profile (led by F. Tilmann), and the GSN. The crustal structure of Madagascar, which had previously only been inferred from a gravity survey assuming isostasy, shows a strong correlation with its tectonic history. Crustal thicknesses are greatest, reaching 45 km, along the spine of Madagascar's mountains, which run north-south across the island. Crustal thicknesses thin to the east and west, which are both regions of tectonic separation, however, with very different results. Extensive crustal thinning occurred along the western coasts of Madagascar when the island rifted away from mainland Africa beginning 160 Ma ago. The crust is as thin as 20 km here, but the thickness of basin sediments is as great as 9 km, with the crystalline basement continental crust thinning to 12 km at its thinnest. Along the east coast, the crustal thickness is within the 33-38 km range, but it is thickest in the two places where mesoarchaean crust was rifted off from the Indian subcontinent when it broke away from Madagascar. Surface wave studies show that velocities beneath Madagascar are generally slow, when compared to global models such as AK135. This appears to be due to the occurrence of Cenozoic intraplate volcanism in three regions of Madagascar (north, central, and southwest), each of which has strong underlying seismic low-velocity anomalies in the lithospheric mantle and asthenosphere.

  19. Allergenicity of the Madagascar hissing cockroach.

    PubMed

    Morgan, Marjorie S; Arlian, Larry G; Bernstein, Jonathan A; Yoder, Jay A

    2007-03-01

    The Madagascar hissing cockroach (Gromphadorhina portentosa) has become popular as a pet and as an educational tool in classrooms, zoos, and museums. To determine whether proteins in G. portentosa are allergens and whether these allergens cross-react with those of other cockroach species. Sera from cockroach-sensitive individuals and control subjects were used to probe immunoblots for the presence of circulating IgE that bound to proteins present in extracts of 4 cockroach species. Serum from an individual sensitized to G portentosa had circulating IgE that bound to proteins in extracts of all 4 cockroach species. Eight of 15 Blatella germanica-sensitized patients had IgE that bound to proteins in extracts prepared from G portentosa. Rabbit antiserum to Periplaneta americana and to Bla g 1 also contained antibody that bound to proteins in G. portentosa extract, demonstrating antigenic cross-reactivity among these cockroach species. Allergists, teachers, parents, and patients should be aware that sensitization and allergic reactions to the Madagascar hissing cockroach can occur. Caution should be taken if these exotic cockroaches are used in educational exercises in schools, museums, and zoos to protect predisposed individuals.

  20. The Madagascar Bloom - a serendipitous study

    NASA Astrophysics Data System (ADS)

    Srokosz, M. A.; Quartly, G.

    2012-12-01

    The late austral summer (February-April) phytoplankton bloom that occurs east of Madagascar, exhibits significant interannual variability and at its largest extent covers ~1% of the world's ocean surface area. The bloom raises many intriguing questions about how it begins, is sustained, propagates to the east, exports carbon and ends. It has been observed and studied using satellite ocean colour observations, but the lack of in situ data makes it difficult to address these questions. Here we describe observations that were made on a cruise in February 2005 serendipitously. These show clearly for the first time the existence of both a deep chlorophyll maximum at ~70-110m depths (seen in SeaSoar fluorimeter data) and a surface chlorophyll signature (seen in SeaWiFS satellite ocean colour data). The observations also show the modulation of biological signature at the surface by the eddy field, but not apparently of the deep chlorophyll maximum. In situ observations indicate that Trichodesmium dominates the bloom nearer to Madagascar, while the diatom Rhizosolenia clevei (and its symbiont Richelia intracellularis) dominates further from the island. In addition, SeaSoar Optical Plankton Counter (OPC), temperature and salinity data suggest that the surface bloom seen in the SeaWiFS data is confined to the shallow (~30m) mixed layer. It is hypothesised that the interannual variability in bloom intensity may be due to variations in coastal upwelling and thus the supply of iron, which is a micronutrient that can limit diazotroph growth.

  1. The Madagascar Bloom: A serendipitous study

    NASA Astrophysics Data System (ADS)

    Srokosz, M. A.; Quartly, G. D.

    2013-01-01

    The late austral summer (February-April) phytoplankton bloom that occurs east of Madagascar exhibits significant interannual variability and at its largest extent covers ~1% of the world's ocean surface area. The bloom raises many intriguing questions about how it begins, is sustained, propagates to the east, exports carbon, and ends. It has been observed and studied using satellite ocean color observations, but the lack of in situ data makes it difficult to address these questions. Here we describe observations that were made serendipitously on a cruise in February 2005. These show clearly for the first time the simultaneous existence of a deep chlorophyll maximum at ~70-110 m depths (seen in SeaSoar fluorimeter data) and a surface chlorophyll signature [seen in Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite ocean color data]. The observations also show the modulation of the biological signature at the surface by the eddy field but not of the deep chlorophyll maximum. Trichodesmium dominates the bloom nearer to Madagascar, while the diatom Rhizosolenia clevei (and its symbiont Richelia intracellularis) dominates further from the island. The surface bloom seen in the SeaWiFS data is confined to the shallow (~30 m) mixed layer. It is hypothesized that the interannual variability in bloom intensity may be due to variations in coastal upwelling and thus the supply of iron, which is a micronutrient that can limit diazotroph growth.

  2. A small cohort of Island Southeast Asian women founded Madagascar

    PubMed Central

    Cox, Murray P.; Nelson, Michael G.; Tumonggor, Meryanne K.; Ricaut, François-X.; Sudoyo, Herawati

    2012-01-01

    The settlement of Madagascar is one of the most unusual, and least understood, episodes in human prehistory. Madagascar was one of the last landmasses to be reached by people, and despite the island's location just off the east coast of Africa, evidence from genetics, language and culture all attests that it was settled jointly by Africans, and more surprisingly, Indonesians. Nevertheless, extremely little is known about the settlement process itself. Here, we report broad geographical screening of Malagasy and Indonesian genetic variation, from which we infer a statistically robust coalescent model of the island's initial settlement. Maximum-likelihood estimates favour a scenario in which Madagascar was settled approximately 1200 years ago by a very small group of women (approx. 30), most of Indonesian descent (approx. 93%). This highly restricted founding population raises the possibility that Madagascar was settled not as a large-scale planned colonization event from Indonesia, but rather through a small, perhaps even unintended, transoceanic crossing. PMID:22438500

  3. A small cohort of Island Southeast Asian women founded Madagascar.

    PubMed

    Cox, Murray P; Nelson, Michael G; Tumonggor, Meryanne K; Ricaut, François-X; Sudoyo, Herawati

    2012-07-22

    The settlement of Madagascar is one of the most unusual, and least understood, episodes in human prehistory. Madagascar was one of the last landmasses to be reached by people, and despite the island's location just off the east coast of Africa, evidence from genetics, language and culture all attests that it was settled jointly by Africans, and more surprisingly, Indonesians. Nevertheless, extremely little is known about the settlement process itself. Here, we report broad geographical screening of Malagasy and Indonesian genetic variation, from which we infer a statistically robust coalescent model of the island's initial settlement. Maximum-likelihood estimates favour a scenario in which Madagascar was settled approximately 1200 years ago by a very small group of women (approx. 30), most of Indonesian descent (approx. 93%). This highly restricted founding population raises the possibility that Madagascar was settled not as a large-scale planned colonization event from Indonesia, but rather through a small, perhaps even unintended, transoceanic crossing.

  4. A New Genus of Macropsinae (Hemiptera: Cicadellidae) From Madagascar

    PubMed Central

    Yang, Liyuan; Dietrich, C.H.; Zhang, Yalin

    2016-01-01

    Paragalboa acuta gen. & sp. n. is described and illustrated from Madagascar. The new genus shows morphological affinities to the Macropsini genus Galboa Distant recorded from Seychelles. A checklist of all known genera of Macropsinae is provided. PMID:27389563

  5. Anisotropic Lithospheric Structure of Southern Madagascar from Ambient Seismic Noise

    NASA Astrophysics Data System (ADS)

    Dreiling, J.; Tilmann, F. J.; Yuan, X.; Rumpker, G.

    2016-12-01

    The island of Madagascar occupied a key region in both the assembly and the multi-stage breakup of Gondwana. Madagascar consists of amalgamated continental material comprising several distinct tectonic units. Because of its key role in the assembly of Gondwana, numerous geological and geophysical investigations have been carried out in Madagascar to understand the evolution of Gondwana.The aim of this study is to characterize the lithospheric structure of Southern Madagascar using ambient seismic noise correlation. Radial anisotropy is determined to learn about the crust/mantle deformation around the central Southern Madagascan shear zones (i.e. the Ampanihy, Beraketa and Ranotsara shear zones) and to shed light on the geological development of Madagascar and its role during the breakup of Gondwana. In the analysis we included seismic data from the SELASOMA project in Southern Madagascar, which is a passive seismic experiment carried out by the GFZ German Research Centre for Geosciences from May 2012 to May 2014. Seismic data recorded by 61 three-component seismometers were pre-processed and cross-correlated. Group velocity dispersion curves were picked manually for the vertical-vertical and transverse-transverse component correlations, which represent the Rayleigh (ZZ) and Love (TT) surface waves, respectively. Velocities from periods between 0.7 and 20 seconds are used for tomography and computation of radial anisotropy of the lithosphere.

  6. Two new Pediopsis species and a new Ruandopsis species (Hemiptera: Cicadellidae: Macropsinae) from Madagascar.

    PubMed

    Yang, Liyuan; Dietrich, Christopher H; Zhang, Yalin

    2016-10-04

    Three new species, Pediopsis tripartita, P. subtilis and Ruandopsis elongata spp. nov., from Madagascar are described. These species represent the first records of their respective genera in Madagascar. Images of adults and genitalia of the three species are provided.

  7. Imperfect isolation: factors and filters shaping Madagascar's extant vertebrate fauna.

    PubMed

    Samonds, Karen E; Godfrey, Laurie R; Ali, Jason R; Goodman, Steven M; Vences, Miguel; Sutherland, Michael R; Irwin, Mitchell T; Krause, David W

    2013-01-01

    Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascar's colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the island's biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the island's paleogeographical evolution to determine how particular events influenced the arrival of the island's extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascar's tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the island's isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascar's extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascar's unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of other, more

  8. Deforestation and plant diversity of Madagascar's littoral forests.

    PubMed

    Consiglio, Trisha; Schatz, George E; McPherson, Gordon; Lowry, Porter P; Rabenantoandro, Johny; Rogers, Zachary S; Rabevohitra, Raymond; Rabehevitra, David

    2006-12-01

    Few studies have attempted to quantify the reduction or document the floristic composition of forests in Madagascar. Thus, we focused specifically on deforestation and plant diversity in Madagascar's eastern littoral community. We used a data set of approximately 13,500 specimen records compiled from both historical and contemporary collections resulting from recent intensive inventory efforts to enumerate total plant species richness and to analyze the degree of endemism within littoral forests. Change in littoral forest cover from original to current extent was estimated using geographical information systems tools, remote sensing data (satellite imagery and low-elevation digital photography), and environmental data layers. Of the original littoral forest only 10.3% remains in the form of small forest parcels, and only 1.5% of these remaining fragments are included within the existing protected-areas network. Additionally, approximately 13% of Madagascar's total native flora has been recorded from these forests that originally occupied <1% of its total land surface, and over 25% of the 1535 plant species known from littoral forests are endemic to this community. Given the ongoing pressure from human settlement along Madagascar's eastern coast, protection of the remaining forest fragments is critical for their survival. Fifteen of the largest intact littoral forest fragments we identified, collectively representing 41.5% of remaining littoral forest, are among priority sites recommended to the government of Madagascar for plant conservation and incorporation into the protected-areas network.

  9. Market structures, socioeconomics, and tobacco usage patterns in Madagascar.

    PubMed

    Blecher, Evan; Liber, Alex C; Chaussard, Martine; Fedewa, Stacey

    2014-01-01

    The isolated island nation of Madagascar has substantial prevalence of both smoking and smokeless tobacco use, although not of dual use. Madagascar's tobacco market, much like its historical and cultural underpinnings, appears to have both Asian and African influences. Additionally, it has a unique market structure that plays an important role in influencing patterns of tobacco use. This study analyzes the determinants of smoking and smokeless tobacco use in Madagascar. We used the 2008 Madagascar Demographic and Health Survey to analyze both smoking tobacco and smokeless tobacco use, stratified by gender. Multivariate log binomial models were used to evaluate the relationship between tobacco use and age, residence (urban/rural), province, marital status, and education. Our analysis indicates that two distinctly different groups of people use two distinctly different tobacco products. Smoking is almost exclusively used by men and does not appear to be related to socioeconomic status. Conversely, smokeless tobacco is consumed by large proportions of both men and women, who are less educated and live in rural areas of the country. This disparate pattern in consumption is a reflection of the different market structures for smokeless tobacco (a cottage industry) and smoking tobacco (a near monopoly). Distinct market-based, geographic, and socioeconomic disparities in tobacco use are explored in order to begin the classification of Madagascar's tobacco epidemic as more African, more Asian, or as a distinctly different environment.

  10. Influenza seasonality in Madagascar: the mysterious African free-runner.

    PubMed

    Alonso, Wladimir Jimenez; Guillebaud, Julia; Viboud, Cecile; Razanajatovo, Norosoa Harline; Orelle, Arnaud; Zhou, Steven Zhixiang; Randrianasolo, Laurence; Heraud, Jean-Michel

    2015-05-01

    The seasonal drivers of influenza activity remain debated in tropical settings where epidemics are not clearly phased. Antananarivo is a particularly interesting case study because it is in Madagascar, an island situated in the tropics and with quantifiable connectivity levels to other countries. We aimed at disentangling the role of environmental forcing and population fluxes on influenza seasonality in Madagascar. We compiled weekly counts of laboratory-confirmed influenza-positive specimens for the period 2002 to 2012 collected in Antananarivo, with data available from sub-Saharan countries and countries contributing most foreign travelers to Madagascar. Daily climate indicators were compiled for the study period. Overall, influenza activity detected in Antananarivo predated that identified in temperate Northern Hemisphere locations. This activity presented poor temporal matching with viral activity in other countries from the African continent or countries highly connected to Madagascar excepted for A(H1N1)pdm09. Influenza detection in Antananarivo was not associated with travel activity and, although it was positively correlated with all climatic variables studied, such association was weak. The timing of influenza activity in Antananarivo is irregular, is not driven by climate, and does not align with that of countries in geographic proximity or highly connected to Madagascar. This work opens fresh questions regarding the drivers of influenza seasonality globally particularly in mid-latitude and less-connected regions to tailor vaccine strategies locally. © 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  11. Influenza seasonality in Madagascar: the mysterious African free-runner

    PubMed Central

    Alonso, Wladimir Jimenez; Guillebaud, Julia; Viboud, Cecile; Razanajatovo, Norosoa Harline; Orelle, Arnaud; Zhou, Steven Zhixiang; Randrianasolo, Laurence; Heraud, Jean-Michel

    2015-01-01

    Background The seasonal drivers of influenza activity remain debated in tropical settings where epidemics are not clearly phased. Antananarivo is a particularly interesting case study because it is in Madagascar, an island situated in the tropics and with quantifiable connectivity levels to other countries. Objectives We aimed at disentangling the role of environmental forcing and population fluxes on influenza seasonality in Madagascar. Methods We compiled weekly counts of laboratory-confirmed influenza-positive specimens for the period 2002 to 2012 collected in Antananarivo, with data available from sub-Saharan countries and countries contributing most foreign travelers to Madagascar. Daily climate indicators were compiled for the study period. Results Overall, influenza activity detected in Antananarivo predated that identified in temperate Northern Hemisphere locations. This activity presented poor temporal matching with viral activity in other countries from the African continent or countries highly connected to Madagascar excepted for A(H1N1)pdm09. Influenza detection in Antananarivo was not associated with travel activity and, although it was positively correlated with all climatic variables studied, such association was weak. Conclusions The timing of influenza activity in Antananarivo is irregular, is not driven by climate, and does not align with that of countries in geographic proximity or highly connected to Madagascar. This work opens fresh questions regarding the drivers of influenza seasonality globally particularly in mid-latitude and less-connected regions to tailor vaccine strategies locally. PMID:25711873

  12. Sterols from the Madagascar Sponge Fascaplysinopsis sp

    PubMed Central

    Aknin, Maurice; Gros, Emmanuelle; Vacelet, Jean; Kashman, Yoel; Gauvin-Bialecki, Anne

    2010-01-01

    The sponge Fascaplysinopsis sp. (order Dictyoceratida, Family Thorectidae) from the west coast of Madagascar (Indian Ocean) is a particularly rich source of bioactive nitrogenous macrolides. The previous studies on this organism led to the suggestion that the latter should originate from associated microsymbionts. In order to evaluate the influence of microsymbionts on lipid content, 10 samples of Fascaplysinopsis sp. were investigated for their sterol composition. Contrary to the secondary metabolites, the sterol patterns established were qualitatively and quantitatively stable: 14 sterols with different unsaturated nuclei, Δ5, Δ7 and Δ5,7, were identified; the last ones being the main sterols of the investigated sponges. The chemotaxonomic significance of these results for the order Dictyoceratida is also discussed in the context of the literature. The conjugated diene system in Δ5,7 sterols is known to be unstable and easily photo-oxidized during storage and/or experiments to produce 5α,8α-epidioxy sterols. However, in this study, no 5α,8α-epidioxysterols (or only trace amounts) were observed. Thus, it was supposed that photo-oxidation was avoided thanks to the natural antioxidants detected in Fascaplysinopsis sp. by both the DPPH and β-caroten bleaching assays. PMID:21339959

  13. Sterols from the Madagascar sponge Fascaplysinopsis sp.

    PubMed

    Aknin, Maurice; Gros, Emmanuelle; Vacelet, Jean; Kashman, Yoel; Gauvin-Bialecki, Anne

    2010-12-17

    The sponge Fascaplysinopsis sp. (order Dictyoceratida, Family Thorectidae) from the west coast of Madagascar (Indian Ocean) is a particularly rich source of bioactive nitrogenous macrolides. The previous studies on this organism led to the suggestion that the latter should originate from associated microsymbionts. In order to evaluate the influence of microsymbionts on lipid content, 10 samples of Fascaplysinopsis sp. were investigated for their sterol composition. Contrary to the secondary metabolites, the sterol patterns established were qualitatively and quantitatively stable: 14 sterols with different unsaturated nuclei, Δ(5), Δ(7) and Δ(5,7), were identified; the last ones being the main sterols of the investigated sponges. The chemotaxonomic significance of these results for the order Dictyoceratida is also discussed in the context of the literature. The conjugated diene system in Δ(5,7) sterols is known to be unstable and easily photo-oxidized during storage and/or experiments to produce 5α,8α-epidioxy sterols. However, in this study, no 5α,8α-epidioxysterols (or only trace amounts) were observed. Thus, it was supposed that photo-oxidation was avoided thanks to the natural antioxidants detected in Fascaplysinopsis sp. by both the DPPH and β-caroten bleaching assays.

  14. Gully erosion in Madagascar: causes and impacts

    NASA Astrophysics Data System (ADS)

    Raveloson, Andrea; Székely, Balázs; Visnovitz, Ferenc

    2017-04-01

    Soil erosion has been recognized as the main cause of land degradation worldwide and gully erosion is currently considered as one of the most impressive and striking erosion type. This global environmental problem has numerous causes (both natural and anthropogenic) and inflict serious socio-economic problems all around the world. The present study aims to discuss the occurrence and environmental issues related to lavakization in Madagascar and its impact on landscape (badland formation), land use management, flora and fauna, infrastructures, soil properties and human life itself. We assembled and reviewed lavaka researches since 1953. Exact location of the field surveys, cited triggering factors and results of these scientific papers have been studied in detail and compared with our data collected using satellite imagery. Lavaka distribution was analyzed using GIS methods and the relation between their density and different factors was studied. An overview of the many contributing factors (climate, topography, geology, vegetation cover, fault systems, tectonism and land use including inappropriate cultivation and irrigation systems) is given in order to better understand lavaka formation, distribution and impacts. Synthesis of previous researches might help us define area susceptible to gully formation. This can be used to determine prevention priorities for farmers, to manage their lands sustainably. This is ILARG contribution 18.

  15. Malagasy dialects and the peopling of Madagascar

    PubMed Central

    Serva, Maurizio; Petroni, Filippo; Volchenkov, Dima; Wichmann, Søren

    2012-01-01

    The origin of Malagasy DNA is half African and half Indonesian, nevertheless the Malagasy language, spoken by the entire population, belongs to the Austronesian family. The language most closely related to Malagasy is Maanyan (Greater Barito East group of the Austronesian family), but related languages are also in Sulawesi, Malaysia and Sumatra. For this reason, and because Maanyan is spoken by a population which lives along the Barito river in Kalimantan and which does not possess the necessary skill for long maritime navigation, the ethnic composition of the Indonesian colonizers is still unclear. There is a general consensus that Indonesian sailors reached Madagascar by a maritime trek, but the time, the path and the landing area of the first colonization are all disputed. In this research, we try to answer these problems together with other ones, such as the historical configuration of Malagasy dialects, by types of analysis related to lexicostatistics and glottochronology that draw upon the automated method recently proposed by the authors. The data were collected by the first author at the beginning of 2010 with the invaluable help of Joselinà Soafara Néré and consist of Swadesh lists of 200 items for 23 dialects covering all areas of the island. PMID:21632612

  16. [Drug prescriptions: Adherence and understanding in Madagascar].

    PubMed

    Raharinjatovo, L; Ralandison, S

    2015-01-01

    Frequently ignored or neglected, poor adherence is an important cause of treatment failure and a major public health problem. We assessed the factors involved in adherence in a hospital in Madagascar. This long-term study evaluated two groups of variables: patients' level of understanding of their disease and drug prescriptions, and the information on the prescription written by the doctor. We interviewed 93 in-patients (mean age: 50 years) and found that 16% were illiterate. Overall, 27% did not know the name of their illness, 34% were unaware of the treatment objectives, and 14% did not understand the drug prescription. On 20% of the prescriptions, the patients' name was not included, and the daily dose information and schedule was omitted from 16%. A day after receiving the prescription, only 64% had purchased the medication and only 53% of all patients had taken any. A correlation was observed between illiteracy, knowledge of the disease/treatment goals, and non-purchase of drugs. The poor quality of information contained in the prescriptions and patients' poor understanding of what they were supposed to do are obvious. Using pre-completed health forms and text messages might improve adherence.

  17. Understanding the persistence of plague foci in Madagascar.

    PubMed

    Andrianaivoarimanana, Voahangy; Kreppel, Katharina; Elissa, Nohal; Duplantier, Jean-Marc; Carniel, Elisabeth; Rajerison, Minoarisoa; Jambou, Ronan

    2013-11-01

    Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar.

  18. δ(13)C values of some succulent plants from Madagascar.

    PubMed

    Winter, Klaus

    1979-01-01

    δ(13)C values were determined in 20 succulents from Madagascar. The values were indicative of Crassulacean Acid Metabolism in 10 species of the Didiereaceae, 4 species of the Euphorbiaceae, 2 species of the Crassulaceae and 1 species of the Cucurbitaceae. The Didiereaceae and Euphorbiaceae studied are major components of a high biomass xerophytic flora in the semi-arid southwest and south of Madagascar. Three species of the Euphorbiaceae with succulent stems and non-succulent leaves, which were cultivated outdoors in the Tananarive Botanic Garden, showed C3 like δ(13)C values for both leaves and stems. δ(13)C values of leaf and stem material from a similar species, collected in the south of Madagascar, indicated Crassulacean Acid Metabolism.

  19. Understanding the Persistence of Plague Foci in Madagascar

    PubMed Central

    Andrianaivoarimanana, Voahangy; Kreppel, Katharina; Elissa, Nohal; Duplantier, Jean-Marc; Carniel, Elisabeth; Rajerison, Minoarisoa; Jambou, Ronan

    2013-01-01

    Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar. PMID:24244760

  20. First observational evidence of a North Madagascar Undercurrent

    NASA Astrophysics Data System (ADS)

    Ponsoni, Leandro; Aguiar-González, Borja; Nauw, Janine J.; Ridderinkhof, Herman; Maas, Leo R. M.

    2015-12-01

    In situ observations reveal a southeastward-directed North Madagascar Undercurrent (NMUC) below and opposite to the equatorward-directed North Madagascar Current (NMC) off Cape Amber, at the northern tip of Madagascar. Results show an undercurrent hugging the continental slope with its core at 460 m depth and velocities over 0.7 m s-1. Its volume transport is estimated to be 3.1-3.8 Sv, depending on the velocity extrapolation methods used to fill in the data gaps near the slope (no-slip and full-slip, respectively). The thermohaline characteristics show a saltier and warmer NMUC, compared to the surrounding offshore waters, transporting mainly South Indian Central Water. Also, strong horizontal gradients of density are found in the NMUC domain. An inshore cell of coastal downwelling due to Ekman Transport toward the coast is identified, which can explain, at least in part, the strong baroclinic pressure gradients as well as the NMUC development and possible persistence.

  1. Cretaceous may hold promise in Majunga basin, Madagascar

    SciTech Connect

    Lalaharisaina, J.V. ); Ferrand, N.J. )

    1994-08-01

    Recent drilling in the Majunga basin of northwestern Madagascar revealed unexpected light oil shows in excellent quality reservoir sands of Mid-Cretaceous age. Regional reconstructions show the development of a prograding clastic shelf from the Aptian until the Mid-Turonian that extended laterally from the northwest costs of Madagascar into Northwest India and Southeast Pakistan. Six untested play concepts have been identified in Cretaceous reservoirs of the Majunga basin. These plays offer multiple objectives in the depth range of 800--2,500 m within a well defined area. Further untested plays exist for Tertiary and Dogger objectives. The paper describes the geologic setting, exploration history the Cretaceous reservoirs, source rocks, and other potential plays. Political changes in Madagascar the last four years have led to an open door policy for foreign investment. Favorable terms are on offer for investment in the petroleum sector, and high potential exists for development on this island continent.

  2. Rift Valley fever during rainy seasons, Madagascar, 2008 and 2009.

    PubMed

    Andriamandimby, Soa Fy; Randrianarivo-Solofoniaina, Armand Eugène; Jeanmaire, Elisabeth M; Ravololomanana, Lisette; Razafimanantsoa, Lanto Tiana; Rakotojoelinandrasana, Tsanta; Razainirina, Josette; Hoffmann, Jonathan; Ravalohery, Jean-Pierre; Rafisandratantsoa, Jean-Théophile; Rollin, Pierre E; Reynes, Jean-Marc

    2010-06-01

    During 2 successive rainy seasons, January 2008 through May 2008 and November 2008 through March 2009, Rift Valley fever virus (RVFV) caused outbreaks in Madagascar. Human and animal infections were confirmed on the northern and southern coasts and in the central highlands. Analysis of partial sequences from RVFV strains showed that all were similar to the strains circulating in Kenya during 2006-2007. A national cross-sectional serologic survey among slaughterhouse workers at high risk showed that RVFV circulation during the 2008 outbreaks included all of the Malagasy regions and that the virus has circulated in at least 92 of Madagascar's 111 districts. To better predict and respond to RVF outbreaks in Madagascar, further epidemiologic studies are needed, such as RVFV complete genome analysis, ruminant movement mapping, and surveillance implementation.

  3. Socioeconomic Root Causes of Biodiversity Loss in Madagascar

    Treesearch

    Anitry N. Ratsifandrihamanana; Dawn Montanye; Sarah Christiansen; Sheila O' Connor

    2006-01-01

    In 2000 and 2001 a root cause analysis was conducted for the Spiny Forest Ecoregion in Madagascar, identifying the local level root causes of biodiversity loss in the ecoregion as well as the policy and institutional issues at the national and international levels that contribute to them. Most of the research was conducted in and around Tulear and Fort Dauphin....

  4. Six new species of Microdon Meigen from Madagascar (Diptera: Syrphidae).

    PubMed

    Reemer, Menno; Bot, Sander

    2015-10-28

    Six new species of the myrmecophilous hoverfly genus Microdon Meigen (Diptera: Syrphidae) are described from Madagascar. Redescriptions are given for the three other Madagascan species of this genus. Keys are presented to the Madagascan genera of the subfamily Microdontinae and to the Madagascan species of Microdon.

  5. Humicolous microcharmid scorpions: a new genus and species from Madagascar.

    PubMed

    Lourenço, Wilson R

    2004-01-01

    A new genus and species of humicolous microcharmid scorpion are described on the basis of a single specimen collected in the Ankarana Reserve, Madagascar. New considerations regarding the taxonomy and morphology of micro-buthoid Malagasy scorpions are proposed, based mainly on the study of the peg-shaped sensillae of the pectines by scanning electron microscopy.

  6. Has Madagascar Lost Its Exceptional Leptospirosis Free-Like Status?

    PubMed Central

    Ratsitorahina, Maherisoa; Rahelinirina, Soanandrasana; Michault, Alain; Rajerison, Minoarisoa; Rajatonirina, Soatiana; Richard, Vincent

    2015-01-01

    Background Leptospirosis is a widespread but underreported cause of morbidity and mortality. It has rarely been reported in either humans or animals in Madagascar. Methods We conducted a cross-sectional survey of the inhabitants in Moramanga, Madagascar, in June 2011, to estimate the prevalence of human infection using the microscopic agglutination test (MAT). This activity was carried out as part of a workshop implemented by the Pasteur Institute of Madagascar, focusing on surveillance with a one week field study and targeting the health staff of the district level. Results In total, we sampled 678 inhabitants from 263 households. The sex ratio (M/F) was 0.65 and the mean age 26.7 years. We obtained a value of 2.9% for the first recorded seroprevalence of this disease in the human community of Moramanga. Questionnaire responses revealed frequent contacts between humans and rodents in Moramanga. However, activities involving cattle were identified as a risk factor significantly associated with seropositivity (OR=3). Conclusion Leptospirosis remains a neglected disease in Madagascar. This study highlights the need to quantify the public health impact of this neglected disease in a more large scale, in all the country and to establish point-of-care laboratories in remote areas. PMID:25874381

  7. Has Madagascar lost its exceptional leptospirosis free-like status?

    PubMed

    Ratsitorahina, Maherisoa; Rahelinirina, Soanandrasana; Michault, Alain; Rajerison, Minoarisoa; Rajatonirina, Soatiana; Richard, Vincent

    2015-01-01

    Leptospirosis is a widespread but underreported cause of morbidity and mortality. It has rarely been reported in either humans or animals in Madagascar. We conducted a cross-sectional survey of the inhabitants in Moramanga, Madagascar, in June 2011, to estimate the prevalence of human infection using the microscopic agglutination test (MAT). This activity was carried out as part of a workshop implemented by the Pasteur Institute of Madagascar, focusing on surveillance with a one week field study and targeting the health staff of the district level. In total, we sampled 678 inhabitants from 263 households. The sex ratio (M/F) was 0.65 and the mean age 26.7 years. We obtained a value of 2.9% for the first recorded seroprevalence of this disease in the human community of Moramanga. Questionnaire responses revealed frequent contacts between humans and rodents in Moramanga. However, activities involving cattle were identified as a risk factor significantly associated with seropositivity (OR=3). Leptospirosis remains a neglected disease in Madagascar. This study highlights the need to quantify the public health impact of this neglected disease in a more large scale, in all the country and to establish point-of-care laboratories in remote areas.

  8. Genetic diversity of hepatitis B virus (HBV) in Madagascar.

    PubMed

    Andriamandimby, Soa Fy; Lo Presti, Alessandra; Lai, Alessia; Olive, Marie-Marie; Angeletti, Silvia; De Florio, Lucia; Cella, Eleonora; Razafindramparany, Minoharimbola; Ravalohery, Jean-Piere; Andriamamonjy, Seta; Gioffrè, Sonia; Zehender, Gianguglielmo; Mottini, Giovanni; Ciccozzi, Massimo; Heraud, Jean-Michel

    2016-12-01

    Hepatitis B virus (HBV) is a DNA virus belonging to Hepadnaviridae family. Chronic infection with HBV is one major risk factor of hepatic disease. In Madagascar, former studies classified the country as part of high endemic area, as HBV prevalence can reach 23% in general population. However, this prevalence differs largely between urban and rural areas and is estimated to be, respectively, 5% and 26%. The aims of the present study were to describe the genetic diversity of HBV strains from different regions of Madagascar, and to describe the viral gene flow throughout the country by using phylogenetic analysis. This is the first large-scale molecular and phylogenetic study analyzing HBV sequences from 28 different Malagasy areas, never sampled in the past. In this study, the most prevalent genotype/sub-genotypes was E. Migration analysis showed a gene flow from zone 3 (rural) to zone 2 (suburban), and a greater gene flow from the middle part of Madagascar to the north than to the south. It is important to study the HBV infections in Madagascar and to monitor the potential spread of this viral strain inside this country. J. Med. Virol. 88:2138-2144, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Earthshots: Satellite images of environmental change – Madagascar

    USGS Publications Warehouse

    Adamson, Thomas

    2016-01-01

    This ecoregion, which extends across southern and southwestern Madagascar, has a long dry season. Most of the rain falls from October to April, but rainfall amounts can be erratic. The plants’ unusual adaptations allow them to survive the long dry periods. But this ecoregion is experiencing rapid deforestation, which is evident in this Landsat series.

  10. A New Genus of Macropsinae (Hemiptera: Cicadellidae) From Madagascar.

    PubMed

    Yang, Liyuan; Dietrich, C H; Zhang, Yalin

    2016-01-01

    Paragalboa acuta GEN & SP N: is described and illustrated from Madagascar. The new genus shows morphological affinities to the Macropsini genus Galboa Distant recorded from Seychelles. A checklist of all known genera of Macropsinae is provided. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

  11. Family Background, School Characteristics, and Children's Cognitive Achievement in Madagascar

    ERIC Educational Resources Information Center

    Glick, Peter; Randrianarisoa, Jean Claude; Sahn, David E.

    2011-01-01

    This paper uses linked household, school, and test score data from Madagascar to investigate the relation of household characteristics and school factors to the cognitive skills of children ages 8-10 and 14-16. In contrast to most achievement test studies in developing countries, the study uses representative rather than school-based samples of…

  12. Interannual variability of rainfall characteristics over southwestern Madagascar

    NASA Astrophysics Data System (ADS)

    Randriamahefasoa, T. S. M.; Reason, C. J. C.

    2016-01-01

    The interannual variability of daily frequency of rainfall [>1 mm/day] and heavy rainfall [>30 mm/day] is studied for the southwestern region of Madagascar, which is relatively arid compared to the rest of the island. Attention is focused on the summer rainy season from December to March at four stations (Morondava, Ranohira, Toliara and Taolagnaro), whose daily rainfall data covering the period 1970-2000 were obtained from the Madagascar Meteorological Service. El Niño Southern Oscillation (ENSO) was found to have a relatively strong correlation with wet day frequency at each station and, particularly, for Toliara in the extreme southwest. In terms of seasonal rainfall totals, most El Niño (La Niña) summers receive below (above) average amounts. An ENSO connection with heavy rainfall events was less clear. However, for heavy rainfall events, the associated atmospheric circulation displays a Southern Annular Mode-like pattern throughout the hemisphere. For ENSO years and the neutral seasons 1979/80, 1981/82 which had large anomalies in wet day frequency, regional atmospheric circulation patterns consisted of strong anomalies in low-level moisture convergence and uplift over and near southwestern Madagascar that made conditions correspondingly more or less favourable for rainfall. Dry (wet) summers in southern Madagascar were also associated with an equatorward (poleward) displacement of the ITCZ in the region.

  13. Historical biogeography of the strepsirhine primates of Madagascar.

    PubMed

    Tattersall, Ian

    2006-01-01

    Lying some 400 km off the coast of southeastern Africa, Madagascar is the world's largest oceanic island. It has been in roughly the same position relative to its parent continent for 120 million years, and as a consequence its mammal fauna is unusual in composition, with a low number of major taxa but a high diversity at lower taxonomic levels. Among Madagascar's native terrestrial mammals, only the orders Primates, Rodentia, Carnivora and Insectivora are represented (plus, until recently, the enigmatic and endemic Bibymalagasia, and Artiodactyla in the form of semiaquatic pygmy hippopotamuses). This reflects the fact that terrestrial mammals are notoriously poor over-water dispersers; yet at the same time the ancestors of all of Madagascar's mammals had to have crossed a wide oceanic barrier to get to the island at various points during the Tertiary. Here I examine the palaeogeographic evidence for potential land bridge or 'stepping-stone' connections with adjacent continents from the Mesozoic through the Cenozoic, and review the fossil records and phylogenies of each of Madagascar's mammalian groups in an attempt to estimate the minimum number of crossings necessary to produce the island's current faunal composition. Probable monophyletic origins for each major group, and thus a smaller rather than a larger number of crossings of the Mozambique Channel, imply that this water barrier has acted as a powerful filter; so powerful that it is unclear whether any crossings would have been possible without some form of subaerial connection, however ephemeral, at least from time to time during the Tertiary. Clarification of how Madagascar's terrestrial mammal fauna may have originated is thus as likely to emerge from the geology of the seafloor surrounding the island as it is to come from the fossil record or from the internal and external relationships of its various components.

  14. Phylogeography and molecular epidemiology of Yersinia pestis in Madagascar.

    PubMed

    Vogler, Amy J; Chan, Fabien; Wagner, David M; Roumagnac, Philippe; Lee, Judy; Nera, Roxanne; Eppinger, Mark; Ravel, Jacques; Rahalison, Lila; Rasoamanana, Bruno W; Beckstrom-Sternberg, Stephen M; Achtman, Mark; Chanteau, Suzanne; Keim, Paul

    2011-09-01

    Plague was introduced to Madagascar in 1898 and continues to be a significant human health problem. It exists mainly in the central highlands, but in the 1990s was reintroduced to the port city of Mahajanga, where it caused extensive human outbreaks. Despite its prevalence, the phylogeography and molecular epidemiology of Y. pestis in Madagascar has been difficult to study due to the great genetic similarity among isolates. We examine island-wide geographic-genetic patterns based upon whole-genome discovery of SNPs, SNP genotyping and hypervariable variable-number tandem repeat (VNTR) loci to gain insight into the maintenance and spread of Y. pestis in Madagascar. We analyzed a set of 262 Malagasy isolates using a set of 56 SNPs and a 43-locus multi-locus VNTR analysis (MLVA) system. We then analyzed the geographic distribution of the subclades and identified patterns related to the maintenance and spread of plague in Madagascar. We find relatively high levels of VNTR diversity in addition to several SNP differences. We identify two major groups, Groups I and II, which are subsequently divided into 11 and 4 subclades, respectively. Y. pestis appears to be maintained in several geographically separate subpopulations. There is also evidence for multiple long distance transfers of Y. pestis, likely human mediated. Such transfers have resulted in the reintroduction and establishment of plague in the port city of Mahajanga, where there is evidence for multiple transfers both from and to the central highlands. The maintenance and spread of Y. pestis in Madagascar is a dynamic and highly active process that relies on the natural cycle between the primary host, the black rat, and its flea vectors as well as human activity.

  15. Corps de la Paix Madagascar Livre du Formateur. Langue: Sakalava (Peace Corps Madagascar Teacher's Manual. Language: Sakalava).

    ERIC Educational Resources Information Center

    Tshiangale, Mupemba Wa

    This teacher's manual for Sakalava, a dialect of Malagasy, is designed for the specific language instruction needs of Peace Corps personnel in Madagascar. It is written primarily in French and Sakalava, with some titles in English. It consists of 29 topical lessons, each geared to a specific domain and competency and containing information on…

  16. The Pselaphinae (Coleoptera: Staphylinidae) of Madagascar. V. Description of Squamiger elegans gen. et sp. nov. from Central Madagascar.

    PubMed

    Hlaváč, Peter; Baňař, Petr

    2016-06-23

    Squamiger elegans, gen. and sp. nov., is described based on a series of specimens collected by sifting of leaf-litter in Ambohitantely Special Reserve, Central Madagascar. The genus is a member of the tribe Clavigerini (Pselaphinae: Clavigeritae) and it is placed into the subtribe Clavigerodina.

  17. Corps de la Paix Madagascar Livre du Stagiare. Langue: Malagasy Ofisialy (Peace Corps Madagascar Volunteer Manual. Language: Official Malagasy).

    ERIC Educational Resources Information Center

    Tshiangale, Mupemba Wa

    This manual for Malagasy is designed for the specific language instruction needs of Peace Corps personnel working in Madagascar. It is written primarily in English and Malagasy, with introductory sections in French. It consists of 29 topical lessons, each geared to a specific domain and competency and containing information on needed materials,…

  18. The Application of TOMS Ozone, Aerosol and UV-B Data to Madagascar Air Quality Determination

    NASA Technical Reports Server (NTRS)

    Aikin, A.C.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Total Ozone Mapping Spectrometer (TOMS) data products for the area of Madagascar are presented. In addition to total ozone, aerosols and UV-B tropospheric ozone results are shown from 1979 to the present. Tropospheric ozone over Africa and Madagascar is enhanced by 10 to 15 DU in October. This maximum coincides with the time of maximum biomass area burning in Africa and Madagascar. Ozone observations were made from 1979 to 1999 using the TOMS tropospheric ozone convective cloud differential method. As a result of easterly trade winds, ozone originating on Madagascar is transported to the west over the Mozambique Channel. In El Nino years higher level westerly winds descend to transport low level ozone easterly. This results in African continental ozone being transported east of Madagascar. Long range transport of African ozone is observed during El Nino periods. The potential of TOMS and other space data for use in public education and research on Madagascar air quality is demonstrated.

  19. In situ observations of mesoscale undercurrents off eastern Madagascar

    NASA Astrophysics Data System (ADS)

    Ponsoni, Leandro; Aguiar-Gonzalez, Borja; Maas, Leo; van Aken, Hendrik; Nauw, Janine; Ridderinkhof, Herman

    2015-04-01

    The South-West Indian Ocean (SWIO) presents one of the most intriguing western boundary regions of all subtropical gyres. Unlike other gyres, in the SWIO the Madagascar island imposes a physical barrier to the westward flowing South Equatorial Current (SEC), which reaches the Madagascar coast between 17°S and 20°S. At this location, the SEC bifurcates into two branches: the poleward branch feeds into the East Madagascar Current (EMC), which further south will feed the Agulhas Current (AC); on the other hand, the poleward branch feeds into the North Madagascar Current (NMC), which turns around Cape Amber, at the northern tip of Madagascar, and continues westward towards the east coast of Africa. Besides the patterns of the boundary currents described above, undercurrents flowing opposite and beneath the mentioned surface currents are also reported to occur: the equatorward East Madagascar Undercurrent (EMUC) and the poleward North Madagascar Undercurrent (NMUC). This work is based on field studies of both undercurrents. We deployed a cross-slope array of five moorings at 23°S off eastern Madagascar, which was maintained from late 2010 till early 2013 (~2.5 years). A total of 6 Acoustic Doppler Current Profiles and 10 Recording Current Meters were coupled to the moorings. Direct measurements were made from near surface (~50 m) to deep in the water column (~4000 m). The observations reveal a recurring equatorward EMUC with its core hugging the continental slope, at a depth of 1260 m and at an approximate distance of 29 km from the coast. The core velocity has a mean value of 4.1 (±6.3) cm s-1, while maximum speeds reach up to 20 cm -1. The volume transport is estimated to be 1.33 (±1.14) Sv with maxima up to 6 Sv. At the northern tip of Madagascar, off Cape Ambar, we present the first observational evidence of a poleward NMUC. These results are based on a hydrographic cruise (March 2001), where vertical profiles of velocity were sampled across the continental

  20. Satellite Observations of Enhanced Tropospheric Ozone Associated with Biomass Burning in Africa and Madagascar

    NASA Technical Reports Server (NTRS)

    Aikin, A. C.; Ziemke, J. R.; Thorpe, A.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Tropospheric ozone over Africa and Madagascar is enhanced by 10 to 15 DU in October. This maximum coincides with the time of maximum biomass area burning in Africa and Madagascar. Ozone observations were made from 1979 to 1999 using the TOMS tropospheric ozone convective cloud differential method. As a result of easterly trade winds, ozone originating on Madagascar is transported to the west over the Mozambique Channel. In El Nino years higher level westerly winds descend to transport low level ozone easterly. This results in African continental ozone being transported east of Madagascar. Long range transport of African ozone is observed during El Nino periods.

  1. Implications of recent geological investigations of the Mozambique Channel for the mammalian colonization of Madagascar.

    PubMed

    McCall, R A

    1997-05-22

    Madagascar separated from continental Africa during the break-up of Gondwanaland early in the Cretaceous. The presence of several terrestrial mammalian groups on Madagascar is paradoxical as (i) these groups postdate the departure of Madagascar from Africa: and ii) terrestrial mammals are poor dispersers across wide water barriers. Recent geological studies focusing on the Davie Fracture Zone of the Mozambique Channel offer a resolution to this situation, by suggesting the presence of a land-bridge from the mid-Eocene to the early Miocene, an interval that matches the ages of Madagascar's mammalian groups.

  2. Extinction risks and the conservation of Madagascar's reptiles.

    PubMed

    Jenkins, Richard K B; Tognelli, Marcelo F; Bowles, Philip; Cox, Neil; Brown, Jason L; Chan, Lauren; Andreone, Franco; Andriamazava, Alain; Andriantsimanarilafy, Raphali R; Anjeriniaina, Mirana; Bora, Parfait; Brady, Lee D; Hantalalaina, Elisoa F; Glaw, Frank; Griffiths, Richard A; Hilton-Taylor, Craig; Hoffmann, Michael; Katariya, Vineet; Rabibisoa, Nirhy H; Rafanomezantsoa, Jeannot; Rakotomalala, Domoina; Rakotondravony, Hery; Rakotondrazafy, Ny A; Ralambonirainy, Johans; Ramanamanjato, Jean-Baptiste; Randriamahazo, Herilala; Randrianantoandro, J Christian; Randrianasolo, Harison H; Randrianirina, Jasmin E; Randrianizahana, Hiarinirina; Raselimanana, Achille P; Rasolohery, Andriambolantsoa; Ratsoavina, Fanomezana M; Raxworthy, Christopher J; Robsomanitrandrasana, Eric; Rollande, Finoana; van Dijk, Peter P; Yoder, Anne D; Vences, Miguel

    2014-01-01

    An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of

  3. Chapelieria magna, a new species of Rubiaceae from eastern Madagascar

    PubMed Central

    Kainulainen, Kent; Razafimandimbison, Sylvain G.

    2015-01-01

    Abstract A new species of Chapelieria was discovered during a recent field trip to the Masoala National Park in eastern Madagascar, and is described here as Chapelieria magna Kainul., sp. nov. This species is readily distinguishable from previously described species of the genus by its quadrangular shoots, triangular-calyptrate stipules, sessile leaves, pubescent styles, and ridged fruits. It also differs in the larger number of ovules and the much larger size of leaves and fruits. PMID:25698895

  4. The Pacification Campaign of Madagascar: 1896-1905

    DTIC Science & Technology

    2002-01-01

    during the early European period was Alfonso d’Albuquerque, governor of Portugal’s Indian Ocean possessions from 1508 to 1515. Rather than devoting his...emerged as the first president of Madagascar’s Third Republic. The leader of the Comité des Forces Vives (Vital Forces Committee, known as Forces Vives ...elections followed on November 25. Frontrunner Zafy won 46 percent of the popular vote as the Forces Vives candidate, and Ratsiraka, as leader of his own

  5. Multiple Miocene Melastomataceae dispersal between Madagascar, Africa and India.

    PubMed Central

    Renner, Susanne S

    2004-01-01

    Melastomataceae sensu stricto (excluding Memecylaceae) comprise some 3000 species in the neotropics, 1000 in Asia, 240 in Africa, and 230 in Madagascar. Previous family-wide morphological and DNA analyses have shown that the Madagascan species belong to at least three unrelated lineages, which were hypothesized to have arrived by trans-oceanic dispersal. An alternative hypothesis posits that the ancestors of Madagascan, as well as Indian, Melastomataceae arrived from Africa in the Late Cretaceous. This study tests these hypotheses in a Bayesian framework, using three combined sequence datasets analysed under a relaxed clock and simultaneously calibrated with fossils, some not previously used. The new fossil calibration comes from a re-dated possibly Middle or Upper Eocene Brazilian fossil of Melastomeae. Tectonic events were also tentatively used as constraints because of concerns that some of the family's fossils are difficult to assign to nodes in the phylogeny. Regardless of how the data were calibrated, the estimated divergence times of Madagascan and Indian lineages were too young for Cretaceous explanations to hold. This was true even of the oldest ages within the 95% credibility interval around each estimate. Madagascar's Melastomeae appear to have arrived from Africa during the Miocene. Medinilla, with some 70 species in Madagascar and two in Africa, too, arrived during the Miocene, but from Asia. Gravesia, with 100 species in Madagascar and four in east and west Africa, also appears to date to the Miocene, but its monophyly has not been tested. The study afforded an opportunity to compare divergence time estimates obtained earlier with strict clocks and single calibrations, with estimates based on relaxed clocks and different multiple calibrations and taxon sampling. PMID:15519967

  6. Extinction Risks and the Conservation of Madagascar's Reptiles

    PubMed Central

    Jenkins, Richard K. B.; Tognelli, Marcelo F.; Bowles, Philip; Cox, Neil; Brown, Jason L.; Chan, Lauren; Andreone, Franco; Andriamazava, Alain; Andriantsimanarilafy, Raphali R.; Anjeriniaina, Mirana; Bora, Parfait; Brady, Lee D.; Hantalalaina, Elisoa F.; Glaw, Frank; Griffiths, Richard A.; Hilton-Taylor, Craig; Hoffmann, Michael; Katariya, Vineet; Rabibisoa, Nirhy H.; Rafanomezantsoa, Jeannot; Rakotomalala, Domoina; Rakotondravony, Hery; Rakotondrazafy, Ny A.; Ralambonirainy, Johans; Ramanamanjato, Jean-Baptiste; Randriamahazo, Herilala; Randrianantoandro, J. Christian; Randrianasolo, Harison H.; Randrianirina, Jasmin E.; Randrianizahana, Hiarinirina; Raselimanana, Achille P.; Rasolohery, Andriambolantsoa; Ratsoavina, Fanomezana M.; Raxworthy, Christopher J.; Robsomanitrandrasana, Eric; Rollande, Finoana; van Dijk, Peter P.; Yoder, Anne D.; Vences, Miguel

    2014-01-01

    Background An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Methodology/Principal Findings Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. Conclusions/Significance With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and

  7. Origin and Diversification of Dung Beetles in Madagascar

    PubMed Central

    Miraldo, Andreia; Wirta, Helena; Hanski, Ilkka

    2011-01-01

    Madagascar has a rich fauna of dung beetles (Scarabaeinae and Aphodiinae) with almost 300 species described to date. Like most other taxa in Madagascar, dung beetles exhibit an exceptionally high level of endemism (96% of the species). Here, we review the current knowledge of the origin and diversification of Malagasy dung beetles. Based on molecular phylogenies, the extant dung beetles originate from eight colonizations, of which four have given rise to extensive radiations. These radiations have occurred in wet forests, while the few extant species in the less successful radiations occur in open and semi-open habitats. We discuss the likely mechanisms of speciation and the ecological characteristics of the extant communities, emphasizing the role of adaptation along environmental gradients and allopatric speciation in generating the exceptionally high beta diversity in Malagasy dung beetles. Phylogeographic analyses of selected species reveal complex patterns with evidence for genetic introgression between old taxa. The introduction of cattle to Madagascar 1500 years ago created a new abundant resource, onto which a few species have shifted and thereby been able to greatly expand their geographical ranges. PMID:26467617

  8. Sporormiella and the late Holocene extinctions in Madagascar

    PubMed Central

    Burney, David A.; Robinson, Guy S.; Burney, Lida Pigott

    2003-01-01

    Fossil spores of the dung fungus Sporormiella spp. in sediment cores from throughout Madagascar provide new information concerning megafaunal extinction and the introduction of livestock. Sporormiella percentages are very high in prehuman southwest Madagascar, but at the site with best stratigraphic resolution the spore declines sharply by ≈1,720 yr B.P. (radiocarbon years ago). Within a few centuries there is a concomitant rise in microscopic charcoal that probably represents human transformation of the local environment. Reduced megaherbivore biomass in wooded savannas may have resulted in increased plant biomass and more severe fires. Some now-extinct taxa persisted locally for a millennium or more after the inferred megafaunal decline. Sites in closed humid forests of northwest Madagascar and a montane ericoid formation of the central highlands show only low to moderate Sporormiella percentages before humans. A subsequent rise in spore concentrations, thought to be evidence for livestock proliferation, occurs earliest at Amparihibe in the northwest at ≈1,130 yr B.P. PMID:12960385

  9. Xenopsylla cheopis (Siphonaptera: Pulicidae) Susceptibility to Deltamethrin in Madagascar

    PubMed Central

    Elissa, Nohal

    2014-01-01

    The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae), to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%): only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down) and KD90 (90% Knock-Down) times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar. PMID:25369291

  10. Xenopsylla cheopis (Siphonaptera: Pulicidae) susceptibility to Deltamethrin in Madagascar.

    PubMed

    Boyer, Sebastien; Miarinjara, Adélaïde; Elissa, Nohal

    2014-01-01

    The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae), to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%): only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down) and KD90 (90% Knock-Down) times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar.

  11. Sarandibrinus, a new genus of Saprininae subfamily from Madagascar (Coleoptera, Histeridae) (Second contribution to the knowledge of the Histeridae of Madagascar).

    PubMed

    Lackner, Tomáš; Gomy, Yves

    2014-01-01

    Sarandibrinus araceliae, a new genus and species of the Saprininae subfamily is described from southern Madagascar. The new taxon exhibits autapomorphic characters for the Saprininae subfamily and is unusual especially for its large and deep prosternal foveae and the shape of spiculum gastrale. The description is accompanied by color habitus images, SEM micrographs, mouthparts and antenna line drawings and drawings of the male genitalia. Key to the genera of the Saprininae of Madagascar and the adjacent archipelagos is given. Hypocaccus (Baeckmanniolus) rubiciliae (Lewis, 1899) is newly reported from Madagascar and Hypocaccus (Nessus) perparvulus (Desbordes, 1916) is new to Mauritius.

  12. The structure of the crust and uppermost mantle beneath Madagascar

    NASA Astrophysics Data System (ADS)

    Andriampenomanana, Fenitra; Nyblade, Andrew A.; Wysession, Michael E.; Durrheim, Raymond J.; Tilmann, Frederik; Julià, Jordi; Pratt, Martin J.; Rambolamanana, Gérard; Aleqabi, Ghassan; Shore, Patrick J.; Rakotondraibe, Tsiriandrimanana

    2017-09-01

    The lithosphere of Madagascar was initially amalgamated during the Pan-African events in the Neoproterozoic. It has subsequently been reshaped by extensional processes associated with the separation from Africa and India in the Jurassic and Cretaceous, respectively, and been subjected to several magmatic events in the late Cretaceous and the Cenozoic. In this study, the crust and uppermost mantle have been investigated to gain insights into the present-day structure and tectonic evolution of Madagascar. We analysed receiver functions, computed from data recorded on 37 broad-band seismic stations, using the H-κ stacking method and a joint inversion with Rayleigh-wave phase-velocity measurements. The thickness of the Malagasy crust ranges between 18 and 46 km. It is generally thick beneath the spine of mountains in the centre part (up to 46 km thick) and decreases in thickness towards the edges of the island. The shallowest Moho is found beneath the western sedimentary basins (18 km thick), which formed during both the Permo-Triassic Karro rifting in Gondwana and the Jurassic rifting of Madagascar from eastern Africa. The crust below the sedimentary basin thickens towards the north and east, reflecting the progressive development of the basins. In contrast, in the east there was no major rifting episode. Instead, the slight thinning of the crust along the east coast (31-36 km thick) may have been caused by crustal uplift and erosion when Madagascar moved over the Marion hotspot and India broke away from it. The parameters describing the crustal structure of Archean and Proterozoic terranes, including average thickness (40 km versus 35 km), Poisson's ratio (0.25 versus 0.26), average shear-wave velocity (both 3.7 km s-1), and thickness of mafic lower crust (7 km versus 4 km), show weak evidence of secular variation. The uppermost mantle beneath Madagascar is generally characterized by shear-wave velocities typical of stable lithosphere (∼4.5 km s-1). However

  13. A geological synthesis of the Precambrian shield in Madagascar

    USGS Publications Warehouse

    Tucker, Robert D.; Roig, J.Y.; Moine, B.; Delor, C.; Peters, S.G.

    2014-01-01

    Available U–Pb geochronology of the Precambrian shield of Madagascar is summarized and integrated into a synthesis of the region’s geological history. The shield is described in terms of six geodynamic domains, from northeast to southwest, the Bemarivo, Antongil–Masora, Antananarivo, Ikalamavony, Androyan–Anosyan, and Vohibory domains. Each domain is defined by distinctive suites of metaigneous rocks and metasedimentary groups, and a unique history of Archean (∼2.5 Ga) and Proterozoic (∼1.0 Ga, ∼0.80 Ga, and ∼0.55 Ga) reworking. Superimposed within and across these domains are scores of Neoproterozoic granitic stocks and batholiths as well as kilometer long zones of steeply dipping, highly strained rocks that record the effects of Gondwana’s amalgamation and shortening in latest Neoproterozoic time (0.560–0.520 Ga). The present-day shield of Madagascar is best viewed as part of the Greater Dharwar Craton, of Archean age, to which three exotic terranes were added in Proterozoic time. The domains in Madagascar representing the Greater Dharwar Craton include the Antongil–Masora domain, a fragment of the Western Dharwar of India, and the Neoarchean Antananarivo domain (with its Tsaratanana Complex) which is broadly analogous to the Eastern Dharwar of India. In its reconstructed position, the Greater Dharwar Craton consists of a central nucleus of Paleo-Mesoarchean age (>3.1 Ga), the combined Western Dharwar and Antongil–Masora domain, flanked by mostly juvenile “granite–greenstone belts” of Neoarchean age (2.70–2.56 Ga). The age of the accretionary event that formed this craton is approximately 2.5–2.45 Ga. The three domains in Madagascar exotic to the Greater Dharwar Craton are the Androyan–Anosyan, Vohibory, and Bemarivo. The basement to the Androyan–Anosyan domain is a continental terrane of Paleoproterozoic age (2.0–1.78 Ga) that was accreted to the southern margin (present-day direction) of the Greater Dharwar Craton in pre

  14. The modern diatom spectra of Madagascar and diatom-inferred Late Quaternary climatic changes in northeastern and central Madagascar

    SciTech Connect

    Reyes, N.E.

    1993-01-01

    A study was conducted to classify diatoms in modern sediment surface samples in freshwater sites into assemblages and to assess the historical changes in lake level changes and climatic conditions in Madagascar during the Late Quaternary. Analysis of taxonomic percentages of diatoms in recently deposited sediments from various sites shows that diatom communities in these sites can be grouped by means of cluster analysis into distinct assemblages, some of which show similarities to groupings found in East Africa. pH and conductivity appear to be important factors correlating with differences in diatom communities in these study sites. Trends in diatom assemblages in a sediment core taken from Lake Alaotra, supplemented by those in sediments of the paleolake Ampasambazimba, suggest that the late Pleistocene in northeastern Madagascar was arid, though aridity was probably not as constant or as severe as in many areas of eastern and northern Africa; the Holocene was a period of moderate but variable conditions, marked by a distinct dry episode ca 5000 yr B.P. and a drying trend toward the late Holocene. Changes in diatom assemblages in a sediment core from Lake Kavitaha in central Madagascar suggest changes in the surrounding environment during at least two periods in the late Holocene. These coincide with increases in charcoal influx and, around 700 yr B.P., with the intensification of agricultural activity in the area.

  15. Chow Down! Using Madagascar Hissing Cockroaches to Explore Basic Nutrition Concepts

    ERIC Educational Resources Information Center

    Wagler, Ron

    2009-01-01

    The Madagascar hissing cockroach ("Gromphadorhina portentosa") is one of the most exciting and enjoyable animals to incorporate into your science curriculum. Madagascar hissing cockroaches (MHCs) do not bite, are easy to handle, produce little odor compared to many terrarium animals, have a fascinating social structure, are easy to breed, teach…

  16. Rain Forest Tourism - Estimating the Benefits of Tourism Development in a New National Park in Madagascar

    Treesearch

    D. Evan Mercer; R. Kramer; N. Sharma

    1995-01-01

    Travel cost and contingent valuation methods are applied to the problem of estimating the potential consumer surplus available to international nature tourists from a rain forest conservation project in Madagascar. Data are derived from surveys of nature tourists in Madagascar and international, nature tourism professionals in the U.S. and Europe. Typical trip travel...

  17. New and little known species of ptyctimous mites (Acari, Oribatida) from Madagascar.

    PubMed

    Niedbała, Wojciech; Starý, Josef

    2016-04-18

    In six sifting litter samples from Madagascar, altogether 26 species of ptyctimous mites, belonging to four families and 11 genera, were found. Three new species, Arphthicarus phoxos sp. nov., Notophthiracarus parapaulianus sp. nov. and Atropacarus (Hoplophorella) paralemurius sp. nov. are described and figured. Keys for species of genera and subgenera Arphthicarus, Notophthiracarus and Atropacarus (Hoplophorella) from Madagascar are presented.

  18. Chow Down! Using Madagascar Hissing Cockroaches to Explore Basic Nutrition Concepts

    ERIC Educational Resources Information Center

    Wagler, Ron

    2009-01-01

    The Madagascar hissing cockroach ("Gromphadorhina portentosa") is one of the most exciting and enjoyable animals to incorporate into your science curriculum. Madagascar hissing cockroaches (MHCs) do not bite, are easy to handle, produce little odor compared to many terrarium animals, have a fascinating social structure, are easy to breed, teach…

  19. Broken forest: Applying the integrated conservation and development paradigm to Madagascar's protected areas

    SciTech Connect

    Barbour, R.; Rabezandria, R.; Daviesson, R.; Guyton, W.; Rakotobe.

    1992-06-01

    The destruction of Madagascar's primary forests through agricultural clearing poses a grave threat to the island's biodiversity. The report assesses the potential of the planned Sustainable and Viable Environmental Management (SAVEM) Project to minimize this threat by implementing Integrated Conservation Development Projects (ICDP's), which link resource conservation to income-generating activities, in the peripheral zones of Madagascar's protected areas.

  20. Mapping the Traces of the Assembly and Multistage Breakup of Gondwanaland in the Lithosphere of Madagascar

    NASA Astrophysics Data System (ADS)

    Rindraharisaona, E. J.; Tilmann, F. J.; Yuan, X.; Rumpker, G.; Heit, B.; Rambolamanana, G.; Priestley, K. F.

    2014-12-01

    Madagascar is an ideal place to study the multistage assembly and break up of Gondwanaland, the supercontinent whose breakup also gave rise to most of present day continental regions. At the end of the Proterozoic the assembly of Gondwanaland has placed the Malagasy basement between the Antarctic, Dharwar, Arabo-Nubian and Nubian-Tanzanian cratons. The continental collision processes accompanying the assembly left their mark on the Malagasy basement, currently exposed in the Eastern two thirds of the island, in the form of metamorphic and mineral belts as well as massive ductile shear zones. During the Jurassic Madagascar, India and Seychelles were breaking up from African. Long after the breakaway of India and the Seychelles from Madagascar (Cretaceous time), volcanic activation has occurred in several locations of Madagascar mostly in the central and northern part (Neogene period). The surface traces of assembly and breakup processes have been studied extensively using geological methods in Madagascar but the imprint on the deep structure has so far not been studied in much detail. Between 2012 and 2014, 25 broadband stations were operated in the Southern Madagascar extending from East coast (Mananjary) to West coast (Toliary). The array crosses the Bongolava-Ranontsara shear zone, which is one of the major shear zones in Madagascar. In addition, between 2013 and 2014, 25 short period stations were deployed in the southeastern part of Madagascar. We will present preliminarily results of the lithosphere structure in the southern part of Madagascar based on surface wave dispersion analysis from both earthquakes and ambient noise combine with receiver function analysis. We will focus mostly on the contrast between the lithosphere structure in the eastern (Precambrian rocks) and the western (Sedimentary basins) parts of Madagascar.

  1. Cenozoic Uplift, Erosion and Dynamic Support of Madagascar

    NASA Astrophysics Data System (ADS)

    Stephenson, Simon; White, Nicky

    2016-04-01

    The physiography of Madagascar is characterised by high-elevation but low-relief topography; 42% of the landscape is above 500 m in elevation. Eocene (marine) nummulitic (marine) limestones at elevations of ˜400 m above sea level and newly dated, emergent 125 ka coral reefs suggest that Madagascar has experienced differential vertical motions during Cenozoic times. Malagasy rivers are often deeply incised and contain steepened reaches, implying that they have responded to changes in regional uplift rate. However, low temperature thermochronology and 10Be derived erosion rates suggest that both Cenozoic and Recent average denudation rates have been low. Extensive laterite-capped, low-relief surfaces also suggest that there have been long periods of tectonic quiescence. In contrast, the modern landscape is characterised by erosional gullies (i.e. lavaka), with very high local erosion rates. To bridge the gap between this disparate evidence, we inverted 2566 longitudinal river profiles using a damped non-negative, least-squares linear inversion to determine the history of regional uplift. We used a simplified version of the stream power erosional law. River profiles were extracted from the 3 arc-second Shuttle Radar Topography Mission (SRTM) digital elevation model. Calibration of the stream power erosional law is based upon Cenozoic limestones and new radiometrically dated marine terraces. The residual misfit between observed and calculated river profiles is small. Results suggest that Malagasy topography grew diachronously by 1-2 km over the last 15-20 Ma. Calculated uplift and denudation are consistent with independent observations. Thus drainage networks contain coherent signals that record regional uplift. The resultant waves of incision are the principal trigger for modern erosional processes. Admittance calculations, the history of basaltic volcanism and nearby oceanic residual age-depth measurements all suggest that as much as 0.8 - 1.1 km of Cenozoic uplift

  2. Age-specific seroprevalence of hepatitis A in Antananarivo (Madagascar)

    PubMed Central

    Raharimanga, Vaomalala; Carod, Jean-François; Ramarokoto, Charles-Emile; Chrétien, Jean-Baptiste; Rakotomanana, Fanjasoa; Talarmin, Antoine; Richard, Vincent

    2008-01-01

    Background Hepatitis A virus (HAV) is an enteric, viral, infectious disease endemic in many developing countries such as Madagascar. Infection is often subclinical or asymptomatic in children; however, symptomatic acute infections become more common with increasing age. In some developing countries, improvements in living conditions have led to changes in the epidemiological pattern of HAV infection. There are very few reports on the prevalence of HAV in Madagascar. This study was to determine the seroprevalence of hepatitis A virus antibodies in relation to age in the city of Antananarivo, Madagascar. Methods Serum samples collected in 2004 during a cross-sectional survey of individuals aged between two and 24 years from Antananarivo were tested for anti-HAV antibody using a commercial enzyme immunoassay kit. Subjects were investigated using a standardized social and medical history questionnaire. Results 926 subjects were enrolled including 406 males and 520 females. There were 251 children under 10 years old and 675 subjects between 10 and 24 years old. Of the 926 serum samples tested, 854 (92.2%) were positive for anti-HAV antibodies. The number of seropositive samples was similar for males and females. The overall seroprevalence was 83.7% (210/251) for children under 10 years old and 95.5% (644/675) for subjects aged between 10 and 24 years (p < 0.001). Conclusion Despite improvements in sanitary conditions and hygiene over the last few years, the prevalence of HAV in Antananarivo is high. Only children under five years old remain susceptible to HAV infection. Immunization against HAV is not needed at the present time in the Madagascan population, but should be recommended for travellers. PMID:18538023

  3. A juvenile subfossil crocodylian from Anjohibe Cave, Northwestern Madagascar.

    PubMed

    Mathews, Joshua C; Samonds, Karen E

    2016-01-01

    Madagascar's subfossil record preserves a diverse community of animals including elephant birds, pygmy hippopotamus, giant lemurs, turtles, crocodiles, bats, rodents, and carnivorans. These fossil accumulations give us a window into the island's past from 80,000 years ago to a mere few hundred years ago, recording the extinction of some groups and the persistence of others. The crocodylian subfossil record is limited to two taxa, Voay robustus and Crocodylus niloticus, found at sites distributed throughout the island. V. robustus is extinct while C. niloticus is still found on the island today, but whether these two species overlapped temporally, or if Voay was driven to extinction by competing with Crocodylus remains unknown. While their size and presumed behavior was similar to each other, nearly nothing is known about the growth and development of Voay, as the overwhelming majority of fossil specimens represent mature adult individuals. Here we describe a nearly complete juvenile crocodylian specimen from Anjohibe Cave, northwestern Madagascar. The specimen is referred to Crocodylus based on the presence of caviconchal recesses on the medial wall of the maxillae, and to C. niloticus based on the presence of an oval shaped internal choana, lack of rostral ornamentation and a long narrow snout. However, as there are currently no described juvenile specimens of Voay robustus, it is important to recognize that some of the defining characteristics of that genus may have changed through ontogeny. Elements include a nearly complete skull and many postcranial elements (cervical, thoracic, sacral, and caudal vertebrae, pectoral elements, pelvic elements, forelimb and hindlimb elements, osteoderms). Crocodylus niloticus currently inhabits Madagascar but is locally extinct from this particular region; radiometric dating indicates an age of ∼460-310 years before present (BP). This specimen clearly represents a juvenile based on the extremely small size and open sutures

  4. [AIDS in Madagascar. I. Epidemiology, projections, socioeconomic impact, interventions].

    PubMed

    Andriamahenina, R; Ravelojaona, B; Rarivoharilala, E; Ravaoarimalala, C; Andriamiadana, J; Andriamahefazafy, B; May, J F; Behets, F; Rasamindrakotroka, A

    1998-01-01

    Madagascar is still among the rare states of low prevalence of HIV. The seroprevalence rate is nevertheless rising. The aim of this study is to show the current view of the epidemic, its future tendency, its economical and social impact on people and what measures to be taken at the national scale. In Madagascar, we can state by 1995 20 cases of notified AIDS and probably 130 cases of non-notified AIDS. Seroprevalence data are collected every year by the National Reference Laboratory STD/AIDS. But, they are insufficient to estimate the number of infected people. So, they had been completed by a serosurveillance study of AIDS and syphilis in middle of 1995 and at the beginning of 1996. Pregnant women, persons with STDs and prostitutes are been screened in the six biggest cities of the Island. Results show, not only a high prevalence of syphilis, but also indicate that now, we have about 5,000 seropositive people in the country. Besides, by the number of people with STDs, it is estimated that one million Malgasy adults risk to be infected. Based on estimates of the epidemic, be it the cases of a high scenario, (Kenya) or of a low one (Thailand) by the year 2015, the seroprevalence rate could represent 3% or 15% of adults. Demographic consequences of the epidemic will be serious, particularly if HIV spreads quickly. Nevertheless, it does not stop the increase of population. Therefore, there will be more infected people with the disease, especially young people between 15 and 49 years old. The increase of dead people will be serious. Social consequences of the epidemic (case of high scenario) will be gravely felt, in particular by the rise of the number of AIDS orphans. Tuberculosis outbreak can be observed too. This disease is already a serious problem in Madagascar. At last, the epidemic will bring with it a high increase of money spent on health and will have grave consequences on agriculture, industry and commerce. Nevertheless, Madagascar still benefit a big luck

  5. Control of cysticercosis in Madagascar: beware of the pitfalls.

    PubMed

    Rasamoelina-Andriamanivo, Harentsoaniaina; Porphyre, Vincent; Jambou, Ronan

    2013-11-01

    Taenia solium cysticercosis is a zoonosis of public health importance in areas where the disease is endemic, with significant economic impacts on human health and the swine industry. Several gaps remain in the epidemiology of the parasite and the strategies of control in developing countries. We detail the key factors to consider in Madagascar in terms of the porcine husbandry system, Taenia transmission cycle, and diagnosis of cysticercosis in pigs, in order to better estimate the sanitary and economic impacts of this parasitic disease as well as to define an integrated control program. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Geological evolution of the Neoproterozoic Bemarivo Belt, northern Madagascar

    USGS Publications Warehouse

    Thomas, Ronald J.; De Waele, B.; Schofield, D.I.; Goodenough, K.M.; Horstwood, M.; Tucker, R.; Bauer, W.; Annells, R.; Howard, K. J.; Walsh, G.; Rabarimanana, M.; Rafahatelo, J.-M.; Ralison, A.V.; Randriamananjara, T.

    2009-01-01

    The broadly east-west trending, Late Neoproterozoic Bemarivo Belt in northern Madagascar has been re-surveyed at 1:100 000 scale as part of a large multi-disciplinary World Bank-sponsored project. The work included acquisition of 14 U-Pb zircon dates and whole-rock major and trace element geochemical data of representative rocks. The belt has previously been modelled as a juvenile Neoproterozoic arc and our findings broadly support that model. The integrated datasets indicate that the Bemarivo Belt is separated by a major ductile shear zone into northern and southern "terranes", each with different lithostratigraphy and ages. However, both formed as Neoproterozoic arc/marginal basin assemblages that were translated southwards over the north-south trending domains of "cratonic" Madagascar, during the main collisional phase of the East African Orogeny at ca. 540 Ma. The older, southern terrane consists of a sequence of high-grade paragneisses (Sahantaha Group), which were derived from a Palaeoproterozoic source and formed a marginal sequence to the Archaean cratons to the south. These rocks are intruded by an extensive suite of arc-generated metamorphosed plutonic rocks, known as the Antsirabe Nord Suite. Four samples from this suite yielded U-Pb SHRIMP ages at ca. 750 Ma. The northern terrane consists of three groups of metamorphosed supracrustal rocks, including a possible Archaean sequence (Betsiaka Group: maximum depositional age approximately 2477 Ma) and two volcano-sedimentary sequences (high-grade Milanoa Group: maximum depositional age approximately 750 Ma; low grade Daraina Group: extrusive age = 720-740 Ma). These supracrustal rocks are intruded by another suite of arc-generated metamorphosed plutonic rocks, known as the Manambato Suite, 4 samples of which gave U-Pb SHRIMP ages between 705 and 718 Ma. Whole-rock geochemical data confirm the calc-alkaline, arc-related nature of the plutonic rocks. The volcanic rocks of the Daraina and Milanoa groups also

  7. Terraced agriculture protects soil from erosion: Case studies in Madagascar

    NASA Astrophysics Data System (ADS)

    Rabesiranana, Naivo; Rasolonirina, Martin; Fanantenansoa Solonjara, Asivelo; Nomenjanahary Ravoson, Heritiana; Mabit, Lionel

    2016-04-01

    - Soil degradation is a major concern in Madagascar but quantitative information is not widely available. Due to its impact on the sustainability of agricultural production, there is a clear need to acquire data on the extent and magnitude of soil erosion/sedimentation under various agricultural practices in order to promote effective conservation strategies. Caesium-137 and 210Pbex fallout radionuclides (FRNs) possess particular characteristics that make them effective soil tracers for erosion studies. After fallout, 137Cs and 210Pbex are rapidly adsorbed onto fine soil particles. But to date, combined use of these FRNs has never been used to document soil erosion in Madagascar. The study area is located 40 km east of Antananarivo, in Madagascar highlands. Two adjacent cultivated fields have been selected (i.e. a sloped field and a terraced field) as well as an undisturbed reference site in the vicinity of these agricultural fields. Soil samples were collected along downslope transects using motorized corer. The 137Cs and 210Pb gamma analysis were performed at the Institut National des Sciences et Techniques Nucléaires (INSTN-Madagascar) using a high resolution and low background N-type HPGe detector. Results showed that at the terraced field, 137Cs and 210Pbex inventories reached 145 Bq/m2 to 280 Bq/m2 and 2141 Bq/m2 to 4253 Bq/m2, respectively. At the sloped field, the 137Cs and 210Pbex inventories values ranged from 110 Bq/m2 to 280 Bq/m2 and from 2026 Bq/m2 to 4110 Bq/m2, respectively. The net soil erosion determined for the sloped field were 9.6 t/ha/y and 7.2 t/ha/y for 137Cs and 210Pbex methods, respectively. In contrast, at the terraced field, the net soil erosion rates reached only 3.4 t/ha/y and 3.8 t/ha/y, respectively. The preliminary results of this research highlighted that terraced agricultural practice provides an efficient solution to protect soil resources of the Malagasy highlands.

  8. Proterozoic tectonostratigraphy and paleogeography of central Madagascar derived from detrital zircon U-Pb age populations

    USGS Publications Warehouse

    Cox, R.; Coleman, D.S.; Chokel, C.B.; DeOreo, S.B.; Wooden, J.L.; Collins, A.S.; De Waele, B.; Kroner, A.

    2004-01-01

    Detrital zircon U-Pb ages determined by SHRIMP distinguish two clastic sequences among Proterozoic metasedimentary rocks from central Madagascar. The Itremo Group is older: zircon data, stromatolite characteristics, and carbon isotope data all point to a depositional age around 1500-1700 Ma. The Molo Group is younger, deposited between ???620 Ma (the age of the youngest zircon) and ???560 Ma (the age of metamorphic overgrowths on detrital cores). Geochronologic provenance analysis of the Itremo Group points to sources in East Africa as well as local sources in central and southern Madagascar but provides no evidence for a detrital contribution from northern and eastern Madagascar nor from southern India. Detrital zircon and sedimentologic similarities between rocks of the Itremo Group and the Zambian Muva Supergroup suggest a lithostratigraphic correlation between the two. The Molo Group has a strong 1000-1100 Ma detrital signature that also indicates an east African provenance and suggests a Neoproterozoic geographic connection with Sri Lanka but shows no indication of input from the Dharwar craton and eastern Madagascar. Central Madagascar was probably juxtaposed with the Tanzanian craton in the Paleo- and Mesoproterozoic, whereas northern and eastern Madagascar were connected to India. Internal assembly of Madagascar postdates Neoproterozoic Molo Group sedimentation and is likely to have occurred at about 560 Ma. ?? 2004 by The University of Chicago. All rights reserved.

  9. Migration, isolation and hybridization in island crop populations: the case of Madagascar rice.

    PubMed

    Mather, Kristie A; Molina, Jeanmaire; Flowers, Jonathan M; Rubinstein, Samara; Rauh, Brad L; Lawton-Rauh, Amy; Caicedo, Ana L; McNally, Kenneth L; Purugganan, Michael D

    2010-11-01

    Understanding how crop species spread and are introduced to new areas provides insights into the nature of species range expansions. The domesticated species Oryza sativa or Asian rice is one of the key domesticated crop species in the world. The island of Madagascar off the coast of East Africa was one of the last major Old World areas of introduction of rice after the domestication of this crop species and before extensive historical global trade in this crop. Asian rice was introduced in Madagascar from India, the Malay Peninsula and Indonesia approximately 800-1400 years ago. Studies of domestication traits characteristic of the two independently domesticated Asian rice subspecies, indica and tropical japonica, suggest two major waves of migrations into Madagascar. A population genetic analysis of rice in Madagascar using sequence data from 53 gene fragments provided insights into the dynamics of island founder events during the expansion of a crop species' geographic range and introduction to novel agro-ecological environments. We observed a significant decrease in genetic diversity in rice from Madagascar when compared to those in Asia, likely the result of a bottleneck on the island. We also found a high frequency of a unique indica type in Madagascar that shows clear population differentiation from most of the sampled Asian landraces, as well as differential exchange of alleles between Asia and Madagascar populations of the tropical japonica subspecies. Finally, despite partial reproductive isolation between japonica and indica, there was evidence of indica/japonica recombination resulting from their hybridization on the island.

  10. A non-stationary relationship between global climate phenomena and human plague incidence in Madagascar.

    PubMed

    Kreppel, Katharina S; Caminade, Cyril; Telfer, Sandra; Rajerison, Minoarison; Rahalison, Lila; Morse, Andy; Baylis, Matthew

    2014-10-01

    Plague, a zoonosis caused by Yersinia pestis, is found in Asia and the Americas, but predominantly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. Plague's occurrence is affected by local climate factors which in turn are influenced by large-scale climate phenomena such as the El Niño Southern Oscillation (ENSO). The effects of ENSO on regional climate are often enhanced or reduced by a second large-scale climate phenomenon, the Indian Ocean Dipole (IOD). It is known that ENSO and the IOD interact as drivers of disease. Yet the impacts of these phenomena in driving plague dynamics via their effect on regional climate, and specifically contributing to the foci of transmission on Madagascar, are unknown. Here we present the first analysis of the effects of ENSO and IOD on plague in Madagascar. We use a forty-eight year monthly time-series of reported human plague cases from 1960 to 2008. Using wavelet analysis, we show that over the last fifty years there have been complex non-stationary associations between ENSO/IOD and the dynamics of plague in Madagascar. We demonstrate that ENSO and IOD influence temperature in Madagascar and that temperature and plague cycles are associated. The effects on plague appear to be mediated more by temperature, but precipitation also undoubtedly influences plague in Madagascar. Our results confirm a relationship between plague anomalies and an increase in the intensity of ENSO events and precipitation. This work widens the understanding of how climate factors acting over different temporal scales can combine to drive local disease dynamics. Given the association of increasing ENSO strength and plague anomalies in Madagascar it may in future be possible to forecast plague outbreaks in Madagascar. The study gives insight into the complex and changing relationship between climate factors and plague in Madagascar.

  11. A Non-Stationary Relationship between Global Climate Phenomena and Human Plague Incidence in Madagascar

    PubMed Central

    Kreppel, Katharina S.; Caminade, Cyril; Telfer, Sandra; Rajerison, Minoarison; Rahalison, Lila; Morse, Andy; Baylis, Matthew

    2014-01-01

    Background Plague, a zoonosis caused by Yersinia pestis, is found in Asia and the Americas, but predominantly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. Plague's occurrence is affected by local climate factors which in turn are influenced by large-scale climate phenomena such as the El Niño Southern Oscillation (ENSO). The effects of ENSO on regional climate are often enhanced or reduced by a second large-scale climate phenomenon, the Indian Ocean Dipole (IOD). It is known that ENSO and the IOD interact as drivers of disease. Yet the impacts of these phenomena in driving plague dynamics via their effect on regional climate, and specifically contributing to the foci of transmission on Madagascar, are unknown. Here we present the first analysis of the effects of ENSO and IOD on plague in Madagascar. Methodology/principal findings We use a forty-eight year monthly time-series of reported human plague cases from 1960 to 2008. Using wavelet analysis, we show that over the last fifty years there have been complex non-stationary associations between ENSO/IOD and the dynamics of plague in Madagascar. We demonstrate that ENSO and IOD influence temperature in Madagascar and that temperature and plague cycles are associated. The effects on plague appear to be mediated more by temperature, but precipitation also undoubtedly influences plague in Madagascar. Our results confirm a relationship between plague anomalies and an increase in the intensity of ENSO events and precipitation. Conclusions/significance This work widens the understanding of how climate factors acting over different temporal scales can combine to drive local disease dynamics. Given the association of increasing ENSO strength and plague anomalies in Madagascar it may in future be possible to forecast plague outbreaks in Madagascar. The study gives insight into the complex and changing relationship between climate factors and plague in Madagascar. PMID

  12. Madagascar: A continental fragment of the paleo-super Dharwar craton of India

    NASA Astrophysics Data System (ADS)

    Agrawal, P. K.; Pandey, O. P.; Negi, J. G.

    1992-06-01

    The morphological kinship of Madagascar to its immediate neighbors on the west (African continent) and east (Indian subcontinent) during the Early and middle Cretaceous has been debated for the past two decades on the basis of available geologic, tectonic, and paleomagnetic information. Most of the paleoreconstructions of Madagascar have shown its attachment to the east African continent. We present magnetic satelite and gravity data, and morphological, geophysical, and geotectonic similarities to hypothesize that in the period before the breakup of Gondwana, Madagascar was a continental fragment of the paleo-super Dharwar craton of India.

  13. Africa and Madagascar during Permo-Triassic time: The evidence of the vertebrate faunas

    NASA Astrophysics Data System (ADS)

    Battail, Bernard; Beltan, Laurence; Dutuit, Jean-Michel

    Various sediments ranging from the Carboniferous to the Quaternary, including Permo Triassic beds, were deposited on the western margin of Madagascar. These can be compared with the sediments of the African Karoo. Comparative analysis of the vertebrate faunas from Madagascar and Africa, however, shows many differences and gives rise to questions which fall into three categories: phylogenetic relationship, faunal dispersal in Africa and Madagascar, and connection with other parts of Gondwanaland and Laurasia. The Late Permian and Early Triassic ichthyofaunas from Madagascar bear affinities with those of South Africa only at a generic or familial level, but the tetrapod faunas are completely different. The Late Triassic tetrapod fauna of Madagascar is represented only by scarce material; it differs from the South African fauna and can be better compared with that from North Africa. During the Late Permian and Early Triassic, Madagascar was obviously cut from the African continent by a marine barrier. The faunal relationships between Madagascar and North Africa in the Late Triassic can possibly be explained by migrations along the southern shore of the Tethys. Detailed consideration of all the possible connections of Africa and Madagascar with the rest of the world is beyond the scope of this paper. We found it useful, however, to give a few demonstrative examples of such connections in order to place the African and Malagasy faunas in a more global context. The Early Triassic ichthyofaunas from Madagascar are, in part, related to those of South Africa, but they display more affinities with Laurasian faunas from British Columbia, Greenland, and Spitsbergen. In addition, there are, apparently, close relationships between the trematosaurs from Madagascar and from Spitsbergen. The reptilian fauna from the Lystrosaurus zone of South Africa, which has no equivalent in Madagascar, is very closely related to the fauna from the Fremouw Formation of Antarctica. The reptilian

  14. Mangrove forest distributions and dynamics in Madagascar (1975-2005)

    USGS Publications Warehouse

    Giri, C.; Muhlhausen, J.

    2008-01-01

    Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of ?? one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ???2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km 2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%). ?? 2008 by MDPI.

  15. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar

    PubMed Central

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar. PMID:27101839

  16. Blood transcriptomes reveal novel parasitic zoonoses circulating in Madagascar's lemurs

    PubMed Central

    Hayes, Corinne E.; Williams, Cathy V.; Junge, Randall E.; Razafindramanana, Josia; Mass, Vanessa; Rakotondrainibe, Hajanirina; Yoder, Anne D.

    2016-01-01

    Zoonotic diseases are a looming threat to global populations, and nearly 75% of emerging infectious diseases can spread among wildlife, domestic animals and humans. A ‘One World, One Health’ perspective offers us an ideal framework for understanding and potentially mitigating the spread of zoonoses, and the island of Madagascar serves as a natural laboratory for conducting these studies. Rapid habitat degradation and climate change on the island are contributing to more frequent contact among humans, livestock and wildlife, increasing the potential for pathogen spillover events. Given Madagascar's long geographical isolation, coupled with recent and repeated introduction of agricultural and invasive species, it is likely that a number of circulating pathogens remain uncharacterized in lemur populations. Thus, it is imperative that new approaches be implemented for de novo pathogen discovery. To this end, we used non-targeted deep sequencing of blood transcriptomes from two species of critically endangered wild lemurs (Indri indri and Propithecus diadema) to characterize blood-borne pathogens. Our results show several undescribed vector-borne parasites circulating within lemurs, some of which may cause disease in wildlife, livestock and humans. We anticipate that advanced methods for de novo identification of unknown pathogens will have broad utility for characterizing other complex disease transmission systems. PMID:26814226

  17. Coevolution of Cyanogenic Bamboos and Bamboo Lemurs on Madagascar.

    PubMed

    Ballhorn, Daniel J; Rakotoarivelo, Fanny Patrika; Kautz, Stefanie

    2016-01-01

    Feeding strategies of specialist herbivores often originate from the coevolutionary arms race of plant defenses and counter-adaptations of herbivores. The interaction between bamboo lemurs and cyanogenic bamboos on Madagascar represents a unique system to study diffuse coevolutionary processes between mammalian herbivores and plant defenses. Bamboo lemurs have different degrees of dietary specialization while bamboos show different levels of chemical defense. In this study, we found variation in cyanogenic potential (HCNp) and nutritive characteristics among five sympatric bamboo species in the Ranomafana area, southeastern Madagascar. The HCNp ranged from 209±72 μmol cyanide*g-1 dwt in Cathariostachys madagascariensis to no cyanide in Bambusa madagascariensis. Among three sympatric bamboo lemur species, the greater bamboo lemur (Prolemur simus) has the narrowest food range as it almost exclusively feeds on the highly cyanogenic C. madagascariensis. Our data suggest that high HCNp is the derived state in bamboos. The ancestral state of lemurs is most likely "generalist" while the ancestral state of bamboo lemurs was determined as equivocal. Nevertheless, as recent bamboo lemurs comprise several "facultative specialists" and only one "obligate specialist" adaptive radiation due to increased flexibility is likely. We propose that escaping a strict food plant specialization enabled facultative specialist bamboo lemurs to inhabit diverse geographical areas.

  18. Could the Madagascar bloom be fertilized by Madagascan iron?

    NASA Astrophysics Data System (ADS)

    Srokosz, M. A.; Robinson, J.; McGrain, H.; Popova, E. E.; Yool, A.

    2015-08-01

    In the oligotrophic waters to the east of Madagascar, a large phytoplankton bloom is found to occur in late austral summer. This bloom is composed of nitrogen fixers and can cover up to ˜1% of the world's ocean surface area. Satellite observations show that its spatial structure is closely tied to the underlying mesoscale eddy field in the region. The causes of the bloom and its temporal behavior (timing of its initiation and termination) and spatial variability are poorly understood, in part due to a lack of in situ observations. Here an eddy resolving 1/12° resolution ocean general circulation model and Lagrangian particle tracking are used to examine the hypothesis that iron from sediments around Madagascar could be advected east by the mesoscale eddy field to fertilize the bloom, and that variability in advection could explain the significant interannual variability in the spatial extent of the bloom. The model results suggest that this is indeed possible and furthermore imply that the bloom could be triggered by warming of the mixed layer, leading to optimal conditions for nitrogen fixers to grow, while its termination could be due to iron exhaustion. It is found that advection of Madagascan iron could resupply the bloom region with this micronutrient in the period between the termination of one bloom and the initiation of the next in the following year.

  19. Summer climate of Madagascar and monsoon pulsing of its vortex

    NASA Astrophysics Data System (ADS)

    Jury, Mark R.

    2016-02-01

    This study analyzes the climate of Madagascar (12°-26°S, 43°-50°E) and its relation to the Indian Ocean during austral summer (Dec-Mar). Moisture converges onto a standing easterly wave and floods are prevalent in late summer. All-island daytime land temperatures exceed 38 °C in October and are ~4 °C above sea temperatures during summer. Analysis of thermally induced diurnal convection and circulation revealed inflow during the afternoon recirculated from the southeastern mountains and the warm Mozambique Channel. Summer rainfall follows latent and sensible heat flux during the first half of the day, and gains a surplus by evening via thunderstorms over the western plains. At the inter-annual time-scale, 2.3 years oscillations in all-island rainfall appear linked with the stratospheric quasi-biennial oscillation and corresponding 80 Dobson Unit ozone fluctuations during flood events. Wet spells at frequencies from 11-27 days derive from locally-formed tropical cyclones and NW-cloud bands. Flood case studies exhibit moisture recycling in the confluence zone between the sub-tropical anticyclone and the lee-side vortex. Hovmoller analysis of daily rainfall reinforces the concept of local generation and pulsing by cross-equatorial (Indian winter) monsoon flow rather than zonal atmospheric waves. Since the surface water budget is critical to agriculture in Madagascar, this study represents a further step to understand its meso-scale summer climate.

  20. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar.

    PubMed

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar.

  1. Coevolution of Cyanogenic Bamboos and Bamboo Lemurs on Madagascar

    PubMed Central

    Ballhorn, Daniel J.; Rakotoarivelo, Fanny Patrika; Kautz, Stefanie

    2016-01-01

    Feeding strategies of specialist herbivores often originate from the coevolutionary arms race of plant defenses and counter-adaptations of herbivores. The interaction between bamboo lemurs and cyanogenic bamboos on Madagascar represents a unique system to study diffuse coevolutionary processes between mammalian herbivores and plant defenses. Bamboo lemurs have different degrees of dietary specialization while bamboos show different levels of chemical defense. In this study, we found variation in cyanogenic potential (HCNp) and nutritive characteristics among five sympatric bamboo species in the Ranomafana area, southeastern Madagascar. The HCNp ranged from 209±72 μmol cyanide*g-1 dwt in Cathariostachys madagascariensis to no cyanide in Bambusa madagascariensis. Among three sympatric bamboo lemur species, the greater bamboo lemur (Prolemur simus) has the narrowest food range as it almost exclusively feeds on the highly cyanogenic C. madagascariensis. Our data suggest that high HCNp is the derived state in bamboos. The ancestral state of lemurs is most likely "generalist" while the ancestral state of bamboo lemurs was determined as equivocal. Nevertheless, as recent bamboo lemurs comprise several "facultative specialists" and only one "obligate specialist" adaptive radiation due to increased flexibility is likely. We propose that escaping a strict food plant specialization enabled facultative specialist bamboo lemurs to inhabit diverse geographical areas. PMID:27532127

  2. Late Miocene uplift and doming of Madagascar: topographic implications

    NASA Astrophysics Data System (ADS)

    Delaunay, Antoine; Robin, Cecile; Guillocheau, François; Dall'Asta, Massimo; Calves, Gérôme

    2016-04-01

    Madagascar is an Archean to Neoproterozoic continental crust surrounded by transform, oblique and divergent margins: the oblique Morondava Basin to the west, pounded by the Davie Fracture Zone, and to the north, the divergent Mahajanga (Majunga) Basin connected to the Somali Oceanic Basin. This 1600 km long island is a high axial plateau with elevations from 1200 to 1800m. The top of the plateau corresponds to weathered planation surfaces (etchplains), bounded by more or less high scarps. We here present geological arguments for the age and the timing of the Madagascar Plateau. This analysis is based on a double, coupled analysis of the onshore geomorphology (stepped planation surfaces) and the offshore margin stratigraphy (seismic stratigraphy and wells). The geomorphological analysis is based on a characterization, a mapping and dating of stepped planation surfaces (mantled to stripped etchplains, pediments to pediplains). The dating is based on their geometrical relationships with dated magmatic rocks. The difference of elevation between two planation surfaces (corresponding to local base level) provides a proxy of the uplift. The sequence stratigraphic analysis is based on a biostratigraphic reevaluation of 4 industrial wells (foraminifers and nannofossils on cuttings). Uplift periods are characterized by (1) seaward tiltings of the margins overlain by planar reflectors, (2) forced regression wedges and (3) upstream erosions of older sediments recorded by fauna/flora reworking. (1) During Paleocene to Middle Miocene times (66 to 13 Ma), Madagascar is a quite flat low elevation domain with remnants of an oldest pre-Madagascar Trap (90 Ma) surface. This low relief is highly weathered with growth of numerous lateritic profiles and surrounded by large carbonate platforms with no siliciclastic sands influx. (2) The Late Miocene is the paroxysm of uplift with (1) a tilting of the margin (Morondova), (2) an increase of the siliciclastic sand flux since middle Miocene

  3. Madagascar Flatidae (Hemiptera, Fulgoromorpha): state-of-the-art and research challenges

    PubMed Central

    Świerczewski, Dariusz; Stroiński, Adam

    2013-01-01

    Abstract The paper provides a historical review of the research on Flatidae in Madagascar and indicates future prospects. While the first two species of Madagascar Flatidae were described by Guérin-Méneville (1844), it was Signoret (1860) who made the first real attempt to enhance our knowledge of the Hemiptera fauna of Madagascar by describing several additional species. Over the following century and a half, several investigators have turned their attention to this group of insects, with the final number of species recorded for the island reaching 79. Despite this long history of research, it is evident that much still remains to be done. Detailed taxonomic research will allow the natural history of Madagascar and changes in the biological diversity of its endemic ecosystems to be better understood. This paper should be considered as an introduction to a complex study on the systematics and phylogeny of worldwide Flatidae planthoppers. PMID:24039526

  4. A review of mosquitoes associated with Rift Valley fever virus in Madagascar.

    PubMed

    Tantely, Luciano M; Boyer, Sébastien; Fontenille, Didier

    2015-04-01

    Rift Valley fever (RVF) is a viral zoonotic disease occurring throughout Africa, the Arabian Peninsula, and Madagascar. The disease is caused by a Phlebovirus (RVF virus [RVFV]) transmitted to vertebrate hosts through the bite of infected mosquitoes. In Madagascar, the first RVFV circulation was reported in 1979 based on detection in mosquitoes but without epidemic episode. Subsequently, two outbreaks occurred: the first along the east coast and in the central highlands in 1990 and 1991 and the most recent along the northern and eastern coasts and in the central highlands in 2008 and 2009. Despite the presence of 24 mosquitoes species potentially associated with RVFV transmission in Madagascar, little associated entomological information is available. In this review, we list the RVFV vector, Culex antennatus, as well as other taxa as candidate vector species. We discuss risk factors from an entomological perspective for the re-emergence of RVF in Madagascar.

  5. Miocene Shark and Batoid Fauna from Nosy Makamby (Mahajanga Basin, Northwestern Madagascar).

    PubMed

    Andrianavalona, Tsiory H; Ramihangihajason, Tolotra N; Rasoamiaramanana, Armand; Ward, David J; Ali, Jason R; Samonds, Karen E

    2015-01-01

    Madagascar is well known for producing exceptional fossils. However, the record for selachians remains relatively poorly known. Paleontological reconnaissance on the island of Nosy Makamby, off northwest Madagascar, has produced a previously undescribed assemblage of Miocene fossils. Based on isolated teeth, ten taxonomic groups are identified: Otodus, Carcharhinus, Galeocerdo, Rhizoprionodon, Sphyrna, Hemipristis, Squatina, Rostroraja, Himantura and Myliobatidae. Six are newly described from Madagascar for the Cenozoic (Galeocerdo, Rhizoprionodon, Sphyrna, Squatina, Rostroraja and Himantura). In association with these specimens, remains of both invertebrates (e.g., corals, gastropods, bivalves) and vertebrates (e.g., bony fish, turtles, crocodylians, and sirenian mammals) were also recovered. The sedimentary facies are highly suggestive of a near-shore/coastal plain depositional environment. This faunal association shares similarities to contemporaneous sites reported from North America and Europe and gives a glimpse into the paleoenvironment of Madagascar's Miocene, suggesting that this region was warm, tropical shallow-water marine.

  6. Genetic Diversity of the Ring-Tailed Lemur (Lemur catta) in South-Central Madagascar.

    PubMed

    Clarke, Tara A; Gray, Olivia; Gould, Lisa; Burrell, Andrew S

    2015-01-01

    Madagascar's lemurs, now deemed the most endangered group of mammals, represent the highest primate conservation priority in the world. Due to anthropogenic disturbances, an estimated 10% of Malagasy forest cover remains. The endangered Lemur catta is endemic to the southern regions of Madagascar and now occupies primarily fragmented forest habitats. We examined the influence of habitat fragmentation and isolation on the genetic diversity of L. catta across 3 different forest fragments in south-central Madagascar. Our analysis revealed moderate levels of genetic diversity. Genetic differentiation among the sites ranged from 0.05 to 0.11. These data suggest that the L. catta populations within south-central Madagascar have not yet lost significant genetic variation. However, due to ongoing anthropogenic threats faced by ring-tailed lemurs, continued conservation and research initiatives are imperative for long-term viability of the species.

  7. A juvenile subfossil crocodylian from Anjohibe Cave, Northwestern Madagascar

    PubMed Central

    Samonds, Karen E.

    2016-01-01

    Madagascar’s subfossil record preserves a diverse community of animals including elephant birds, pygmy hippopotamus, giant lemurs, turtles, crocodiles, bats, rodents, and carnivorans. These fossil accumulations give us a window into the island’s past from 80,000 years ago to a mere few hundred years ago, recording the extinction of some groups and the persistence of others. The crocodylian subfossil record is limited to two taxa, Voay robustus and Crocodylus niloticus, found at sites distributed throughout the island. V. robustus is extinct while C. niloticus is still found on the island today, but whether these two species overlapped temporally, or if Voay was driven to extinction by competing with Crocodylus remains unknown. While their size and presumed behavior was similar to each other, nearly nothing is known about the growth and development of Voay, as the overwhelming majority of fossil specimens represent mature adult individuals. Here we describe a nearly complete juvenile crocodylian specimen from Anjohibe Cave, northwestern Madagascar. The specimen is referred to Crocodylus based on the presence of caviconchal recesses on the medial wall of the maxillae, and to C. niloticus based on the presence of an oval shaped internal choana, lack of rostral ornamentation and a long narrow snout. However, as there are currently no described juvenile specimens of Voay robustus, it is important to recognize that some of the defining characteristics of that genus may have changed through ontogeny. Elements include a nearly complete skull and many postcranial elements (cervical, thoracic, sacral, and caudal vertebrae, pectoral elements, pelvic elements, forelimb and hindlimb elements, osteoderms). Crocodylus niloticus currently inhabits Madagascar but is locally extinct from this particular region; radiometric dating indicates an age of ∼460–310 years before present (BP). This specimen clearly represents a juvenile based on the extremely small size and open

  8. New and bioactive natural products isolated from madagascar plants and marine organisms.

    PubMed

    Hou, Y; Harinantenaina, L

    2010-01-01

    Madagascar, the world's fourth biggest island has an unique biodiversity. The interest on the phytochemical investigation of Malagasy plants and marine natural products started from the isolation of the potent anti-cancerous bisindole alkaloids: vinblastine and vincristine. In this paper, works published in the last two decades (1991-2009) on 270 new natural products isolated from Madagascar higher plants, liverworts and marine organisms are reviewed. Several results on the bioassays of the isolated new natural products have been reported.

  9. Review of West Nile virus circulation and outbreak risk in Madagascar: Entomological and ornithological perspectives

    PubMed Central

    Tantely, Michaël Luciano; Goodman, Steven M.; Rakotondranaivo, Tsirinaina; Boyer, Sébastien

    2016-01-01

    West Nile fever (WNF) is a zoonotic disease, occurring nearly globally. In Madagascar, West Nile virus (WNV) was first detected in 1978 from wild birds and the virus is currently distributed across the island, but no epidemic or epizootic period has been recorded. One fatal human case of WNV infection was reported in 2011, suggesting a “tip of the iceberg” phenomenon of a possible WNF epidemic/epizootic on the island. The main objective of this literature-based survey is to review patterns of WNV circulation in Madagascar from the entomological and ornithological points of view. Among the 235 mosquito species described from Madagascar, 29 species are widely associated with WNV infection; 16 of them are found naturally infected with WNV on the island and categorized into major, candidate, and potential vectors of WNV according to their vector capacity. This study upholds the hypothesis that WNV enzooticity is independent of annual movements of migratory birds passing through Madagascar. Moreover, the lack of regular migratory bird flux between Africa and Madagascar would reduce the probability of transmission and the subsequent reintroduction of the virus into locally occurring mosquito species. Given that Palearctic migratory birds are strongly implicated in the transmission of WNV, we highlight notable differences in the movements and species diversity of these birds in Madagascar as compared to eastern and northern Africa. Risk factors from this two-pronged approach are presented for the emergence of WNF outbreak. PMID:27849515

  10. Healing words: becoming a spirit-host in Madagascar.

    PubMed

    Mack, John

    2011-08-01

    In discussion of healing processes in sub-Saharan Africa, emphasis is characteristically placed on the role of performance. Yet in spirit mediumship, speech is also an important element in therapeutic practices. In Madagascar, the spirits (tromba) are often of exotic origins (frequently in time as well as space) and the language used is likewise exotic. A complex of techniques of enchantment is employed: amongst them, music, changes of dress, the burning of perfumes and incense, rum, putting matches in the mouth, or the use of herbal medicines. Sometimes artefacts, such as - in the case discussed - a large model ship, are employed. Although the setting is shrine-like, the techniques are at once both dynamic and eclectic, collapsing time and space into a single embodied moment when the spirit speaks through the vehicle of the medium. Such 'spirit-speech' is itself empowered and empowering, cathartic and curative.

  11. Community level risk factors for maternal mortality in Madagascar.

    PubMed

    Hernandez, Julio C; Moser, Christine M

    2013-12-01

    This paper explores the effect of risk and socioeconomic factors on maternal mortality at the community level in Madagascar using a unique, nationwide panel of communes (i.e., counties). Previous work in this area uses individual or cross-country data to study maternal mortality, however, studying maternal mortality at the community level is imperative because this is the level at which most policy is implemented. The results show that longer travel time from the community to the hospital leads to a high level of maternal mortality. The findings suggest that improvement to transportation systems and access to hospitals with surgery rooms are needed to deal with obstetric complications and reduce maternal mortality.

  12. View of Africa and Madagascar from the Apollo 17 spacecraft

    NASA Image and Video Library

    1972-12-09

    AS17-148-22717 (7 Dec. 1972) --- This view of a portion of Earth was taken from the Apollo 17 spacecraft following trans-lunar insertion during the final lunar landing mission in NASA's Apollo Program. The visible land mass is the southern two-thirds of the African continent, with Madagascar at right. A portion of Antarctica is visible at bottom frame. Onboard the Apollo 17 spacecraft were astronauts Eugene A. Cernan, commander; Ronald E. Evans, command module pilot; and Harrison H. Schmitt, lunar module pilot. While astronauts Cernan and Schmitt descended in the Lunar Module (LM) "Challenger" to explore the Hadley-Apennine region of the moon, astronaut Evans remained with the Command and Service Modules (CSM) "America" in lunar orbit.

  13. Terrestrial runoff influences white syndrome prevalence in SW Madagascar.

    PubMed

    Sheridan, C; Baele, J M; Kushmaro, A; Fréjaville, Y; Eeckhaut, I

    2014-10-01

    Terrestrial runoff and sedimentation have been implicated in a variety of impacts on scleractinian corals. However, despite accumulating evidence, little work has been done to investigate their influence on coral disease development. This study examined the role that river runoff and the associated sedimentation could play in affecting the prevalence of the coral disease "white syndrome" in SW Madagascar. Corals from reefs affected by river discharge and terrestrial sediments were more affected by white syndrome than reefs located far from any source of terrestrial runoff. Terrestrial runoff-affected reefs also displayed a wider diversity of coral species affected by this disease. While much evidence has been pointing in the direction of indirect effects of such runoff on coral disease development, our data corroborates earlier suggestions that pathogens are present within the sediments. As such, sediments released on reefs through river discharge could act as reservoirs of coral pathogens.

  14. Capture, Movement, Trade, and Consumption of Mammals in Madagascar

    PubMed Central

    Reuter, Kim E.; Randell, Haley; Wills, Abigail R.; Janvier, Totozafy Eric; Belalahy, Tertius Rodriguez; Sewall, Brent J.

    2016-01-01

    Wild meat trade constitutes a threat to many animal species. Understanding the commodity chain of wild animals (hunting, transportation, trade, consumption) can help target conservation initiatives. Wild meat commodity chain research has focused on the formal trade and less on informal enterprises, although informal enterprises contribute to a large portion of the wild meat trade in sub-Saharan Africa. We aimed to provide a more comprehensive understanding of the formal and informal components of these commodity chains by focusing on the mammalian wild meat trade in Madagascar. Our objectives were to: (1) identify hunting strategies used to capture different wild mammals; (2) analyze patterns of movement of wild meat from the capture location to the final consumer; (3) examine wild meat prices, volumes, and venues of sale; and (4) estimate the volume of wild meat consumption. Data were collected in May-August 2013 using semi-structured interviews with consumers (n = 1343 households, 21 towns), meat-sellers (n = 520 restaurants, open-air markets stalls, and supermarkets, 9 towns), and drivers of inter-city transit vehicles (n = 61, 5 towns). We found that: (1) a wide range of hunting methods were used, though prevalence of use differed by animal group; (2) wild meat was transported distances of up to 166 km to consumers, though some animal groups were hunted locally (<10 km) in rural areas; (3) most wild meat was procured from free sources (hunting, gifts), though urban respondents who consumed bats and wild pigs were more likely to purchase those meats; and (4) wild meat was consumed at lower rates than domestic meat, though urban respondents consumed wild meat twice as much per year compared to rural respondents. Apart from the hunting stage, the consumption and trade of wild meat in Madagascar is also likely more formalized than previously thought. PMID:26926987

  15. Recent emergence of new variants of Yersinia pestis in Madagascar.

    PubMed

    Guiyoule, A; Rasoamanana, B; Buchrieser, C; Michel, P; Chanteau, S; Carniel, E

    1997-11-01

    Yersinia pestis, the causative agent of plague, has been responsible for at least three pandemics. During the last pandemic, which started in Hong Kong in 1894, the microorganism colonized new, previously unscathed geographical areas where it has become well established. The aim of this longitudinal study was to investigate the genetic stability of Y. pestis strains introduced into a new environment just under a century ago and to follow the epidemiology of any new genetic variant detected. In the present study, 187 strains of Y. pestis isolated between 1939 and 1996 from different regions of Madagascar and responsible mainly for human cases of bubonic and pneumonic plague were studied. Our principal genotyping method was rRNA gene profiling (ribotyping), which has previously been shown to be an effective scheme for typing Y. pestis strains of different geographical origins. We report that all studied Y. pestis strains isolated in Madagascar before 1982 were of classical ribotype B, the ribotype attributed to the Y. pestis clone that spread around the world during the third pandemic. In 1982, 1983, and 1994, strains with new ribotypes, designated R, Q, and T, respectively, were isolated on the high-plateau region of the island. Analysis of other genotypic traits such as the NotI genomic restriction profiles and the EcoRV plasmid restriction profiles revealed that the new variants could also be distinguished by specific genomic and/or plasmid profiles. A follow-up of these new variants indicated that strains of ribotypes Q and R have become well established in their ecosystem and have a tendency to spread to new geographical areas and supplant the original classical strain.

  16. Capture, Movement, Trade, and Consumption of Mammals in Madagascar.

    PubMed

    Reuter, Kim E; Randell, Haley; Wills, Abigail R; Janvier, Totozafy Eric; Belalahy, Tertius Rodriguez; Sewall, Brent J

    2016-01-01

    Wild meat trade constitutes a threat to many animal species. Understanding the commodity chain of wild animals (hunting, transportation, trade, consumption) can help target conservation initiatives. Wild meat commodity chain research has focused on the formal trade and less on informal enterprises, although informal enterprises contribute to a large portion of the wild meat trade in sub-Saharan Africa. We aimed to provide a more comprehensive understanding of the formal and informal components of these commodity chains by focusing on the mammalian wild meat trade in Madagascar. Our objectives were to: (1) identify hunting strategies used to capture different wild mammals; (2) analyze patterns of movement of wild meat from the capture location to the final consumer; (3) examine wild meat prices, volumes, and venues of sale; and (4) estimate the volume of wild meat consumption. Data were collected in May-August 2013 using semi-structured interviews with consumers (n = 1343 households, 21 towns), meat-sellers (n = 520 restaurants, open-air markets stalls, and supermarkets, 9 towns), and drivers of inter-city transit vehicles (n = 61, 5 towns). We found that: (1) a wide range of hunting methods were used, though prevalence of use differed by animal group; (2) wild meat was transported distances of up to 166 km to consumers, though some animal groups were hunted locally (<10 km) in rural areas; (3) most wild meat was procured from free sources (hunting, gifts), though urban respondents who consumed bats and wild pigs were more likely to purchase those meats; and (4) wild meat was consumed at lower rates than domestic meat, though urban respondents consumed wild meat twice as much per year compared to rural respondents. Apart from the hunting stage, the consumption and trade of wild meat in Madagascar is also likely more formalized than previously thought.

  17. Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles.

    PubMed

    Brown, Jason L; Sillero, Neftali; Glaw, Frank; Bora, Parfait; Vieites, David R; Vences, Miguel

    2016-01-01

    Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800-1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount of

  18. Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles

    PubMed Central

    Brown, Jason L.; Sillero, Neftali; Glaw, Frank; Bora, Parfait; Vieites, David R.; Vences, Miguel

    2016-01-01

    Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800–1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount

  19. [Water and environment in the Southwest of Madagascar].

    PubMed

    Razanamparany, L

    1993-04-01

    The dry and arid southwest region of Madagascar is not a desert but resembles the Sahel region of West Africa. The chronic water deficit is aggravated by the heat and constant winds that accelerate evapotranspiration on the permeable soils. The dryness occurs because the southwest region lies outside the main pluviogenic systems. Erosion occurs at all seasons. In the winter the sun and winds are the main causes, while the rare storms are more conducive to run-off and to erosion than to absorption. The acute water shortage in the southwest has prompted hydrogeologic research and well-drilling, but the high salt content of the water and other impurities will be a limiting factor for development of the area. The population of the southwest is extremely mobile. Human settlements are concentrated in the valleys and depressions and along major roads. Customary rights to land under the control of the traditional chiefs regulate tenure in most areas. But especially in the river bottoms, the coming of cash crops cultivated with modern equipment has resulted in significant erosion which has aggravated ecological problems. Accelerating soil degradation has led peasants to extend their lands under cultivation to the detriment of forest cover. Cattle herding remains the principal economic activity in the southwest. Herding has progressed from nomadism to pastoralism, but it remains a sign of power and wealth. Transhumance is the strategy of herders faced with shortages of water and pasturage, demographic pressure, and environmental degradation. Raising of sheep and goats constitutes a supplemental food source, medium of exchange, and form of savings. But angora goats graze on everything in their path, devastating their surrounds. Fear of cattle thefts militates against efforts to improve the quality of the stock. The various problems together have prompted a wasteful exploitation of the forest resources. Development strategies for the area explored by the government have all

  20. Lemur traits and Madagascar ecology: coping with an island environment.

    PubMed

    Wright, P C

    1999-01-01

    The last decade's lemur research includes successes in discovering new living and extinct species and learning about the distribution, biogeography, physiology, behavior, and ecology of previously little-studied species. In addition, in both the dry forest and rain forest, long-term studies of lemur demography, life history, and reproduction, have been completed in conjunction with data on tree productivity, phenology, and climate. Lemurs contrast with anthropoids in several behavioral features, including female dominance, targeted female-female aggression, lack of sexual dimorphism regardless of mating system, sperm competition coupled with male-male aggression, high infant mortality, cathemerality, and strict seasonal breeding. Hypotheses to explain these traits include the "energy conservation hypothesis" (ECH) suggesting that harsh and unpredictable climate factors on the island of Madagascar have affected the evolution of female dominance, and the "evolutionary disequilibrium hypotheses" (EVDH) suggesting that the recent megafauna extinctions have influenced lemurs to become diurnal. These hypotheses are compared and contrasted in light of recent empirical data on climate, subfossils, and lemur behavior. New data on life histories of the rain forest lemurs at Ranomafana National Park give further support to the ECH. Birth seasons are synchronized within each species, but there is a 6-month distribution of births among species. Gestation and lactation lengths vary among sympatric lemurs, but all lemur species in the rain forest wean in synchrony at the season most likely to have abundant resources. Across-species weaning synchrony seen in Ranomafana corroborates data from the dry forest that late lactation and weaning is the life history event that is the primary focus of the annual schedule. Lemur adaptations may assure maximum offspring survival in this environment with an unpredictable food supply and heavy predation. In conclusion, a more comprehensive

  1. Sentinel surveillance system for early outbreak detection in Madagascar

    PubMed Central

    2010-01-01

    Background Following the outbreak of chikungunya in the Indian Ocean, the Ministry of Health directed the necessary development of an early outbreak detection system. A disease surveillance team including the Institut Pasteur in Madagascar (IPM) was organized to establish a sentinel syndromic-based surveillance system. The system, which was set up in March 2007, transmits patient data on a daily basis from the various voluntary general practitioners throughout the six provinces of the country to the IPM. We describe the challenges and steps involved in developing a sentinel surveillance system and the well-timed information it provides for improving public health decision-making. Methods Surveillance was based on data collected from sentinel general practitioners (SGP). The SGPs report the sex, age, visit date and time, and symptoms of each new patient weekly, using forms addressed to the management team. However, the system is original in that SGPs also report data at least once a day, from Monday to Friday (number of fever cases, rapid test confirmed malaria, influenza, arboviral syndromes or diarrhoeal disease), by cellular telephone (encrypted message SMS). Information can also be validated by the management team, by mobile phone. This data transmission costs 120 ariary per day, less than US$1 per month. Results In 2008, the sentinel surveillance system included 13 health centers, and identified 5 outbreaks. Of the 218,849 visits to SGPs, 12.2% were related to fever syndromes. Of these 26,669 fever cases, 12.3% were related to Dengue-like fever, 11.1% to Influenza-like illness and 9.7% to malaria cases confirmed by a specific rapid diagnostic test. Conclusion The sentinel surveillance system represents the first nationwide real-time-like surveillance system ever established in Madagascar. Our findings should encourage other African countries to develop their own syndromic surveillance systems. Prompt detection of an outbreak of infectious disease may lead to

  2. Education and Training in Madagascar: Toward a Policy Agenda for Economic Growth and Poverty Reduction. A World Bank Country Study.

    ERIC Educational Resources Information Center

    World Bank, Washington, DC.

    Madagascar is a poor, primarily rural country in which three-quarters of the population has subsisted below the poverty line for at least two decades. In view of the important role of education in the government's poverty reduction agenda, this report documents the current status of educational development in Madagascar and the key constraints on…

  3. Education and Training in Madagascar: Toward a Policy Agenda for Economic Growth and Poverty Reduction. A World Bank Country Study.

    ERIC Educational Resources Information Center

    World Bank, Washington, DC.

    Madagascar is a poor, primarily rural country in which three-quarters of the population has subsisted below the poverty line for at least two decades. In view of the important role of education in the government's poverty reduction agenda, this report documents the current status of educational development in Madagascar and the key constraints on…

  4. Detection in and circulation of Bluetongue virus among domestic ruminants in Madagascar.

    PubMed

    Andriamandimby, Soa Fy; Viarouge, Cyril; Ravalohery, Jean-Pierre; Reynes, Jean-Marc; Sailleau, Corinne; Tantely, Michael Luciano; Elissa, Nohal; Cardinale, Eric; Sall, Amadou Alpha; Zientara, Stephan; Heraud, Jean-Michel

    2015-04-17

    So far, no published data was available concerning the circulation of Bluetongue virus (BTV) in Madagascar. During a survey on Rift Valley Fever, we were able to detect a virus belonging to BTV. Therefore, we conducted a study aiming at characterizing molecularly the BTV isolated and assess the importance of circulation of BTV in Madagascar. A total of 4393 sera from ruminants selected randomly by stratification and sampled in 30 districts of Madagascar were tested for BTV. Moreover, 175 cattle were followed during 11 months. Phylogenetic analyses were performed from virus isolated from unfed pools of mosquitoes. Overall, the estimated mean seroprevalence of infection at the national level was 95.9% (95% CI: [95.2-96.5]) in cattle and 83.7% (95% CI: [81.4-85.9]) in small ruminants. Estimation of incidence rate was 54 per 100 cattle-years assuming that the incidence rate is constant all year along. Phylogenetic analyses revealed that BTV detected belong to serotype 2. In conclusion, our results showed that BTV is endemic in Madagascar and highly prevalent among cattle. In our study we did not work on the vector involved in transmission of BTV in cattle. Thus, research should be conducted to better describe epidemiology of BTV in Madagascar including vectors and assess economic impact of the disease associated to BTV infections.

  5. Why is Madagascar special? The extraordinarily slow evolution of pelican spiders (Araneae, Archaeidae).

    PubMed

    Wood, Hannah M; Gillespie, Rosemary G; Griswold, Charles E; Wainwright, Peter C

    2015-02-01

    Although Madagascar is an ancient fragment of Gondwana, the majority of taxa studied thus far appear to have reached the island through dispersal from Cenozoic times. Ancient lineages may have experienced a different history compared to more recent Cenozoic arrivals, as such lineages would have encountered geoclimatic shifts over an extended time period. The motivation for this study was to unravel the signature of diversification in an ancient lineage by comparing an area known for major geoclimatic upheavals (Madagascar) versus other areas where the environment has been relatively stable. Archaeid spiders are an ancient paleoendemic group with unusual predatory behaviors and spectacular trophic morphology that likely have been on Madagascar since its isolation. We examined disparities between Madagascan archaeids and their non-Madagascan relatives regarding timing of divergence, rates of trait evolution, and distribution patterns. Results reveal an increased rate of adaptive trait diversification in Madagascan archaeids. Furthermore, geoclimatic events in Madagascar over long periods of time may have facilitated high species richness due to montane refugia and stability, rainforest refugia, and also ecogeographic shifts, allowing for the accumulation of adaptive traits. This research suggests that time alone, coupled with more ancient geoclimatic events allowed for the different patterns in Madagascar. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  6. The odd man out in Sub-Saharan Africa: understanding the tobacco use prevalence in Madagascar

    PubMed Central

    2013-01-01

    Background The tobacco industry has globalized and tobacco use continues to increase in low- and middle-income countries. Yet, the data and research to inform policy initiatives for addressing this phenomenon is sparse. This study aims to estimate the prevalence of adult tobacco use in 17 Sub-Saharan Africa (SSA) countries, and to identify key factors associated with adult tobacco consumption choices (smoked, smokeless tobacco and dual use) in Madagascar. Methods We used Demographic Health Survey for estimating tobacco use prevalence among adults in SSA. A multinomial logistic regression model was used to identify key determinants of adult tobacco consumption choices in Madagascar. Results While differences in tobacco use exist in SSA, Madagascar has exceptionally higher prevalence rates (48.9% of males; 10.3% of females). The regression analyses showed complexity of tobacco use in Madagascar and identified age, education, wealth, employment, marriage, religion and place of residence as factors significantly associated with the choice of tobacco use among males, while age, wealth, and employment were significantly associated with that of females. The effects, however, differ across the three choices of tobacco use compared to non-use. Conclusions Tobacco use in Madagascar was higher than the other 16 SSA countries. Although the government continues to enact policies to address the problem, there is a need for effective implementation and enforcement. There is also the need for health education to modify social norms and denormalize tobacco use. PMID:24044737

  7. Presence of the amphibian chytrid fungus Batrachochytrium dendrobatidis in native amphibians exported from Madagascar.

    PubMed

    Kolby, Jonathan E

    2014-01-01

    The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented.

  8. Presence of the Amphibian Chytrid Fungus Batrachochytrium dendrobatidis in Native Amphibians Exported from Madagascar

    PubMed Central

    Kolby, Jonathan E.

    2014-01-01

    The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented. PMID:24599336

  9. Provenance and tectonic significance of the Palaeoproterozoic metasedimentary successions of central and nothern Madagascar

    USGS Publications Warehouse

    De Waele, B.; Thomas, Ronald J.; Macey, P.H.; Horstwood, M.S.A.; Tucker, R.D.; Pitfield, P.E.J.; Schofield, D.I.; Goodenough, K.M.; Bauer, W.; Key, R.M.; Potter, C.J.; Armstrong, R.A.; Miller, J.A.; Randriamananjara, T.; Ralison, V.; Rafahatelo, J.-M.; Rabarimanana, M.; Bejoma, M.

    2011-01-01

    New detrital zircon U–Pb age data obtained from various quartzite units of three spatially separated supracrustal packages in central and northern Madagascar, show that these units were deposited between 1.8 and 0.8 Ga and have similar aged provenances. The distribution of detrital zircon ages indicates an overwhelming contribution of sources with ages between 2.5 and 1.8 Ga. Possible source rocks with an age of 2.5 Ga are present in abundance in the crustal segments (Antananarivo, Antongil and Masora Domains) either side of a purported Neoproterozoic suture ("Betsimisaraka Suture Zone"). Recently, possible source rocks for the 1.8 Ga age peak have been recognised in southern Madagascar. All three supracrustal successions, as well as the Archaean blocks onto which they were emplaced, are intruded by mid-Neoproterozoic magmatic suites placing a minimum age on their deposition. The similarities in detrital pattern, maximum and minimum age of deposition in the three successions, lend some support to a model in which all of Madagascar's Archaean blocks form a coherent crustal entity (the Greater Dharwar Craton), rather than an amalgamate of disparate crustal blocks brought together only during Neoproterozoic convergence. However, potential source terranes exist outside Madagascar and on either side of the Neoproterozoic sutures, so that a model including a Neoproterozoic suture in Madagascar cannot be dispelled outright.

  10. Poverty Reduction and Millennium Development Goals: Recognizing Population, Health, and Environment Linkages in Rural Madagascar

    PubMed Central

    Gaffikin, Lynne; Ashley, Jeffrey; Blumenthal, Paul D.

    2007-01-01

    The Millennium Development Goals (MDGs), committed to by all 191 United Nations member states, are rooted in the concept of sustainable development. Although 2007 (midway) reports indicated that programs are under way, unfortunately many countries are unlikely to reach their goals by 2015 due to high levels of poverty. Madagascar is one such example, although some gains are being made. Attempts of this island nation to achieve its MDGs, expressed most recently in the form of a Madagascar Action Plan, are notable in their emphasis on (1) conserving the country's natural resource base, (2) the effect of demographic trends on development, and (3) the importance of health as a prerequisite for development. Leadership in the country's struggle for economic growth comes from the president of the Republic, in part, through his “Madagascar Naturally” vision as well as his commitment to universal access to family planning, among other health and development interventions. However, for resource-limited countries, such as Madagascar, to get or stay “on track” to achieving the MDGs will require support from many sides. “Madagascar cannot do it alone and should not do it alone.” This position is inherent in the eighth MDG: “Develop a global partnership for development.” Apparently, it takes a village after all – a global one. PMID:18311367

  11. Amphibian Chytrid Fungus in Madagascar neither Shows Widespread Presence nor Signs of Certain Establishment.

    PubMed

    Kolby, Jonathan E; Skerratt, Lee F

    2015-01-01

    The global spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) is associated with amphibian mass mortality, population decline, and extinction. Over the past decade, concern has been expressed for the potential introduction of Bd to Madagascar, a global hotspot of amphibian biodiversity. Following years without detection, widespread Bd presence in Madagascar has now been reported (Bletz et al. 2015a), raising international conservation concern. Before reacting to this finding with a significant management response, the accuracy and context of the data warrant cautious review. Re-examination of a 10-year dataset together with results from more recent surveillance (Kolby et al. 2015) does not yet demonstrate widespread Bd presence. Detection of Bd at "positive" locations in Madagascar has been inconsistent for unknown reasons. Whether Bd is established in Madagascar (i.e. populations are self-sustaining) or instead requires continued introduction to persist also remains uncertain. The deployment of emergency conservation rescue initiatives is expected to target areas where the distribution of Bd and the risk of chytridiomycosis endangering amphibians is believed to overlap. Thus, erroneous description of Bd presence would misdirect limited conservation resources. Standardized surveillance and confirmatory surveys are now imperative to reliably characterize the distribution, potential spread, virulence and overall risk of Bd to amphibians in Madagascar.

  12. Drivers of Rift Valley fever epidemics in Madagascar

    PubMed Central

    Lancelot, Renaud; Béral, Marina; Rakotoharinome, Vincent Michel; Andriamandimby, Soa-Fy; Héraud, Jean-Michel; Coste, Caroline; Apolloni, Andrea; Squarzoni-Diaw, Cécile; de La Rocque, Stéphane; Wint, G. R. William; Cardinale, Eric

    2017-01-01

    Rift Valley fever (RVF) is a vector-borne viral disease widespread in Africa. The primary cycle involves mosquitoes and wild and domestic ruminant hosts. Humans are usually contaminated after contact with infected ruminants. As many environmental, agricultural, epidemiological, and anthropogenic factors are implicated in RVF spread, the multidisciplinary One Health approach was needed to identify the drivers of RVF epidemics in Madagascar. We examined the environmental patterns associated with these epidemics, comparing human and ruminant serological data with environmental and cattle-trade data. In contrast to East Africa, environmental drivers did not trigger the epidemics: They only modulated local Rift Valley fever virus (RVFV) transmission in ruminants. Instead, RVFV was introduced through ruminant trade and subsequent movement of cattle between trade hubs caused its long-distance spread within the country. Contact with cattle brought in from infected districts was associated with higher infection risk in slaughterhouse workers. The finding that anthropogenic rather than environmental factors are the main drivers of RVF infection in humans can be used to design better prevention and early detection in the case of RVF resurgence in the region. PMID:28096420

  13. Schooling, marriage, and age at first birth in Madagascar.

    PubMed

    Glick, Peter; Handy, Christopher; Sahn, David E

    2015-01-01

    The low school attainment, early marriage, and low age at first birth of females are major policy concerns in less developed countries. This study jointly estimated the determinants of educational attainment, marriage age, and age at first birth among females aged 12-25 in Madagascar, explicitly accounting for the endogeneities that arose from modelling these related outcomes simultaneously. An additional year of schooling results in a delay to marriage of 1.5 years and marrying 1 year later delays age at first birth by 0.5 years. Parents' education and wealth also have important effects on schooling, marriage, and age at first birth, with a woman's first birth being delayed by 0.75 years if her mother had 4 additional years of schooling. Overall, our results provide rigorous evidence for the critical role of education-both individual women's own and that of their parents-in delaying the marriage and fertility of young women.

  14. A new species of Ptychochromis from southeastern Madagascar (Teleostei: Cichlidae).

    PubMed

    Martinez, Christopher M; Arroyave, Jairo; Sparks, John S

    2015-11-17

    We describe a new species in the endemic Malagasy cichlid genus Ptychochromis. Ptychochromis mainty, new species, is known from four individuals, all collected in the Fort Dauphin region of southeastern Madagascar, and shares a palatine morphology (eastern-type palatine) with other eastern congeners. Ptychochromis mainty is distinguished from all congeners by a nearly uniform dark brown to black pigmentation pattern in preservation and by the presence of a relatively continuous and expansive black longitudinal midlateral blotch in life, extending from the posterior margin of the opercle to the caudal peduncle. The new species is further distinguished from other eastern Ptychochromis species by having minimal or no overlap of the first supraneural with the dorsoposterior region of the supraoccipital crest (vs. marked overlap). We present a molecular-based phylogeny for all available Ptychochromis species, which supports the hypothesis that P. mainty is a distinct taxon. The new species is recovered as the sister taxon to P. grandidieri within a clade comprising species with an eastern-type palatine morphology. We present a geometric morphometric analysis that provides additional evidence to distinguish P. mainty from congeners.

  15. Combating iodine deficiency: lessons from China, Indonesia, and Madagascar.

    PubMed

    Goh, Chor-ching

    2002-09-01

    This study investigated the factors contributing to a successful and sustainable elimination of iodine-deficiency disorders, drawing from salt fortification experiences in China, Indonesia, and Madagascar. Government officials, salt farmers, salt producers, and wholesalers were interviewed to collect data during field visits. Analyses used in the study include simple correlation, and wherever data permit, regression. The study found that measures crucial for combating iodine deficiency include raising public awareness of the disorders, ensuring easy access to iodated salt, promoting compliance in the salt industry, and monitoring and enforcement. Factors that ensure a reliable supply of iodated salt are equally important as those that create the demand for it. Governments must ensure that surveillance and enforcement mechanisms are functioning right from the time that salt iodation is made compulsory. For sustainability during later years, the adequacy of iodine in iodated salt must be monitored, and incentives must be modified as needed to increase compliance rates in the salt industry. Once national coverage of iodated salt reaches over 90%, the government can concentrate on fine-tuning and targeting resources at areas with a low consumption of iodated salt. Elimination of micronutrient deficiencies has a long-term impact on public health; moreover, poorer segments of the population, who are more vulnerable to such deficiencies, have more to gain from fortification programs. Thus, lessons from the successful elimination of iodine-deficiency disorders are valuable for future similar micronutrient activities.

  16. Insatiable demands: Income, energy and environmental policy in Madagascar

    SciTech Connect

    Shaw, C.L.

    1993-01-01

    The island nation of Madagascar is suffering the collision of three distinct trends: economic stagnation, a rapidly expanding population and a severely threatened natural resource base. Demands for growth, new energy reserves and environmental conservation, especially of forest resources, are creating a policy dilemma for both government officials and donors. This study seeks to bring new evidence to bear on this policy dilemma. Primary data on urban household income, family size and consumption of various energy types are used to test two main hypothesis (1) that charcoal, which constitutes the fuel of choice for a vast majority of the sample, is a normal rather than an inferior good, and (2) that demand for wood-fuels constitutes a genuine threat to the viability of the forest resource. The data indicate that income elasticities of demand for charcoal are positive over a broad range of per capita income levels, revealing that charcoal is, indeed a normal good for a large portion of the population represented by the sample. A model of forest degradation is built which establishes a clear link between wood-fuel demand and forest degradation. Together, these findings make clear that under current income patterns, and for the forseeable future, charcoal is a normal good and its consumption by urban residents constitutes a serious threat to the natural forest resource. The study concludes with a policy analysis which identifies existing market failures due to government policies and recommends changes based on tested policy prescriptions in other parts of the developing world.

  17. Atelier paludisme: an international malaria training course held in Madagascar.

    PubMed

    Domarle, Olivier; Randrianarivelojosia, Milijaona; Duchemin, Jean-Bernard; Robert, Vincent; Ariey, Frédéric

    2008-05-09

    The Atelier Paludisme (Malaria Workshop) is an international training course organized by the Institut Pasteur de Madagascar, which has been held annually for the past five years. The course was designed for both young and experienced researchers, as well as for healthcare professionals, mostly from malaria-endemic countries. Its objective is to provide participants with a broad knowledge of all features of malaria, to improve their skills in project management, to break geographical isolation by using the Internet as a source of documentary information. This six-week course makes use of concepts of andragogy and problem-based learning, i.e. a relationship between participants and tutors, which promotes a process of exchange rather than the simple transmission of knowledge, where participants have to search actively for information. This approach to training, combined with the wide background and experience of those involved, creates positive dynamics and enables participants to acquire new skills, develop their critical and analytical abilities. This paper describes the course and the lessons learned from its evaluation.

  18. Atelier paludisme: an international malaria training course held in Madagascar

    PubMed Central

    Domarle, Olivier; Randrianarivelojosia, Milijaona; Duchemin, Jean-Bernard; Robert, Vincent; Ariey, Frédéric

    2008-01-01

    The Atelier Paludisme (Malaria Workshop) is an international training course organized by the Institut Pasteur de Madagascar, which has been held annually for the past five years. The course was designed for both young and experienced researchers, as well as for healthcare professionals, mostly from malaria-endemic countries. Its objective is to provide participants with a broad knowledge of all features of malaria, to improve their skills in project management, to break geographical isolation by using the Internet as a source of documentary information. This six-week course makes use of concepts of andragogy and problem-based learning, i.e. a relationship between participants and tutors, which promotes a process of exchange rather than the simple transmission of knowledge, where participants have to search actively for information. This approach to training, combined with the wide background and experience of those involved, creates positive dynamics and enables participants to acquire new skills, develop their critical and analytical abilities. This paper describes the course and the lessons learned from its evaluation. PMID:18471291

  19. Immunological characteristics of malaria antibodies in two regions of Madagascar.

    PubMed Central

    Deloron, P; Jaureguiberry, G; Gaudebout, C; Le Bras, J; Savel, J; Pocidalo, J J

    1987-01-01

    Antibodies directed against antigens of the asexual blood stages of Plasmodium falciparum were studied in the plasma of 29 individuals infected with P. falciparum and living in two areas of Madagascar. These plasma samples were investigated by four immunological methods: indirect fluorescence, immunoprecipitation of radiolabeled P. falciparum polypeptides, inhibition of the in vitro growth of P. falciparum, and double diffusion in a gelose plate. A multifactorial correspondence analysis of the results obtained for each sample revealed that the nature of several of the antibodies varied according to the age and place of residence of the subjects. In comparison with plasma samples from older individuals, specimens from young children had a higher immunofluorescence titer, immunoprecipitated several additional peptides (90, 110, and 118 kilodaltons), revealed more precipitation lines in the Ouchterlony plate technique, and did not inhibit the in vitro growth of P. falciparum to the same extent. Furthermore, as opposed to plasma samples from individuals living in the high central plateau, plasma samples from individuals living on the east coast of the island inhibited the penetration of erythrocytes by merozoites of one of the two studied P. falciparum strains and preferentially immunoprecipitated low-, rather than high-, molecular-weight peptides. PMID:3108313

  20. Testing the adaptive radiation hypothesis for the lemurs of Madagascar

    PubMed Central

    2017-01-01

    Lemurs, the diverse, endemic primates of Madagascar, are thought to represent a classic example of adaptive radiation. Based on the most complete phylogeny of living and extinct lemurs yet assembled, I tested predictions of adaptive radiation theory by estimating rates of speciation, extinction and adaptive phenotypic evolution. As predicted, lemur speciation rate exceeded that of their sister clade by nearly twofold, indicating the diversification dynamics of lemurs and mainland relatives may have been decoupled. Lemur diversification rates did not decline over time, however, as predicted by adaptive radiation theory. Optimal body masses diverged among dietary and activity pattern niches as lineages diversified into unique multidimensional ecospace. Based on these results, lemurs only partially fulfil the predictions of adaptive radiation theory, with phenotypic evolution corresponding to an ‘early burst’ of adaptive differentiation. The results must be interpreted with caution, however, because over the long evolutionary history of lemurs (approx. 50 million years), the ‘early burst’ signal of adaptive radiation may have been eroded by extinction. PMID:28280597

  1. [Intestinal parasitoses in the Mahajanga region, west coast of Madagascar].

    PubMed

    Buchy, P

    2003-03-01

    A study on human intestinal parasites was carried out from November 1996 until January 1997, in Mahajanga's hospital, on the western coast of Madagascar. We collected the faeces from 401 patients and the sera from 112 of them. Faecal examination using direct examination and MIF method revealed that 67.6% of the stools contained at least one parasite. The frequency of the protozoa was high (47.7%). The prevalence of the nematodosis reached 23.4%. Hymenolepis nana, Taenia saginata or solium and Schistosoma mansoni were less frequent (respectively 2.5%, 0.75% and 3.7%). More than 50% of the sera contained antibodies anti-Ascaris lumbricoides and anti-Strongyloides stercoralis. Serology by IFI using Schistosoma antigen was positive in 15.2% of the cases. The serological and microscopical exams showed that Entamoeba histolytica was present in this region and that amoebiasis should be considered as one of the etiologies of diarrhoea. The study pointed out also the frequency of the transmitted fecal infections. Preventive measures as water distribution, sanitary installations, hygiene education should be implemented.

  2. Age progressive volcanism in the Comores Archipelago and Northern Madagascar

    NASA Astrophysics Data System (ADS)

    Emerick, C. M.

    The Comores islands and Tertiary volcanic province of Northern Madagascar form a sub-linear trend of alkalic shield volvanoes across the northern Mozambique Channel. Potassium-argon dating of shield building lavas confirms an eastward increase in age of volcanism along the chain, consistent with a hotspot origin for the lineament. The rate of migration of the Somali Plate over the mantle source is approximately 45 mm/yr. This new geochronology for the Comores island chain is used to model the absolute motion of the Somali Plate for the last 10 million years. A systematic departure of the Somali Plate absolute motion from the African Plate absolute motion during this period represents a component of relative motion across the East African Rift at the rate of .330 deg/m.y., about an Euler pole located at 63.6 deg. S,2.3. deg. E. The geometry of older portions of the Comores and Reunion trends indicates that there was no significant relative motion between the African and Somali Plates prior to about 10 m.y. ago. Sequential reconstructions from 200-0 m.y. are presented.

  3. [Anopheles funestus and rice agriculture in the Madagascar highlands].

    PubMed

    Marrama, L; Rajaonarivelo, E; Laventure, S; Rabarison, P

    1995-01-01

    An exhaustive study of the potential habitats of Anopheles funestus was led during 1992 in Ankazobe on the Plateau of Madagascar, 95 km northwest of the capital Tananarive. The rice fields provide more than 90% of the positive habitats versus less than 10% for the nonhuman biotopes. Larva are especially abundant on the surfaces of the rice during grain head formation and maturation. The dense vegetation coverage provides them with shade and protection against predators. After harvesting, the follows can be filled with water and wild vegetation, and then also provide an important share of the habitats. The rice fields are omnipresent on the Plateau where they supply the basis of local alimentation. A. funestus then constitutes a serious risk for all of the villages. The role of the rice fields as habitats for A. funestus has already been noted in Kenya but in West Africa the rice fields do not host this species, even if this species is very abundant in the other types of habitats.

  4. Drivers of Rift Valley fever epidemics in Madagascar.

    PubMed

    Lancelot, Renaud; Béral, Marina; Rakotoharinome, Vincent Michel; Andriamandimby, Soa-Fy; Héraud, Jean-Michel; Coste, Caroline; Apolloni, Andrea; Squarzoni-Diaw, Cécile; de La Rocque, Stéphane; Formenty, Pierre B H; Bouyer, Jérémy; Wint, G R William; Cardinale, Eric

    2017-01-31

    Rift Valley fever (RVF) is a vector-borne viral disease widespread in Africa. The primary cycle involves mosquitoes and wild and domestic ruminant hosts. Humans are usually contaminated after contact with infected ruminants. As many environmental, agricultural, epidemiological, and anthropogenic factors are implicated in RVF spread, the multidisciplinary One Health approach was needed to identify the drivers of RVF epidemics in Madagascar. We examined the environmental patterns associated with these epidemics, comparing human and ruminant serological data with environmental and cattle-trade data. In contrast to East Africa, environmental drivers did not trigger the epidemics: They only modulated local Rift Valley fever virus (RVFV) transmission in ruminants. Instead, RVFV was introduced through ruminant trade and subsequent movement of cattle between trade hubs caused its long-distance spread within the country. Contact with cattle brought in from infected districts was associated with higher infection risk in slaughterhouse workers. The finding that anthropogenic rather than environmental factors are the main drivers of RVF infection in humans can be used to design better prevention and early detection in the case of RVF resurgence in the region.

  5. Testing the adaptive radiation hypothesis for the lemurs of Madagascar.

    PubMed

    Herrera, James P

    2017-01-01

    Lemurs, the diverse, endemic primates of Madagascar, are thought to represent a classic example of adaptive radiation. Based on the most complete phylogeny of living and extinct lemurs yet assembled, I tested predictions of adaptive radiation theory by estimating rates of speciation, extinction and adaptive phenotypic evolution. As predicted, lemur speciation rate exceeded that of their sister clade by nearly twofold, indicating the diversification dynamics of lemurs and mainland relatives may have been decoupled. Lemur diversification rates did not decline over time, however, as predicted by adaptive radiation theory. Optimal body masses diverged among dietary and activity pattern niches as lineages diversified into unique multidimensional ecospace. Based on these results, lemurs only partially fulfil the predictions of adaptive radiation theory, with phenotypic evolution corresponding to an 'early burst' of adaptive differentiation. The results must be interpreted with caution, however, because over the long evolutionary history of lemurs (approx. 50 million years), the 'early burst' signal of adaptive radiation may have been eroded by extinction.

  6. Maternal health practices, beliefs and traditions in southeast Madagascar.

    PubMed

    Morris, Jessica L; Short, Samm; Robson, Laura; Andriatsihosena, Mamy Soafaly

    2014-09-01

    Contextualising maternal health in countries with high maternal mortality is vital for designing and implementing effective health interventions. A research project was therefore conducted to explore practices, beliefs and traditions around pregnancy, delivery and postpartum in southeast Madagascar. Interviews and focus groups were conducted with 256 pregnant women, mothers of young children, community members and stakeholders; transcripts were analysed to identify and explore predetermined and emerging themes. A questionnaire was also conducted with 373 women of reproductive age from randomly selected households. Data was analysed using STATA. Results confirmed high local rates of maternal mortality and morbidity and revealed a range of traditional health care practices and beliefs impacting on women's health seeking behaviours. The following socio-cultural barriers to health were identified: 1) lack of knowledge, 2) risky practices, 3) delays seeking biomedical care, and 4) family and community expectations. Recommendations include educational outreach and behaviour change communications targeted for women, their partners and family, increased engagement with traditional midwives and healers, and capacity building of formal health service providers.

  7. Timing of hot spot--related volcanism and the breakup of madagascar and India.

    PubMed

    Storey, M; Mahoney, J J; Saunders, A D; Duncan, R A; Kelley, S P; Coffin, M F

    1995-02-10

    Widespread basalts and rhyolites were erupted in Madagascar during the Late Cretaceous. These are considered to be related to the Marion hot spot and the breakup of Madagascar and Greater India. Seventeen argon-40/argon-39 age determinations reveal that volcanic rocks and dikes from the 1500-kilometer-long rifted eastern margin of Madagascar were emplaced rapidly (mean age = 87.6 +/- 0.6 million years ago) and that the entire duration of Cretaceous volcanism on the island was no more than 6 million years. The evidence suggests that the thick lava pile at Volcan de l'Androy in the south of the island marks the focal point of the Marion hot spot at approximately 88 million years ago and that this mantle plume was instrumental in causing continental breakup.

  8. Miocene Shark and Batoid Fauna from Nosy Makamby (Mahajanga Basin, Northwestern Madagascar)

    PubMed Central

    Andrianavalona, Tsiory H.; Ramihangihajason, Tolotra N.; Rasoamiaramanana, Armand; Ward, David J.; Ali, Jason R.; Samonds, Karen E.

    2015-01-01

    Madagascar is well known for producing exceptional fossils. However, the record for selachians remains relatively poorly known. Paleontological reconnaissance on the island of Nosy Makamby, off northwest Madagascar, has produced a previously undescribed assemblage of Miocene fossils. Based on isolated teeth, ten taxonomic groups are identified: Otodus, Carcharhinus, Galeocerdo, Rhizoprionodon, Sphyrna, Hemipristis, Squatina, Rostroraja, Himantura and Myliobatidae. Six are newly described from Madagascar for the Cenozoic (Galeocerdo, Rhizoprionodon, Sphyrna, Squatina, Rostroraja and Himantura). In association with these specimens, remains of both invertebrates (e.g., corals, gastropods, bivalves) and vertebrates (e.g., bony fish, turtles, crocodylians, and sirenian mammals) were also recovered. The sedimentary facies are highly suggestive of a near-shore/coastal plain depositional environment. This faunal association shares similarities to contemporaneous sites reported from North America and Europe and gives a glimpse into the paleoenvironment of Madagascar’s Miocene, suggesting that this region was warm, tropical shallow-water marine. PMID:26075723

  9. Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle

    USGS Publications Warehouse

    Johnson, J.A.; Tingay, R.E.; Culver, M.; Hailer, F.; Clarke, M.L.; Mindell, D.P.

    2009-01-01

    The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape. ?? 2008 The Authors.

  10. Speleothem isotopic evidence for rapid human-induced expansion of grasslands in Madagascar at 890 CE

    NASA Astrophysics Data System (ADS)

    Burns, S. J.; Godfrey, L.; Faina, P.; McGee, D.; Hardt, B. F.; Ranivoharimanana, L.; Randrianasy, J.

    2015-12-01

    The degree to which human activity impacted the landscape, vegetation and fauna of Madagascar remains under debate. Since the early 1920's, the prevailing hypothesis has been that the savannah grasslands that now cover 70% of Madagascar were the result of deforestation, which has also been tied to the disappearance of much of the island's endemic megafauna. Other studies suggest that Madagascar's grasslands are largely natural and that megafaunal extinctions may be climatically induced, leading some authors to question the entire narrative of extensive alteration of the landscape by early human activity. We collected two stalagmites, M14-AB2 and M14-AB3, from Anjohibe Cave in northwestern Madagascar (15.55°S, 46.89°E, 100 masl). Age models were constructed using 8 U/Th age determinations from AB2 and 10 from AB3. The samples began to grow at ~500 CE and were active at the time of collection. Carbon and oxygen stable isotope ratios were measured on 266 samples from AB2 and 173 samples from AB3, yielding sub-decadal temporal resolution. A rapid, more than 10 per mil increase in stalagmite carbon stable isotope ratios documents an almost complete transformation of the landscape from one with a flora dominated by C3 plants to a C4 grassland system. This transformation, well replicated in both stalagmites, occurred at approximately 890 +/- 20 CE and was complete in 100 years. Further, relatively constant oxygen isotope ratios across the carbon isotope transition demonstrate that landscape alteration was not related to changes in climate. We hypothesize that the transformation was caused primarily by expansion of the use of fire by early inhabitants of Madagascar to promote agriculture and the growth of grass as fodder for cattle. The resulting loss of forest habitat very likely increased environmental pressures on Madagascar's megafauna and accelerated their disappearance.

  11. Receiver function analysis and preliminary body wave tomography of the MACOMO network in Madagascar

    NASA Astrophysics Data System (ADS)

    Pratt, M. J.; Wysession, M. E.; Wiens, D. A.; Nyblade, A.; Aleqabi, G. I.; Shore, P.; Rambolamana, G.; Sy Tanjona Andriampenomanana ny Ony, F.; Rakotondraibe, T.

    2013-12-01

    We present results from a set of seismological studies of the continental island of Madagascar using new seismic data from the NSF-funded MACOMO (MAdagascar, COmores, and MOzambique) IRIS PASSCAL broadband seismometer array. MACOMO involved the deployment during 2011-2013 of 26 broadband seismometers in Madagascar and 6 seismometers in Mozambique, providing the first seismic imaging across the world's 4th-largest island. We present preliminary crustal structure variations from receiver function analyses and body wave tomography results. We calculate radial receiver functions for all Madagascar stations and use the weighted linear regression methodology of Herrmann and Ammon [2002] to invert for shear velocity. Upper mantle and crustal structures from the receiver function analyses are used to help determine starting models for the teleseismic travel-time tomography. The tectonic structure of Madagascar is generally divided into four crustal blocks. Initial seismic imaging shows that the Archean Antongil block that runs along the east of the island has the thickest crust (>40 km) and three Proterozoic terranes that make up the central highlands and are bounded by fault and shear zones are closer to the average crustal thickness (35 km). There has been late Cenozoic intraplate volcanism in northern and central Madagascar (as recently as 1 million years ago), and different hypotheses for its origin will be evaluated by the preliminary results from the three different seismic studies. Complete analyses will be done incorporating seismic data from simultaneous and complementary array of both land- and ocean-based seismometers from French and German deployments.

  12. Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle.

    PubMed

    Johnson, Jeff A; Tingay, Ruth E; Culver, Melanie; Hailer, Frank; Clarke, Michèle L; Mindell, David P

    2009-01-01

    The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape.

  13. A Cenozoic Record of Uplift, Erosion and Dynamic Support: Examples from Madagascar

    NASA Astrophysics Data System (ADS)

    Stephenson, S.; White, N.

    2015-12-01

    The physiography of Madagascar is characterised by high-elevation and low relief topography. Cretaceous limestones at elevations of ~300 m above sea level and newly dated emergent ~125 ka coral reefs suggest that Madagascar and its margins have been uplifted during Cenozoic times. Rivers in Madagascar are often deeply incised and contain steepened reaches, which implies that they are responding to changes in uplift rate. However, apatite fission track and (U-Th)/He thermochronology, and 10Be derived erosion rates suggest that both Cenozoic and recent denudation rates have been low. Extensive laterite-capped flat surfaces also suggest there were long periods of tectonic quiescence during the Cenozoic. To bridge the gap between evidence for uplift and quiescence, we inverted 2566 longitudinal river profiles using a damped non-negative, least-squares inversion scheme for histories of uplift rate. We used a simplified version of the stream power erosional model (∂z/∂t = -KAmSn + U, where n = 1). Longitudinal profiles were extracted from the 90 m resolution Shuttle Radar Topography Mission (SRTM) digital elevation model. Calibration of the stream power erosional model is based on new radiometric dating of marine terraces and incised lateritic peneplains. Fits to observed river profiles are excellent. Results indicate that Madagascar's topography grew by 1 - 2 km during the last 15-20 Ma. Calculated uplift and denudation is consistent with independent observations. Our results suggest that drainage networks in Madagascar contain coherent signals that record regional uplift. Admittance calculations and nearby oceanic residual age-depth measurements from the passive margins suggest that as much as 0.8 - 1.1 km of Cenozoic uplift in Madagascar was supported by the mantle.

  14. Comprehensive Red List assessment reveals exceptionally high extinction risk to Madagascar palms.

    PubMed

    Rakotoarinivo, Mijoro; Dransfield, John; Bachman, Steven P; Moat, Justin; Baker, William J

    2014-01-01

    The establishment of baseline IUCN Red List assessments for plants is a crucial step in conservation planning. Nowhere is this more important than in biodiversity hotspots that are subject to significant anthropogenic pressures, such as Madagascar. Here, all Madagascar palm species are assessed using the IUCN Red List categories and criteria, version 3.1. Our results indicate that 83% of the 192 endemic species are threatened, nearly four times the proportion estimated for plants globally and exceeding estimates for all other comprehensively evaluated plant groups in Madagascar. Compared with a previous assessment in 1995, the number of Endangered and Critically Endangered species has substantially increased, due to the discovery of 28 new species since 1995, most of which are highly threatened. The conservation status of most species included in both the 1995 and the current assessments has not changed. Where change occurred, more species have moved to lower threat categories than to higher categories, because of improved knowledge of species and their distributions, rather than a decrease in extinction risk. However, some cases of genuine deterioration in conservation status were also identified. Palms in Madagascar are primarily threatened by habitat loss due to agriculture and biological resource use through direct exploitation or collateral damage. The recent extension of Madagascar's protected area network is highly beneficial for palms, substantially increasing the number of threatened species populations included within reserves. Notably, three of the eight most important protected areas for palms are newly designated. However, 28 threatened and data deficient species are not protected by the expanded network, including some Critically Endangered species. Moreover, many species occurring in protected areas are still threatened, indicating that threatening processes persist even in reserves. Definitive implementation of the new protected areas combined with

  15. The Toarcian Bathonian succession of the Antsiranana Basin (NW Madagascar): Facies analysis and tectono-sedimentary history in the development of the East Africa-Madagascar conjugate margins

    NASA Astrophysics Data System (ADS)

    Papini, Mauro; Benvenuti, Marco

    2008-04-01

    The latest Early to Middle Jurassic succession of the Antsiranana Basin (NW Madagascar) records the complex transition from the continental rifting of Gondwana to the drifting of Madagascar-India from East Africa. The Madagascan Late Paleozoic-Mesozoic successions have been included in several paleogeographic and geodynamic models explaining the evolution of the Gondwana margins. Nevertheless, in some cases, as for the Toarcian-Bathonian deposits of the Antsiranana Basin, no significant stratigraphic revision has been carried out since the early 1970s. New field surveys allow reconsidering the stratigraphic and structural context and the palaeoenvironmental meaning of Toarcian-Bathonian successions occurring in different parts of the basin. These successions rest on the Triassic-Early Jurassic Isalo Sandstone which records pre-breakup rift events with a dominantly fluvial deposition. This situation is similar to other continental rift basins of Gondwana. After a regional Toarcian transgression the different portions of the Antsiranana Basin were characterized by significantly diversified and coeval depositional environments. The basin can be subdivided in a SW and NE part separated by a NW-SE trending structural high. In the SW part of the basin (Ampasindava sub-basin) the so-called "Jurassique paralique" [Rerat, J.C., 1964. Note sur les variations de faciès des sèries jurassiques du nord de Madagascar. Comptes Rendus Semaine gèologique, Tananarive, pp. 15-22] or " Facies Mixtes de la Presqu'ile de Ampasindava" [Besairie, H., Collignon, M., 1972. Géologie de Madagascar; I. Les terrains sédimentaires. Annales Géologiques de Madagascar, 35, 1-463], a 1500 m thick prevalently terrigenous deposit, has been subdivided into four units. They document the long-lasting development of coastal-deltaic systems in a highly subsiding area. In the NE portion of the basin (Ankarana-Analamera sub-basin), a coeval mixed carbonate-terrigenous succession subdivided in five units

  16. [HIV infection in tuberculosis patients in Madagascar. Situation in 1-93].

    PubMed

    Morvan, J M; Auregan, G; Rasamindrakotroka, A J; de Ravel, T; Roux, J F

    1994-01-01

    In Madagascar, the estimated incidence of tuberculosis is high (320 per 100,000) when human immunodeficiency virus (VIH) infection progress slowly. The authors have studied HIV seroprevalence in a group of tubercular patients and in two reference groups (general population and outpatients of the Clinical Biology Centre of Institut Pasteur). Circulation of HIV1 virus was observed with a low prevalence rate in all the 3 groups. There was no significant difference between tubercular patients and healthy population. Tubercular people ought to be a watch group for the epidemiological surveillance of HIV infection evolution in Madagascar.

  17. Surveillance and control of rabies in La Reunion, Mayotte, and Madagascar

    PubMed Central

    2013-01-01

    Mayotte and La Reunion islands are currently free of animal rabies and surveillance is performed by the French Human and Veterinary Public Health Services. However, dog rabies is still enzootic in Madagascar with 4 to 10 confirmed human cases each year. The number of antirabies medical centres in Madagascar is still scarce to provide easy access to the local population for post-exposure rabies prophylaxis. Furthermore, stray dog populations are considerable and attempts to control rabies by mass campaigns of dog vaccination have not received sufficient attention from the national health authorities. To address these challenges, an expanded program to control rabies needs to be initiated by the Malagasy authorities. PMID:24016204

  18. Genetic diversity and population structure of Plasmodium vivax isolates from Sudan, Madagascar, French Guiana and Armenia.

    PubMed

    Menegon, Michela; Durand, Patrick; Menard, Didier; Legrand, Eric; Picot, Stéphane; Nour, Bakri; Davidyants, Vladimir; Santi, Flavia; Severini, Carlo

    2014-10-01

    Polymorphic genetic markers and especially microsatellite analysis can be used to investigate multiple aspects of the biology of Plasmodium species. In the current study, we characterized 7 polymorphic microsatellites in a total of 281 Plasmodium vivax isolates to determine the genetic diversity and population structure of P. vivax populations from Sudan, Madagascar, French Guiana, and Armenia. All four parasite populations were highly polymorphic with 3-32 alleles per locus. Mean genetic diversity values was 0.83, 0.79, 0.78 and 0.67 for Madagascar, French Guiana, Sudan, and Armenia, respectively. Significant genetic differentiation between all four populations was observed.

  19. Low-temperature evolution of the Morondava rift shoulder in western Madagascar

    NASA Astrophysics Data System (ADS)

    Giese, Jörg; Seward, Diane; Schreurs, Guido

    2010-05-01

    Separation of Madagascar from eastern Africa resulted in the development of sedimentary basins covering the west coast of Madagascar. The largest and oldest of these basins, the Morondava basin, is bound to the east by crystalline basement of Precambrian age and stretches into the Mozambique Channel to the west. The evolution of the sedimentary sequence is mainly influenced by (I) a Permo-Triassic continental failed rift (e.g. Clark, 1998), also referred to as the Karroo rift (e.g., Montenat et al., 1996) and (II) the early Jurassic separation of Madagascar from eastern Africa (Geiger et al., 2004). Deposits related to the Karroo rift are restricted to a narrow corridor along the basement-basin contact. The rift locus shifted to the west before final separation and relative southward displacement of Madagascar commenced in early Jurassic times (Geiger et al., 2004). In the central part of the basin, the basement-basin contact features a steep escarpment with an altitude difference of greater than 1000 m from the sedimentary plains to the crystalline basement. Here, apatite fission-track analysis of a series of both basement and sediment samples across the escarpment provides the possibility to study the low temperature evolution of the exhuming Precambrian basement in the rift basin shoulder and the associated thermal evolution of the sedimentary succession. The timing of basement surface exposure is constrained by the stratigraphic ages of the overlying sediments and modelling of the thermal evolution indicates post-depositional thermal overprinting of basement and Karroo age sediments with partial annealing of fission tracks related to burial by Mesozoic sediments. The temperatures of this heating / reheating of the basin shoulder increase towards the west in the presently exposed sequences. The westernmost sample experienced almost complete resetting of the detrital apatite grains. The general younging of the apparent apatite fission-track ages towards the west

  20. Overview of accessibility and quality of antiepileptic drugs in Madagascar.

    PubMed

    Nizard, Mandy; Jost, Jérémy; Tanamasoandro, Rakotovao; Andriambololona, Rindra; Megherbi, Mehdi; Solofomalala, Gaetan Duval; Marquet, Pierre; Preux, Pierre-Marie; Ratsimbazafy, Voa

    2016-10-01

    To determine the accessibility of treatment and the quality of antiepileptic drugs (AEDs) in the Haute Matsiatra district of Madagascar. Cross-sectional descriptive study and interviews. Samples of 10 units of each available AED were collected, and the active ingredient was quantified by reversed-phase high-performance liquid chromatography (RP-HPLC) with photodiode-array UV detection. The quality of an AED was considered satisfactory if the quantity of active ingredient in each tablet was in the range ±15% of the average value according to the European Pharmacopeia (6th edition, 2008). The area was well served with health infrastructure but rescue facilities were poorly distributed. Available AEDs were all first-generation, and 73% were generic formulations. People with epilepsy (PWE) surveyed consulted traditional healers and most were treated with plants. PWE did not consider themselves sick but believed they were "possessed"; they consulted a doctor only immediately after a seizure, following the advice of traditional healers. The most prescribed AED was phenobarbital, costing between 0.03 and 0.12 US Dollar (US$) per 100mg. The purchase of full treatment was difficult for 77% of PWE and as a result, 39% took nothing. The quality of AEDs were considered unsatisfactory in 2.8% of cases. The AEDs collected in Haute Matsiatra were globally of good quality. The main limiting elements were a lack of knowledge among PWE that epilepsy is a disease, and the cost of traditional treatments. Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  1. Blindness and cataract surgical services in Atsinanana region, Madagascar.

    PubMed

    Randrianaivo, Jean-Baptiste; Anholt, R Michele; Tendrisoa, Diarimirindra Lazaharivony; Margiano, Nestor Jean; Courtright, Paul; Lewallen, Susan

    2014-01-01

    To assess the prevalence and causes of avoidable blindness in Atsinanana Region, Madagascar, with the Rapid Assessment of Avoidable Blindness (RAAB) survey. We analyzed the hospital records to supplement the findings for public health care planning. Only villages within a two-hour walk from a road, about half of the population of Atsinanana was included. Seventy-two villages were selected by population-proportional-to-size sampling. In each village, compact segment sampling was used to select 50 people over age 50 for eye examination using standard RAAB methods. Records at the two hospitals providing cataract surgery in the region were analyzed for information on patients who underwent cataract surgery in 2010. Cataract incidence rate and target cataract surgery rate (CSR) was modeled from age-specific prevalence of cataract. The participation rate was 87% and the sample prevalence of blindness was 1.96%. Cataract was responsible for 64% and 85.7% of blindness and severe visual impairment, respectively. Visual impairment was due to cataract (69.4%) and refractive error (14.1%). There was a strong positive correlation between cataract surgical rate by district and the proportion of people living within 2 hours of a road. There were marked differences in the profiles of the cataract patients at the two facilities. The estimated incidence of cataract at the 6/18 level was 2.4 eyes per 100 people over age 50 per year. Although the survey included only people with reasonable access, the main cause of visual impairment was still cataract. The incidence of cataract is such that it ought to be possible to eliminate it as a cause of visual impairment, but changes in service delivery at hospitals and strategies to improve access will be necessary for this change.

  2. Delimiting Species without Nuclear Monophyly in Madagascar's Mouse Lemurs

    PubMed Central

    Weisrock, David W.; Rasoloarison, Rodin M.; Fiorentino, Isabella; Ralison, José M.; Goodman, Steven M.; Kappeler, Peter M.; Yoder, Anne D.

    2010-01-01

    Background Speciation begins when populations become genetically separated through a substantial reduction in gene flow, and it is at this point that a genetically cohesive set of populations attain the sole property of species: the independent evolution of a population-level lineage. The comprehensive delimitation of species within biodiversity hotspots, regardless of their level of divergence, is important for understanding the factors that drive the diversification of biota and for identifying them as targets for conservation. However, delimiting recently diverged species is challenging due to insufficient time for the differential evolution of characters—including morphological differences, reproductive isolation, and gene tree monophyly—that are typically used as evidence for separately evolving lineages. Methodology In this study, we assembled multiple lines of evidence from the analysis of mtDNA and nDNA sequence data for the delimitation of a high diversity of cryptically diverged population-level mouse lemur lineages across the island of Madagascar. Our study uses a multi-faceted approach that applies phylogenetic, population genetic, and genealogical analysis for recognizing lineage diversity and presents the most thoroughly sampled species delimitation of mouse lemur ever performed. Conclusions The resolution of a large number of geographically defined clades in the mtDNA gene tree provides strong initial evidence for recognizing a high diversity of population-level lineages in mouse lemurs. We find additional support for lineage recognition in the striking concordance between mtDNA clades and patterns of nuclear population structure. Lineages identified using these two sources of evidence also exhibit patterns of population divergence according to genealogical exclusivity estimates. Mouse lemur lineage diversity is reflected in both a geographically fine-scaled pattern of population divergence within established and geographically widespread taxa

  3. Economic Valuation of Subsistence Harvest of Wildlife in Madagascar

    PubMed Central

    Golden, Christopher D.; Bonds, Matthew H.; Brashares, Justin S.; Rasolofoniaina, B. J. Rodolph; Kremen, Claire

    2014-01-01

    Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlife’s ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha−1 · year−1. Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local people’s food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife. PMID:24405165

  4. [International clinical practice guidelines and management of rheumatology in Madagascar].

    PubMed

    Ralandison, S; Rafalimanana, E; Rakotonirainy, H; Rabenja, R

    2012-02-01

    Developed countries issue recommendations regarding healthcare that aren't constantly appropriate for emergent countries. We suggest some remarks concerning rheumatology in Madagascar, taking account of scientific data, medical ethics, equality and equity. We have studied the minimal cost of care of medical conditions found in our hospital department if we were to follow international recommendations for their management. Then, we have estimated treatment expenses as a percentage of the SMIC (Malagasy minimum monthly salary). Out of 517 patients examined yearly, we have found 62.8% osteoarthritis cases, 6.3% rheumatoid arthritis (RA), and 4,2% septic arthritis. Therefore, the first month of treatment for an arthritis of the knee would absorb 147.3% of the SMIC; diagnosis and treatment of a case of septic arthritis would take up 1762.8% of the minimum wage, and a case of RA without biotherapy would require 175%. According to the American College of Rheumatology criteria which are used as a reference, the treatment of an arthritis of the knee would take only 23% of the SMIC. Caring for septic arthritis would demand 57.5% of the SMIC and while it would yield more arguments for diagnosis such as clinical examination, CRP, and Gram coloration on joint liquid aspiration. We can proceed to RA diagnosis with an acceptable security through precise clinical examination, blood cell count, ESR, CRP, rheumatoid factor and radiography. This means 56% of the SMIC. From this 517 patients, our suggestions would reduce the expense by 35,850% of the SMIC per year. The allocation of such funds onto the treatment of complicated forms of rheumatism would be fair. By refining and evaluating these suggestions, we would come up with appropriate recommendations for emergent countries.

  5. Blindness and Cataract Surgical Services in Atsinanana Region, Madagascar

    PubMed Central

    Randrianaivo, Jean-Baptiste; Anholt, R. Michele; Tendrisoa, Diarimirindra Lazaharivony; Margiano, Nestor Jean; Courtright, Paul; Lewallen, Susan

    2014-01-01

    Purpose: To assess the prevalence and causes of avoidable blindness in Atsinanana Region, Madagascar, with the Rapid Assessment of Avoidable Blindness (RAAB) survey. We analyzed the hospital records to supplement the findings for public health care planning. Materials and Methods: Only villages within a two-hour walk from a road, about half of the population of Atsinanana was included. Seventy-two villages were selected by population-proportional-to-size sampling. In each village, compact segment sampling was used to select 50 people over age 50 for eye examination using standard RAAB methods. Records at the two hospitals providing cataract surgery in the region were analyzed for information on patients who underwent cataract surgery in 2010. Cataract incidence rate and target cataract surgery rate (CSR) was modeled from age-specific prevalence of cataract. Results: The participation rate was 87% and the sample prevalence of blindness was 1.96%. Cataract was responsible for 64% and 85.7% of blindness and severe visual impairment, respectively. Visual impairment was due to cataract (69.4%) and refractive error (14.1%). There was a strong positive correlation between cataract surgical rate by district and the proportion of people living within 2 hours of a road. There were marked differences in the profiles of the cataract patients at the two facilities. The estimated incidence of cataract at the 6/18 level was 2.4 eyes per 100 people over age 50 per year. Conclusions: Although the survey included only people with reasonable access, the main cause of visual impairment was still cataract. The incidence of cataract is such that it ought to be possible to eliminate it as a cause of visual impairment, but changes in service delivery at hospitals and strategies to improve access will be necessary for this change. PMID:24791107

  6. Economic valuation of subsistence harvest of wildlife in Madagascar.

    PubMed

    Golden, Christopher D; Bonds, Matthew H; Brashares, Justin S; Rasolofoniaina, B J Rodolph; Kremen, Claire

    2014-02-01

    Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlife's ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha(-1) · year(-1). Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local people's food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife.

  7. [Virus Manombo (Mg Ar 966), a provisionally new arbovirus isolated from Culicidae in Madagascar].

    PubMed

    Morvan, J; Fontenille, D; Digoutte, J P; Rakotoarivony, I; Coulanges, P

    1991-01-01

    In April 1987, a virus strain was isolated from a pool of Mansonia uniformis caught on human bait, in a tropical primary rain forest area of the South-East coast of Madagascar. Antigenically, this virus may not be related to other known viruses, and constitutes a provisionally new Arbovirus called virus Manombo.

  8. In vitro response of Plasmodium falciparum to chloroquine and mefloquine in southeast Madagascar.

    PubMed

    Kightlinger, M B; Kightlinger, L K

    1988-01-01

    46 isolates of Plasmodium falciparum collected in the Tolagnaro (Fort Dauphin) area of Southeast Madagascar were assessed with WHO in vitro micro-technique test kits to determine their susceptibility to chloroquine and mefloquine. The results of the tests indicated low grade resistance to chloroquine and satisfactory response to mefloquine.

  9. Home Sweet Home: How to Build a Madagascar Hissing Cockroach Habitat out of Recycled Materials

    ERIC Educational Resources Information Center

    Wagler, Ron

    2010-01-01

    Madagascar hissing cockroaches (MHC) are amazing insects that can be an integral part of an effective science learning and teaching environment. MHCs have a fascinating social structure. They make excellent pets, teach students how to properly care for animals, and their large size adds to their "wow" factor. These characteristics make them unique…

  10. Genetics of the Pig Tapeworm in Madagascar Reveal a History of Human Dispersal and Colonization

    PubMed Central

    Yanagida, Tetsuya; Carod, Jean-François; Sako, Yasuhito; Nakao, Minoru; Hoberg, Eric P.; Ito, Akira

    2014-01-01

    An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation. PMID:25329310

  11. Hybridization between mouse lemurs in an ecological transition zone in southern Madagascar.

    PubMed

    Gligor, M; Ganzhorn, J U; Rakotondravony, D; Ramilijaona, O R; Razafimahatratra, E; Zischler, H; Hapke, A

    2009-02-01

    Hybrid zones in ecotones can be useful model systems for the study of evolutionary processes that shape the distribution and discreteness of species. Such studies could be important for an improved understanding of the complex biogeography of Madagascar, which is renowned for its outstanding degree of small-scale endemism. Certain forest remnants in central Madagascar indicate that transitional corridors across the island could have connected microendemics in different forest types in the past. Evolutionary processes in such corridors are difficult to study because most of these corridors have disappeared due to deforestation in central Madagascar. We studied a hybrid zone in one of the few remaining ecotonal corridors between dry and humid forests in Madagascar, which connects two species of mouse lemurs, Microcebus griseorufus in dry spiny forest and Microcebus murinus in humid littoral forest. We sampled 162 mouse lemurs at nine sites across this boundary. Morphometric analyses revealed intermediate morphotypes of many individuals in transitional habitat. Bayesian clustering of microsatellite genotypes and assignment tests yielded evidence for a mixed ancestry of mouse lemurs in the ecotone, where we also observed significant linkage disequilibria and heterozygote deficiency. In contrast to these observations, mitochondrial haplotypes displayed a sharply delimited boundary at the eastern edge of spiny forest, which was noncoincident with the signals from microsatellite data. Among several alternative scenarios, we propose asymmetric nuclear introgression due to male-biased dispersal, divergent environmental selection, and an expansion of dry spiny forest in the course of aridification as a probable explanation of our observations.

  12. Aye-aye population genomic analyses highlight an important center of endemism in northern Madagascar.

    PubMed

    Perry, George H; Louis, Edward E; Ratan, Aakrosh; Bedoya-Reina, Oscar C; Burhans, Richard C; Lei, Runhua; Johnson, Steig E; Schuster, Stephan C; Miller, Webb

    2013-04-09

    We performed a population genomics study of the aye-aye, a highly specialized nocturnal lemur from Madagascar. Aye-ayes have low population densities and extensive range requirements that could make this flagship species particularly susceptible to extinction. Therefore, knowledge of genetic diversity and differentiation among aye-aye populations is critical for conservation planning. Such information may also advance our general understanding of Malagasy biogeography, as aye-ayes have the largest species distribution of any lemur. We generated and analyzed whole-genome sequence data for 12 aye-ayes from three regions of Madagascar (North, West, and East). We found that the North population is genetically distinct, with strong differentiation from other aye-ayes over relatively short geographic distances. For comparison, the average FST value between the North and East aye-aye populations--separated by only 248 km--is over 2.1-times greater than that observed between human Africans and Europeans. This finding is consistent with prior watershed- and climate-based hypotheses of a center of endemism in northern Madagascar. Taken together, these results suggest a strong and long-term biogeographical barrier to gene flow. Thus, the specific attention that should be directed toward preserving large, contiguous aye-aye habitats in northern Madagascar may also benefit the conservation of other distinct taxonomic units. To help facilitate future ecological- and conservation-motivated population genomic analyses by noncomputational biologists, the analytical toolkit used in this study is available on the Galaxy Web site.

  13. Surface Response to Regional Uplift of Madagascar Reveals Short Wavelength Dynamic Topography

    NASA Astrophysics Data System (ADS)

    Stephenson, S.; White, N.

    2016-12-01

    The physiography of Madagascar is characterized by high elevation but low relief topography with 42% of the landscape at an elevation grgeater than 500 m. Eocene marine limestones crop out at an elevation of 400 m, extensive low relief erosion surfaces capped by laterites occur at elevations of up to 2 km, and longitudinal river profiles are disequilibrated. Together, these observations suggest that Madagascar underwent regional uplift in Neogene times. Inverse modeling of drainage networks suggests that regional uplift is diachronous and has occurred on wavelengths of 1000 km. The existence of deeply incised river channels together with low-temperature thermochronologic measurements (i.e. AFT, AHe) implies that erosion occurred in response to regional Neogene uplift. Admittance analysis of long wavelength free-air gravity and topography shows that admittance, Z = 45 ± 5 mGal/km. The history of Neogene volcanism and a lack of significant tectonic shortening both suggest that uplift is dynamically supported. Here we present a suite of U-Th dates of emergent coral reef deposits from northern Madagascar, whose margins are sometimes considered `stable'. Elevation of these coeval coral reefs decreases from 7.2 m at the northern tip of Madagascar to sea level 100 km to the south. The existence of a spatial gradient suggests that differential vertical motions occurred during Late Quaternary times. These results raise significant questions about the reliability both of emergent coral reefs as global sea-level markers and the length-scale of variations in dynamic topography.

  14. Examining the Environmental Awareness of Children and Adolescents in the Ranomafana Region, Madagascar

    ERIC Educational Resources Information Center

    Korhonen, Kaisa; Lappalainen, Anu

    2004-01-01

    This paper examines children's and adolescents' environmental awareness in rural Madagascar. Two types of school survey among 8- to 21-year-old students and pupils in 18 schools were used for data collection. The objective of this comparative study was to examine the environmental awareness and knowledge of children and adolescents living under…

  15. Diverse Genotypes of Yersinia pestis Caused Plague in Madagascar in 2007.

    PubMed

    Riehm, Julia M; Projahn, Michaela; Vogler, Amy J; Rajerison, Minoaerisoa; Andersen, Genevieve; Hall, Carina M; Zimmermann, Thomas; Soanandrasana, Rahelinirina; Andrianaivoarimanana, Voahangy; Straubinger, Reinhard K; Nottingham, Roxanne; Keim, Paul; Wagner, David M; Scholz, Holger C

    2015-06-01

    Yersinia pestis is the causative agent of human plague and is endemic in various African, Asian and American countries. In Madagascar, the disease represents a significant public health problem with hundreds of human cases a year. Unfortunately, poor infrastructure makes outbreak investigations challenging. DNA was extracted directly from 93 clinical samples from patients with a clinical diagnosis of plague in Madagascar in 2007. The extracted DNAs were then genotyped using three molecular genotyping methods, including, single nucleotide polymorphism (SNP) typing, multi-locus variable-number tandem repeat analysis (MLVA), and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) analysis. These methods provided increasing resolution, respectively. The results of these analyses revealed that, in 2007, ten molecular groups, two newly described here and eight previously identified, were responsible for causing human plague in geographically distinct areas of Madagascar. Plague in Madagascar is caused by numerous distinct types of Y. pestis. Genotyping method choice should be based upon the discriminatory power needed, expense, and available data for any desired comparisons. We conclude that genotyping should be a standard tool used in epidemiological investigations of plague outbreaks.

  16. Home Sweet Home: How to Build a Madagascar Hissing Cockroach Habitat out of Recycled Materials

    ERIC Educational Resources Information Center

    Wagler, Ron

    2010-01-01

    Madagascar hissing cockroaches (MHC) are amazing insects that can be an integral part of an effective science learning and teaching environment. MHCs have a fascinating social structure. They make excellent pets, teach students how to properly care for animals, and their large size adds to their "wow" factor. These characteristics make them unique…

  17. THE subfossil occurrence and paleoecological significance of small mammals at ankilitelo cave, southwestern Madagascar

    USGS Publications Warehouse

    Muldoon, K.M.; De Blieux, D. D.; Simons, E.L.; Chatrath, P.S.

    2009-01-01

    Small mammals are rarely reported from subfossil sites in Madagascar despite their importance for paleoenvironmental reconstruction, especially as it relates to recent ecological changes on the island. We describe the uniquely rich subfossil small mammal fauna from Ankilitelo Cave, southwestern Madagascar. The Ankilitelo fauna is dated to the late Holocene (???500 years ago), documenting the youngest appearances of the extinct giant lemur taxa Palaeopropithecus, Megaladapis, and Archaeolemur, in association with abundant remains of small vertebrates, including bats, tenrecs, carnivorans, rodents, and primates. The Ankilitelo fauna is composed of 34 mammalian species, making it one of the most diverse Holocene assemblages in Madagascar. The fauna comprises the 1 st report of the short-tailed shrew tenrec (Microgale brevicaudata) and the ring-tailed mongoose (Galidia elegans) in southwestern Madagascar. Further, Ankilitelo documents the presence of southwestern species that are rare or that have greatly restricted ranges today, such as Nasolo's shrew tenrec (M. nasoloi), Grandidier's mongoose (Galidictis grandidieri), the narrow-striped mongoose (Mungotictis decemlineata), and the giant jumping rat (Hypogeomys antimena). A simple cause for the unusual small mammal occurrences at Ankilitelo is not obvious. Synergistic interactions between climate change, recent fragmentation and human-initiated degradation of forested habitats, and community-level processes, such as predation, most likely explain the disjunct distributions of the small mammals documented at Ankilitelo. ?? 2009 American Society of Mammalogists.

  18. Which Advisory System to Support Innovation in Conservation Agriculture? The Case of Madagascar's Lake Alaotra

    ERIC Educational Resources Information Center

    Faure, Guy; Penot, Eric; Rakotondravelo, Jean Chrysostome; Ramahatoraka, Haja Andrisoa; Dugue, Patrick; Toillier, Aurelie

    2013-01-01

    Purpose: To promote sustainable agriculture, various development projects are encouraging farmers around Madagascar's Lake Alaotra to adopt conservation agriculture techniques. This article's objective is to analyze the capacity of a project-funded advisory system to accompany such an innovation and to design and implement an advisory method aimed…

  19. Understanding Mortality and the Life of the Ancestors in Rural Madagascar

    ERIC Educational Resources Information Center

    Astuti, Rita; Harris, Paul L.

    2008-01-01

    Across two studies, a wide age range of participants was interviewed about the nature of death. All participants were living in rural Madagascar in a community where ancestral beliefs and practices are widespread. In Study 1, children (8-17 years) and adults (19-71 years) were asked whether bodily and mental processes continue after death. The…

  20. Examining the Environmental Awareness of Children and Adolescents in the Ranomafana Region, Madagascar

    ERIC Educational Resources Information Center

    Korhonen, Kaisa; Lappalainen, Anu

    2004-01-01

    This paper examines children's and adolescents' environmental awareness in rural Madagascar. Two types of school survey among 8- to 21-year-old students and pupils in 18 schools were used for data collection. The objective of this comparative study was to examine the environmental awareness and knowledge of children and adolescents living under…

  1. Which Advisory System to Support Innovation in Conservation Agriculture? The Case of Madagascar's Lake Alaotra

    ERIC Educational Resources Information Center

    Faure, Guy; Penot, Eric; Rakotondravelo, Jean Chrysostome; Ramahatoraka, Haja Andrisoa; Dugue, Patrick; Toillier, Aurelie

    2013-01-01

    Purpose: To promote sustainable agriculture, various development projects are encouraging farmers around Madagascar's Lake Alaotra to adopt conservation agriculture techniques. This article's objective is to analyze the capacity of a project-funded advisory system to accompany such an innovation and to design and implement an advisory method aimed…

  2. Candidatus Phytoplasma malaysianum, a novel taxon associated with virescence and phyllody of Madagascar periwinkle (Catharanthus roseus)

    USDA-ARS?s Scientific Manuscript database

    This study addressed the taxonomic position and group classification of a phytoplasma responsible for virescence and phyllody symptoms in naturally diseased Madagascar periwinkle plants in western Malaysia. Unique regions in the 16S rRNA gene from the Malaysian periwinkle virescence (MaPV) phytopla...

  3. AMS 14C Dates for Extinct Lemurs from Caves in the Ankarana Massif, Northern Madagascar

    NASA Astrophysics Data System (ADS)

    Simons, Elwyn L.; Burney, David A.; Chatrath, Prithijit S.; Godfrey, Laurie R.; Jungers, William L.; Rakotosamimanana, Berthe

    1995-03-01

    An extensive late Quaternary fauna, including many extinct giant lemurs, has been collected recently in a 110+-km system of caves in the Ankarana Massif of northern Madagascar. AMS 14C dates for the acid-insoluble (collagen/gelatin) fraction of bones of the giant lemur Megaladapis (26,150 ± 400 and 12,760 ± 70 yr B.P.) confirm its presence in the area during the late Pleistocene and provide the first Pleistocene 14 C ages from bones of the extinct megafauna of the island. The first date from bones of the recently described extinct Babakotia radofilai (4400 ± 60 yr B.P.) shows that it was present in northern Madagascar in mid-Holocene times. A comparatively recent age of 1020 ± 50 yr B.P. for the extinct Archaeolemur indicates survival of this genus for at least a millennium after the first direct evidence for humans in Madagascar. This suggests that the island's "extinction window" may have represented a longer time span than would have been expected under the Blitzkrieg model of late Quaternary extinctions. A mid-Holocene age (4560 ± 70 yr B.P.) for a bone sample of the small extant lemur Hapalemur simus indicates that the disappearance of this now-restricted species from the Ankarana occurred after this date. New data from the Ankarana and other sites on the island add to the consensus that major biotic changes occurred on Madagascar in the late Holocene.

  4. Ecology and Conservation Status of Indian Ocean Humpback Dolphins (Sousa plumbea) in Madagascar.

    PubMed

    Cerchio, Salvatore; Andrianarivelo, Norbert; Andrianantenaina, Boris

    2015-01-01

    The Indian Ocean humpback dolphin (Sousa plumbea) has been studied in several range states in the Southwest Indian Ocean, however little information exists on populations in Madagascar. Here, we review available literature and describe a study on S. plumbea conducted between 2004 and 2013 on the west coast of Madagascar, involving boat-based field surveys in the southwest and northwest regions, and interview surveys with local fishers from villages along most of the west coast. Field surveys in the southwest region of Anakao/St. Augustine Bay revealed low encounter rates and mean group size, and markedly declining trends in both from 1999 to 2013. Conversely, in the northwest region around Nosy Be and Nosy Iranja, encounter rates were higher, as were mean group sizes, suggesting an apparently more abundant and less impacted population. Interview surveys revealed by-catch of coastal dolphins along the entire west coast, including S. plumbea, as well as other species. Directed hunting, including drive hunts of groups of dolphins, was reported primarily in the southern regions, in the range of the Vezo Malagasy ethnicity; however, there was evidence of hunting starting in one area in the northwest, where hunting dolphins is normally considered taboo for the predominant Sakalava ethnicity. Thus, the conservation status of S. plumbea in Madagascar appears to be spatially heterogeneous, with some areas where the local population is apparently more impacted than others. Conservation measures are recommended to mitigate further decline in the southwest of Madagascar, while protecting habitat and ensuring resilience in the northwest.

  5. Genetics of the pig tapeworm in madagascar reveal a history of human dispersal and colonization.

    PubMed

    Yanagida, Tetsuya; Carod, Jean-François; Sako, Yasuhito; Nakao, Minoru; Hoberg, Eric P; Ito, Akira

    2014-01-01

    An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation.

  6. Understanding Mortality and the Life of the Ancestors in Rural Madagascar

    ERIC Educational Resources Information Center

    Astuti, Rita; Harris, Paul L.

    2008-01-01

    Across two studies, a wide age range of participants was interviewed about the nature of death. All participants were living in rural Madagascar in a community where ancestral beliefs and practices are widespread. In Study 1, children (8-17 years) and adults (19-71 years) were asked whether bodily and mental processes continue after death. The…

  7. Dispersing towards Madagascar: Biogeography and evolution of the Madagascan endemics of the Spermacoceae tribe (Rubiaceae).

    PubMed

    Janssens, Steven B; Groeninckx, Inge; De Block, Petra J; Verstraete, Brecht; Smets, Erik F; Dessein, Steven

    2016-02-01

    Despite the close proximity of the African mainland, dispersal of plant lineages towards Madagascar remains intriguing. The composition of the Madagascan flora is rather mixed and shows besides African representatives, also floral elements of India, Southeast Asia, Australia, and the Neotropics. Due to its proportionally large number of Madagascan endemics, the taxonomically troublesome Spermacoceae tribe is an interesting group to investigate the origin and evolution of the herbaceous Rubiaceae endemic to Madagascar. The phylogenetic position of these endemics were inferred using four plastid gene markers. Age estimates were obtained by expanding the Spermacoceae dataset with representatives of all Rubiaceae tribes. This allowed incorporation of multiple fossil-based calibration points from the Rubiaceae fossil record. Despite the high morphological diversity of the endemic herbaceous Spermacoceae on Madagascar, only two colonization events gave rise to their current diversity. The first clade contains Lathraeocarpa, Phylohydrax and Gomphocalyx, whereas the second Madagascan clade includes the endemic genera Astiella, Phialiphora, Thamnoldenlandia and Amphistemon. The tribe Spermacoceae is estimated to have a Late Eocene origin, and diversified during Oligocene and Miocene. The two Madagascan clades of the tribe originated in the Oligocene and radiated in the Miocene. The origin of the Madagascan Spermacoceae cannot be explained by Gondwanan vicariance but only by means of Cenozoic long distance dispersal events. Interestingly, not only colonization from Africa occurred but also long distance dispersal from the Neotropics shaped the current diversity of the Spermacoceae tribe on Madagascar.

  8. How well suited are maar lakes of Madagascar for palaeoenvironmental multi-proxy reconstructions? - First results from shallow seismic, sedimentological and hydrological investigations in Central and Northwest Madagascar.

    NASA Astrophysics Data System (ADS)

    Daut, Gerhard; Jasmin Krahn, Kim; Rabhobisoa, Jean-Jacques; Ornella Moanazafy, Sergénie; Haberzettl, Torsten; Kasper, Thomas; Mäusbacher, Roland; Schwalb, Antje

    2017-04-01

    Madagascar is well known for its unique flora and fauna which are frequently in the focus of scientific investigations. However, studies on environmental changes in Madagascar linked to Quaternary climatic and/or anthropogenic impact are scarce. The aim of this initial study is to evaluate the potential of maar lakes, situated in different climatic zones of Madagascar, for paleoenvironmental studies and to identify promising coring sites with continuous sediment sequences reaching far back in time. Therefore, in November 2016, a shallow seismic profiling campaign, combined with surface sediment, short gravity core (max. 1.8 m), water and plankton sampling was performed on three target sites. These were two deep maar lakes, i.e., Andraikiba (Central Madagascar, 50m waterdepth) as well as Amparahibe (46,5m waterdepth) and Andampy Ambatoloaka, a shallow (5m waterdepth during low tide) former maar lake now connected to the Ocean (both NW-Madagascar. Vertical water parameter measurements in Lake Amparahibe confirm anoxic bottom conditions, while dissolved oxygen values at the water surface are about 7.9 mg/L (103%). Temperature decreases with depth from 29.3 °C to 27.2 °C, and the lake is slightly alkaline with an electrical conductivity of around 245 µS/cm. Since Andampy Ambatoloaka is connected to the ocean, it shows slightly alkaline conditions as well, electrical conductivity is high ( 57.8 mS/cm) and dissolved oxygen and temperature values are relatively stable at about 8.2 mg/L (104%) and 28.1 °C, respectively. The shallow seismic survey shows an infill with layered sediments of >50 m thickness in Lake Andraikiba. In Lake Amparahibe natural gas in the sediment prevented deeper penetration, however the record shows 10 m of undisturbed, layered sediments in the uppermost part. Sediment cores obtained from both lakes consist of dark brownish to blackish, clayey to silty and partly laminated sediments. High values of magnetic susceptibilities (>1800*10-6 SI) and

  9. Agro-Environmental Determinants of Avian Influenza Circulation: A Multisite Study in Thailand, Vietnam and Madagascar

    PubMed Central

    Paul, Mathilde C.; Gilbert, Marius; Desvaux, Stéphanie; Rasamoelina Andriamanivo, Harena; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Véronique

    2014-01-01

    Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 2004–2005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced. PMID:25029441

  10. Stone tools and foraging in northern Madagascar challenge Holocene extinction models.

    PubMed

    Dewar, Robert E; Radimilahy, Chantal; Wright, Henry T; Jacobs, Zenobia; Kelly, Gwendolyn O; Berna, Francesco

    2013-07-30

    Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar's known occupational history, and thus the time during which people exploited Madagascar's environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. (14)C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton'i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050-1350, by (14)C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. (14)C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact.

  11. Madagascar corals reveal a multidecadal signature of rainfall and river runoff since 1708

    NASA Astrophysics Data System (ADS)

    Grove, C. A.; Zinke, J.; Peeters, F.; Park, W.; Scheufen, T.; Kasper, S.; Randriamanantsoa, B.; McCulloch, M. T.; Brummer, G.-J. A.

    2013-03-01

    Pacific Ocean sea surface temperatures (SST) influence rainfall variability on multidecadal and interdecadal timescales in concert with the Pacific Decadal Oscillation (PDO) and Interdecadal Pacific Oscillation (IPO). Rainfall variations in locations such as Australia and North America are therefore linked to phase changes in the PDO. Furthermore, studies have suggested teleconnections exist between the western Indian Ocean and Pacific Decadal Variability (PDV), similar to those observed on interannual timescales related to the El Niño Southern Oscillation (ENSO). However, as instrumental records of rainfall are too short and sparse to confidently assess multidecadal climatic teleconnections, here we present four coral climate archives from Madagascar spanning up to the past 300 yr (1708-2008) to assess such decadal variability. Using spectral luminescence scanning to reconstruct past changes in river runoff, we identify significant multidecadal and interdecadal frequencies in the coral records, which before 1900 are coherent with Asian-based PDO reconstructions. This multidecadal relationship with the Asian-based PDO reconstructions points to an unidentified teleconnection mechanism that affects Madagascar rainfall/runoff, most likely triggered by multidecadal changes in North Pacific SST, influencing the Asian Monsoon circulation. In the 20th century we decouple human deforestation effects from rainfall-induced soil erosion by pairing luminescence with coral geochemistry. Positive PDO phases are associated with increased Indian Ocean temperatures and runoff/rainfall in eastern Madagascar, while precipitation in southern Africa and eastern Australia declines. Consequently, the negative PDO phase that started in 1998 may contribute to reduced rainfall over eastern Madagascar and increased precipitation in southern Africa and eastern Australia. We conclude that multidecadal rainfall variability in Madagascar and the western Indian Ocean needs to be taken into

  12. Profound and pervasive degradation of Madagascar's freshwater wetlands and links with biodiversity.

    PubMed

    Bamford, Andrew J; Razafindrajao, Felix; Young, Richard P; Hilton, Geoff M

    2017-01-01

    Reflecting a global trend, freshwater wetlands in Madagascar have received little conservation or research attention. Madagascar is a global conservation priority due to its high level of species endemism but most work has focused on protecting forests. For the first time, we investigated the state of wetlands across the country to determine the effects of human disturbance. We conducted a rapid survey of 37 wetlands, using waterbirds and benthic invertebrates as ecological indicators. We recorded nine variables relating to human disturbance, revealing widespread wetland destruction. Principal Components Analysis reduced the nine variables to a single Principal Component (PC) that explained 50% of the dataset variance, demonstrating that different forms of human disturbance are ubiquitous and inseparable. The disturbance PC provides an index of how pristine a lake is and in Generalized Linear Models (GLMs) was significantly inversely related to the number of waterbird species present and the density of Chironomidae. The disturbance PC was estimated for every wetland in a GIS-derived dataset of wetland locations in Madagascar, giving a country-wide frequency distribution of disturbance. To validate the estimated PC values, we used the GLMs to predict the number of endemic bird species at an independent sample of 22 lakes. The predicted values correlated with the observed number of species, demonstrating that our procedure can identify lakes with high biodiversity value. The disturbance PC provides a convenient method for ranking sites, and a country-wide ranking demonstrates that the only near-pristine lakes in Madagascar are small sites that have been preserved by remoteness from human activity and not conservation management. The strategy of conserving high biodiversity remnants is insufficient because existing remnants suffer some degree of degradation and only support small populations of threatened species. Large-scale restoration of degraded wetlands is

  13. In or out-of-Madagascar?--Colonization patterns for large-bodied diving beetles (Coleoptera: Dytiscidae).

    PubMed

    Bukontaite, Rasa; Ranarilalatiana, Tolotra; Randriamihaja, Jacquelin Herisahala; Bergsten, Johannes

    2015-01-01

    High species diversity and endemism within Madagascar is mainly the result of species radiations following colonization from nearby continents or islands. Most of the endemic taxa are thought to be descendants of a single or small number of colonizers that arrived from Africa sometime during the Cenozoic and gave rise to highly diverse groups. This pattern is largely based on vertebrates and a small number of invertebrate groups. Knowledge of the evolutionary history of aquatic beetles on Madagascar is lacking, even though this species-rich group is often a dominant part of invertebrate freshwater communities in both standing and running water. Here we focus on large bodied diving beetles of the tribes Hydaticini and Cybistrini. Our aims with this study were to answer the following questions 1) How many colonization events does the present Malagasy fauna originate from? 2) Did any colonization event lead to a species radiation? 3) Where did the colonizers come from--Africa or Asia--and has there been any out-of-Madagascar event? 4) When did these events occur and were they concentrated to any particular time interval? Our results suggest that neither in Hydaticini nor in Cybistrini was there a single case of two or more endemic species forming a monophyletic group. The biogeographical analysis indicated different colonization histories for the two tribes. Cybistrini required at least eight separate colonization events, including the non-endemic species, all comparatively recent except the only lotic (running water) living Cybister operosus with an inferred colonization at 29 Ma. In Hydaticini the Madagascan endemics were spread out across the tree, often occupying basal positions in different species groups. The biogeographical analyses therefore postulated the very bold hypothesis of a Madagascan origin at a very deep basal node within Hydaticus and multiple out-of-Madagascar dispersal events. This hypothesis needs to be tested with equally intense taxon sampling

  14. Detection of new genetic variants of Betacoronaviruses in Endemic Frugivorous Bats of Madagascar.

    PubMed

    Razanajatovo, Norosoa H; Nomenjanahary, Lalaina A; Wilkinson, David A; Razafimanahaka, Julie H; Goodman, Steven M; Jenkins, Richard K; Jones, Julia P G; Heraud, Jean-Michel

    2015-03-12

    Bats are amongst the natural reservoirs of many coronaviruses (CoVs) of which some can lead to severe infection in human. African bats are known to harbor a range of pathogens (e.g., Ebola and Marburg viruses) that can infect humans and cause disease outbreaks. A recent study in South Africa isolated a genetic variant closely related to MERS-CoV from an insectivorous bat. Though Madagascar is home to 44 bat species (41 insectivorous and 3 frugivorous) of which 34 are endemic, no data exists concerning the circulation of CoVs in the island's chiropteran fauna. Certain Malagasy bats can be frequently found in close contact with humans and frugivorous bats feed in the same trees where people collect and consume fruits and are hunted and consumed as bush meat. The purpose of our study is to detect and identify CoVs from frugivorous bats in Madagascar to evaluate the risk of human infection from infected bats. Frugivorous bats belonging to three species were captured in four different regions of Madagascar. We analyzed fecal and throat swabs to detect the presence of virus through amplification of the RNA-dependent RNA polymerase (RdRp) gene, which is highly conserved in all known coronaviruses. Phylogenetic analyses were performed from positive specimens. From 351 frugivorous bats, we detected 14 coronaviruses from two endemic bats species, of which 13 viruses were identified from Pteropus rufus and one from Eidolon dupreanum, giving an overall prevalence of 4.5%. Phylogenetic analysis revealed that the Malagasy strains belong to the genus Betacoronavirus but form three distinct clusters, which seem to represent previously undescribed genetic lineages. Our findings suggest that CoVs circulate in frugivorous bats of Madagascar, demonstrating the needs to evaluate spillover risk to human populations especially for individuals that hunt and consume infected bats. Possible dispersal mechanisms as to how coronaviruses arrived on Madagascar are discussed.

  15. Introduction of rubella-containing-vaccine to Madagascar: implications for roll-out and local elimination

    PubMed Central

    Wesolowski, Amy; Mensah, Keitly; Brook, Cara E.; Andrianjafimasy, Miora; Winter, Amy; Buckee, Caroline O.; Razafindratsimandresy, Richter; Tatem, Andrew J.; Heraud, Jean-Michel; Metcalf, C. Jessica E.

    2016-01-01

    Few countries in Africa currently include rubella-containing vaccination (RCV) in their immunization schedule. The Global Alliance for Vaccines Initiative (GAVI) recently opened a funding window that has motivated more widespread roll-out of RCV. As countries plan RCV introductions, an understanding of the existing burden, spatial patterns of vaccine coverage, and the impact of patterns of local extinction and reintroduction for rubella will be critical to developing effective programmes. As one of the first countries proposing RCV introduction in part with GAVI funding, Madagascar provides a powerful and timely case study. We analyse serological data from measles surveillance systems to characterize the epidemiology of rubella in Madagascar. Combining these results with data on measles vaccination delivery, we develop an age-structured model to simulate rubella vaccination scenarios and evaluate the dynamics of rubella and the burden of congenital rubella syndrome (CRS) across Madagascar. We additionally evaluate the drivers of spatial heterogeneity in age of infection to identify focal locations where vaccine surveillance should be strengthened and where challenges to successful vaccination introduction are expected. Our analyses indicate that characteristics of rubella in Madagascar are in line with global observations, with an average age of infection near 7 years, and an impact of frequent local extinction with reintroductions causing localized epidemics. Modelling results indicate that introduction of RCV into the routine programme alone may initially decrease rubella incidence but then result in cumulative increases in the burden of CRS in some regions (and transient increases in this burden in many regions). Deployment of RCV with regular supplementary campaigns will mitigate these outcomes. Results suggest that introduction of RCV offers a potential for elimination of rubella in Madagascar, but also emphasize both that targeted vaccination is likely to be

  16. Avian malaria on Madagascar: bird hosts and putative vector mosquitoes of different Plasmodium lineages.

    PubMed

    Schmid, Sandrine; Dinkel, Anke; Mackenstedt, Ute; Tantely, Michaël Luciano; Randrianambinintsoa, Fano José; Boyer, Sébastien; Woog, Friederike

    2017-01-05

    Avian malaria occurs almost worldwide and is caused by Haemosporida parasites (Plasmodium, Haemoproteus and Leucocytozoon). Vectors such as mosquitoes, hippoboscid flies or biting midges are required for the transmission of these parasites. There are few studies about avian malaria parasites on Madagascar but none about suitable vectors. To identify vectors of avian Plasmodium parasites on Madagascar, we examined head, thorax and abdomen of 418 mosquitoes from at least 18 species using a nested PCR method to amplify a 524 bp fragment of the haemosporidian mitochondrial cytochrome b gene. Sequences obtained were then compared with a large dataset of haemosporidian sequences detected in 45 different bird species (n = 686) from the same area in the Maromizaha rainforest. Twenty-one mosquitoes tested positive for avian malaria parasites. Haemoproteus DNA was found in nine mosquitoes (2.15%) while Plasmodium DNA was found in 12 mosquitoes (2.87%). Seven distinct lineages were identified among the Plasmodium DNA samples. Some lineages were also found in the examined bird samples: Plasmodium sp. WA46 (EU810628.1) in the Madagascar bulbul, Plasmodium sp. mosquito 132 (AB308050.1) in 15 bird species belonging to eight families, Plasmodium sp. PV12 (GQ150194.1) in eleven bird species belonging to eight families and Plasmodium sp. P31 (DQ839060.1) was found in three weaver bird species. This study provides the first insight into avian malaria transmission in the Maromizaha rainforest in eastern Madagascar. Five Haemoproteus lineages and seven Plasmodium lineages were detected in the examined mosquitoes. Complete life-cycles for the specialist lineages WA46 and P31 and for the generalist lineages mosquito132 and PV12 of Plasmodium are proposed. In addition, we have identified for the first time Anopheles mascarensis and Uranotaenia spp. as vectors for avian malaria and offer the first description of vector mosquitoes for avian malaria in Madagascar.

  17. Genetic divergence among disjunct populations of three Russula spp. from Africa and Madagascar.

    PubMed

    Kleine, Chris S; McClean, Terry; Miller, Steven L

    2013-01-01

    This study was a preliminary analysis of the genetic structure of the ectomycorrhizal species Russula discopus, R. pseudocarmecina and R. ochraceorivulosa with disjunct distributions in continental Africa and Madagascar. Phylogenetic analyses of the nuclear ITS1/5.8S/ITS2 region and the mitochondrial atp6 gene were performed with specimens from both locations for each species along with a suitable outgroup for each of the three taxa. Additional analyses of the ITS1/5.8S/ITS2 region using the African and Malagasy specimens and additional taxa in the genus Russula also were performed. R. pseudocarmecina and R. discopus both exhibited genetic structure as shown by a relatively high percentage difference in ITS and atp6 sequences, high bootstrap support for African or Malagasy groups and the presence of indels in the ITS sequence that are unique to either Africa or Madagascar. African and Malagasy groups of each species were more closely related to each other than to other taxa in Russula. Genetic structure also existed in populations of R. ochraceorivulosa, but bootstrap support was weaker than in the other two species. In addition, there was less sequence divergence in R. ochraceorivulosa and this species was the only one for which the same atp6 haplotype was found in both Africa and Madagascar. Reciprocal monophyly for all three species was consistent with the hypothesis that the same vicariance event may be responsible for the genetic structure observed here, although shorter branch lengths, lower bootstrap support and the presence of the same atp6 haplotype in Africa and Madagascar for R. ochraceorivulosa suggested slower evolutionary rates or geographical isolation after the other two taxa. In addition to the geological events that separated Africa and Madagascar, environmental changes during the Miocene or later might have had an effect on the distribution of these species.

  18. Agro-environmental determinants of avian influenza circulation: a multisite study in Thailand, Vietnam and Madagascar.

    PubMed

    Paul, Mathilde C; Gilbert, Marius; Desvaux, Stéphanie; Andriamanivo, Harena Rasamoelina; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Véronique

    2014-01-01

    Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 2004-2005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced.

  19. Introduction of rubella-containing-vaccine to Madagascar: implications for roll-out and local elimination.

    PubMed

    Wesolowski, Amy; Mensah, Keitly; Brook, Cara E; Andrianjafimasy, Miora; Winter, Amy; Buckee, Caroline O; Razafindratsimandresy, Richter; Tatem, Andrew J; Heraud, Jean-Michel; Metcalf, C Jessica E

    2016-04-01

    Few countries in Africa currently include rubella-containing vaccination (RCV) in their immunization schedule. The Global Alliance for Vaccines Initiative (GAVI) recently opened a funding window that has motivated more widespread roll-out of RCV. As countries plan RCV introductions, an understanding of the existing burden, spatial patterns of vaccine coverage, and the impact of patterns of local extinction and reintroduction for rubella will be critical to developing effective programmes. As one of the first countries proposing RCV introduction in part with GAVI funding, Madagascar provides a powerful and timely case study. We analyse serological data from measles surveillance systems to characterize the epidemiology of rubella in Madagascar. Combining these results with data on measles vaccination delivery, we develop an age-structured model to simulate rubella vaccination scenarios and evaluate the dynamics of rubella and the burden of congenital rubella syndrome (CRS) across Madagascar. We additionally evaluate the drivers of spatial heterogeneity in age of infection to identify focal locations where vaccine surveillance should be strengthened and where challenges to successful vaccination introduction are expected. Our analyses indicate that characteristics of rubella in Madagascar are in line with global observations, with an average age of infection near 7 years, and an impact of frequent local extinction with reintroductions causing localized epidemics. Modelling results indicate that introduction of RCV into the routine programme alone may initially decrease rubella incidence but then result in cumulative increases in the burden of CRS in some regions (and transient increases in this burden in many regions). Deployment of RCV with regular supplementary campaigns will mitigate these outcomes. Results suggest that introduction of RCV offers a potential for elimination of rubella in Madagascar, but also emphasize both that targeted vaccination is likely to be

  20. Two new eimerians (Apicomplexa) from insectivorous mammals in Madagascar.

    PubMed

    Couch, Lee; Laakkonen, Juha; Goodman, Steven; Duszynski, Donald W

    2011-04-01

    Fecal samples from 126 insectivorous mammals in Madagascar were collected between spring 1999 and fall 2001. In the Afrosoricida, 21 species in 5 genera were sampled, including 17 species of Microgale (31/96, 32% infected), Hemicentetes semispinosus (1/2, 50%), Oryzorictes hova (1/5, 20%), Setifer setosus (8/13, 61.5%), and Tenrec ecaudatus (5/8, 62.5%); in the Soricomorpha, only Suncus murinus was examined and 1/2 (50%) were infected. Two morphotypes of eimeriid oocysts, representing 2 presumptive new species, were found in 47 (37%) infected animals; only 2 afrosoricid hosts (2% of all hosts, 4% of infected hosts) had both oocyst morphotypes. Sporulated oocysts of the first morphotype, Eimeria tenrececaudata n. sp., are subspheroidal, 18.8 × 17.4 (17-22 × 15-20), with a length∶width ratio (L/W) of 1.1 (1.0-1.2); they lack a micropyle but may contain 0-2 polar granules and a single, small round oocyst residuum, 3 × 2.3. Sporocysts are lemon-shaped, 9.9 × 6.6 (9-11 × 5-8), with a L/W of 1.5 (1.2-2.0); they have a prominent, slightly flattened Stieda body and a substieda body but lack a parastieda body. The sporocyst residuum consists of only a few granules between the sporozoites, which are sausage-shaped and have a large posterior refractile body. Oocysts of the second morphotype, Eimeria setifersetosa n. sp. are spheroidal to subspheroidal, 30.1 × 28.6 (27-34 × 25-34), with a L/W of 1.1 (1.0-1.2); they lack both micropyle and oocyst residuum, but 1-2 polar granules are usually present. Sporocysts are subspheroidal to broadly ellipsoidal, 9.6 × 7.3 (9-11 × 6-8), with a L/W of 1.3 (1.1-1.7); they have a broad Stieda body, lack sub- and parastieda bodies, and have a residuum of a few granules scattered throughout the sporocyst. Sporozoites were not clearly defined, but what seemed to be a single large refractile body is seen, presumably in each sporozoite.

  1. Geological evolution of the Antongil Craton, NE Madagascar

    USGS Publications Warehouse

    Schofield, D.I.; Thomas, Ronald J.; Goodenough, K.M.; De Waele, B.; Pitfield, P.E.J.; Key, R.M.; Bauer, W.; Walsh, G.J.; Lidke, D.J.; Ralison, A.V.; Rabarimanana, M.; Rafahatelo, J.-M.; Randriamananjara, T.

    2010-01-01

    The Antongil Craton, along with the Masora and Antananarivo cratons, make up the fundamental Archaean building blocks of the island of Madagascar. They were juxtaposed during the late-Neoproterozoic to early Palaeozoic assembly of Gondwana. In this paper we give a synthesis of the geology of the Antongil Craton and present previously published and new geochemical and U-Pb zircon analyses to provide an event history for its evolution.The oldest rocks in the Antongil Craton form a nucleus of tonalitic gneiss, characteristic of Palaeo-Mesoarchaean cratons globally, including phases dated between 3320 ?? 14. Ma to 3231 ?? 6. Ma and 3187 ?? 2. Ma to 3154 ?? 5. Ma. A series of mafic dykes was intruded into the Mesoarchaean tonalites and a sedimentary succession was deposited on the craton prior to pervasive deformation and migmatisation of the region. The age of deposition of the metasediments has been constrained from a volcanic horizon to around 3178 ?? 2. Ma and subject to migmatisation at around 2597 ?? 49. Ma. A subsequent magmatic episode generated voluminous, weakly foliated granitic rocks, that also included additions from both reworked older crustal material and younger source components. An earlier granodiorite-dominated assemblage, dated between 2570 ?? 18. Ma and 2542 ?? 5. Ma, is largely exposed in xenoliths and more continuously in the northern part of the craton, while a later monzogranite-dominated phase, dated between 2531 ?? 13. Ma and 2513 ?? 0.4. Ma is more widely developed. Together these record the stabilisation of the craton, attested to by the intrusion of a younger dyke swarm, the age of which is constrained by a sample of metagabbro dated at 2147 ?? 6. Ma, providing the first evidence for Palaeoproterozoic rocks from the Antongil Craton.The youngest events recorded in the isotopic record of the Antongil Craton are reflected in metamorphism, neocrystallisation and Pb-loss at 792 ?? 130. Ma to 763 ?? 13. Ma and 553 ?? 68. Ma. These events are

  2. Determinants of condom use among youth in Madagascar.

    PubMed

    Meekers, Dominique; Silva, Martha; Klein, Megan

    2006-05-01

    The objective of this study was to identify the key determinants of condom use with regular and casual partners among youth in Madagascar. Data stem from a reproductive health survey conducted in October-December 2000 among a representative sample of 2440 youth aged 15-24 living in Toamasina province. Following theoretical models of behaviour change, logistic regression was used to assess the effect of AIDS awareness,personal risk perception, condom access, perceived condom effectiveness,self-efficacy and social support on condom use. Among sexually experienced youth, only about four in ten males and two in ten females have ever used condoms. Fewer than 15% of youth used a condom in last intercourse with their regular partner. Whether youth will try condoms appears to depend largely on the perceived effectiveness of condoms for family planning, access to a nearby condom source, parental support for condom use, and patterns of risky sexual behaviour. Young males' likelihood of using a condom with a regular partner increases significantly if they perceive condoms to be effective for family planning (OR=11.4; p=0.019). For females, it increases with level of self-efficacy (OR=2 1; p=0.042) and having discussed HIV prevention with someone in the last year (OR=2.8; p=0.022). Among males,condom use with casual partners is significantly higher among those who perceive themselves to be at high risk of sexually transmitted infections(OR=2.3; p=0.014), who believe condoms are effective for family planning(OR=2.8; p=0.048), who have good access to condoms (OR=2.9; p=0.002)and who perceive their parents support condom use (OR=1-7; p=0.048). In conclusion, very few youth in Toamasina are using condoms, highlighting the need to continue and expand adolescent reproductive health interventions. In this low HIV prevalence setting, it is important for these programmes to emphasize that condoms are effective for both pregnancy prevention and STI/HIV prevention.

  3. Revision of the genera Hovadelium Ardoin and Mimolaena Ardoin (Coleoptera, Tenebrionidae, Laenini) from Madagascar, with remarks on tribal assignment1

    PubMed Central

    Schawaller, Wolfgang

    2013-01-01

    Abstract The genera Hovadelium Ardoin, 1961 and Mimolaena Ardoin, 1961, endemic in Madagascar, are revised and assigned to the tribe Laenini Seidlitz, 1896 (subfamily Lagriinae Latreille, 1825). New species: Hovadelium ardoini sp. n., Hovadelium bremeri sp. n. and Mimolaena janaki sp. n. An identification key is compiled for all taxa. Distribution of Hovadelium (5 species) and Mimolaena (3 species) is mapped. The congeners might be indicator species for the highly endangered mature forests in Madagascar. PMID:24039536

  4. Revision of the genera Hovadelium Ardoin and Mimolaena Ardoin (Coleoptera, Tenebrionidae, Laenini) from Madagascar, with remarks on tribal assignment.

    PubMed

    Schawaller, Wolfgang

    2013-01-01

    The genera Hovadelium Ardoin, 1961 and Mimolaena Ardoin, 1961, endemic in Madagascar, are revised and assigned to the tribe Laenini Seidlitz, 1896 (subfamily Lagriinae Latreille, 1825). New species: Hovadelium ardoini sp. n., Hovadelium bremeri sp. n. and Mimolaena janaki sp. n. An identification key is compiled for all taxa. Distribution of Hovadelium (5 species) and Mimolaena (3 species) is mapped. The congeners might be indicator species for the highly endangered mature forests in Madagascar.

  5. Seismic anisotropy of the lithosphere-asthenosphere system beneath southern Madagascar

    NASA Astrophysics Data System (ADS)

    Reiss, Miriam Christina; Rümpker, Georg; Tilmann, Frederik; Yuan, Xiaohui; Josiane Rindraharisaona, Elisa

    2015-04-01

    Madagascar is considered as a key region with respect to the assembly and break-up of the supercontinent Gondwana. Following the collision between East- and West-Gondwana (~700-650 Ma), its position was central to the Panafrican orogenesis. Madagascar then separated from East Africa and later from the Indian and Antarctic plates until these processes came to a halt about 69 Ma ago. Today, Madagascar consists of different tectonic units; the eastern parts (two thirds of the island) are composed mainly of Precambian rocks, whereas the western part is dominated by sedimentary deposits. Furthermore, southern Madagascar is characterized by several NS to NW-SE trending shear zones. Madagascar has been the target of a number of geological studies, but seismological investigations of the presumed complex lithosphere-asthenosphere system and of deeper upper-mantle structures are sparse. To increase our understanding of these structures and related tectonic processes, we installed a dense temporary seismic network in southern Madagascar. It consisted of 25 broadband and 25 short-period stations, which were in operation for up to 2 years between 2012 and 2014. The broadband stations crossed the island along an east-west profile; the eastern section was supplemented by a network of short-period stations. Here we present results from shear-wave splitting analyses to infer the seismic anisotropy of the lithosphere-asthenosphere system in response to deformational processes. The polarization of the fast shear wave and the delay time between the fast and slow waves provide constraints on the anisotropic fabric. For our study, we use SKS-phases from up to 12 events recorded at the temporary stations and from 10 events at the permanent GEOFON station VOI. We first apply a single-event splitting analysis by minimizing the transverse component. For stations that do not show a significant azimuthal dependence of the splitting parameters, we also apply a joint inversion involving all

  6. How Effective Have Thirty Years of Internationally Driven Conservation and Development Efforts Been in Madagascar?

    PubMed

    Waeber, Patrick O; Wilmé, Lucienne; Mercier, Jean-Roger; Camara, Christian; Lowry, Porter P

    2016-01-01

    Conservation and development are intricately linked. The international donor community has long provided aid to tropical countries in an effort to alleviate poverty and conserve biodiversity. While hundreds of millions of $ have been invested in over 500 environmental-based projects in Madagascar during the period covered by a series of National Environmental Action Plans (1993-2008) and the protected areas network has expanded threefold, deforestation remains unchecked and none of the eight Millennium Development Goals (MDGs) established for 2000-2015 were likely be met. Efforts to achieve sustainable development had failed to reduce poverty or deliver progress toward any of the MDGs. Cross-sectorial policy adjustments are needed that (i) enable and catalyze Madagascar's capacities rather than deepening dependency on external actors such as the World Bank, the International Monetary Fund and donor countries, and that (ii) deliver improvements to the livelihoods and wellbeing of the country's rural poor.

  7. Deforestation history of the eastern rain forests of Madagascar from satellite images

    SciTech Connect

    Green, G.M.; Sussman, R.W. )

    1990-04-13

    Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain forest remained, representing only 50% of the 7.6 million hectares existing in 1950 and 34% of the estimated original extent (11.2 million hectares). Between 1950 and 1985, the rate of deforestation averaged 111,000 hectares per year. Deforestation was most rapid in areas with low topographic relief and high population density. If cutting of forests continues at the same pace, only forests on the steepest slopes will survive the next 35 years.

  8. A likely microendemic new species of terrestrial iguana, genus Chalarodon, from Madagascar.

    PubMed

    Miralles, Aurelien; Glaw, Frank; Ratsoavina, Fanomezana M; Vences, Miguel

    2015-04-09

    A new species of the hitherto monotypic genus Chalarodon is described from southern Madagascar and a lectotype (ZMB 4360) is designated for C. madagascariensis Peters, 1854. The new species of terrestrial iguana, Chalarodon steinkampi sp. nov., is defined by several morphological characters and by concordant differentiation in mitochondrial and nuclear DNA with >5% uncorrected pairwise genetic distance in the 16S rRNA gene. It can be most clearly recognized by the presence of smooth (vs. keeled) gular and ventral scales, a spotted pattern extending from flanks onto belly, and an unpigmented throat. The new species is known from only a small area between the villages of Amboasary Sud and Esomony, located west of the Andohahela Massif, while C. madagascariensis appears to be widespread over much of southern and western Madagascar. We highlight the need for further exploration of this unprotected region which might host several other microendemic species.

  9. Discovery of an island population of dwarf lemurs (Cheirogaleidae: Cheirogaleus) on Nosy Hara, far northern Madagascar.

    PubMed

    Gardner, Charlie J; Jasper, Louise D

    2015-10-01

    The species-level diversity of Madagascar's lemurs has increased hugely over the last two decades, growing from 32 species in 1994 to 102 species in 2014. This growth is primarily due to the application of molecular phylogenetic analyses and the phylogenetic species concept to known populations, and few previously unknown lemur populations have been discovered during this time. We report on a new population of dwarf lemurs (Cheirogaleus sp.) from Nosy Hara, a 312-ha island in far northern Madagascar, which constitutes the northernmost distribution record for the genus. The dwarf lemurs appeared to show two characteristics of island populations-insular dwarfism and predator naïveté-that suggest a long isolation, and may thus represent an undescribed taxon. If this is the case, the dwarf lemurs of Nosy Hara are probably one of the rarest primate taxa on Earth.

  10. Epidemiologic features of four successive annual outbreaks of bubonic plague in Mahajanga, Madagascar.

    PubMed

    Boisier, Pascal; Rahalison, Lila; Rasolomaharo, Monique; Ratsitorahina, Maherisoa; Mahafaly, Mahafaly; Razafimahefa, Maminirana; Duplantier, Jean-Marc; Ratsifasoamanana, Lala; Chanteau, Suzanne

    2002-03-01

    From 1995 to 1998, outbreaks of bubonic plague occurred annually in the coastal city of Mahajanga, Madagascar. A total of 1,702 clinically suspected cases of bubonic plague were reported, including 515 laboratory confirmed by Yersinia pestis isolation (297), enzyme-linked immunosorbent assay, or both. Incidence was higher in males and young persons. Most buboes were inguinal, but children had a higher frequency of cervical or axillary buboes. Among laboratory-confirmed hospitalized patients, the case-fatality rate was 7.9%, although all Y. pestis isolates were sensitive to streptomycin, the recommended antibiotic. In this tropical city, plague outbreaks occur during the dry and cool season. Most cases are concentrated in the same crowded and unsanitary districts, a result of close contact among humans, rats, and shrews. Plague remains an important public health problem in Madagascar, and the potential is substantial for spread to other coastal cities and abroad.

  11. Deforestation history of the eastern rain forests of madagascar from satellite images.

    PubMed

    Green, G M; Sussman, R W

    1990-04-13

    Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain forest remained, representing only 50 percent of the 7.6 million hectares existing in 1950 and 34 percent of the estimated orignal extent (11.2 million hectares). Between 1950 and 1985, the rate of deforestation averaged 111,000 hectares per year. Deforestation was most rapid in areas with low topographic relief and high population density. If cutting of forests continues at the same pace, only forests on the steepest slopes will survive the next 35 years.

  12. Epidemiologic Features of Four Successive Annual Outbreaks of Bubonic Plague in Mahajanga, Madagascar

    PubMed Central

    Rahalison, Lila; Rasolomaharo, Monique; Ratsitorahina, Maherisoa; Mahafaly, Mahafaly; Razafimahefa, Maminirana; Duplantier, Jean-Marc; Ratsifasoamanana, Lala; Chanteau, Suzanne

    2002-01-01

    From 1995 to 1998, outbreaks of bubonic plague occurred annually in the coastal city of Mahajanga, Madagascar. A total of 1,702 clinically suspected cases of bubonic plague were reported, including 515 laboratory confirmed by Yersinia pestis isolation (297), enzyme-linked immunosorbent assay, or both. Incidence was higher in males and young persons. Most buboes were inguinal, but children had a higher frequency of cervical or axillary buboes. Among laboratory-confirmed hospitalized patients, the case-fatality rate was 7.9%, although all Y. pestis isolates were sensitive to streptomycin, the recommended antibiotic. In this tropical city, plague outbreaks occur during the dry and cool season. Most cases are concentrated in the same crowded and insanitary districts, a result of close contact among humans, rats, and shrews. Plague remains an important public health problem in Madagascar, and the potential is substantial for spread to other coastal cities and abroad. PMID:11927030

  13. Community management of natural resources: a case study from Ankarafantsika National Park, Madagascar.

    PubMed

    Aymoz, Benoît G P; Randrianjafy, Vololomboahangy R; Randrianjafy, Zarasoa J N; Khasa, Damase P

    2013-10-01

    We analyzed the management, resource use and conservation of the Ankarafantsika National Park (Madagascar) to develop a management plan, which provides a sustainable development strategy of the area while empowering the local residents. Using qualitative methodology we performed interviews with villagers and local organizations to assess the park's successes and failures from local stakeholders' perspectives. People living in a village with a permanent Madagascar National Parks (MNP) agent are more favorable to and supportive of the park conservation. People living in the park are supportive but are more divided. On the other hand, people living on the periphery of the park see conservation as more of a burden. Strategies like more equitable distribution of wealth, environment improvement and decentralization of power are discussed to achieve a more sustainable management plan based on community natural resources management. Short-term, medium, and long-term interventions from park authorities are needed to ensure the cooperation of local people in conservation endeavors.

  14. Laboratory Surveillance of Rabies in Humans, Domestic Animals, and Bats in Madagascar from 2005 to 2010

    PubMed Central

    Reynes, Jean-Marc; Andriamandimby, Soa Fy; Razafitrimo, Girard Marcelin; Razainirina, Josette; Jeanmaire, Elisabeth Marie; Bourhy, Hervé; Heraud, Jean-Michel

    2011-01-01

    Background. Rabies virus (RABV) has circulated in Madagascar at least since the 19th century. Objectives. To assess the circulation of lyssavirus in the island from 2005 to 2010. Materials and Methods. Animal (including bats) and human samples were tested for RABV and other lyssavirus using antigen, ribonucleic acid (RNA), and antibodies detection and virus isolation. Results. Half of the 437 domestic or tame wild terrestrial mammal brains tested were found RABV antigen positive, including 54% of the 341 dogs tested. This percentage ranged from 26% to 75% across the period. Nine of the 10 suspected human cases tested were laboratory confirmed. RABV circulation was confirmed in 34 of the 38 districts sampled. No lyssavirus RNA was detected in 1983 bats specimens. Nevertheless, antibodies against Lagos bat virus were detected in the sera of 12 among 50 Eidolon dupreanum specimens sampled. Conclusion. More than a century after the introduction of the vaccine, rabies still remains endemic in Madagascar. PMID:21991442

  15. Breakup of pangaea and isolation of relict mammals in australia, South america, and madagascar.

    PubMed

    Fooden, J

    1972-02-25

    The composition of aboriginal land mammal faunas in Australia and New Guinea (prototherians and metatherians), South America (metatherians and eutherians) and Madagascar (eutherians only) is reconsidered in light of continental drift reconstructions of Mesozoic-Tertiary world paleogeography It is proposed that these three faunas represent successively detached samples of the evolving world mammal fauna as it existed when each of these land masses became faunally isolated from the rest of the world as a result of the progressive fragmentation of Pangaea. Isolation of aboriginal prototherians and metatherians in Australia and New Guinea may date from the Upper JurassicLower Cretaceous; isolation of aboriginal metatherians and eutherians in South America may date from the Middle Cretaceous-Upper Cretaceous; isolation of aboriginal eutherians in Madagascar may date from the Paleocene-Eocene.

  16. Intracoelomic anaplastic sarcoma in an intersex Madagascar tree boa (Sanzinia madagascariensis).

    PubMed

    Sharpe, Sam; Lamm, Catherine G; Killick, Rowena

    2013-01-01

    An adult Madagascar tree boa (Sanzinia madagascariensis) underwent coeliotomy for investigation of a coelomic mass. At surgery, a large mass originating from the peri-pancreatic adipose tissue and involving the gall bladder was removed. The snake did not recover from general anesthesia. A complete postmortem was performed, and samples were submitted to the University of Glasgow for histopathology. On histological examination, the mass was composed of adipose tissue infiltrated with a poorly demarcated spindle cell neoplasm. The neoplastic cells were highly pleomorphic with abundant cytoplasm and frequent clear cytoplasmic vacuoles, suggestive of adipocyte origin. Immunohistochemical characterization of the mass was inconclusive. Metastatic neoplastic cells were present within vessels in the liver, lungs, and brain. As an incidental finding, the gonads contained both maturing ovarian follicles and seminiferous tubules with intact germinal epithelium and evidence of spermatogenesis, along with other features of male and female gonad anatomy. The current report describes a rare neoplasm in snakes within an intersex Madagascar tree boa.

  17. Laboratory surveillance of rabies in humans, domestic animals, and bats in madagascar from 2005 to 2010.

    PubMed

    Reynes, Jean-Marc; Andriamandimby, Soa Fy; Razafitrimo, Girard Marcelin; Razainirina, Josette; Jeanmaire, Elisabeth Marie; Bourhy, Hervé; Heraud, Jean-Michel

    2011-01-01

    Background. Rabies virus (RABV) has circulated in Madagascar at least since the 19th century. Objectives. To assess the circulation of lyssavirus in the island from 2005 to 2010. Materials and Methods. Animal (including bats) and human samples were tested for RABV and other lyssavirus using antigen, ribonucleic acid (RNA), and antibodies detection and virus isolation. Results. Half of the 437 domestic or tame wild terrestrial mammal brains tested were found RABV antigen positive, including 54% of the 341 dogs tested. This percentage ranged from 26% to 75% across the period. Nine of the 10 suspected human cases tested were laboratory confirmed. RABV circulation was confirmed in 34 of the 38 districts sampled. No lyssavirus RNA was detected in 1983 bats specimens. Nevertheless, antibodies against Lagos bat virus were detected in the sera of 12 among 50 Eidolon dupreanum specimens sampled. Conclusion. More than a century after the introduction of the vaccine, rabies still remains endemic in Madagascar.

  18. Temporal phylogeography of Yersinia pestis in Madagascar: Insights into the long-term maintenance of plague.

    PubMed

    Vogler, Amy J; Andrianaivoarimanana, Voahangy; Telfer, Sandra; Hall, Carina M; Sahl, Jason W; Hepp, Crystal M; Centner, Heather; Andersen, Genevieve; Birdsell, Dawn N; Rahalison, Lila; Nottingham, Roxanne; Keim, Paul; Wagner, David M; Rajerison, Minoarisoa

    2017-09-01

    Yersinia pestis appears to be maintained in multiple, geographically separate, and phylogenetically distinct subpopulations within the highlands of Madagascar. However, the dynamics of these locally differentiated subpopulations through time are mostly unknown. To address that gap and further inform our understanding of plague epidemiology, we investigated the phylogeography of Y. pestis in Madagascar over an 18 year period. We generated whole genome sequences for 31 strains and discovered new SNPs that we used in conjunction with previously identified SNPs and variable-number tandem repeats (VNTRs) to genotype 773 Malagasy Y. pestis samples from 1995 to 2012. We mapped the locations where samples were obtained on a fine geographic scale to examine phylogeographic patterns through time. We identified 18 geographically separate and phylogenetically distinct subpopulations that display spatial and temporal stability, persisting in the same locations over a period of almost two decades. We found that geographic areas with higher levels of topographical relief are associated with greater levels of phylogenetic diversity and that sampling frequency can vary considerably among subpopulations and from year to year. We also found evidence of various Y. pestis dispersal events, including over long distances, but no evidence that any dispersal events resulted in successful establishment of a transferred genotype in a new location during the examined time period. Our analysis suggests that persistent endemic cycles of Y. pestis transmission within local areas are responsible for the long term maintenance of plague in Madagascar, rather than repeated episodes of wide scale epidemic spread. Landscape likely plays a role in maintaining Y. pestis subpopulations in Madagascar, with increased topographical relief associated with increased levels of localized differentiation. Local ecological factors likely affect the dynamics of individual subpopulations and the associated

  19. A new genus and species of freshwater crab from Madagascar (Decapoda, Brachyura, Potamoidea, Potamonautidae).

    PubMed

    Meyer, Kirstin S; Cumberlidge, Neil; Koppin, Jennifer C

    2014-11-12

    A new genus and species of freshwater crab is described from Madagascar. The new species is morphologically closest to the three species of the genus Foza Reed & Cumberlidge, 2006, but can easily be distinguished by having a completely smooth carapace with an unarmed anterolateral margin and a mandible with a distinctly shortened anterior lobe. This unusual suite of characters is sufficient to warrant the recognition of a new monotypic genus to accommodate this species.

  20. Comprehensive Red List Assessment Reveals Exceptionally High Extinction Risk to Madagascar Palms

    PubMed Central

    Rakotoarinivo, Mijoro; Dransfield, John; Bachman, Steven P.; Moat, Justin; Baker, William J.

    2014-01-01

    The establishment of baseline IUCN Red List assessments for plants is a crucial step in conservation planning. Nowhere is this more important than in biodiversity hotspots that are subject to significant anthropogenic pressures, such as Madagascar. Here, all Madagascar palm species are assessed using the IUCN Red List categories and criteria, version 3.1. Our results indicate that 83% of the 192 endemic species are threatened, nearly four times the proportion estimated for plants globally and exceeding estimates for all other comprehensively evaluated plant groups in Madagascar. Compared with a previous assessment in 1995, the number of Endangered and Critically Endangered species has substantially increased, due to the discovery of 28 new species since 1995, most of which are highly threatened. The conservation status of most species included in both the 1995 and the current assessments has not changed. Where change occurred, more species have moved to lower threat categories than to higher categories, because of improved knowledge of species and their distributions, rather than a decrease in extinction risk. However, some cases of genuine deterioration in conservation status were also identified. Palms in Madagascar are primarily threatened by habitat loss due to agriculture and biological resource use through direct exploitation or collateral damage. The recent extension of Madagascar’s protected area network is highly beneficial for palms, substantially increasing the number of threatened species populations included within reserves. Notably, three of the eight most important protected areas for palms are newly designated. However, 28 threatened and data deficient species are not protected by the expanded network, including some Critically Endangered species. Moreover, many species occurring in protected areas are still threatened, indicating that threatening processes persist even in reserves. Definitive implementation of the new protected areas combined

  1. Neoproterozoic extension in the greater dharwar craton: A reevaluation of the "betsimisaraka suture" in madagascar

    USGS Publications Warehouse

    Tucker, R.D.; Roig, J.-Y.; Delor, C.; Amlin, Y.; Goncalves, P.; Rabarimanana, M.H.; Ralison, A.V.; Belcher, R.W.

    2011-01-01

    The Precambrian shield of Madagascar is reevaluated with recently compiled geological data and new U-Pb sensitive high-resolution ion microprobe (SHRIMP) geochronology. Two Archean domains are recognized: the eastern Antongil-Masora domain and the central Antananarivo domain, the latter with distinctive belts of metamafic gneiss and schist (Tsaratanana Complex). In the eastern domain, the period of early crust formation is extended to the Paleo-Mesoarchean (3.32-3.15 Ga) and a supracrustal sequence (Fenerivo Group), deposited at 3.18 Ga and metamorphosed at 2.55 Ga, is identified. In the central domain, a Neoarchean period of high-grade metamorphism and anatexis that affected both felsic (Betsiboka Suite) and mafic gneisses (Tsaratanana Complex) is documented. We propose, therefore, that the Antananarivo domain was amalgamated within the Greater Dharwar Craton (India + Madagascar) by a Neoarchean accretion event (2.55-2.48 Ga), involving emplacement of juvenile igneous rocks, high-grade metamorphism, and the juxtaposition of disparate belts of mafic gneiss and schist (metagreenstones). The concept of the "Betsimisaraka suture" is dispelled and the zone is redefined as a domain of Neoproterozoic metasedimentary (Manampotsy Group) and metaigneous rocks (Itsindro-Imorona Suite) formed during a period of continental extension and intrusive igneous activity between 840 and 760 Ma. Younger orogenic convergence (560-520 Ma) resulted in east-directed overthrusting throughout south Madagascar and steepening with local inversion of the domain in central Madagascar. Along part of its length, the Manampotsy Group covers the boundary between the eastern and central Archean domains and is overprinted by the Angavo-Ifanadiana high-strain zone that served as a zone of crustal weakness throughout Cretaceous to Recent times.

  2. [Installation of a local information network: case of Pasteur Institute of Madagascar].

    PubMed

    Moustache, C; Rakotondrainy, S; Rabenaivo, C

    1996-01-01

    The development of computer networks, especially Internet, leads to a new way of working organization. Internet mail represents a real progress in communication management for institutions far away from northern collaborating centres such as Institut Pasteur de Madagascar. The resources sharing capacities (hard disks, printers, back-up systems) induce important economies. Thus, the installation of an Ethernet network within the establishment is completely justified.

  3. Three new species of the genus Exphora Signoret, 1860 (Hemiptera, Fulgoromorpha, Tropiduchidae) from Madagascar.

    PubMed

    Junkiert, Łukasz; Walczak, Marcin

    2015-03-04

    Three new species of the genus Exphora Signoret, 1860 (Hemiptera, Fulgoromorpha: Tropiduchidae) are described from Madagascar: E. constanti sp. n., E. stroinskii sp. n. and E. ambatolaonaensis sp. n. The male genitalia are described for the first time in this genus. The male genitalia, head and fore wing of the new species are illustrated with photos of habitus provided. Key to the known species of Exphora is given.

  4. First full genome sequence of a human enterovirus a120, isolated in madagascar.

    PubMed

    Razafindratsimandresy, Richter; Joffret, Marie-Line; Delpeyroux, Francis; Heraud, Jean-Michel

    2014-06-19

    We report the first complete genome sequence of an enterovirus isolate belonging to the human enterovirus A species of the Picornaviridae family and to type A120 (EV-A120). The EV-A120 isolate MAD-2741-11 was obtained from the stool of a healthy child living on Madagascar Island. The isolate genome was amplified by a reverse transcription-PCR method, and the consensus sequence was determined. Copyright © 2014 Razafindratsimandresy et al.

  5. First Full Genome Sequence of a Human Enterovirus A120, Isolated in Madagascar

    PubMed Central

    Joffret, Marie-Line; Delpeyroux, Francis; Heraud, Jean-Michel

    2014-01-01

    We report the first complete genome sequence of an enterovirus isolate belonging to the human enterovirus A species of the Picornaviridae family and to type A120 (EV-A120). The EV-A120 isolate MAD-2741-11 was obtained from the stool of a healthy child living on Madagascar Island. The isolate genome was amplified by a reverse transcription-PCR method, and the consensus sequence was determined. PMID:24948760

  6. Vertical transmission as the key to the colonization of Madagascar by fungus-growing termites?

    PubMed Central

    Nobre, T.; Eggleton, P.; Aanen, D. K.

    2010-01-01

    The mutualism between fungus-growing termites (Macrotermitinae) and their mutualistic fungi (Termitomyces) began in Africa. The fungus-growing termites have secondarily colonized Madagascar and only a subset of the genera found in Africa is found on this isolated island. Successful long-distance colonization may have been severely constrained by the obligate interaction of the termites with fungal symbionts and the need to acquire these symbionts secondarily from the environment for most species (horizontal symbiont transmission). Consistent with this hypothesis, we show that all extant species of fungus-growing termites of Madagascar are the result of a single colonization event of termites belonging to one of the only two groups with vertical symbiont transmission, and we date this event at approximately 13 Mya (Middle/Upper Miocene). Vertical symbiont transmission may therefore have facilitated long-distance dispersal since both partners disperse together. In contrast to their termite hosts, the fungal symbionts have colonized Madagascar multiple times, suggesting that the presence of fungus-growing termites may have facilitated secondary colonizations of the symbiont. Our findings indicate that the absence of the right symbionts in a new environment can prevent long-distance dispersal of symbioses relying on horizontal symbiont acquisition. PMID:19828546

  7. A molecular phylogeny of four endangered Madagascar tortoises based on MtDNA sequences.

    PubMed

    Caccone, A; Amato, G; Gratry, O C; Behler, J; Powell, J R

    1999-06-01

    Four of the five tortoise species in Madagascar, Pyxis arachnoides, P. planicauda, Geochelone radiata, and G. yniphora, are endemic and on the verge of extinction. Their phylogenetic relationships remain controversial and unresolved. Here we address the phylogeny of this group using DNA sequences for the 12S and 16S rDNA and cyt b genes in mitochondrial DNA. As outgroups we used two species of Geochelone, pardalis (mainland Africa) and nigra (Galápagos), as well as a more distant North American tortoise, Gopherus polyphemus. We conclude that the two Pyxis species are sister taxa and are imbedded in the genus Geochelone, rendering this latter genus paraphyletic. There is moderate support for the sister status of the two Madagascar Geochelone and for the monophyletic origin of all four endemics, suggesting a single colonization of the island. The separation of Madagascar from other land masses (90-165 mya) predates the origin of the endemic tortoises (estimated to be 14-22 mya). This suggests founding by rafting, a process known to have occurred with other tortoises. The derived morphological divergence of the Pyxis species in a relatively short period of time (13-20 my) stands in contrast to the notoriously slow rate of morphological evolution in most lineages of Chelonia.

  8. Detecting cryptic speciation in the widespread and morphologically conservative carpet chameleon (Furcifer lateralis) of Madagascar.

    PubMed

    Florio, A M; Ingram, C M; Rakotondravony, H A; Louis, E E; Raxworthy, C J

    2012-07-01

    Species delimitation within recently evolved groups can be challenging because species may be difficult to distinguish morphologically. Following the General Lineage Concept, we apply a multiple evidence approach to assess species limits within the carpet chameleon Furcifer lateralis, which is endemic to Madagascar and exported in large numbers for the pet trade. Cryptic speciation within F. lateralis was considered likely because this species (1) has a vast distribution, (2) occupies exceptionally diverse habitats and (3) exhibits subtle regional differences in morphology. Phylogenetic trees reconstructed using nuclear and mitochondrial genes recovered three well-supported clades corresponding with geography. Morphological results based on canonical variates analysis show that these clades exhibit subtle differences in head casque morphology. Ecological niche modelling results found that these phylogenetic groups also occupy unique environmental space and exhibit patterns of regional endemism typical of other endemic reptiles. Combined, our findings provide diverse yet consistent evidence for the existence of three species. Consequently, we elevate the subspecies F. lateralis major to species rank and name a new species distributed in northern and western Madagascar. Initial ecological divergence, associated with speciation of F. lateralis in humid eastern habitat, fits the Ecographic Constraint model for species diversification in Madagascar. By contrast, the second speciation event provides some support for the Riverine Barrier model, with the Mangoky River possibly causing initial isolation between species. These findings thus support two contrasting models of speciation within closely related species and demonstrate the utility of applying a combined-evidence approach for detecting cryptic speciation.

  9. The amino acid and stable isotope biogeochemistry of elephant bird ( Aepyornis) eggshells from southern Madagascar

    NASA Astrophysics Data System (ADS)

    Clarke, Simon J.; Miller, Gifford H.; Fogel, Marilyn L.; Chivas, Allan R.; Murray-Wallace, Colin V.

    2006-09-01

    A diverse suite of animals became extinct on Madagascar during the Late Holocene. As observed on landmasses elsewhere, the extinction process broadly coincided with the arrival of people. Our research on the amino acid racemisation and the carbon and oxygen isotope biogeochemistry of elephant bird ( Aepyornis) eggshells from southern Madagascar refines models that attempt to explain the extinction process. A correlation between the extent of isoleucine epimerisation (aIle/Ile) and radiocarbon age of eggshells allows aIle/Ile to serve as a proxy for eggshell age. The aIle/Ile values indicate the majority (87%) of eggshells in this study are Holocene, with the remainder representing Pleistocene Aepyornis populations, and that further amino acid analyses would help to constrain the timing of Aepyornis extinction. Carbon isotope ratios in the organic and calcite fractions of eggshells indicate that Aepyornis primarily browsed C 3 vegetation. Oxygen isotope values are more negative and less variable than in eggshells of ostriches living in semi-arid environments, suggesting that Aepyornis populations relied upon groundwater-fed coastal wetlands for their drinking water. The isotope results require that the changing abundances of C 3 vegetation and groundwater-fed watering points be considered in models that aim to understand the extinction of Aepyornis in southern Madagascar.

  10. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

    PubMed

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-02-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

  11. Searching for the oldest baobab of Madagascar: radiocarbon investigation of large Adansonia rubrostipa trees.

    PubMed

    Patrut, Adrian; von Reden, Karl F; Danthu, Pascal; Pock-Tsy, Jean-Michel Leong; Patrut, Roxana T; Lowy, Daniel A

    2015-01-01

    We extended our research on the architecture, growth and age of trees belonging to the genus Adansonia, by starting to investigate large individuals of the most widespread Malagasy species. Our research also intends to identify the oldest baobabs of Madagascar. Here we present results of the radiocarbon investigation of the two most representative Adansonia rubrostipa (fony baobab) specimens, which are located in south-western Madagascar, in the Tsimanampetsotse National Park. We found that the fony baobab called "Grandmother" consists of 3 perfectly fused stems of different ages. The radiocarbon date of the oldest sample was found to be 1136 ± 16 BP. We estimated that the oldest part of this tree, which is mainly hollow, has an age close to 1,600 yr. This value is comparable to the age of the oldest Adansonia digitata (African baobab) specimens. By its age, the Grandmother is a major candidate for the oldest baobab of Madagascar. The second investigated specimen, called the "polygamous baobab", consists of 6 partially fused stems of different ages. According to dating results, this fony baobab is 1,000 yr old. This research is the first investigation of the structure and age of Malagasy baobabs.

  12. Biodiversity conservation and drug discovery: Can they be combined? The Suriname and Madagascar experiences

    PubMed Central

    Cao, Shugeng; Kingston, David G. I.

    2009-01-01

    The approach to new drugs through natural products has proved to be the single most successful strategy for the discovery of new drugs, but in recent years its use has been deemphasized by many pharmaceutical companies in favor of approaches based on combinatorial chemistry and genomics, among others. Drug discovery from natural sources requires continued access to plant, marine, and microbial biomass, and so the preservation of tropical rainforests is an important part of our drug discovery program. Sadly, many of the tropical forests of the world are under severe environmental pressure, and deforestation is a serious problem in most tropical countries. One way to combat this loss is to demonstrate their value as potential sources of new pharmaceutical or agrochemical products. As part of an effort to integrate biodiversity conservation and drug discovery with economic development, we initiated an International Cooperative biodiversity Group (ICBG) to discover potential pharmaceuticals from the plant biodiversity of Suriname and Madagascar. The Group, established with funding from agencies of the United States government, involved participants from the USA, Suriname, and Madagascar. The basic approach was to search for bioactive plants in the Suriname and Malagasy flora, and to isolate their bioactive constituents by the best available methods, but the work included capacity building as well as research. Progress on this project will be reported, drawing on results obtained from the isolation of bioactive natural products from Suriname and Madagascar. The benefits of this general approach to biodiversity and drug discovery will also be discussed. PMID:20161050

  13. Preliminary findings on identification of mycorrhizal fungi from diverse orchids in the Central Highlands of Madagascar.

    PubMed

    Yokoya, Kazutomo; Zettler, Lawrence W; Kendon, Jonathan P; Bidartondo, Martin I; Stice, Andrew L; Skarha, Shannon; Corey, Laura L; Knight, Audrey C; Sarasan, Viswambharan

    2015-11-01

    The Orchid flora of Madagascar is one of the most diverse with nearly 1000 orchid taxa, of which about 90% are endemic to this biodiversity hotspot. The Itremo Massif in the Central Highlands of Madagascar with a Highland Subtropical climate range encompasses montane grassland, igneous and metamorphic rock outcrops, and gallery and tapia forests. Our study focused on identifying culturable mycorrhizae from epiphytic, lithophytic, and terrestrial orchid taxa to understand their diversity and density in a spatial matrix that is within the protected areas. We have collected both juvenile and mature roots from 41 orchid taxa for isolating their orchid mycorrhizal fungi (OMF), and to culture, identify, and store in liquid nitrogen for future studies. Twelve operational taxonomic units (OTUs), of three known orchid mycorrhizal genera, were recognized by analysis of internal transcribed spacer (ITS) sequences of 85 isolates, and, by comparing with GenBank database entries, each OTU was shown to have closely related fungi that were also found as orchid associates. Orchid and fungal diversity were greater in gallery forests and open grasslands, which is very significant for future studies and orchid conservation. As far as we know, this is the first ever report of detailed identification of mycorrhizal fungi from Madagascar. This study will help start to develop a programme for identifying fungal symbionts from this unique biodiversity hotspot, which is undergoing rapid ecosystem damage and species loss. The diversity of culturable fungal associates, their density, and distribution within the Itremo orchid hotspot areas will be discussed.

  14. On the presence of plutonium in Madagascar following the SNAP-9A satellite failure.

    PubMed

    Rääf, C; Holm, E; Rabesiranana, N; Garcia-Tenorio, R; Chamizo, E

    2017-10-01

    This study examined the (238)Pu and (239+240)Pu activity concentration and the (240)Pu/(239)Pu atomic ratio in peat bogs sampled in 2012 from marshlands in central Madagascar. The purpose was to investigate the presence of plutonium isotopes, (238, 239, 240)Pu, from the 1964 satellite failure carrying a SNAP-9A radiothermal generator. With an average (238)Pu/(239+240)Pu activity ratio of 0.165 ± 0.02 (decay corrected to 1964), the peat bogs in Madagascar exhibit similar values as the ones found in the southeastern African continent, except they are one order of magnitude higher than expected (0.025) from global fallout in the Southern Hemisphere. The (240)Pu/(239)Pu atomic ratio showed a distinct decrease for layers dating back to the mid-1960s (down to 0.069 compared with an anticipated ratio of 0.17 for global fallout), indicating that the SNAP-9A failure also resulted in an elevated deposition of (239)Pu. The obtained results demonstrate that further Pu analysis in Madagascar and in southeastern continental Africa is necessary to fully account for the regional Pu deposition from the SNAP-9A event. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Natural selection for the Duffy-null allele in the recently admixed people of Madagascar.

    PubMed

    Hodgson, Jason A; Pickrell, Joseph K; Pearson, Laurel N; Quillen, Ellen E; Prista, António; Rocha, Jorge; Soodyall, Himla; Shriver, Mark D; Perry, George H

    2014-08-22

    While gene flow between distantly related populations is increasingly recognized as a potentially important source of adaptive genetic variation for humans, fully characterized examples are rare. In addition, the role that natural selection for resistance to vivax malaria may have played in the extreme distribution of the protective Duffy-null allele, which is nearly completely fixed in mainland sub-Saharan Africa and absent elsewhere, is controversial. We address both these issues by investigating the evolution of the Duffy-null allele in the Malagasy, a recently admixed population with major ancestry components from both East Asia and mainland sub-Saharan Africa. We used genome-wide genetic data and extensive computer simulations to show that the high frequency of the Duffy-null allele in Madagascar can only be explained in the absence of positive natural selection under extreme demographic scenarios involving high genetic drift. However, the observed genomic single nucleotide polymorphism diversity in the Malagasy is incompatible with such extreme demographic scenarios, indicating that positive selection for the Duffy-null allele best explains the high frequency of the allele in Madagascar. We estimate the selection coefficient to be 0.066. Because vivax malaria is endemic to Madagascar, this result supports the hypothesis that malaria resistance drove fixation of the Duffy-null allele in mainland sub-Saharan Africa. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  16. Conservation education in Madagascar: three case studies in the biologically diverse island-continent.

    PubMed

    Dolins, Francine L; Jolly, Alison; Rasamimanana, Hantanirina; Ratsimbazafy, Jonah; Feistner, Anna T C; Ravoavy, Florent

    2010-05-01

    Few Malagasy children and adults are aware of the rare and unique fauna and flora indigenous to their island-continent, including flagship lemur species. Even the Malagasy ancestral proverbs never mentioned lemurs, but these same proverbs talked about the now extinct hippopotamus. Madagascar's geography, history, and economic constraints contribute to severe biodiversity loss. Deforestation on Madagascar is reported to be over 100,000 ha/year, with only 10-15% of the island retaining natural forest [Green & Sussman, 1990]. Educating children, teacher-training, and community projects about environmental and conservation efforts to protect the remaining natural habitats of endangered lemur species provide a basis for long-term changes in attitudes and practices. Case studies of three conservation education projects located in different geographical regions of Madagascar, Centre ValBio, Madagacar Wildlife Conservation Alaotra Comic Book Project, and The Ako Book Project, are presented together with their ongoing stages of development, assessment, and outcomes. We argue that while nongovernmental organizational efforts are and will be very important, the Ministry of Education urgently needs to incorporate biodiversity education in the curriculum at all levels, from primary school to university.

  17. A giant frog with South American affinities from the Late Cretaceous of Madagascar

    PubMed Central

    Evans, Susan E.; Jones, Marc E. H.; Krause, David W.

    2008-01-01

    Madagascar has a diverse but mainly endemic frog fauna, the biogeographic history of which has generated intense debate, fueled by recent molecular phylogenetic analyses and the near absence of a fossil record. Here, we describe a recently discovered Late Cretaceous anuran that differs strikingly in size and morphology from extant Malagasy taxa and is unrelated either to them or to the predicted occupants of the Madagascar–Seychelles–India landmass when it separated from Africa 160 million years ago (Mya). Instead, the previously undescribed anuran is attributed to the Ceratophryinae, a clade previously considered endemic to South America. The discovery offers a rare glimpse of the anuran assemblage that occupied Madagascar before the Tertiary radiation of mantellids and microhylids that now dominate the anuran fauna. In addition, the presence of a ceratophryine provides support for a controversial paleobiogeographical model that posits physical and biotic links among Madagascar, the Indian subcontinent, and South America that persisted well into the Late Cretaceous. It also suggests that the initial radiation of hyloid anurans began earlier than proposed by some recent estimates. PMID:18287076

  18. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides

    PubMed Central

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-01-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar. PMID:26844772

  19. Temporal and spatial evolution of dynamic support from river profiles: A framework for Madagascar

    NASA Astrophysics Data System (ADS)

    Roberts, Gareth G.; Paul, Jonathan D.; White, Nicky; Winterbourne, Jeffrey

    2012-04-01

    We present a strategy for calculating uplift rates as a function of space and time from large sets of longitudinal river profiles. This strategy assumes that the shape of a river profile is controlled by the history of uplift rate and moderated by the erosional process. We assume that upstream drainage area is invariant. The algorithm was tested on a set of ˜100 river profiles which were extracted from a digital elevation model of Madagascar. This set of profiles was simultaneously inverted to obtain uplift rate as a smooth function of space and time. The fit between observed and calculated profiles is excellent and suggests that Madagascar was uplifted by 1-2 km at rates of 0.2-0.4 mm/yr during the last ˜15 Myrs. The location of Madagascar suggests that its topographic elevation is maintained by convective circulation of the sub-lithospheric mantle. Residual depth anomalies of oceanic fragments encompassing the island show that the island straddles a dynamic topographic gradient which generates asymmetric Neogene uplift. Volcanism, warped peneplains and uplifted marine terraces corroborate the existence of youthful uplift. We suggest that sets of longitudinal river profiles contain useful information about the history of regional uplift which can be extracted by inverse modeling and calibrated by independent geologic observations.

  20. Implementing reproducible research using the Madagascar open-source software package

    NASA Astrophysics Data System (ADS)

    Fomel, S.

    2015-12-01

    Reproducible research is a concept pioneered by Jon Claerbout. It refers to the discipline of attaching software code and data to scientific publications, which enables the reader to reproduce, verify, and extend published computational experiments. The Madagascar open-source software package provides an example of implementing the reproducible research discipline in geophysical publications. The package contains not only software tools for making geophysical computations but also research papers complete with links to data and reproducible data-analysis workflows. When researchers discover a research paper published on the Madagascar website and install Madagascar, they are able to follow the links and replicate all computations to verify the published computational results. Of course, reproducibility is not the goal in itself. The goal is to be able to extend previously published research by, for example, trying new computations on previously used data or previously used computations on new data. The Madagscar collection currently contains about 150 research papers and book chapters and about 900 reproducible scripts. More than 80 people from different organizations around the world have contributed to the development. This experience shows that, instead of being the responsibility of an individual author, computational reproducibility can become the responsibility of open-source scientific-software communities. Our experience shows how a dedicated community effort can keep a body of computational research alive by actively maintaining its reproducibility.

  1. Biogeography of the Malagasy Celastraceae: Multiple independent origins followed by widespread dispersal of genera from Madagascar.

    PubMed

    Bacon, Christine D; Simmons, Mark P; Archer, Robert H; Zhao, Liang-Cheng; Andriantiana, Jacky

    2016-01-01

    Of the 97 currently recognized genera of Celastraceae, 19 are native to Madagascar, including six endemics. In this study we conducted the most thorough phylogenetic analysis of Celastraceae yet completed with respect to both character and taxon sampling, and include representatives of five new endemic genera. Fifty-one new accessions, together with 328 previously used accessions of Celastrales, were sampled for morphological characters, two rDNA gene regions, and two plastid gene regions. The endemic Malagasy genera are resolved in two separate lineages-Xenodrys by itself and all other endemic genera in a clade that also includes four lineages inferred to have dispersed from Madagascar: Brexia madagascariensis (Mascarene Islands, coastal Africa), Elaeodendron (West Indies, Africa to New Caledonia), and Pleurostylia (Africa to New Caledonia). Of the 12 extant Malagasy Celastraceae lineages identified, eight are clearly of African origin. The origins of the remaining four lineages are less clear, but reasonable possibilities include America, Eurasia, Africa, southern India, Malesia, and Australia. Based on 95% credible age intervals from fossil-calibrated molecular dating, all 12 extant Malagasy Celastraceae lineages appear to have arisen following dispersal after the separation of Madagascar from other landmasses within the last 70 million years.

  2. Madagascar's Escape from Africa: New Constraints and Understanding for Plate Tectonic Reconstructions

    NASA Astrophysics Data System (ADS)

    Phethean, J. J. J.; Davies, R. J.; Van Hunen, J.; Kalnins, L. M.; McCaffrey, K. J. W.

    2015-12-01

    We present a new plate tectonic reconstruction for the drift of Madagascar away from East Africa using the new Sandwell and Smith gravity dataset (V23.1). Detailed interpretation of free-air and Bouguer anomalies, together with gravity gradients, has allowed interpretation of the extinct mid ocean ridge and associated fracture zone lineaments from the Western Somali Basin. Combined with temporal constraints from previous ocean magnetic anomaly interpretations, this analysis produces a reconstruction that supports Reeves' (2014) tight fit of Gondwana fragments. Furthermore, it sheds light on the nature of the Davie Fracture Zone (DFZ) and the position of the continent-ocean boundary (COB) in the region. The model predicts that the COB lies along the Rovuma Basin; and that offshore Tanzania is most likely a segmented and obliquely rifted margin, not a transform continental margin along the DFZ as previously thought. This places the COB up to several hundred kilometres farther inboard than previous interpretations, which is supported by new seismic evidence of oceanic crust inboard of the DFZ. We show the DFZ to be a major ocean-ocean fracture zone formed by the coalescence of several smaller fracture zones during a change in plate motions as Madagascar escaped from Africa. This new geodynamical understanding has important implications for petroleum industry activities in East Africa, as the expected heat flow varies dramatically between oceanic and continental crust. Reeves, C., 2014. The position of Madagascar within Gondwana and its movements during Gondwana dispersal. J. Afr. Earth. Sci. 94, 45-57.

  3. Plants traditionally prescribed to treat tazo (malaria) in the eastern region of Madagascar

    PubMed Central

    Randrianarivelojosia, Milijaona; Rasidimanana, Valérie T; Rabarison, Harison; Cheplogoi, Peter K; Ratsimbason, Michel; Mulholland, Dulcie A; Mauclère, Philippe

    2003-01-01

    Background Malaria is known as tazo or tazomoka in local terminology in Madagascar. Within the context of traditional practice, malaria (and/or malaria symptoms) is commonly treated by decoctions or infusions from bitter plants. One possible approach to the identification of new antimalarial drug candidates is to search for compounds that cure or prevent malaria in plants empirically used to treat malaria. Thus, it is worth documenting the ethnobotanical data, and testing the antiplasmodial activity of the extractive from plants. Methods We interviewed traditional healers, known locally as ombiasy, at Andasibe in the eastern, rainy part of Madagascar. We recorded details of the preparation and use of plants for medicinal purposes. We extracted five alkaloids from Z. tsihanimposa stem bark, and tested them in vitro against Plasmodium falciparum FCM29. Results We found that traditional healers treat malaria with herbal remedies consisting of one to eight different plants. We identified and listed the medicinal plants commonly used to treat malaria. The plants used included a large number of species from different families. Zanthoxylum sp (Rutaceae) was frequently cited, and plants from this genus are also used to treat malaria in other parts of Madagascar. From the plant list, Zanthoxylum tsihanimposa, bitter plant endemic to Madagascar, was selected and examined. Five alkaloids were isolates from the stem bark of this plant, and tested in vitro against malaria parasite. The geometric mean IC50 values ranged from 98.4 to 332.1 micromolar. The quinoline alkaloid gamma-fagarine exhibited the strongest antiplasmodial activity. Conclusions The current use of plants for medicinal purposes reflects the attachment of the Malagasy people to their culture, and also a lack of access to modern medicine. The possible extrapolation of these in vitro findings, obtained with plant extracts, to the treatment of malaria and/or the signs evoking malaria is still unclear. If plants are

  4. Oceanic variability around Madagascar : connections to the large-scale Indian Ocean circulation and its forcing

    NASA Astrophysics Data System (ADS)

    Palastanga, V.

    2007-06-01

    The connection between the mesoscale eddy activity around Madagascar and the large-scale interannual variability in the Indian Ocean is investigated. We use the combined TOPEX/Poseidon-ERS sea surface height (SSH) data for the period 1993-2003. The SSH-fields in the Mozambique Channel and east of Madagascar exhibit a significant interannual oscillation. This is related to the arrival of large-scale anomalies that propagate westward in the band 10-15S in response to the Indian Ocean dipole (IOD) events. Positive (negative) SSH anomalies associated to a positive (negative) IOD phase induce a shift in the intensity and position of the tropical and subtropical gyres in the Indian Ocean. A weakening (strengthening) results in the intensity of the South Equatorial Current and its branches along east Madagascar. In addition, the flow through the narrows of the Mozambique Channel around 17S increases (decreases) during periods of a stronger and northward (southward) extension of the subtropical (tropical) gyre. Interaction between the currents in the narrows and southward propagating eddies from the northern Channel leads to interannual variability in the eddy kinetic energy of the central Channel in phase with the one in the SSH-field. The origin of the eddy variability along the 25S band in the Indian Ocean is also investigated. We have found that the surface circulation east of Madagascar shows an anticyclonic subgyre bounded to the south by eastward flow from southwest Madagascar and to the north by the westward flowing South Equatorial Current (SEC) between 15-20S. The shallow, eastward flow, named the South Indian Ocean Countercurrent (SICC), extends above the deep reaching, westward flowing SEC up to 95E, with its core over the latitude of the high variability band. Applying a 2-layer model reveals that regions of large vertical shear along the SICC-SEC system are baroclinically unstable. Estimates of the frequencies (3.5-6 times/year) and wavelengths (290-470 km

  5. Seismic anisotropy of the lithosphere/asthenosphere system beneath southern Madagascar

    NASA Astrophysics Data System (ADS)

    Reiss, M. C.; Rumpker, G.; Tilmann, F. J.; Yuan, X.; Rindraharisaona, E. J.

    2015-12-01

    Madagascar is considered as a key region with respect to the assembly and break-up of the supercontinent Gondwana. Following the collision between East- and West-Gondwana (~700-650 Ma), its position was central to the Pan-African orogeny and later to the break-up between East-Africa, India and Antarctica. Today, Madagascar consists of different tectonic units; the eastern two thirds of the island are composed mainly of Precambian rocks, whereas the western part is dominated by sedimentary deposits. Southern Madagascar is characterized by several NS to NW-SE trending shear zones. To increase our understanding of these structures and related tectonic processes, we installed a dense temporary seismic network in southern Madagascar. It consisted of 50 stations, which were in operation for up to 2 years between 2012 and 2014. We present results from shear-wave splitting analyses to infer the seismic anisotropy of the lithosphere-asthenosphere system in response to deformational processes. The polarization of the fast shear wave and the delay time between the fast and slow waves provide constraints on the anisotropic fabric. For our study, we use core phases from up to 22 events. We first apply a conventional single-event splitting analysis by minimizing the transverse component. For stations that do not show a significant azimuthal dependence of the splitting parameters, we also apply a joint inversion involving all recorded waveforms from several events. Our results exhibit delay times between 0.4 and 1.5 s. In the center of the E-W profile, fast axes are mainly oriented NNW-SSE, whereas east of the Ranotsara zone, fast axes are oriented NE-SW. We apply full-waveform FD modeling to examine the effects of various anisotropic models of the crust and mantle. Our results indicate that recently proposed mantle flow models are insufficient to explain the small scale variations of splitting parameters observed along our profile. Our observations are best characterized by

  6. On the nature of the Madagascar dipoles: An analysis from Argo profiling floats and altimetry measurements

    NASA Astrophysics Data System (ADS)

    Aguiar-González, Borja; Ponsoni, Leandro; Ridderinkhof, Herman; de Ruijter, Will P. M.; Maas, Leo R. M.

    2016-04-01

    The South East Madagascar Current (SEMC) flows poleward along the eastern coast of Madagascar as a western boundary current which further south provides some of the source waters of the Agulhas Current, either directly or in the form of eddies. We investigate the region of dipole formation south of Madagascar combining vertical T/S profiles from Argo floats, altimetry measurements and an existing eddy detection algorithm. Results from our analysis show that the dipole consists of an anticyclonic intrathermocline eddy (ITE) formed on its southern flank and a cyclonic ITE formed on its northern flank. Both lobes of the dipole exhibit similar T/S properties throughout the water column, although vertically shifted within the thermocline depending on its nature: upward in a cyclonic ITE and downward in an anticyclonic ITE. A subsurface salinity maximum of about 35.5 psu characterizes the upper layers with Subtropical Surface Water (STSW). At intermediate levels, a well defined path of South Indian Central Water (SICW) extends throughout the water column up to reach a minimum in salinity of 34.5 psu, corresponding to Antarctic Intermediate Water (AAIW). Below, at deep layers, the North Atlantic Deep Water (NADW) is found. The intrathermocline nature of the Madagascar dipoles has not been previously reported and represents an important feature to be considered when assessing the heat and salt fluxes driven by eddy movement and contributing to the Agulhas Current. Unlike surface eddies, intrathermocline eddies strongly influence the intermediate/deeper layers in the oceans and, hence, may have a larger contribution in the spreading rates and pathways of water masses. Because the intrathermocline nature of eddies is invisible to altimetry measurements, these results stress the importance of combining altimetry with historical records of Argo profiles which uncover eddy dynamics below the sea surface. Lastly, we further investigate from altimetry the area of dipole formation

  7. Geochemical Signatures of Neoproterozoic Granites and Granitoid-gneisses from Angavo Belt, Central Madagascar

    NASA Astrophysics Data System (ADS)

    Raharimahefa, T.

    2015-12-01

    The basement rocks of Madagascar record high-grade metamorphism, magmatism, and contractional and extensional structures that accompanied the collision of the eastern and western Gondwana segments of the supercontinent followed by its collapse. In the eastern central Madagascar, granitoids dominate the landscape and occur in a large area near and within the N-S trending highly strained zone known as the Angavo Shear Zone or Angavo belt. The area is a key in understanding the evolution of basement of Madagascar and the reconstruction of the Gondwana supercontinent. These granitoids range from layered to massive and previously published U-Pb zircon dating yielded three distinctive Neoproterozoic magmatisms at 770 Ma to 820 Ma, ca. 660Ma, and ca 550Ma. However, it was unknown whether these ages represent distinct magmatic pulses or reflect a continuous granitoid emplacement. This work contributes to the knowledge of the Malagasy basement rocks and to explore and discuss the origin and petrotectonic evolution of the granites and granitoid-gneisses from this part of the Madagascar. The rock samples are placed into three groups: group A and B for granitoid-gneisses and a third group for the granite layers. Group A and B are metaluminous and slightly peraluminous, respectively. All rocks have typical subduction zone calc-alkaline signatures. Group A is characterized by enrichment in large ion lithophile elements (LILE) but low U, LREE enrichment, depletion in the high field strength elements (HFSE). In contrast, Group B has REE patterns closely similar to Archean sediments. The granite layers show fractionated REE patterns in which HREE patterns show strong correlation with Zr abundances. Trends in major element variation diagrams and the enrichment of incompatible elements could be explained by simple fractional crystallization, while the overall geochemical signatures reflect either (1) melting of ancient crust or (2) crustal contamination of a more evolved magmas that

  8. Deep phylogenetic divergence between Scolytoplatypus and Remansus, a new genus of Scolytoplatypodini from Madagascar (Coleoptera, Curculionidae, Scolytinae)

    PubMed Central

    Jordal, Bjarte H.

    2013-01-01

    Abstract Scolytoplatypodini Blandford is a monotypic tribe of ambrosia beetles found in Asia, Madagascar and Africa. Only three species are currently known from Madagascar and four additional species are here described as new to science. Phylogenetic analyses of morphological and molecular data revealed that four of the seven endemic species are deeply separated from all other species by genetic and distinct morphological characters and therefore placed in a new genus Remansus Jordal. The split between this ancient lineage and Scolytoplatypus Schaufuss was estimated to approximate Palaeocene age (63 Ma), extending the minimum age of ambrosia feeding for this tribe to the beginning of the Palaeocene‒Eocene thermal maximum (PETM). In addition to the ancient origin of Remansus in Madagascar during the Palaeocene, a second origin occurred in Scolytoplatypus no more than 13 Ma. A geographical origin of the latter in South-Eastern Africa was unequivocally inferred from the phylogenies. PMID:24294090

  9. The Permian-Triassic boundary in the southern Morondava basin of Madagascar as defined by plant microfossils

    NASA Astrophysics Data System (ADS)

    Wright, R. P.; Askin, R. A.

    Surface and subsurface rock samples contain plant microfossils which locate the Permian-Triassic boundary within the Sakamena Group of southern Madagascar. Upper Permian rocks in Madagascar are unique because unusually high proportions of Guttulapollenites and Weylandites pollen are found together with occasional specimens of Lunatisporites pellucidus, a species elsewhere considered diagnostic of the Triassic. The lower most Triassic strata in Madagascar, however, contain a more characteristic Gondwana assemblage including trilete cavate spores (Densoisporites, Lundbladispora and Kraeuselisporites spp.), other diagnostic spores, and taeniate bisaccate pollen (Lunatisporites spp.). Organic-walled microphytoplankton from some horizons in the lower half of the Middle Sakamena Group record the extensive marine transgression recognized worldwide for the earliest Triassic. We believe that the Lower Middle Sakamena succession corresponds to that of the upper Chhidru to Kathwai-Mittiwali sequence of the Salt Range, Pakistan, with the Permian-Triassic boundary approximating the Lower-Middle Sakamena transition.

  10. Rapid human-induced landscape transformation in Madagascar at the end of the first millennium of the Common Era

    NASA Astrophysics Data System (ADS)

    Burns, Stephen J.; Godfrey, Laurie R.; Faina, Peterson; McGee, David; Hardt, Ben; Ranivoharimanana, Lovasoa; Randrianasy, Jeannot

    2016-02-01

    The environmental impact of the early human inhabitants of Madagascar remains heavily debated. We present results from a study using two stalagmites collected from Anjohibe Cave in northwestern Madagascar to investigate the paleoecology and paleoclimate of northwestern Madagascar over the past 1800 years. Carbon stable isotopic data indicate a rapid, complete transformation from a flora dominated by C3 plants to a C4 grassland system. This transformation is well replicated in both stalagmites, occurred at 890 CE and was completed within one century. We infer that the change was the result of a dramatic increase in the use of fire to promote the growth of grass for cattle fodder. Further, stalagmite oxygen isotope ratios show no significant variation across the carbon isotope excursion, demonstrating that the landscape transformation was not related to changes in precipitation. Our study illustrates the profound impact early inhabitants had on the environment, and implies that forest loss was one trigger of megafaunal extinction.

  11. To Madagascar and back: long-distance, return migration across open ocean by a pregnant female bull shark Carcharhinus leucas.

    PubMed

    Lea, J S E; Humphries, N E; Clarke, C R; Sims, D W

    2015-12-01

    A large, pregnant, female bull shark Carcharhinus leucas was tracked migrating from Seychelles across open ocean to south-east Madagascar, c. 2000 km away, and back again. In Madagascar, the shark spent a prolonged period shallower than 5 m, consistent with entering estuarine habitat to pup, and upon return to Seychelles the shark was slender and no longer gravid. This represents an unprecedented return migration across the open ocean for a C. leucas and highlights the need for international collaboration to manage the regional C. leucas population sustainably.

  12. Seismo and sequence stratigraphy of Cenozoic units of the Morondava Basin, offshore western Madagascar

    NASA Astrophysics Data System (ADS)

    Kaufmann, Dirk; Stollhofen, Harald; Klimke, Jennifer; Franke, Dieter

    2015-04-01

    The N-S trending Morondava Basin extends in width from western onshore Madagascar over about 350 km westwards to the offshore Davie Ridge in the Mozambique Channel. Although basin formation was initiated during Karoo times, the main basin evolution took place during Jurassic rifting and subsequent drifting until middle Cretaceous as a result of Gondwana breakup (Geiger et al., 2004). Contemporaneous to the separation of India and Madagascar widespread flood basalts were emplaced during the late Cretaceous (Storey et al., 1995). Present knowledge of the Morondava Basin is mainly based on outcrop studies, seismic surveys and borehole information (e.g. Geiger et al., 2004), gathered in western onshore Madagascar, although the fast majority of the basin, including its depocenter is located offshore in the Mozambique Channel, now at up to 3,500 m water depth. Almost all of the recent offshore studies of the Morondava Basin rely on industrial data but up to date publications of exploration results are generally rare and mostly anonymized. Our study aims to extend knowledge, particularly on the offshore seismic and sequence stratigraphy of the Morondava Basin. A key question is also to test the proposed tectonic stability of the Davie Ridge over the last 40 Ma. For this purpose 12 seismic profiles and bathymetric data, acquired in early 2014 by RV SONNE, are interpreted. Most of the profiles cover the distal deep marine areas of the northern Morondava Basin between the Davie Ridge and the shelf break of Madagascar. Top Cretaceous, Top Eocene, Top Oligocene, the Middle Miocene Unconformity and the Base Pliocene, are mapped as major seismic marker horizons. Especially shelf and slope sedimentary units are important resources to reconstruct the tectonostratigraphic basin evolution. At the continental slope diffuse to chaotic seismic pattern of Miocene and younger age are identified which are subdivided by laterally continuous, high frequency reflectors with a higher

  13. Structural mapping and analysis of a Madagascar Precambrian shear zone using enhanced Landsat Thematic Mapper Data

    SciTech Connect

    Kilmer, D.S.; Duncan, I.J. )

    1990-05-01

    Recently, the west coast of Madagascar has become a frontier region for petroleum exploration. Major structures in the Precambrian shield of Madagascar may have a strong control on the development of sedimentary basins, as has been documented in the Morondava basin. The 2.5-3.0+ Ga shield of Madagascar is an amphibolite- to granulite-grade metamorphic gneiss terrain, intruded by anorthosites and 550-Ma granites and pegmatites. Landsat Thematic Mapper data provides a cost-effective method for regional-scale structural mapping of this poorly known terrain. A five-component linear mixing model has been used to enhance the lithologic information in this six-band data. Lithologic component images thus produced utilize the full geologic spectral range of the data. A preliminary structural geologic map compiled from the component images has greater detail than existing maps at 1:100,000 scale, to which it has been compared. The Ankafotra-Saririaky shear zone has been identified as a north-northeast-trending, 15- to 20-km-wide region of appressed folds, attenuated layering, and subparallel faults on the western side of the shield. Two anorthosite massifs that occur within this shear zone have the structural characteristics of boudins in a ductile matrix. The shear deformed a preexisting terrain of poly-phase folding, characterized by tight folds and complex fold interference structures displayed by basins and domes on a scale of 10 km. Enhanced remote sensing data can be used to characterize the nature and mechanism of shear deformation in such zones.

  14. Diagnosis of Bubonic Plague by PCR in Madagascar under Field Conditions

    PubMed Central

    Rahalison, L.; Vololonirina, E.; Ratsitorahina, M.; Chanteau, S.

    2000-01-01

    The diagnostic value of a PCR assay that amplifies a 501-bp fragment of the Yersinia pestis caf1 gene has been determined in a reference laboratory with 218 bubo aspirates collected from patients with clinically suspected plague managed in a regional hospital in Madagascar. The culture of Y. pestis and the detection of the F1 antigen (Ag) by enzyme-linked immunosorbent assay (ELISA) were used as reference diagnostic methods. The sensitivity of PCR was 89% (57 of 64) for the Y. pestis-positive patients, and 80.7% (63 of 78) for the F1 Ag-positive patients. The specificity of PCR for the culture-, F1 Ag-, and antibody-negative patients (n = 105) was 100%. Because in Madagascar most patients with plague are managed and their clinical samples are collected in remote villages, the usefulness of PCR was evaluated for routine diagnostic use in the operational conditions of the control program. The sensitivity of PCR was 50% (25 of 50) relative to the results of culture and 35.2% (19 of 54) relative to the results of the F1 Ag immunocapture ELISA. The specificity of PCR under these conditions was 96%. In conclusion, the PCR method was found to be very specific but not as sensitive as culture or the F1 Ag detection method. The limitation in sensitivity may have been due to suboptimal field conditions and the small volumes of samples used for DNA extraction. This technique is not recommended as a routine diagnostic test for plague in Madagascar. PMID:10618097

  15. Medicinal plants used by women from Agnalazaha littoral forest (Southeastern Madagascar)

    PubMed Central

    2013-01-01

    Background The country of Madagascar is renowned for its high level of biodiversity and endemism, as well as the overwhelming pressures and threats placed on the natural resources by a growing population and climate change. Traditional medicine plays an important role in the daily lives of the Malagasy for various reasons including limited access to healthcare, limited markets and traditional values. The objective of this study was to assess the modern utitilization of the Agnalazaha Forest by the local population in Mahabo-Mananivo, Madagascar, for medicinal plants used by women, and to establish a list of medicinal plants used by women sourced from Agnalazaha Forest. Methods Ethnobotanical studies were conducted over a period of five months in 2010 to determine the diversity of medicinal plants used by women in the commune of Mahabo-Mananivo. In all, 498 people were interviewed, both male and female ranging age from 15 to over 60 years old. Results 152 medicinal plants used by local people were collected during the ethnobotanical studies. Among the recorded species, eight native species are widely used by women. These species are known for their therapeutic properties in treating placental apposition and complications during childbirth as well as tropical illnesses such as malaria, filariasis, and sexual diseases like gonorrhea and syphilis. Conclusions Littoral forests are rare ecosystems that are highly threatened on the island nation of Madagascar. Our investigation into the use of medicinal plants sourced from and around the Agnalazaha Forest by the women of Mahabo-Mananivo reinforces the need for this natural resource as a first line of health care for rural families. PMID:24188563

  16. Genetic evidence that the Makira region in northeastern Madagascar is a hotspot of malaria transmission.

    PubMed

    Rice, Benjamin L; Golden, Christopher D; Anjaranirina, Evelin Jean Gasta; Botelho, Carolina Mastella; Volkman, Sarah K; Hartl, Daniel L

    2016-12-20

    Encouraging advances in the control of Plasmodium falciparum malaria have been observed across much of Africa in the past decade. However, regions of high relative prevalence and transmission that remain unaddressed or unrecognized provide a threat to this progress. Difficulties in identifying such localized hotspots include inadequate surveillance, especially in remote regions, and the cost and labor needed to produce direct estimates of transmission. Genetic data can provide a much-needed alternative to such empirical estimates, as the pattern of genetic variation within malaria parasite populations is indicative of the level of local transmission. Here, genetic data were used to provide the first empirical estimates of P. falciparum malaria prevalence and transmission dynamics for the rural, remote Makira region of northeastern Madagascar. Longitudinal surveys of a cohort of 698 total individuals (both sexes, 0-74 years of age) were performed in two communities bordering the Makira Natural Park protected area. Rapid diagnostic tests, with confirmation by molecular methods, were used to estimate P. falciparum prevalence at three seasonal time points separated by 4-month intervals. Genomic loci in a panel of polymorphic, putatively neutral markers were genotyped for 94 P. falciparum infections and used to characterize genetic parameters known to correlate with transmission levels. Overall, 27.8% of individuals tested positive for P. falciparum over the 10-month course of the study, a rate approximately sevenfold higher than the countrywide average for Madagascar. Among those P. falciparum infections, a high level of genotypic diversity and a high frequency of polygenomic infections (68.1%) were observed, providing a pattern consistent with high and stable transmission. Prevalence and genetic diversity data indicate that the Makira region is a hotspot of P. falciparum transmission in Madagascar. This suggests that the area should be highlighted for future

  17. Geogenetic patterns in mouse lemurs (genus Microcebus) reveal the ghosts of Madagascar's forests past

    PubMed Central

    Yoder, Anne D.; Campbell, C. Ryan; Blanco, Marina B.; dos Reis, Mario; Ganzhorn, Jörg U.; Goodman, Steven M.; Hunnicutt, Kelsie E.; Larsen, Peter A.; Kappeler, Peter M.; Rasoloarison, Rodin M.; Ralison, José M.; Swofford, David L.; Weisrock, David W.

    2016-01-01

    Phylogeographic analysis can be described as the study of the geological and climatological processes that have produced contemporary geographic distributions of populations and species. Here, we attempt to understand how the dynamic process of landscape change on Madagascar has shaped the distribution of a targeted clade of mouse lemurs (genus Microcebus) and, conversely, how phylogenetic and population genetic patterns in these small primates can reciprocally advance our understanding of Madagascar's prehuman environment. The degree to which human activity has impacted the natural plant communities of Madagascar is of critical and enduring interest. Today, the eastern rainforests are separated from the dry deciduous forests of the west by a large expanse of presumed anthropogenic grassland savanna, dominated by the Family Poaceae, that blankets most of the Central Highlands. Although there is firm consensus that anthropogenic activities have transformed the original vegetation through agricultural and pastoral practices, the degree to which closed-canopy forest extended from the east to the west remains debated. Phylogenetic and population genetic patterns in a five-species clade of mouse lemurs suggest that longitudinal dispersal across the island was readily achieved throughout the Pleistocene, apparently ending at ∼55 ka. By examining patterns of both inter- and intraspecific genetic diversity in mouse lemur species found in the eastern, western, and Central Highland zones, we conclude that the natural environment of the Central Highlands would have been mosaic, consisting of a matrix of wooded savanna that formed a transitional zone between the extremes of humid eastern and dry western forest types. PMID:27432945

  18. Comparison of Marine Spatial Planning Methods in Madagascar Demonstrates Value of Alternative Approaches

    PubMed Central

    Allnutt, Thomas F.; McClanahan, Timothy R.; Andréfouët, Serge; Baker, Merrill; Lagabrielle, Erwann; McClennen, Caleb; Rakotomanjaka, Andry J. M.; Tianarisoa, Tantely F.; Watson, Reg; Kremen, Claire

    2012-01-01

    The Government of Madagascar plans to increase marine protected area coverage by over one million hectares. To assist this process, we compare four methods for marine spatial planning of Madagascar's west coast. Input data for each method was drawn from the same variables: fishing pressure, exposure to climate change, and biodiversity (habitats, species distributions, biological richness, and biodiversity value). The first method compares visual color classifications of primary variables, the second uses binary combinations of these variables to produce a categorical classification of management actions, the third is a target-based optimization using Marxan, and the fourth is conservation ranking with Zonation. We present results from each method, and compare the latter three approaches for spatial coverage, biodiversity representation, fishing cost and persistence probability. All results included large areas in the north, central, and southern parts of western Madagascar. Achieving 30% representation targets with Marxan required twice the fish catch loss than the categorical method. The categorical classification and Zonation do not consider targets for conservation features. However, when we reduced Marxan targets to 16.3%, matching the representation level of the “strict protection” class of the categorical result, the methods show similar catch losses. The management category portfolio has complete coverage, and presents several management recommendations including strict protection. Zonation produces rapid conservation rankings across large, diverse datasets. Marxan is useful for identifying strict protected areas that meet representation targets, and minimize exposure probabilities for conservation features at low economic cost. We show that methods based on Zonation and a simple combination of variables can produce results comparable to Marxan for species representation and catch losses, demonstrating the value of comparing alternative approaches during

  19. Analysis of Patterns of Bushmeat Consumption Reveals Extensive Exploitation of Protected Species in Eastern Madagascar

    PubMed Central

    Jenkins, Richard K. B.; Keane, Aidan; Rakotoarivelo, Andrinajoro R.; Rakotomboavonjy, Victor; Randrianandrianina, Felicien H.; Razafimanahaka, H. Julie; Ralaiarimalala, Sylvain R.; Jones, Julia P. G.

    2011-01-01

    Understanding the patterns of wild meat consumption from tropical forests is important for designing approaches to address this major threat to biodiversity and mitigate potential pathways for transmission of emerging diseases. Bushmeat consumption has been particularly poorly studied in Madagascar, one of the world's hottest biodiversity hotspots. Studying bushmeat consumption is challenging as many species are protected and researchers must consider the incentives faced by informants. Using interviews with 1154 households in 12 communes in eastern Madagascar, as well as local monitoring data, we investigated the importance of socio-economic variables, taste preference and traditional taboos on consumption of 50 wild and domestic species. The majority of meals contain no animal protein. However, respondents consume a wide range of wild species and 95% of respondents have eaten at least one protected species (and nearly 45% have eaten more than 10). The rural/urban divide and wealth are important predictors of bushmeat consumption, but the magnitude and direction of the effect varies between species. Bushmeat species are not preferred and are considered inferior to fish and domestic animals. Taboos have provided protection to some species, particularly the Endangered Indri, but we present evidence that this taboo is rapidly eroding. By considering a variety of potential influences on consumption in a single study we have improved understanding of who is eating bushmeat and why. Evidence that bushmeat species are not generally preferred meats suggest that projects which increase the availability of domestic meat and fish may have success at reducing demand. We also suggest that enforcement of existing wildlife and firearm laws should be a priority, particularly in areas undergoing rapid social change. The issue of hunting as an important threat to biodiversity in Madagascar is only now being fully recognised. Urgent action is required to ensure that heavily hunted

  20. Stone tools and foraging in northern Madagascar challenge Holocene extinction models

    PubMed Central

    Dewar, Robert E.; Radimilahy, Chantal; Wright, Henry T.; Jacobs, Zenobia; Kelly, Gwendolyn O.; Berna, Francesco

    2013-01-01

    Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar’s known occupational history, and thus the time during which people exploited Madagascar’s environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. 14C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton’i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050–1350, by 14C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. 14C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact. PMID:23858456

  1. The GLOBE/Madagascar Malaria Project: Creating Student/Educator/Scientist Partnerships With Regional Impact

    NASA Astrophysics Data System (ADS)

    Brooks, D.; Boger, R.; Rafalimanana, A.

    2006-05-01

    Malaria is a parasitic disease spread by mosquitoes in the genus Anopheles. It causes more than 300,000,000 acute illnesses and more than one million deaths annually, including the death of one African child every 30 seconds. Recent epidemiological trends include increases in malaria mortality and the emergence of drug-resistant parasites. Some experts believe that predicted climate changes during the 21st century will bring malaria to areas where it is not now common. The GLOBE Program is currently collaborating with students, educators, scientists, health department officials, and government officials in Madagascar to develop a program that combines existing GLOBE protocols for measuring atmospheric and water quality parameters with a new protocol for collecting and identifying mosquito larvae at the genus (Anopheles and non-Anopheles) level. There are dozens of Anopheles species and sub-species that are adapted to a wide range of micro-environmental conditions encountered in Madagascar's variable climate. Local data collection is essential because mosquitoes typically spend their entire lives within a few kilometers of their breeding sites. The GLOBE Program provides an ideal framework for such a project because it offers a highly structured system for defining experiment protocols that ensure consistent procedures, a widely dispersed network of observing sites, and a centralized data collection and reporting system. Following a series of training activities in 2005, students in Madagascar are now beginning to collect data. Basic environmental parameters and first attempts at larvae collection and identification are presented. Results from this project can be used to increase public awareness of malaria, to provide new scientific data concerning environmental impacts on mosquito breeding, and to provide better information for guiding effective mitigation strategies. Problems encountered include difficulties in visiting and communicating with remote school sites

  2. Mechanism of Interannual Variability in Western Boundary Currents along Madagascar and their Relation with the ENSO

    NASA Astrophysics Data System (ADS)

    Yamagami, Y.; Tozuka, T.

    2016-02-01

    The South Equatorial Current (SEC) in the Indian Ocean bifurcates at the east coast of Madagascar into the Northeast and Southeast Madagascar Currents (NEMC and SEMC, respectively). The NEMC and SEMC transport anomalies influence eddy activities in the Mozambique Channel and the southwest of Madagascar. These eddies not only influence the ecosystems in the Mozambique Channel, but may also modulate the global thermohaline circulation by affecting water mass exchange between the Indian and Atlantic Oceans through their influence on the Agulhas Ring shedding. Therefore, to enhance understanding of the dynamical connection between NEMC and SEMC variability and physical and biological variability in their downstream, the dynamical mechanism of interannual variations in the NEMC and SEMC transport is investigated. The NEMC (SEMC) transport in reanalysis data undergoes interannual variations with the peak-to-peak amplitude of about 15 (6) Sv. The time-dependent Island Rule indicates that the above interannual variations are due to the responses to anomalous meridional interior transport. This is a result of westward popagating Rossby waves generated by Ekman pumping anomalies over 60°E - 90°E. It is shown that the NEMC and SEMC transports are correlated with the Niño 3.4 index with 5-15 months lag and ENSO-related diabatic heating anomalies over the western tropical Pacific generate wind stress curl anomalies over the southern Indian Ocean. These wind stress anomalies are also modified by local SST anomalies in the southeastern Indian Ocean. The above influences from the local and remote SST anomalies are confirmed by atmospheric general circulation model experiments.

  3. Hunting, Exotic Carnivores, and Habitat Loss: Anthropogenic Effects on a Native Carnivore Community, Madagascar.

    PubMed

    Farris, Zach J; Golden, Christopher D; Karpanty, Sarah; Murphy, Asia; Stauffer, Dean; Ratelolahy, Felix; Andrianjakarivelo, Vonjy; Holmes, Christopher M; Kelly, Marcella J

    2015-01-01

    The wide-ranging, cumulative, negative effects of anthropogenic disturbance, including habitat degradation, exotic species, and hunting, on native wildlife has been well documented across a range of habitats worldwide with carnivores potentially being the most vulnerable due to their more extinction prone characteristics. Investigating the effects of anthropogenic pressures on sympatric carnivores is needed to improve our ability to develop targeted, effective management plans for carnivore conservation worldwide. Utilizing photographic, line-transect, and habitat sampling, as well as landscape analyses and village-based bushmeat hunting surveys, we provide the first investigation of how multiple forms of habitat degradation (fragmentation, exotic carnivores, human encroachment, and hunting) affect carnivore occupancy across Madagascar's largest protected area: the Masoala-Makira landscape. We found that as degradation increased, native carnivore occupancy and encounter rates decreased while exotic carnivore occupancy and encounter rates increased. Feral cats (Felis species) and domestic dogs (Canis familiaris) had higher occupancy than half of the native carnivore species across Madagascar's largest protected landscape. Bird and small mammal encounter rates were negatively associated with exotic carnivore occupancy, but positively associated with the occupancy of four native carnivore species. Spotted fanaloka (Fossa fossana) occupancy was constrained by the presence of exotic feral cats and exotic small Indian civet (Viverricula indica). Hunting was intense across the four study sites where hunting was studied, with the highest rates for the small Indian civet (mean=90 individuals consumed/year), the ring-tailed vontsira (Galidia elegans) (mean=58 consumed/year), and the fosa (Cryptoprocta ferox) (mean=31 consumed/year). Our modeling results suggest hunters target intact forest where carnivore occupancy, abundance, and species richness, are highest. These various

  4. Convergent evolution of chemical defense in poison frogs and arthropod prey between Madagascar and the Neotropics.

    PubMed

    Clark, Valerie C; Raxworthy, Christopher J; Rakotomalala, Valérie; Sierwald, Petra; Fisher, Brian L

    2005-08-16

    With few exceptions, aposematically colored poison frogs sequester defensive alkaloids, unchanged, from dietary arthropods. In the Neotropics, myrmicine and formicine ants and the siphonotid millipede Rhinotus purpureus are dietary sources for alkaloids in dendrobatid poison frogs, yet the arthropod sources for Mantella poison frogs in Madagascar remained unknown. We report GC-MS analyses of extracts of arthropods and microsympatric Malagasy poison frogs (Mantella) collected from Ranomafana, Madagascar. Arthropod sources for 11 "poison frog" alkaloids were discovered, 7 of which were also detected in microsympatric Mantella. These arthropod sources include three endemic Malagasy ants, Tetramorium electrum, Anochetus grandidieri, and Paratrechina amblyops (subfamilies Myrmicinae, Ponerinae, and Formicinae, respectively), and the pantropical tramp millipede R. purpureus. Two of these ant species, A. grandidieri and T. electrum, were also found in Mantella stomachs, and ants represented the dominant prey type (67.3% of 609 identified stomach arthropods). To our knowledge, detection of 5,8-disubstituted (ds) indolizidine iso-217B in T. electrum represents the first izidine having a branch point in its carbon skeleton to be identified from ants, and detection of 3,5-ds pyrrolizidine 251O in A. grandidieri represents the first ponerine ant proposed as a dietary source of poison frog alkaloids. Endemic Malagasy ants with defensive alkaloids (with the exception of Paratrechina) are not closely related to any Neotropical species sharing similar chemical defenses. Our results suggest convergent evolution for the acquisition of defensive alkaloids in these dietary ants, which may have been the critical prerequisite for subsequent convergence in poison frogs between Madagascar and the Neotropics.

  5. Influences on women's decision making about intrauterine device use in Madagascar.

    PubMed

    Gottert, Ann; Jacquin, Karin; Rahaivondrafahitra, Bakoly; Moracco, Kathryn; Maman, Suzanne

    2015-04-01

    We explored influences on decision making about intrauterine device (IUD) use among women in the Women's Health Project (WHP), managed by Population Services International in Madagascar. We conducted six small group photonarrative discussions (n=18 individuals) and 12 individual in-depth interviews with women who were IUD users and nonusers. All participants had had contact with WHP counselors in three sites in Madagascar. Data analysis involved creating summaries of each transcript, coding in Atlas.ti and then synthesizing findings in a conceptual model. We identified three stages of women's decision making about IUD use, and specific forms of social support that seemed helpful at each stage. During the first stage, receiving correct information from a trusted source such as a counselor conveys IUD benefits and corrects misinformation, but lingering fears about the method often appeared to delay method adoption among interested women. During the second stage, hearing testimony from satisfied users and receiving ongoing emotional support appeared to help alleviate these fears. During the third stage, accompaniment by a counselor or peer seemed to help some women gain confidence to go to the clinic to receive the IUD. Identifying and supplying the types of social support women find helpful at different stages of the decision-making process could help program managers better respond to women's staged decision-making process about IUD use. This qualitative study suggests that women in Madagascar perceive multiple IUD benefits but also fear the method even after misinformation is corrected, leading to a staged decision-making process about IUD use. Programs should identify and supply the types of social support that women find helpful at each stage of decision making. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. The epidemiological transition in Antananarivo, Madagascar: an assessment based on death registers (1900-2012).

    PubMed

    Masquelier, Bruno; Waltisperger, Dominique; Ralijaona, Osée; Pison, Gilles; Ravélo, Arsène

    2014-01-01

    Madagascar today has one of the highest life expectancies in sub-Saharan Africa, despite being among the poorest countries in the continent. There are relatively few detailed accounts of the epidemiological transition in this country due to the lack of a comprehensive death registration system at the national level. However, in Madagascar's capital city, death registration was established around the start of the 20th century and is now considered virtually complete. We provide an overview of trends in all-cause and cause-specific mortality in Antananarivo to document the timing and pace of the mortality decline and the changes in the cause-of-death structure. Death registers covering the period 1976-2012 were digitized and the population at risk of dying was estimated from available censuses and surveys. Trends for the period 1900-1976 were partly reconstructed from published sources. The crude death rate stagnated around 30‰ until the 1940s in Antananarivo. Mortality declined rapidly after the World War II and then resurged again in the 1980s as a result of the re-emergence of malaria and the collapse of Madagascar's economy. Over the past 30 years, impressive gains in life expectancy have been registered thanks to the unabated decline in child mortality, despite political instability, a lasting economic crisis and the persistence of high rates of chronic malnutrition. Progress in adult survival has been more modest because reductions in infectious diseases and diseases of the respiratory system have been partly offset by increases in cardiovascular diseases, neoplasms, and other diseases, particularly at age 50 years and over. The transition in Antananarivo has been protracted and largely dependent on anti-microbial and anti-parasitic medicine. The capital city now faces a double burden of communicable and non-communicable diseases. The ongoing registration of deaths in the capital generates a unique database to evaluate the performance of the health system and

  7. Seismic Investigations of the Crust and Upper Mantle Structure in Antarctica and Madagascar

    NASA Astrophysics Data System (ADS)

    Ramirez, Cristo

    In the three studies that form this dissertation, seismic data from Antarctica and Madagascar have been analyzed to obtain new insights into crustal structure and mantle flow. Until recently, there have been little seismic data available from these areas for interrogating Earth structure and processes. In Antarctica, I analyzed datasets from temporary deployments of broadband seismic stations in both East and West Antarctica. In Madagascar, I analyzed data from a temporary network of broadband stations, along with data from three permanent stations. The seismic data have been processed and modeled using a wide range of techniques to characterize crust and mantle structure. Crustal structure in the East Antarctic Craton resembles Precambrian terrains around the world in its thickness and shear wave velocities. The West Antarctic Rift System has thinner crust, consistent with crustal thickness beneath other Cretaceous rifts. The Transantarctic Mountains show thickening of the crust from the costal regions towards the interior of the mountain range, and high velocities in the lower crust at several locations, possibly resulting from the Ferrar magmatic event. Ross Island and Marie Byrd Land Dome have elevated crustal Vp/Vs ratios, suggesting the presence of partial melt and/or volcaniclastic material within the crust. The pattern of seismic anisotropy in Madagascar is complex and cannot arise solely due to mantle flow from the African superplume, as previously proposed. To explain the complex pattern of anisotropy, a combination of mechanisms needs to be invoked, including mantle flow from the African superplume, mantle flow from the Comoros hotspot, small scale upwelling in the mantle induced by lithospheric delamination, and fossil anisotropy in the lithospheric mantle along Precambrian shear zones.

  8. Evaluation of the influenza sentinel surveillance system in Madagascar, 2009–2014

    PubMed Central

    Rakotoarisoa, Alain; Randrianasolo, Laurence; Tempia, Stefano; Guillebaud, Julia; Razanajatovo, Norosoa; Randriamampionona, Lea; Piola, Patrice; Halm, Ariane

    2017-01-01

    Abstract Problem Evaluation of influenza surveillance systems is poor, especially in Africa. Approach In 2007, the Institut Pasteur de Madagascar and the Malagasy Ministry of Public Health implemented a countrywide system for the prospective syndromic and virological surveillance of influenza-like illnesses. In assessing this system’s performance, we identified gaps and ways to promote the best use of resources. We investigated acceptability, data quality, flexibility, representativeness, simplicity, stability, timeliness and usefulness and developed qualitative and/or quantitative indicators for each of these attributes. Local setting Until 2007, the influenza surveillance system in Madagascar was only operational in Antananarivo and the observations made could not be extrapolated to the entire country. Relevant changes By 2014, the system covered 34 sentinel sites across the country. At 12 sites, nasopharyngeal and/or oropharyngeal samples were collected and tested for influenza virus. Between 2009 and 2014, 177 718 fever cases were detected, 25 809 (14.5%) of these fever cases were classified as cases of influenza-like illness. Of the 9192 samples from patients with influenza-like illness that were tested for influenza viruses, 3573 (38.9%) tested positive. Data quality for all evaluated indicators was categorized as above 90% and the system also appeared to be strong in terms of its acceptability, simplicity and stability. However, sample collection needed improvement. Lessons learnt The influenza surveillance system in Madagascar performed well and provided reliable and timely data for public health interventions. Given its flexibility and overall moderate cost, this system may become a useful platform for syndromic and laboratory-based surveillance in other low-resource settings. PMID:28479639

  9. Evaluation of the influenza sentinel surveillance system in Madagascar, 2009-2014.

    PubMed

    Rakotoarisoa, Alain; Randrianasolo, Laurence; Tempia, Stefano; Guillebaud, Julia; Razanajatovo, Norosoa; Randriamampionona, Lea; Piola, Patrice; Halm, Ariane; Heraud, Jean-Michel

    2017-05-01

    Evaluation of influenza surveillance systems is poor, especially in Africa. In 2007, the Institut Pasteur de Madagascar and the Malagasy Ministry of Public Health implemented a countrywide system for the prospective syndromic and virological surveillance of influenza-like illnesses. In assessing this system's performance, we identified gaps and ways to promote the best use of resources. We investigated acceptability, data quality, flexibility, representativeness, simplicity, stability, timeliness and usefulness and developed qualitative and/or quantitative indicators for each of these attributes. Until 2007, the influenza surveillance system in Madagascar was only operational in Antananarivo and the observations made could not be extrapolated to the entire country. By 2014, the system covered 34 sentinel sites across the country. At 12 sites, nasopharyngeal and/or oropharyngeal samples were collected and tested for influenza virus. Between 2009 and 2014, 177 718 fever cases were detected, 25 809 (14.5%) of these fever cases were classified as cases of influenza-like illness. Of the 9192 samples from patients with influenza-like illness that were tested for influenza viruses, 3573 (38.9%) tested positive. Data quality for all evaluated indicators was categorized as above 90% and the system also appeared to be strong in terms of its acceptability, simplicity and stability. However, sample collection needed improvement. The influenza surveillance system in Madagascar performed well and provided reliable and timely data for public health interventions. Given its flexibility and overall moderate cost, this system may become a useful platform for syndromic and laboratory-based surveillance in other low-resource settings.

  10. Early Permian to Middle Jurassic rifting and sedimentation in East Africa and Madagascar

    NASA Astrophysics Data System (ADS)

    Hankel, O.

    1994-12-01

    Pre-drift sediments of Madagascar (Early Permian-Middle Jurassic) have been studied palynologically. These studies resulted in a more precise dating of individual stratigraphic units and the recognition of minor and major breaks in the succession. Palynostratigraphic and physical evidence of unconformities have been used to subdivide the pre-drift sediments into depositional cycles and to infer rifting events. A comparison with equivalent strata of Mozambique, Tanzania, Kenya, Ethiopia and Somalia shows a general correspondence and provides additional information for the construction of a generalized framework for the East African/Madagascan region which demonstrates the relationships between rifting and sedimentation and elucidates the prehistory of the break-up of Gondwana into a western and eastern fragment during the Middle Jurassic. The predrift succession of East Africa/Madagascar can be subdivided into two major sequences, a Karoo sequence (cycles 1 5, Asselian-early Smithian) and a transitional sequence (cycles 6 9, Ladinian-early Bajocian). The two sequences are separeted by a late Scythian to Anisian hiatus which indicates extensive uplift and erosion before a major rifting event initiated the resumption of sedimentation in the Ladinian. This Middle Triassic event marks the transition from the intracratonic rift stage to the pericratonic basin stage and correlates with a significant event in the Pangaean history, the transition from final coalescence to initial dispersal. The onset of the southward drift of Madagascar is believed to have occurred about 60 Ma later near the Aalenian-Bajocian boundary, contemporaneous with or immediately after the deposition of syntectonic sediments of cycle 9.

  11. Eddies and dipoles around South Madagascar and their large-scale impact

    NASA Astrophysics Data System (ADS)

    de Ruijter, W.; van Aken, H.; Beier, E.; Lutjeharms, J.; Matano, R.; Schouten, M.

    2003-04-01

    During a hydrographic cruise in March 2001 we encountered a dipole-like vortex structure directly southwest of Madagascar. The cruise formed part of the Agulhas Current Sources Experiment (ACSEX). Direct current observations using a LADCP showed that the dipole consisted of a deep reaching central jet, with over 20 cm/s speeds still at 2000 m depth, with two contra-rotating eddies on either side. Both had a size of about 250 km. An analysis of the TOPEX-POSEIDON/ERS altimeter dataset revealed the regular formation of dipoles around south Madagascar, where the East Madagascar Current (EMC) separates from the shelf. Between April 1995 and June 2000 sixteen such features could be identified, six of which were formed between August 1996 and May 1997 and five between July 1999 and June 2000. These periods of enhanced dipole formation coincided with the negative phases of the Indian Ocean Dipole/ El Niño cycles, suggesting a connection between these climate modes and the interannual variability in the periods of dipole formation. In the Mozambique Basin the eddy pairs behaved quite irregularly, with many of them splitting and interacting with other eddies in the region. The anticyclones then propagated mostly westward while the cyclone tracks diverged more between west and southwest and were influenced by the interaction with the Mozambique Ridge. The data indicate that the eddies carry their water along. At the observed scales one dipole per year would feed 8 Sv (1 Sv=10^6 m^3/s) of EMC-derived water into the Agulhas retroflection region. A very regular train of dipoles started in December 1999 and continued through 2000. They were spawned roughly at 2 month intervals, stayed remarkably coherent and triggered an unusually early retroflection of the Agulhas in late 2000. Thus, interannual variability originating in the equatorial climate modes of the Indian Ocean seems to result in variability of the Agulhas retroflection and associated ring shedding.

  12. Holocene Indian Ocean Cosmic Impacts: The Megatsunami Chevron Evidence From Madagascar

    NASA Astrophysics Data System (ADS)

    Masse, W.; Bryant, E.; Gusiakov, V.; Abbott, D.; Rambolamana, G.; Raza, H.; Courty, M.; Breger, D.; Gerard-Little, P.; Burckle, L.

    2006-12-01

    The 2.6 million year Quaternary period terrestrial physical record lacks definitive crater evidence for major regional catastrophic impacts by asteroids and comets other than the 10.5-km diameter Botsumtwi structure in Ghana and the 14.0-km diameter Zhamanshin structure in Kazakhstan [1] dating between about 900 and 1100 kya. Current cosmic impact rate models suggest that an average of between 3-6 globally catastrophic impacts should have occurred on the Earth during the Quaternary, along with several additional significant regional impacts in addition to Zhamanshin and Botsumtwi. These models and data indicate that the great majority of the "missing" major impact locations would likely have occurred in poorly studied oceanic settings. Only recently have Late Quaternary and Holocene period coastal paleo-megatsunami chevron deposits been defined in the Caribbean and along the western coasts of Australia, along with the suggestion that some may have been created by oceanic cosmic impacts in distinction to those caused by landslips, eruptions, and seismic events. We investigate the possibility that many or most megatsunami chevrons occurring along the southern coast of Madagascar were caused by two or more major Holocene Indian Ocean cosmic impacts. This hypothesis is based on an initial study of the worldwide archaeological and anthropological record, and the preliminary study of satellite images of the chevrons, selected Indian Ocean deep-sea cores, sea-floor bathymetry, and physical examination of the Madagascar deposits themselves. Candidate Indian Ocean impact structures are identified and correlated with the southern Madagascar megatsunami chevron deposits. [1] Masse, W.B. 2007 The Archaeology and Anthropology of Quaternary Period Cosmic Impact. In Bobrowsky, P.T. & Rickman, H. (eds.)Comets/Asteroid Impacts and Human Society. Springer, Berlin (in press).

  13. Comparison of marine spatial planning methods in Madagascar demonstrates value of alternative approaches.

    PubMed

    Allnutt, Thomas F; McClanahan, Timothy R; Andréfouët, Serge; Baker, Merrill; Lagabrielle, Erwann; McClennen, Caleb; Rakotomanjaka, Andry J M; Tianarisoa, Tantely F; Watson, Reg; Kremen, Claire

    2012-01-01

    The Government of Madagascar plans to increase marine protected area coverage by over one million hectares. To assist this process, we compare four methods for marine spatial planning of Madagascar's west coast. Input data for each method was drawn from the same variables: fishing pressure, exposure to climate change, and biodiversity (habitats, species distributions, biological richness, and biodiversity value). The first method compares visual color classifications of primary variables, the second uses binary combinations of these variables to produce a categorical classification of management actions, the third is a target-based optimization using Marxan, and the fourth is conservation ranking with Zonation. We present results from each method, and compare the latter three approaches for spatial coverage, biodiversity representation, fishing cost and persistence probability. All results included large areas in the north, central, and southern parts of western Madagascar. Achieving 30% representation targets with Marxan required twice the fish catch loss than the categorical method. The categorical classification and Zonation do not consider targets for conservation features. However, when we reduced Marxan targets to 16.3%, matching the representation level of the "strict protection" class of the categorical result, the methods show similar catch losses. The management category portfolio has complete coverage, and presents several management recommendations including strict protection. Zonation produces rapid conservation rankings across large, diverse datasets. Marxan is useful for identifying strict protected areas that meet representation targets, and minimize exposure probabilities for conservation features at low economic cost. We show that methods based on Zonation and a simple combination of variables can produce results comparable to Marxan for species representation and catch losses, demonstrating the value of comparing alternative approaches during

  14. Evaluating ring-tailed lemurs (Lemur catta) from southwestern Madagascar for a genetic population bottleneck.

    PubMed

    Parga, Joyce A; Sauther, Michelle L; Cuozzo, Frank P; Jacky, Ibrahim Antho Youssouf; Lawler, Richard R

    2012-01-01

    In light of historical and recent anthropogenic influences on Malagasy primate populations, in this study ring-tailed lemur (Lemur catta) samples from two sites in southwestern Madagascar, Beza Mahafaly Special Reserve (BMSR) and Tsimanampetsotsa National Park (TNP), were evaluated for the genetic signature of a population bottleneck. A total of 45 individuals (20 from BMSR and 25 from TNP) were genotyped at seven microsatellite loci. Three methods were used to evaluate these populations for evidence of a historical bottleneck: M-ratio, mode-shift, and heterozygosity excess tests. Three mutation models were used for heterozygosity excess tests: the stepwise mutation model (SMM), two-phase model (TPM), and infinite allele model (IAM). M-ratio estimations indicated a potential bottleneck in both populations under some conditions. Although mode-shift tests did not strongly indicate a population bottleneck in the recent historical past when samples from all individuals were included, a female-only analysis indicated a potential bottleneck in TNP. Heterozygosity excess was indicated under two of the three mutation models (IAM and TPM), with TNP showing stronger evidence of heterozygosity excess than BMSR. Taken together, these results suggest that a bottleneck may have occurred among L. catta in southwestern Madagascar in the recent past. Given knowledge of how current major stochastic climatic events and human-induced change can negatively impact extant lemur populations, it is reasonable that comparable events in the historical past could have caused a population bottleneck. This evaluation additionally functions to highlight the continuing environmental and anthropogenic challenges faced by lemurs in southwestern Madagascar.

  15. Rotavirus genotypes in children in the community with diarrhea in Madagascar.

    PubMed

    Razafindratsimandresy, Richter; Heraud, Jean-Michel; Ramarokoto, Charles Emile; Rabemanantsoa, Sendraharimanana; Randremanana, Rindra; Andriamamonjy, Nelson Seta; Richard, Vincent; Reynes, Jean Marc

    2013-09-01

    In the context of the possible introduction of a preventive vaccine against rotaviruses in Madagascar, the G and P genotypes distribution of the rotaviruses circulating in the children in Madagascar was studied, and the presence of emerging genotypes and unusual strains were assessed. From February 2008 to May 2009, 1,679 stools specimens were collected from children ≤5 years old with diarrhea. ELISA was used for antigen detection, and molecular amplification of VP7 and VP4 gene fragments was used for genotyping. Rotavirus antigen was detected in 104 samples (6.2%). Partial sequences of VP7 and VP4 genes were obtained from 81 and 80 antigen-positive stools, respectively. The most frequent G and P types combinations detected were G9P[8] (n = 51; 64.6%), followed by G1P[8] (n = 15; 18.9%), and G1P[6] (n = 8; 10.1%). A few unusual G-P combinations, such as G4P[6] (n = 3; 3.8%), G9P[6] (n = 1; 1.3%), and G3P[9] reassortant feline human virus (n = 1; 1.3%) were identified. Both VP4 and VP7 sequences in one of the three G4P[6] isolates were closely related to those in porcine strains, and one was a reassortant human porcine virus. These findings give an overview of the strains circulating in Madagascar and should help public health authorities to define a vaccine strategy.

  16. Origin and evolutionary dynamics of Hepatitis B virus (HBV) genotype E in Madagascar.

    PubMed

    Lo Presti, Alessandra; Andriamandimby, Soa Fy; Lai, Alessia; Angeletti, Silvia; Cella, Eleonora; Mottini, Giovanni; Guarino, Michele Pier Luca; Balotta, Claudia; Galli, Massimo; Heraud, Jean-Michel; Zehender, Gianguglielmo; Ciccozzi, Massimo

    2017-02-01

    Africa is one of the endemic regions of HBV infection. In particular, genotype E is highly endemic in most of sub-Saharan Africa such as West African countries where it represents more than 90% of total infections. Madagascar, which is classified as a high endemic area for HBV and where the most prevalent genotype is E, might play a relevant role in the dispersion of this genotype due to its crucial position in the Indian Ocean. The aim of this study was to investigate the origin, population dynamics, and circulation of HBV-E genotype in Madagascar through high-resolution phylogenetic and phylodynamic approaches. The phylogenetic tree indicated that Malagasy isolates were intermixed and closely related with sequences mostly from West African countries. The Bayesian tree highlighted three statistically supported clusters of Malagasy strains which dated back to the years 1981 (95% HPD: 1971-1992), 1986 (95% HPD: 1974-1996), and 1989 (95% HPD: 1974-2001). Population dynamics analysis showed an exponential increase in the number of HBV-E infections approximately from the year 1975 until 2000s. The migration analysis was also performed and a dynamic pattern of gene flow was identified. In conclusion, this study confirms previous observation of HBV-E circulation in Africa and expands these findings at Madagascar demonstrating its recent introduction, and highlighting the role of the African countries in the spread of HBV-E genotype. Further studies on molecular epidemiology of HBV genotype E are needed to clarify the evolutionary history of this genotype.

  17. Shear velocity structure of the crust and upper mantle of Madagascar derived from surface wave tomography

    NASA Astrophysics Data System (ADS)

    Pratt, Martin J.; Wysession, Michael E.; Aleqabi, Ghassan; Wiens, Douglas A.; Nyblade, Andrew A.; Shore, Patrick; Rambolamanana, Gérard; Andriampenomanana, Fenitra; Rakotondraibe, Tsiriandrimanana; Tucker, Robert D.; Barruol, Guilhem; Rindraharisaona, Elisa

    2017-01-01

    The crust and upper mantle of the Madagascar continental fragment remained largely unexplored until a series of recent broadband seismic experiments. An island-wide deployment of broadband seismic instruments has allowed the first study of phase velocity variations, derived from surface waves, across the entire island. Late Cenozoic alkaline intraplate volcanism has occurred in three separate regions of Madagascar (north, central and southwest), with the north and central volcanism active until <1 Ma, but the sources of which remains uncertain. Combined analysis of three complementary surface wave methods (ambient noise, Rayleigh wave cross-correlations, and two-plane-wave) illuminate the upper mantle down to depths of 150 km. The phase-velocity measurements from the three methods for periods of 8-182 s are combined at each node and interpolated to generate the first 3-D shear-velocity model for sub-Madagascar velocity structure. Shallow (upper 10 km) low-shear-velocity regions correlate well with sedimentary basins along the west coast. Upper mantle low-shear-velocity zones that extend to at least 150 km deep underlie the north and central regions of recent alkali magmatism. These anomalies appear distinct at depths <100 km, suggesting that any connection between the zones lies at depths greater than the resolution of surface-wave tomography. An additional low-shear velocity anomaly is also identified at depths 50-150 km beneath the southwest region of intraplate volcanism. We interpret these three low-velocity regions as upwelling asthenosphere beneath the island, producing high-elevation topography and relatively low-volume magmatism.

  18. Analysis of patterns of bushmeat consumption reveals extensive exploitation of protected species in eastern Madagascar.

    PubMed

    Jenkins, Richard K B; Keane, Aidan; Rakotoarivelo, Andrinajoro R; Rakotomboavonjy, Victor; Randrianandrianina, Felicien H; Razafimanahaka, H Julie; Ralaiarimalala, Sylvain R; Jones, Julia P G

    2011-01-01

    Understanding the patterns of wild meat consumption from tropical forests is important for designing approaches to address this major threat to biodiversity and mitigate potential pathways for transmission of emerging diseases. Bushmeat consumption has been particularly poorly studied in Madagascar, one of the world's hottest biodiversity hotspots. Studying bushmeat consumption is challenging as many species are protected and researchers must consider the incentives faced by informants. Using interviews with 1154 households in 12 communes in eastern Madagascar, as well as local monitoring data, we investigated the importance of socio-economic variables, taste preference and traditional taboos on consumption of 50 wild and domestic species. The majority of meals contain no animal protein. However, respondents consume a wide range of wild species and 95% of respondents have eaten at least one protected species (and nearly 45% have eaten more than 10). The rural/urban divide and wealth are important predictors of bushmeat consumption, but the magnitude and direction of the effect varies between species. Bushmeat species are not preferred and are considered inferior to fish and domestic animals. Taboos have provided protection to some species, particularly the Endangered Indri, but we present evidence that this taboo is rapidly eroding. By considering a variety of potential influences on consumption in a single study we have improved understanding of who is eating bushmeat and why. Evidence that bushmeat species are not generally preferred meats suggest that projects which increase the availability of domestic meat and fish may have success at reducing demand. We also suggest that enforcement of existing wildlife and firearm laws should be a priority, particularly in areas undergoing rapid social change. The issue of hunting as an important threat to biodiversity in Madagascar is only now being fully recognised. Urgent action is required to ensure that heavily hunted

  19. New Material of Beelzebufo, a Hyperossified Frog (Amphibia: Anura) from the Late Cretaceous of Madagascar

    PubMed Central

    Evans, Susan E.; Groenke, Joseph R.; Jones, Marc E. H.; Turner, Alan H.; Krause, David W.

    2014-01-01

    The extant anuran fauna of Madagascar is exceptionally rich and almost completely endemic. In recent years, many new species have been described and understanding of the history and relationships of this fauna has been greatly advanced by molecular studies, but very little is known of the fossil history of frogs on the island. Beelzebufo ampinga, the first named pre-Holocene frog from Madagascar, was described in 2008 on the basis of numerous disarticulated cranial and postcranial elements from the Upper Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. These specimens documented the presence of a hyperossified taxon that differed strikingly from extant Malagasy frogs in its large size and heavy coarse cranial exostosis. Here we describe and analyse new, articulated, and more complete material of the skull, vertebral column, and hind limb, as well as additional isolated elements discovered since 2008. μCT scans allow a detailed understanding of both internal and external morphology and permit a more accurate reconstruction. The new material shows Beelzebufo to have been even more bizarre than originally interpreted, with large posterolateral skull flanges and sculptured vertebral spine tables. The apparent absence of a tympanic membrane, the strong cranial exostosis, and vertebral morphology suggest it may have burrowed during seasonally arid conditions, which have been interpreted for the Maevarano Formation from independent sedimentological and taphonomic evidence. New phylogenetic analyses, incorporating both morphological and molecular data, continue to place Beelzebufo with hyloid rather than ranoid frogs. Within Hyloidea, Beelzebufo still groups with the South American Ceratophryidae thus continuing to pose difficulties with both biogeographic interpretations and prior molecular divergence dates. PMID:24489877

  20. A new Gephyromantis (Phylacomantis) frog species from the pinnacle karst of Bemaraha, western Madagascar

    PubMed Central

    Crottini, Angelica; Glaw, Frank; Casiraghi, Maurizio; Jenkins, Richard K.B.; Mercurio, Vincenzo; Randrianantoandro, Christian; Randrianirina, Jasmin E.; Andreone, Franco

    2011-01-01

    Abstract We describe a new mantellid frog of the subfamily Mantellinae from the karstic Bemaraha Plateau, western Madagascar. The new species belongs to the genus Gephyromantis, subgenus Phylacomantis, which previously included Gephyromantis azzurrae, Gephyromantis corvus and Gephyromantis pseudoasper. Gephyromantis atsingy sp. n. has a snout-vent length of 35–43 mm and is a scansorial frog living among the Tsingy de Bemaraha pinnacles and inside the caves present in the area. A morphological analysis and biomolecular comparison revealed the degree of differentiation between these four species of the Phylacomantis subgenus.The new species seems to be endemic to Tsingy de Bemaraha. PMID:21594161

  1. Long-term impacts of logging on forest diversity in Madagascar

    PubMed Central

    Brown, Kerry A.; Gurevitch, Jessica

    2004-01-01

    Ecological perturbations can either be necessary for maintaining tropical forest diversity or responsible for its decline, depending on the scale, nature, and frequency of the disturbance. Anthropogenic disturbances such as logging and subsistence agriculture may promote the establishment of nonnative, invasive plant species, potentially affecting forest structure and diversity even long after the perturbation has ceased. We investigated the impacts of logging 50 and 150 years ago on tropical forest vegetation in Madagascar, a “hotspot” of biodiversity. Logging was the overriding factor influencing establishment of nonnative plants. Sites once logged never recovered native species diversity because of the dominance and persistence of invasive species. PMID:15067121

  2. Oxygen isotope systematics of gem corundum deposits in Madagascar: relevance for their geological origin

    NASA Astrophysics Data System (ADS)

    Giuliani, Gaston; Fallick, Anthony; Rakotondrazafy, Michel; Ohnenstetter, Daniel; Andriamamonjy, Alfred; Ralantoarison, Théogène; Rakotosamizanany, Saholy; Razanatseheno, Marie; Offant, Yohann; Garnier, Virginie; Dunaigre, Christian; Schwarz, Dietmar; Mercier, Alain; Ratrimo, Voahangy; Ralison, Bruno

    2007-02-01

    The oxygen isotopic composition of gem corundum was measured from 22 deposits and occurrences in Madagascar to provide a gemstone geological identification and characterization. Primary corundum deposits in Madagascar are hosted in magmatic (syenite and alkali basalt) and metamorphic rocks (gneiss, cordieritite, mafic and ultramafic rocks, marble, and calc-silicate rocks). In both domains the circulation of fluids, especially along shear zones for metamorphic deposits, provoked in situ transformation of the corundum host rocks with the formation of metasomatites such as phlogopite, sakenite, and corundumite. Secondary deposits (placers) are the most important economically and are contained in detrital basins and karsts. The oxygen isotopic ratios (18O/16O) of ruby and sapphire from primary deposits are a good indicator of their geological origin and reveal a wide range of δ18O (Vienna Standard Mean Ocean Water) between 1.3 and 15.6‰. Metamorphic rubies are defined by two groups of δ18O values in the range of 1.7 to 2.9‰ (cordieritite) and 3.8 to 6.1‰ (amphibolite). “Magmatic” rubies from pyroxenitic xenoliths contained in the alkali basalt of Soamiakatra have δ18O values ranging between 1.3 and 4.7‰. Sapphires are classified into two main groups with δ18O in the range of 4.7 to 9.0‰ (pyroxenite and feldspathic gneiss) and 10.7 to 15.6‰ (skarn in marble from Andranondambo). The δ18O values for gem corundum from secondary deposits have a wide spread between -0.3 and 16.5‰. The ruby and sapphire found in placers linked to alkali basalt environments in the northern and central regions of Madagascar have consistent δ18O values between 3.5 and 6.9‰. Ruby from the placers of Vatomandry and Andilamena has δ18O values of 5.9‰, and between 0.5 and 4.0‰, respectively. The placers of the Ilakaka area are characterized by a huge variety of colored sapphires and rubies, with δ18O values between -0.3 and 16.5‰, and their origin is debated. A

  3. Analysis of agency relationships in the design and implementation process of the equity fund in Madagascar.

    PubMed

    Honda, Ayako

    2015-02-04

    There are large gaps in the literature relating to the implementation of user fee policy and fee exemption measures for the poor, particularly on how such schemes are implemented and why many have not produced expected outcomes. In October 2003, Madagascar instituted a user fee exemption policy which established "equity funds" at public health centres, and used medicine sales revenue to subsidise the cost of medicine for the poor. This study examines the policy design and implementation process of the equity fund in Madagascar in an attempt to explore factors influencing the poor equity outcomes of the scheme. This study applied an agency-incentive framework to investigate the equity fund policy design and implementation practices. It analysed agency relationships established during implementation; examined incentive structures given to the agency relationships in the policy design; and considered how incentive structures were shaped and how agents responded in practice. The study employed a case-study approach with in-depth analysis of three equity fund cases in Madagascar's Boeny region. Policy design problems, triggering implementation problems, caused poor equity performance. These problems were compounded by the re-direction of policy objectives by health administrators and strong involvement of the administrators in the implementation of policy. The source of the policy design and implementation failure was identified as a set of principal-agent problems concerning: monitoring mechanisms; facility-based fund management; and the nature and level of community participation. These factors all contributed to the financial performance of the fund receiving greater attention than its ability to financially protect the poor. The ability of exemption policies to protect the poor from user fees can be found in the details of the policy design and implementation; and implications of the policy design and implementation in a specific context determine whether a policy

  4. Chemical composition of Melicope belahe (Baill.) T. G. Hartley (Rutaceae) leaf essential oil from Madagascar.

    PubMed

    Rabehaja, Delphin J R; Garcia, Gabriel; Charmillon, Julie-Marie; Désiré, Odile; Paoli, Mathieu; Ramanoelina, Panja A R; Tomi, Félix

    2017-01-01

    Melicope belahe (Baill.) T.G. Hartley (Rutaceae) is an endemic species to Madagascar. The chemical composition of leaf essential oil is reported for the first time. A sample was extracted by hydrodistillation and analysis was carried out by combination of chromatographic (GC), spectroscopic and spectrometric (MS, (13)C NMR) techniques. In total, 56 compounds have been identified. The chemical composition was dominated by α-pinene (42.6%) followed by linalool (6.2%) and (E)-β-caryophyllene (5.2%).

  5. [Madagascar: public health situation on the "Big Island" at the beginning of the 21st century].

    PubMed

    Andrianarisoa, A C E; Rakotoson, J; Randretsa, M; Rakotondravelo, S; Rakotoarimanana, R D; Rakotomizao, J; Aubry, P

    2007-02-01

    The main public health issue in Madagascar at the beginning of the 21st century still involves transmissible infectious diseases including re-emerging diseases such as bubonic plague and emerging diseases such as HIV/AIDS, dengue fever and Chikungunya virus infection. Health and hygiene especially access to clean water is still poor especially in rural areas. No improvement in the public health situation with regard to malaria, schistomosomiais or cysticercosis as well as non-infectious diseases such as protein-energy malnutrition is expected within the next decade.

  6. Descriptions and biological notes on three unusual mantellid tadpoles (Amphibia: Anura: Mantellidae) from southeastern Madagascar

    USGS Publications Warehouse

    Altig, R.; McDiarmid, R.W.

    2006-01-01

    The morphologies of three unusual tadpoles from slow-flowing, sandy-bottomed, rain forest streams in southeastern Madagascar are described. The large oral apparatus of the tadpole of Boophis picturatus Glaw, Vences, Andreone, and Vallan, 2001 lacks all keratinized structures and has an elaborately-folded lower labium with five, radially oriented, flattopped ridges. The tadpole of Mantidactylus guttulatus (Boulenger, 1881) lacks all keratinized mouthparts and has three immense papillae where the upper jaw normally occurs. The tadpole of Mantidactylus lugubris (Dumeril, 1853) has an ornate oral apparatus involving greatly hypertrophied derivatives of jaw serrations and unique structures on the lower labium that resemble labial teeth.

  7. Analyse macro-sociolinguistique d'une situation de diglossie: le cas de Madagascar (A Macro-Sociolinguistic Analysis of a Diglossic Situation: The Case of Madagascar). Publication H-6.

    ERIC Educational Resources Information Center

    Rambelo, Michel

    The languages used in Madagascar are examined from the following perspectives: the linguistic varieties and functions socially recognized at the community level; the oppositions and complementarities that have become established between languages in contact; and the speakers' attitudes toward those varieties. The report focuses on the following…

  8. Isolation of 22 new Haliaeetus microsatellite loci and their characterization in the critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) and three other Haliaeetus eagle species

    USGS Publications Warehouse

    Tingay, R.E.; Dawson, D.A.; Pandhal, J.; Clarke, M.L.; David, V.A.; Hailer, F.; Culver, M.

    2007-01-01

    We isolated a total of 22 microsatellite loci from two Haliaeetus species: the Madagascar fish-eagle (Haliaeetus vociferoides) and the bald eagle (Haliaeetus leucocephalus). Five loci were monomorphic in both the Madagascar fish-eagle (n = 24-43) and the bald eagle (n = 2-8) but were found to be polymorphic in other Haliaeetus species. Haliaeetus loci have proved useful for investigating gene flow in Haliaeetus and Aquila eagles. Ten loci were polymorphic in the critically endangered Madagascar fish-eagle and will be used to investigate the genetic population structure and mating system in this species. ?? 2007 The Authors.

  9. Anatomical descriptions of silicified woods from Madagascar and Indonesia by scanning electron microscopy.

    PubMed

    Yoon, Chul Jong; Kim, Ki Woo

    2008-10-01

    Fine structure and tissue substitution by minerals were investigated in silicified woods from Madagascar and Indonesia by scanning electron microscopy and X-ray microanalysis. The silicified woods maintained the exterior morphology of once grown trees and showed typical inner structures of conifers. Radial planes of the silicified wood from Madagascar revealed tracheids as a major component of the axial system in the secondary xylem. Tracheids were mainly characterized by numerous bordered pits where a thickening in the middle (torus) was surrounded with the membrane (margo). The torus appeared to contrast with the fibrillar network of the margo. As a component of the axial system in the secondary phloem, sieve elements were found to have many sieve pores that were filled with seemingly crystalline materials. To correlate the colors of the silicified wood from Indonesia with elemental composition, energy-dispersive X-ray spectrometry was employed in this study. Silicon was present as a basic component of the silicified wood. Calcium and iron were detected from red-colored regions, whereas magnesium was found in blue-colored regions. These results suggest that tissues of silicified woods had been substituted by minerals over the past period, while retaining the inherent morphology of the tree species. Scanning electron microscopy and X-ray microanalysis could be applied to unravel structural details and composition of plant fossils in palaeobotany.

  10. Key odorants in cured Madagascar vanilla beans (Vanilla planiforia) of differing bean quality.

    PubMed

    Takahashi, Makoto; Inai, Yoko; Miyazawa, Norio; Kurobayashi, Yoshiko; Fujita, Akira

    2013-01-01

    The odor-active volatiles in Madagascar vanilla beans (Vanilla planiforia) of two grades, red whole beans as standard quality and cuts beans as substandard quality, were characterized by instrumental and sensory analyses. The higher contents of vanillin and β-damascenone in red whole beans than in cuts beans respectively contributed to significant differences in the sweet and dried fruit-like notes, while the higher contents of guaiacol and 3-phenylpropanoic acid in cuts beans than in red whole beans respectively contributed to significant differences in the phenolic and metallic notes. A sensory evaluation to compare red whole beans and their reconstituted aroma characterized both samples as being similar, while in respect of the phenolic note, the reconstituted aroma significantly differed from the reconstituted aroma with guaiacol added at the concentration ratio of vanillin and guaiacol in cuts beans. It is suggested from these results that the concentration ratio of vanillin and guaiacol could be used as an index for the quality of Madagascar vanilla beans.

  11. Multivariate analysis of management and biosecurity practices in smallholder pig farms in Madagascar

    PubMed Central

    Costard, S.; Porphyre, V.; Messad, S.; Rakotondrahanta, S.; Vidon, H.; Roger, F.; Pfeiffer, D.U.

    2009-01-01

    A cross-sectional study was carried out in 2005 and 2006 in three geographical areas of Madagascar to investigate and differentiate swine farm management and biosecurity practices in smallholder farming communities. Questionnaire data from a total of 709 pig farms were analysed using multiple factor analysis (MFA) and hierarchical cluster analysis (HCA). Variables describing management and biosecurity practices were organised into five groups: structure of the farm, animal-contacts, person- and vehicle-contacts, feeding, and sanitary aspects. In general, few biosecurity measures were implemented in the pig farms included in the study. Regional differences in management and biosecurity practices emerged from the MFA and were mainly due to, in order of decreasing importance: structure of the farm, sanitary aspects, feeding and animal-contacts and, to a lesser extent, person- and vehicle-contacts. HCA resulted in the differentiation of four distinct types of farms in each of two study areas, Arivonimamo and Marovoay, while no grouping could be identified amongst farms in Ambatondrazaka area. The characterisation of the different types of smallholder pig farms will allow adapting recommendations on husbandry practices and control measures in pig farms of these regions of Madagascar. The development of tailored recommendations is essential for Malagasy smallholders who have limited resources and need to make evidence-based management changes to reduce the risk of contagious diseases in their herds. PMID:19781801

  12. Primates as Predictors of Mammal Community Diversity in the Forest Ecosystems of Madagascar

    PubMed Central

    Muldoon, Kathleen M.; Goodman, Steven M.

    2015-01-01

    The geographic distribution of species is the typical metric for identifying priority areas for conservation. Since most biodiversity remains poorly studied, a subset of charismatic species, such as primates, often stand as surrogates for total biodiversity. A central question is therefore, how effectively do primates predict the pooled species richness of other mammalian taxa? We used lemurs as indicator species to predict total non-primate mammal community richness in the forest ecosystems of Madagascar. We combine environmental and species occurrence data to ascertain the extent to which primate diversity can predict (1) non-primate mammal α-diversity (species richness), (2) non-primate complementarity, and (3) non-primate β-diversity (species turnover). Our results indicate that primates are effective predictors of non-primate mammal community diversity in the forest ecosystems of Madagascar after controlling for habitat. When individual orders of mammals are considered, lemurs effectively predict the species richness of carnivorans and rodents (but not afrosoricids), complementarity of rodents (but not carnivorans or afrosoricids), and all individual components of β-diversity. We conclude that lemurs effectively predict total non-primate community richness. However, surrogate species alone cannot achieve complete representation of biodiversity. PMID:26334525

  13. Endemic Amorphophallus (Araceae) from Madagascar: a revised key, a new species and molecular phylogeny.

    PubMed

    Hetterscheid, Wilbert L A; Claudel, Cyrille

    2014-12-01

    Since the revision of Amorphophallus of Madagascar (Bot Jahrb Syst 121(1):1-17, 1999) several additional new species have been described. The recent discovery of another new species promted the preparation of a revised key as well as the description of the new species. Amorphophallus hildebrandtii, never restudied since its analysis by Engler in 1881, has been refound and restudied. Meanwhile molecular phylogenetic studies have provided new insights in the relationships of the endemic Madagascan species. The new species Amorphophallus perrieri is described. A new revised key to the endemic Amorphophallus species of Madagascar is provided. An emended description of A. hildebrandtii is provided. A molecular phylogeny of the endemic Madagascan species of Amorphophallus is provided. The enigmatic character of a very short spadix in A. hildebrandtii has been confirmed, after it was thought for many years that it was artificially shorter in the holotype specimen than in nature. This was suggested by the fact that the spadix of the holotype is broken. The monophyletic character of the Madagascan endemic species clade remained unchallenged after analysis including all new species discovered recently, incl. the new species presented in this paper.

  14. Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar.

    PubMed

    Tollenaere, C; Rahalison, L; Ranjalahy, M; Duplantier, J-M; Rahelinirina, S; Telfer, S; Brouat, C

    2010-06-01

    In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected at high bacterial dose (more than 10⁵ bacteria injected), rats from the plague focus died mainly within 3-5 days and produced specific antibodies, whereas after low-dose infection (< 5,000 bacteria), delayed mortality was observed and surviving seronegative rats were not uncommon. These results concerning plague resistance level and the course of infection in the black rat would contribute to a better understanding of plague circulation in Madagascar.

  15. Rural livelihoods and access to natural capital: Differences between migrants and non-migrants in Madagascar

    PubMed Central

    Nawrotzki, Raphael J.; Hunter, Lori M.; Dickinson, Thomas W.

    2013-01-01

    BACKGROUND Although natural resources play a central role in rural livelihoods across the globe, little research has explored the relationship between migration and natural capital use, particularly in combination with other livelihood capitals (i.e., human, social, financial and physical). OBJECTIVE Grounded in the rural livelihood framework, this paper explores the association between the livelihood capital availability, especially natural capital, for migrants and non-migrants in rural Madagascar. METHODS Data from the 2008/2009 Demographic and Health Survey are used in combination with satellite imagery of vegetation coverage (Normalized Difference Vegetation Index, NDVI) to proxy natural resources. Hierarchical multilevel models allow for inclusion of cross-level interactions between migrant status and proximate natural resources as determinants of the status of livelihood assets. RESULTS Three key findings emerge. First, higher levels of proximate natural resources are associated with greater financial, human, and social capital for both migrants and non-migrants. Second, migrants have, on average, greater financial, physical, human, and social capital than non-migrants, and urban-to-rural migrants do exceptionally well on all capital asset categories. Third, migrants residing in areas with higher levels of natural capital tend to have significantly higher levels of human capital (education). CONCLUSION Although we cannot examine livelihood strategies per se, the results suggest variation in livelihood potential among migrants and non-migrants in rural Madagascar, with migrants tending to have greater capital assets. In addition, access to natural resources is a central livelihood strategy. PMID:25364297

  16. Widespread presence of the pathogenic fungus Batrachochytrium dendrobatidis in wild amphibian communities in Madagascar

    PubMed Central

    Bletz, Molly C.; Rosa, Gonçalo M.; Andreone, Franco; Courtois, Elodie A.; Schmeller, Dirk S.; Rabibisoa, Nirhy H. C.; Rabemananjara, Falitiana C. E.; Raharivololoniaina, Liliane; Vences, Miguel; Weldon, Ché; Edmonds, Devin; Raxworthy, Christopher J.; Harris, Reid N.; Fisher, Matthew C.; Crottini, Angelica

    2015-01-01

    Amphibian chytridiomycosis, an emerging infectious disease caused by the fungus Batrachochytrium dendrobatidis (Bd), has been a significant driver of amphibian declines. While globally widespread, Bd had not yet been reported from within Madagascar. We document surveys conducted across the country between 2005 and 2014, showing Bd's first record in 2010. Subsequently, Bd was detected in multiple areas, with prevalence reaching up to 100%. Detection of Bd appears to be associated with mid to high elevation sites and to have a seasonal pattern, with greater detectability during the dry season. Lineage-based PCR was performed on a subset of samples. While some did not amplify with any lineage probe, when a positive signal was observed, samples were most similar to the Global Panzootic Lineage (BdGPL). These results may suggest that Bd arrived recently, but do not exclude the existence of a previously undetected endemic Bd genotype. Representatives of all native anuran families have tested Bd-positive, and exposure trials confirm infection by Bd is possible. Bd's presence could pose significant threats to Madagascar's unique “megadiverse” amphibians. PMID:25719857

  17. Defining spatial and temporal patterns of phylogeographic structure in Madagascar's iguanid lizards (genus Oplurus).

    PubMed

    Chan, Lauren M; Choi, Dean; Raselimanana, Achille P; Rakotondravony, Hery A; Yoder, Anne D

    2012-08-01

    Understanding the remarkably high species diversity and levels of endemism found among Madagascar's flora and fauna has been the focus of many studies. One hypothesis that has received much attention proposes that Quaternary climate fluctuations spurred diversification. While spatial patterns of distribution and phylogenetic relationships can provide support for biogeographic predictions, temporal estimates of divergence are required to determine the fit of these geospatial patterns to climatic or biogeographic mechanisms. We use multilocus DNA sequence data to test whether divergence times among Malagasy iguanid lizards of the subfamily Oplurinae are compatible with a hypotheses of Pliocene-Pleistocene diversification. We estimate the oplurine species tree and associated divergence times under a relaxed-clock model. In addition, we examine the phylogeographic structure and population divergence times within two sister species of Oplurus primarily distributed in the north-west and south-west of Madagascar (Oplurus cuvieri and Oplurus cyclurus, respectively). We find that divergence events among oplurine lineages occurred in the Oligocene and Miocene and are thus far older and incompatible with the hypothesis that recent climate fluctuations are related to current species diversity. However, the timing of intraspecific divergences and spatial patterns of population genetic structure within O. cuvieri and O. cyclurus suggest a role for both intrinsic barriers and recent climate fluctuations at population-level divergences. Integrating information across spatial and temporal scales allows us to identify and better understand the mechanisms generating patterns diversity.

  18. Prevalence of hepatitis B virus serologic markers in pregnant patients in Antananarivo, Madagascar.

    PubMed

    Randriamahazo, T R; Raherinaivo, A A; Rakotoarivelo, Z H; Contamin, B; Rakoto Alson, O A; Andrianapanalinarivo, H R; Rasamindrakotroka, A

    2015-01-01

    Hepatitis B virus (HBV) infection is a major public health problem in Madagascar. Its severity is related to the risk of chronicity, especially in case of neonatal contamination. Our objectives were to investigate the prevalence of HBV infection among pregnant patients at the Befelatanana obstetrics and gynecology teaching hospital department (BOGTH) by detecting HBsAg and to evaluate the risk of HBV mother to child transmission by screening for HBeAg. We conducted a 6-month prospective study in the BTHOGD from February 2012 to July 2012. All pregnant patients consulting for antenatal care were screened for HBV serologic markers. The prevalence of HBsAg was 1.9% (20 out 1050 screened patients). The average age was 26.51 years (25-30 years). Most patients tested were unaware of their hepatitis B status and only 0.38% had been vaccinated before pregnancy. Only 1 (5%) of the 20 patients with HBsAg was positive for HBeAg. Hepatitis B is very frequent in pregnant patients in Madagascar and it is recommended that all pregnant patients be routinely screened for HBsAg. This screening of maternal infection would allow applying prophylactic measures to neonates to decrease the risk of disease chronicity. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  19. Vast underestimation of Madagascar's biodiversity evidenced by an integrative amphibian inventory.

    PubMed

    Vieites, David R; Wollenberg, Katharina C; Andreone, Franco; Köhler, Jörn; Glaw, Frank; Vences, Miguel

    2009-05-19

    Amphibians are in decline worldwide. However, their patterns of diversity, especially in the tropics, are not well understood, mainly because of incomplete information on taxonomy and distribution. We assess morphological, bioacoustic, and genetic variation of Madagascar's amphibians, one of the first near-complete taxon samplings from a biodiversity hotspot. Based on DNA sequences of 2,850 specimens sampled from over 170 localities, our analyses reveal an extreme proportion of amphibian diversity, projecting an almost 2-fold increase in species numbers from the currently described 244 species to a minimum of 373 and up to 465. This diversity is widespread geographically and across most major phylogenetic lineages except in a few previously well-studied genera, and is not restricted to morphologically cryptic clades. We classify the genealogical lineages in confirmed and unconfirmed candidate species or deeply divergent conspecific lineages based on concordance of genetic divergences with other characters. This integrative approach may be widely applicable to improve estimates of organismal diversity. Our results suggest that in Madagascar the spatial pattern of amphibian richness and endemism must be revisited, and current habitat destruction may be affecting more species than previously thought, in amphibians as well as in other animal groups. This case study suggests that worldwide tropical amphibian diversity is probably underestimated at an unprecedented level and stresses the need for integrated taxonomic surveys as a basis for prioritizing conservation efforts within biodiversity hotspots.

  20. NASA-NOAA's Suomi NPP Satellite Cyclone Haruna Near Madagascar at Night

    NASA Image and Video Library

    2017-09-27

    This night-time image revealed Cyclone Haruna's massive eye before it made landfall in southwestern Madagascar. This image was taken from the VIIRS instrument that flies aboard the NASA-NOAA Suomi NPP satellite. The image was taken on Feb. 20 at 2242 UTC (5:42 p.m. EST/U.S.) and shows a clear eye, surrounded by very powerful thunderstorms. The bright lights of the Capital city of Antananarivo are seen in this image. The capital city lies about 300 nautical miles northwest of the storm's center. Haruna's center made landfall near Manombo, Madagascar around 0600 UTC (1 a.m. EST/U.S.) and its eye became cloud-filled quickly. For the entire storm history, visit NASA's Hurricane Page: www.nasa.gov/mission_pages/hurricanes/archives/2013/h2013... Text: Credit: Univ.of Wisconsin/NASA/NOAA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  1. The Role of Demography and Markets in Determining Deforestation Rates Near Ranomafana National Park, Madagascar

    PubMed Central

    Brooks, Christopher P.; Holmes, Christopher; Kramer, Karen; Barnett, Barry; Keitt, Timothy H.

    2009-01-01

    The highland forests of Madagascar are home to some of the world's most unique and diverse flora and fauna and to some of its poorest people. This juxtaposition of poverty and biodiversity is continually reinforced by rapid population growth, which results in increasing pressure on the remaining forest habitat in the highland region, and the biodiversity therein. Here we derive a mathematical expression for the subsistence of households to assess the role of markets and household demography on deforestation near Ranomafana National Park. In villages closest to urban rice markets, households were likely to clear less land than our model predicted, presumably because they were purchasing food at market. This effect was offset by the large number of migrant households who cleared significantly more land between 1989–2003 than did residents throughout the region. Deforestation by migrant households typically occurred after a mean time lag of 9 years. Analyses suggest that while local conservation efforts in Madagascar have been successful at reducing the footprint of individual households, large-scale conservation must rely on policies that can reduce the establishment of new households in remaining forested areas. PMID:19536282

  2. Affordability of emergency obstetric and neonatal care at public hospitals in Madagascar.

    PubMed

    Honda, Ayako; Randaoharison, Pierana Gabriel; Matsui, Mitsuaki

    2011-05-01

    Timely access to emergency obstetric care is necessary to save the lives of women experiencing complications at delivery, and for newborn babies. Out-of-pocket costs are one of the critical factors hindering access to such services in low- and middle-income countries. This study measured out-of-pocket costs for caesarean section and neonatal care at an urban tertiary public hospital in Madagascar, assessed affordability in relation to household expenditure and investigated where families found the money to cover these costs. Data were collected for 103 women and 73 newborns at the Centre Hospitalier Universitaire de Mahajanga in the Boeny region of Madagascar between September 2007 and January 2008. Out-of-pocket costs for caesarean section were catastrophic for middle and lower socio-economic households, and treatment for neonatal complications also created a big financial burden, with geographical and other financial barriers further limiting access to hospital care. This study identified 12 possible cases where the mother required an emergency caesarean section and her newborn required emergency care, placing a double burden on the household. In an effort to make emergency obstetric and neonatal care affordable and available to all, including those living in rural areas and those of medium and lower socio-economic status, well-designed financial risk protection mechanisms and a strong commitment by the government to mobilise resources to finance the country's health system are necessary.

  3. Miocene benthic foraminifera from Nosy Makamby and Amparafaka, Mahajanga Basin, northwestern Madagascar

    NASA Astrophysics Data System (ADS)

    Ramihangihajason, Tolotra N.; Andrianavalona, Tsiory H.; Razafimbelo, Rachel; Rahantarisoa, Lydia; Ali, Jason R.; Samonds, Karen E.

    2014-12-01

    Madagascar is well known for its fossil deposits and hosts one of the world's most important Upper Cretaceous terrestrial faunal sites (in the Mahajanga and Morondava Basins in the west and northwest of the island). Cenozoic marine fossils are also described from Madagascar, but these have received far less attention from the paleontological community, with most of this work dating from the 19th and early 20th centuries. Our study reports a new comprehensive microfossil assemblage from a Miocene sequence on the island of Nosy Makamby. After washing, sieving and sorting (∼30 kg), twenty-five genera of foraminifera were identified including Alveolina, Ammodiscus, Ammonia, Archaias, Bolivina, Borelis, Cassidulina, Cyclammina, Cycloforina, Dentalina, Elphidium, Hauerina, Lagena, Lepidocyclina, Nodosaria, Nonion, Nonionella, Peneroplis, Pyrgo, Quinqueloculina, Rhabdammina, Spirillina, Spirolina, Spiroloculina and Triloculina. Ostracods are found in association with the foraminifera, as well as many other macroinvertebrate fossils (including bivalves, gastropods, and echinoids) in addition to vertebrate fossils. Together, the assemblage indicates that during the late Miocene, Nosy Makamby was a tropical, near-shore environment, probably similar to that seen today. Furthermore, the existence of epiphytic foraminiferans (e.g., Elphidium) suggests that sea-grass beds were likely present.

  4. DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar

    PubMed Central

    Smith, M. Alex; Fisher, Brian L; Hebert, Paul D.N

    2005-01-01

    The role of DNA barcoding as a tool to accelerate the inventory and analysis of diversity for hyperdiverse arthropods is tested using ants in Madagascar. We demonstrate how DNA barcoding helps address the failure of current inventory methods to rapidly respond to pressing biodiversity needs, specifically in the assessment of richness and turnover across landscapes with hyperdiverse taxa. In a comparison of inventories at four localities in northern Madagascar, patterns of richness were not significantly different when richness was determined using morphological taxonomy (morphospecies) or sequence divergence thresholds (Molecular Operational Taxonomic Unit(s); MOTU). However, sequence-based methods tended to yield greater richness and significantly lower indices of similarity than morphological taxonomy. MOTU determined using our molecular technique were a remarkably local phenomenon—indicative of highly restricted dispersal and/or long-term isolation. In cases where molecular and morphological methods differed in their assignment of individuals to categories, the morphological estimate was always more conservative than the molecular estimate. In those cases where morphospecies descriptions collapsed distinct molecular groups, sequence divergences of 16% (on average) were contained within the same morphospecies. Such high divergences highlight taxa for further detailed genetic, morphological, life history, and behavioral studies. PMID:16214741

  5. Lemur responses to edge effects in the Vohibola III classified forest, Madagascar.

    PubMed

    Lehman, Shawn M; Rajaonson, Andry; Day, Sabine

    2006-03-01

    Forest edges are dynamic zones characterized by the penetration (to varying depths and intensities) of conditions from the surrounding environment (matrix) into the forest interior. Although edge effects influence many tropical organisms, they have not been studied directly in primates. Edge effects are particularly relevant to lemurs because of the highly fragmented forest landscapes found in Madagascar. In this study, data are presented regarding how the densities of six lemur species (Avahi laniger, Cheirogaleus major, Eulemur rubriventer, Hapalemur griseus griseus, Microcebus rufus, and Propithecus diadema edwardsi) varied between six 500-m interior transects and six 500-m edge transects in the Vohibola III Classified Forest in SE Madagascar. Diurnal (n = 433) and nocturnal (n = 128) lemur surveys were conducted during June-October 2003 and May-November 2004. A. laniger, E. rubriventer, and H. g. griseus exhibited a neutral edge response (no differences in densities between habitats). M. rufus and P. d. edwardsi had a positive edge response (higher densities in edge habitats), which may be related to edge-related variations in food abundance and quality. Positive edge responses by M. rufus and P. d. edwardsi may ultimately be detrimental due to edge-related anthropogenic factors (e.g., hunting by local people). The negative edge response exhibited by C. major (lower densities in edge habitats) may result from heightened ambient temperatures that inhibit torpor in edge habitats.

  6. Evaluation of the OnSite malaria rapid test performance in Miandrivazo, Madagascar.

    PubMed

    Ravaoarisoa, E; Andriamiandranoro, T; Raherinjafy, R; Jahevitra, M; Razanatsiorimalala, S; Andrianaranjaka, V; Randrianarivelojosia, M

    2017-10-01

    The performance of the malaria rapid diagnostic test OnSite-for detecting pan specific pLDH and Plasmodium falciparum specific HRP2 - was assessed during the malaria transmission peak period in Miandrivazo, in the southwestern part of Madagascar from April 20 to May 6, 2010. At the laboratory, the quality control OnSite Malaria Rapid Test according to the WHO/TDR/FIND method demonstrated that the test had good sensitivity. Of the 218 OnSite tests performed at the Miandrivazo Primary Health Center on patients with fever or a recent history of fever, four (1.8%, 95% CI: 0.6-4.9%) were invalid. Ninety four (43,1%) cases of malaria were confirmed by microscopy, of which 90 were P. falciparum malaria and 4 Plasmodium vivax malaria. With a Cohen's kappa coefficient of 0.94, the agreement between microscopy and OnSite is excellent. Compared with the rapid test CareStart™ commonly used within the public health structures in Madagascar, the sensitivity and specificity of the OnSite test were 97.9% and 96.8%.

  7. Interactions between plants and primates shape community diversity in a rainforest in Madagascar.

    PubMed

    Herrera, James P

    2016-07-01

    Models of ecological community assembly predict how communities of interacting organisms may be shaped by abiotic and biotic factors. Competition and environmental filtering are the predominant factors hypothesized to explain community assembly. This study tested the effects of habitat, phylogenetic and phenotypic trait predictors on species co-occurrence patterns and abundances, with the endemic primates of Madagascar as an empirical system. The abundance of 11 primate species was estimated along gradients of elevation, food resource abundance and anthropogenic habitat disturbance at local scales in south-east Madagascar. Community composition was compared to null models to test for phylogenetic and functional structure, and the effects of phylogenetic relatedness of co-occurring species, their trait similarity and environmental variables on species' abundances were tested using mixed models and quantile regressions. Resource abundance was the strongest predictor of community structure. Where food tree abundance was high, closely related species with similar traits dominated communities. High-elevation communities with lower food tree abundance consisted of species that were distantly related and had divergent traits. Closely related species had dissimilar abundances where they co-occurred, partially driven by trait dissimilarity, indicating character displacement. By integrating local-scale variation in primate community composition, evolutionary relatedness and functional diversity, this study found strong evidence that community assembly in this system can be explained by competition and character displacement along ecological gradients. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

  8. Bird fossils from Ankilitelo Cave: inference about Holocene environmental changes in southwestern Madagascar.

    PubMed

    Goodman, Steven M; Raherilalao, Marie Jeanne; Muldoon, Kathleen

    2013-12-23

    The identifications of non-permineralized fossil bird bones recovered from Ankilitelo Cave in southwestern Madagascar are presented. Among the more than 560 elements recovered, 29 different taxa were identified, the vast majority being species that still occur in this region of the island. Eggshell remains from the extinct elephant bird (Family Aepyornithidae) and assigned to Aepyornis sp. were found at the site. Two identified extant taxa, Scopus umbretta and Monias benschi, no longer occur in the area immediately surrounding the cave. The available radiocarbon measurements of collagen from fossil bird bones and avian eggshell carbonate of recovered from the cave range from 13,270 Cal yr BP to modern times. Hence, the presumed ecological shifts that took place resulting in the disappearance or range contractions of these three taxa is within the Holocene and are presumed to be associated with natural climatic change and in more recent centuries associated human pressures. Information is also presented on the origin of guinea fowl (Numida) and inference on the period of colonization of Corvus albus on Madagascar

  9. Widespread presence of the pathogenic fungus Batrachochytrium dendrobatidis in wild amphibian communities in Madagascar.

    PubMed

    Bletz, Molly C; Rosa, Gonçalo M; Andreone, Franco; Courtois, Elodie A; Schmeller, Dirk S; Rabibisoa, Nirhy H C; Rabemananjara, Falitiana C E; Raharivololoniaina, Liliane; Vences, Miguel; Weldon, Ché; Edmonds, Devin; Raxworthy, Christopher J; Harris, Reid N; Fisher, Matthew C; Crottini, Angelica

    2015-02-26

    Amphibian chytridiomycosis, an emerging infectious disease caused by the fungus Batrachochytrium dendrobatidis (Bd), has been a significant driver of amphibian declines. While globally widespread, Bd had not yet been reported from within Madagascar. We document surveys conducted across the country between 2005 and 2014, showing Bd's first record in 2010. Subsequently, Bd was detected in multiple areas, with prevalence reaching up to 100%. Detection of Bd appears to be associated with mid to high elevation sites and to have a seasonal pattern, with greater detectability during the dry season. Lineage-based PCR was performed on a subset of samples. While some did not amplify with any lineage probe, when a positive signal was observed, samples were most similar to the Global Panzootic Lineage (BdGPL). These results may suggest that Bd arrived recently, but do not exclude the existence of a previously undetected endemic Bd genotype. Representatives of all native anuran families have tested Bd-positive, and exposure trials confirm infection by Bd is possible. Bd's presence could pose significant threats to Madagascar's unique "megadiverse" amphibians.

  10. Multiple colonization of Madagascar and Socotra by colubrid snakes: evidence from nuclear and mitochondrial gene phylogenies.

    PubMed Central

    Nagy, Zoltán Tamás; Joger, Ulrich; Wink, Michael; Glaw, Frank; Vences, Miguel

    2003-01-01

    Colubrid snakes form a speciose group of unclarified phylogeny. Their almost cosmopolitan distribution could be interpreted as a product of plate-tectonic vicariance. We used sequences of the nuclear c-mos, the mitochondrial cytochrome b and the 16S rRNA genes in 41 taxa to elucidate the relationships between the endemic colubrid genera found in Madagascar and in the Socotra archipelago. The well-resolved trees indicate multiple origins of both the Malagasy and the Socotran taxa. The Malagasy genus Mimophis was nested within the Psammophiinae, and the Socotran Hemerophis was closely related to Old World representatives of the former genus Coluber. The remaining 14 genera of Malagasy colubrids formed a monophyletic sister group of the Socotran Ditypophis (together forming the Pseudoxyrhophiinae). Molecular-clock estimates place the divergence of Malagasy and Socotran colubrids from their non-insular sister groups into a time-frame between the Eocene and Miocene. Over-seas rafting is the most likely hypothesis for the origin of at least the Malagasy taxa. The discovery of a large monophyletic clade of colubrids endemic to Madagascar indicates a need for taxonomic changes. The relationship of this radiation to the Socotran Ditypophis highlights the potential of the Indian Ocean islands to act as an evolutionary reservoir for lineages that have become extinct in Africa and Asia. PMID:14728785

  11. Primates as Predictors of Mammal Community Diversity in the Forest Ecosystems of Madagascar.

    PubMed

    Muldoon, Kathleen M; Goodman, Steven M

    2015-01-01

    The geographic distribution of species is the typical metric for identifying priority areas for conservation. Since most biodiversity remains poorly studied, a subset of charismatic species, such as primates, often stand as surrogates for total biodiversity. A central question is therefore, how effectively do primates predict the pooled species richness of other mammalian taxa? We used lemurs as indicator species to predict total non-primate mammal community richness in the forest ecosystems of Madagascar. We combine environmental and species occurrence data to ascertain the extent to which primate diversity can predict (1) non-primate mammal α-diversity (species richness), (2) non-primate complementarity, and (3) non-primate β-diversity (species turnover). Our results indicate that primates are effective predictors of non-primate mammal community diversity in the forest ecosystems of Madagascar after controlling for habitat. When individual orders of mammals are considered, lemurs effectively predict the species richness of carnivorans and rodents (but not afrosoricids), complementarity of rodents (but not carnivorans or afrosoricids), and all individual components of β-diversity. We conclude that lemurs effectively predict total non-primate community richness. However, surrogate species alone cannot achieve complete representation of biodiversity.

  12. Evidence of prolonged torpor in Goodman's mouse lemurs at Ankafobe forest, central Madagascar.

    PubMed

    Blanco, Marina B; Andriantsalohimisantatra, Andon'ny A; Rivoharison, Tahiry V; Andriambeloson, Jean-Basile

    2017-01-01

    The small-bodied mouse lemurs of Madagascar (Microcebus) are capable of heterothermy (i.e., torpor or hibernation). The expression of these energy-saving strategies has been physiologically demonstrated in three species: M. berthae, the pygmy mouse lemur (daily torpor), M. murinus, the gray mouse lemur (daily torpor and hibernation), and M. griseorufus, the reddish-gray mouse lemur (daily, prolonged torpor and hibernation). Additional evidence, based on radiotracking and seasonal body mass changes, indicated that mouse lemur capabilities for heterothermy extended to M. lehilahytsara, the Goodman's mouse lemur. In this study, we confirm the use of hibernation in Goodman's mouse lemurs at a new location, a high-plateau forest fragment in Ankafobe, central Madagascar. Our evidence is based on sleeping site monitoring of radiocollared individuals and the retrieval of three mouse lemurs from inside a tree hole, all of which displayed a lethargic state. Though our data are preliminary and scant, we show that hibernation occurs in high-plateau mouse lemurs, and suggest that a buffered environment (i.e., tree holes instead of nests) may be crucial to avoiding potentially extreme ambient temperatures.

  13. Seroprevalence of hepatitis C and associated risk factors in urban areas of Antananarivo, Madagascar

    PubMed Central

    Ramarokoto, Charles E; Rakotomanana, Fanjasoa; Ratsitorahina, Maherisoa; Raharimanga, Vaomalala; Razafindratsimandresy, Richter; Randremanana, Rindra; Rakoto-Andrianarivelo, Mala; Rousset, Dominique; Andrianaja, Voahangy; Richard, Vincent; Soares, Jean-Louis; Rabarijaona, Leon P

    2008-01-01

    Background The risk factors for the transmission of HCV vary substantially between countries and geographic regions. The overall prevalence in south and east Africa region has been estimated to be 1.6% but limited information about the epidemiology of HCV infection in Madagascar is available Methods A cross-sectional survey for hepatitis C antibodies was conducted in 2,169 subjects of the general population of Antananarivo to determine seroprevalence of hepatitis C and associated risk factors. Results The overall seroprevalence was 1.2% (25/2,169). The prevalence did not differ significantly according to gender but it increased with age (Chi2 tendency test, p < 10-5). The variable history of hospitalization, previous therapeutic injections, dental treatment, intravenous drug use, and abnormal ALT and AST were statistically significantly related with the presence of HCV antibodies. No relationship with past history of blood transfusion was observed. Conclusion HCV prevalence in Madagascar seems to be similar to that in most other east African countries. Age appears to be an important risk factor. Iatrogenic causes of HCV transmission need to be further evaluated because all HCV cases had a history of receiving therapeutic injections and data suggested a cumulative effect in relation with therapeutic injections. PMID:18312652

  14. Outbreak of Tinea capitis and corporis in a primary school in Antananarivo, Madagascar.

    PubMed

    Carod, Jean-François; Ratsitorahina, Mahery; Raherimandimby, Hasina; Hincky Vitrat, Virginie; Ravaolimalala Andrianaja, Vololomboahangy; Contet-Audonneau, Nelly

    2011-10-13

    Tinea capitis is common among schoolchildren in developing countries but underreported in Madagascar. We report the occurrence of an outbreak of gray patch tinea capitis due to Microsporum langeronii in a public primary school of Antananarivo, the capital city of Madagascar. Forty-two children were included, 27 (64%) of them presenting with tinea capitis and 32 (76%) with Tinea corporis. Patients were treated with griseofulvin 500 mg and Povidone-iodine 4% and followed up for four weeks. Twenty-five (93%) of the 27 children with tinea capitis presented a gray patch as the main clinical feature. All these cases were fluorescent under Wood's UV light and positive in cultures for M. langeronii. All 27 children reported a contact with infected classmates, and 19 (70%) reported to have infected brothers and sisters at home. After four weeks of treatment, all patients recovered. Appropriate treatment and improved hygienic practices reduced the occurrence of tinea in the studied school and no more cases of tinea capitis or corporis occurred after the outbreak.

  15. Performance of a Receptive Language Test among Young Children in Madagascar

    PubMed Central

    Weber, Ann M.; Fernald, Lia C. H.; Galasso, Emanuela; Ratsifandrihamanana, Lisy

    2015-01-01

    Language tests developed and validated in one country may lose their desired properties when translated for use in another, possibly resulting in misleading estimates of ability. Using Item Response Theory (IRT) methodology, we assess the performance of a test of receptive vocabulary, the U.S.-validated Peabody Picture Vocabulary Test-Third Edition (PPVT-III), when translated, adapted, and administered to children 3 to 10 years of age in Madagascar (N = 1372), in the local language (Malagasy). Though Malagasy is considered a single language, there are numerous dialects spoken in Madagascar. Our findings were that test scores were positively correlated with age and indicators of socio-economic status. However, over half (57/96) of items evidenced unexpected response variation and/or bias by local dialect spoken. We also encountered measurement error and reduced differentiation among person abilities when we used the publishers’ recommended stopping rules, largely because we lost the original item ordering by difficulty when we translated test items into Malagasy. Our results suggest that bias and testing inefficiency introduced from the translation of the PPVT can be significantly reduced with the use of methods based on IRT at both the pre-testing and analysis stages. We explore and discuss implications for cross-cultural comparisons of internationally recognized tests, such as the PPVT. PMID:25830221

  16. The Paucity of Frugivores in Madagascar May Not Be Due to Unpredictable Temperatures or Fruit Resources

    PubMed Central

    Sinnott-Armstrong, Miranda; Baden, Andrea L.; Chapman, Colin A.; Daly, Douglas C.; Richard, Alison R.; Valenta, Kim; Donoghue, Michael J.

    2017-01-01

    The evolution of ecological idiosyncrasies in Madagascar has often been attributed to selective pressures stemming from extreme unpredictability in climate and resource availability compared to other tropical areas. With the exception of rainfall, few studies have investigated these assumptions. To assess the hypothesis that Madagascar’s paucity of frugivores is due to unreliability in fruiting resources, we use statistical modeling to analyze phenology datasets and their environmental correlates from two tropical wet forests, the Réserve Naturelle Intégrale Betampona in Madagascar, and Kibale National Park in Uganda. At each site we found that temperature is a good environmental predictor of fruit availability. We found no evidence of a significant difference in the predictability of fruit availability between the two sites, although the shorter duration of phenological monitoring at Betampona (two years, versus 15 years at Kibale) limits our ability to infer long-term patterns. Comparisons of long-term temperature data from each site (15 years from Kibale and 14 from Betampona) indicate that temperature is more predictable at Betampona than at Kibale. However, there does appear to be a difference between the two sites in the total fruit availability at any given time, with fruit being generally less abundant at Betampona. Our results appear contrary to the prevailing hypothesis of a selective force imposed by unpredictable resource availability or temperature, and we suggest other possible explanations for Madagascar’s unique biota. PMID:28085890

  17. Rural livelihoods and access to natural capital: Differences between migrants and non-migrants in Madagascar.

    PubMed

    Nawrotzki, Raphael J; Hunter, Lori M; Dickinson, Thomas W

    2012-06-27

    Although natural resources play a central role in rural livelihoods across the globe, little research has explored the relationship between migration and natural capital use, particularly in combination with other livelihood capitals (i.e., human, social, financial and physical). Grounded in the rural livelihood framework, this paper explores the association between the livelihood capital availability, especially natural capital, for migrants and non-migrants in rural Madagascar. Data from the 2008/2009 Demographic and Health Survey are used in combination with satellite imagery of vegetation coverage (Normalized Difference Vegetation Index, NDVI) to proxy natural resources. Hierarchical multilevel models allow for inclusion of cross-level interactions between migrant status and proximate natural resources as determinants of the status of livelihood assets. Three key findings emerge. First, higher levels of proximate natural resources are associated with greater financial, human, and social capital for both migrants and non-migrants. Second, migrants have, on average, greater financial, physical, human, and social capital than non-migrants, and urban-to-rural migrants do exceptionally well on all capital asset categories. Third, migrants residing in areas with higher levels of natural capital tend to have significantly higher levels of human capital (education). Although we cannot examine livelihood strategies per se, the results suggest variation in livelihood potential among migrants and non-migrants in rural Madagascar, with migrants tending to have greater capital assets. In addition, access to natural resources is a central livelihood strategy.

  18. Mantle upwelling beneath Madagascar: evidence from receiver function analysis and shear wave splitting

    NASA Astrophysics Data System (ADS)

    Paul, Jonathan D.; Eakin, Caroline M.

    2017-07-01

    Crustal receiver functions have been calculated from 128 events for two three-component broadband seismomenters located on the south coast (FOMA) and in the central High Plateaux (ABPO) of Madagascar. For each station, crustal thickness and V p / V s ratio were estimated from H- κ plots. Self-consistent receiver functions from a smaller back-azimuthal range were then selected, stacked and inverted to determine shear wave velocity structure as a function of depth. These results were corroborated by guided forward modeling and by Monte Carlo error analysis. The crust is found to be thinner (39 ± 0.7 km) beneath the highland center of Madagascar compared to the coast (44 ± 1.6 km), which is the opposite of what would be expected for crustal isostasy, suggesting that present-day long wavelength topography is maintained, at least in part, dynamically. This inference of dynamic support is corroborated by shear wave splitting analyses at the same stations, which produce an overwhelming majority of null results (>96 %), as expected for vertical mantle flow or asthenospheric upwelling beneath the island. These findings suggest a sub-plate origin for dynamic support.

  19. The role of demography and markets in determining deforestation rates near Ranomafana National Park, Madagascar.

    PubMed

    Brooks, Christopher P; Holmes, Christopher; Kramer, Karen; Barnett, Barry; Keitt, Timothy H

    2009-06-17

    The highland forests of Madagascar are home to some of the world's most unique and diverse flora and fauna and to some of its poorest people. This juxtaposition of poverty and biodiversity is continually reinforced by rapid population growth, which results in increasing pressure on the remaining forest habitat in the highland region, and the biodiversity therein. Here we derive a mathematical expression for the subsistence of households to assess the role of markets and household demography on deforestation near Ranomafana National Park. In villages closest to urban rice markets, households were likely to clear less land than our model predicted, presumably because they were purchasing food at market. This effect was offset by the large number of migrant households who cleared significantly more land between 1989-2003 than did residents throughout the region. Deforestation by migrant households typically occurred after a mean time lag of 9 years. Analyses suggest that while local conservation efforts in Madagascar have been successful at reducing the footprint of individual households, large-scale conservation must rely on policies that can reduce the establishment of new households in remaining forested areas.

  20. Statut familial et inégalités face à la scolarisation à Madagascar

    NASA Astrophysics Data System (ADS)

    Delaunay, Valérie; Gastineau, Bénédicte; Andriamaro, Frédérique

    2013-12-01

    The impact of family status in Madagascar on inequalities in schooling - In this article, in the context of generalised access to primary education and parity between girls and boys, we analyse data from the Demographic and Health Survey (DHS) 2009 in Madagascar to examine inequalities in schooling related to children's status in the family. The results confirm the protective benefit for children of living with their biological parents. Fostered children are disadvantaged, especially and increasingly so depending on whether they live with an uncle or aunt, with a distant relative or a non-relative. Conversely, children who reside in the home of a brother or sister are not disadvantaged, a result which reflects the role of elder children in family education strategies. Grandparents play a moderately positive role in schooling. The death of the father is an important factor in dropping out. Finally, children whose parent or parents are not household heads are disadvantaged in terms of schooling compared to children of household heads.

  1. Interannual variability of South Equatorial Current bifurcation and western boundary currents along the Madagascar coast

    NASA Astrophysics Data System (ADS)

    Yamagami, Y.; Tozuka, T.

    2015-12-01

    The South Equatorial Current (SEC) in the southern Indian Ocean bifurcates at the east coast of Madagascar into the Northeast and Southeast Madagascar Currents (NEMC and SEMC, respectively). In observational and reanalysis data, interannual variations of the NEMC and SEMC transports are strongly correlated with those of the SEC transport, rather than those of the SEC bifurcation latitude (SBL). Their dynamical mechanisms are then examined based on the Time-Dependent Island Rule for the first time. It is shown that interannual anomalies of the SBL as well as the NEMC and SEMC transports are predominantly a response to the anomalous inflow from the ocean interior that is determined by the meridional interior transport. This, in turn, is a result of westward propagating Rossby waves induced by wind stress curl anomalies mainly in 60°E-90°E. The above mechanism is contrasted with that of the seasonal variation, where the local transport driven by wind stress around the island plays a role. Furthermore, the interannual variations of the SBL and the NEMC and SEMC transports are significantly correlated with the Niño 3.4 index with 5-15 months lag. It is suggested that diabatic heating anomalies associated with the El Niño/Southern Oscillation (ENSO) along with a local process in the southeastern Indian Ocean may generate wind stress curl anomalies over the southern Indian Ocean.

  2. Mantle upwelling beneath Madagascar: evidence from receiver function analysis and shear wave splitting

    NASA Astrophysics Data System (ADS)

    Paul, Jonathan D.; Eakin, Caroline M.

    2017-01-01

    Crustal receiver functions have been calculated from 128 events for two three-component broadband seismomenters located on the south coast (FOMA) and in the central High Plateaux (ABPO) of Madagascar. For each station, crustal thickness and V p /V s ratio were estimated from H- κ plots. Self-consistent receiver functions from a smaller back-azimuthal range were then selected, stacked and inverted to determine shear wave velocity structure as a function of depth. These results were corroborated by guided forward modeling and by Monte Carlo error analysis. The crust is found to be thinner (39 ± 0.7 km) beneath the highland center of Madagascar compared to the coast (44 ± 1.6 km), which is the opposite of what would be expected for crustal isostasy, suggesting that present-day long wavelength topography is maintained, at least in part, dynamically. This inference of dynamic support is corroborated by shear wave splitting analyses at the same stations, which produce an overwhelming majority of null results (>96 %), as expected for vertical mantle flow or asthenospheric upwelling beneath the island. These findings suggest a sub-plate origin for dynamic support.

  3. Prevalence and correlates of tobacco use among school-going adolescents in Madagascar.

    PubMed

    Veeranki, Sreenivas P; Mamudu, Hadii M; John, Rijo M; Ouma, Ahmed E O

    2015-09-01

    Approximately 90% of adults start smoking during adolescence, with limited studies conducted in low-and-middle-income countries where over 80% of global tobacco users reside. The study aims to estimate prevalence and identify predictors associated with adolescents' tobacco use in Madagascar. We utilized tobacco-related information of 1184 school-going adolescents aged 13-15 years, representing a total of 296,111 youth from the 2008 Madagascar Global Youth Tobacco Survey to determine the prevalence of tobacco use. Gender-wise multivariable logistic regression models were conducted to identify key predictors. Approximately 19% (30.7% males; 10.2% females) of adolescents currently smoke cigarettes, and 7% (8.5% males and 5.8% females) currently use non-cigarette tobacco products. Regardless of sex, peer smoking behavior was significantly associated with increased tobacco use among adolescents. In addition, exposures to tobacco industry promotions, secondhand smoke (SHS) and anti-smoking media messages were associated with tobacco use. The strong gender gap in the use of non-cigarette tobacco products, and the role of peer smoking and industry promotions in adolescent females' tobacco use should be of major advocacy and policy concern. A comprehensive tobacco control program integrating parental and peer education, creating social norms, and ban on promotions is necessary to reduce adolescents' tobacco use.

  4. The settlement of Madagascar: what dialects and languages can tell us.

    PubMed

    Serva, Maurizio

    2012-01-01

    The dialects of Madagascar belong to the Greater Barito East group of the Austronesian family and it is widely accepted that the Island was colonized by Indonesian sailors after a maritime trek that probably took place around 650 CE. The language most closely related to Malagasy dialects is Maanyan, but Malay is also strongly related especially for navigation terms. Since the Maanyan Dayaks live along the Barito river in Kalimantan (Borneo) and they do not possess the necessary skill for long maritime navigation, they were probably brought as subordinates by Malay sailors. In a recent paper we compared 23 different Malagasy dialects in order to determine the time and the landing area of the first colonization. In this research we use new data and new methods to confirm that the landing took place on the south-east coast of the Island. Furthermore, we are able to state here that colonization probably consisted of a single founding event rather than multiple settlements. To reach our goal we find out the internal kinship relations among all the 23 Malagasy dialects and we also find out the relations of the 23 dialects to Malay and Maanyan. The method used is an automated version of the lexicostatistic approach. The data from Madagascar were collected by the author at the beginning of 2010 and consist of Swadesh lists of 200 items for 23 dialects covering all areas of the Island. The lists for Maanyan and Malay were obtained from a published dataset integrated with the author's interviews.

  5. Well-Being Is a Process of Becoming: Respondent-Led Research with Organic Farmers in Madagascar

    ERIC Educational Resources Information Center

    Farnworth, Cathy Rozel

    2009-01-01

    Malagasy "players"--farmers, middle men, organic organisations and policy makers--see in export-orientated organic agriculture a way for Madagascar to build upon its historic export strengths: spices, essential oils, medicinal plants and tropical fruits. They point to the "de facto" organic status of most farming in the country…

  6. The biogeographic origin of a radiation of trees in Madagascar: implications for the assembly of a tropical forest biome.

    PubMed

    Federman, Sarah; Dornburg, Alex; Downie, Alexander; Richard, Alison F; Daly, Douglas C; Donoghue, Michael J

    2015-10-05

    Madagascar's rain forests are characterized by extreme and uneven patterns of species richness and endemicity, the biogeographic and evolutionary origins of which are poorly understood. Here we use a time-calibrated phylogeny of a dominant group of trees in Madagascar's eastern rain forests, Canarium, and related Burseraceae (Canarieae), to test biogeographic hypotheses regarding the origin and radiation of the flora of this unique biome. Our findings strongly support the monophyly of Malagasy Canarium, suggesting that this clade represents a previously undocumented in situ radiation. Contrary to expectations of dispersal from Africa during the Oligocene, concurrent with the formation of Madagascar's rain forest biome, our analyses support a late Miocene origin for Malagasy Canarium, probably by long distance dispersal from Southeast Asia. Our study illustrates the importance of considering long distance dispersal as a viable explanation for clades with pantropical distributions diversifying subsequent to the Oligocene, and it highlights the formation of the Indo-Australian Archipelago and associated fast-moving equatorial surface currents, suggesting an under-appreciated evolutionary link among tropical centers of endemism. We postulate that the relatively recent establishment and radiation of Canarium in Madagascar may have been facilitated by the highly stochastic climates associated with these forest ecosystems.

  7. A new species of Diastatotropis Lacordaire (Coleoptera: Anthribidae) from Montagne d'Ambre National Park, northern Madagascar.

    PubMed

    Trýzna, Miloš; Baňař, Petr

    2017-01-20

    A new species, Diastatotropis perrinae Trýzna & Baňař sp. nov. (Anthribidae: Anthribinae: Cappadocini), from north Madagascar is described. Male genitalia are studied and illustrated and colour photographs are added. A comparison with the most similar known species, D. tigrinus Lacordaire, 1866, is provided.

  8. Well-Being Is a Process of Becoming: Respondent-Led Research with Organic Farmers in Madagascar

    ERIC Educational Resources Information Center

    Farnworth, Cathy Rozel

    2009-01-01

    Malagasy "players"--farmers, middle men, organic organisations and policy makers--see in export-orientated organic agriculture a way for Madagascar to build upon its historic export strengths: spices, essential oils, medicinal plants and tropical fruits. They point to the "de facto" organic status of most farming in the country…

  9. Setting Up a Bibliographic Database from National Inventory of Scientific and Technical Literature. The CIDST Experience in Madagascar.

    ERIC Educational Resources Information Center

    Andriamparany, Louis Marius; And Others

    1991-01-01

    Describes the development of a bibliographic database in Madagascar through a national inventory of scientific and technical literature. The roles of the Ministry of Scientific and Technological Research for Development (MRSTD) and its information service, CIDST, are described; database products are discussed; and future prospects are suggested.…

  10. In or Out-of-Madagascar?—Colonization Patterns for Large-Bodied Diving Beetles (Coleoptera: Dytiscidae)

    PubMed Central

    Bukontaite, Rasa; Ranarilalatiana, Tolotra; Randriamihaja, Jacquelin Herisahala; Bergsten, Johannes

    2015-01-01

    High species diversity and endemism within Madagascar is mainly the result of species radiations following colonization from nearby continents or islands. Most of the endemic taxa are thought to be descendants of a single or small number of colonizers that arrived from Africa sometime during the Cenozoic and gave rise to highly diverse groups. This pattern is largely based on vertebrates and a small number of invertebrate groups. Knowledge of the evolutionary history of aquatic beetles on Madagascar is lacking, even though this species-rich group is often a dominant part of invertebrate freshwater communities in both standing and running water. Here we focus on large bodied diving beetles of the tribes Hydaticini and Cybistrini. Our aims with this study were to answer the following questions 1) How many colonization events does the present Malagasy fauna originate from? 2) Did any colonization event lead to a species radiation? 3) Where did the colonizers come from—Africa or Asia—and has there been any out-of-Madagascar event? 4) When did these events occur and were they concentrated to any particular time interval? Our results suggest that neither in Hydaticini nor in Cybistrini was there a single case of two or more endemic species forming a monophyletic group. The biogeographical analysis indicated different colonization histories for the two tribes. Cybistrini required at least eight separate colonization events, including the non-endemic species, all comparatively recent except the only lotic (running water) living Cybister operosus with an inferred colonization at 29 Ma. In Hydaticini the Madagascan endemics were spread out across the tree, often occupying basal positions in different species groups. The biogeographical analyses therefore postulated the very bold hypothesis of a Madagascan origin at a very deep basal node within Hydaticus and multiple out-of-Madagascar dispersal events. This hypothesis needs to be tested with equally intense taxon

  11. In and out of Madagascar: Dispersal to Peripheral Islands, Insular Speciation and Diversification of Indian Ocean Daisy Trees (Psiadia, Asteraceae)

    PubMed Central

    Strijk, Joeri S.; Noyes, Richard D.; Strasberg, Dominique; Cruaud, Corinne; Gavory, Fredéric; Chase, Mark W.; Abbott, Richard J.; Thébaud, Christophe

    2012-01-01

    Madagascar is surrounded by archipelagos varying widely in origin, age and structure. Although small and geologically young, these archipelagos have accumulated disproportionate numbers of unique lineages in comparison to Madagascar, highlighting the role of waif-dispersal and rapid in situ diversification processes in generating endemic biodiversity. We reconstruct the evolutionary and biogeographical history of the genus Psiadia (Asteraceae), a plant genus with near equal numbers of species in Madagascar and surrounding islands. Analyzing patterns and processes of diversification, we explain species accumulation on peripheral islands and aim to offer new insights on the origin and potential causes for diversification in the Madagascar and Indian Ocean Islands biodiversity hotspot. Our results provide support for an African origin of the group, with strong support for non-monophyly. Colonization of the Mascarenes took place by two evolutionary distinct lineages from Madagascar, via two independent dispersal events, each unique for their spatial and temporal properties. Significant shifts in diversification rate followed regional expansion, resulting in co-occurring and phenotypically convergent species on high-elevation volcanic slopes. Like other endemic island lineages, Psiadia have been highly successful in dispersing to and radiating on isolated oceanic islands, typified by high habitat diversity and dynamic ecosystems fuelled by continued geological activity. Results stress the important biogeographical role for Rodrigues in serving as an outlying stepping stone from which regional colonization took place. We discuss how isolated volcanic islands contribute to regional diversity by generating substantial numbers of endemic species on short temporal scales. Factors pertaining to the mode and tempo of archipelago formation and its geographical isolation strongly govern evolutionary pathways available for species diversification, and the potential for successful

  12. In vitro activities of 18 antimicrobial agents against Staphylococcus aureus isolates from the Institut Pasteur of Madagascar

    PubMed Central

    Randrianirina, Frédérique; Soares, Jean-Louis; Ratsima, Elisoa; Carod, Jean-François; Combe, Patrice; Grosjean, Pierre; Richard, Vincent; Talarmin, Antoine

    2007-01-01

    Background Staphylococcus aureus, one of the most frequently isolated pathogens in both hospitals and the community, has been particularly efficient at developing resistance to antimicrobial agents. In developed countries, as methicillin-resistant S. aureus (MRSA) has prevailed and, furthermore, as S. aureus with reduced susceptibility to vancomycin has emerged, the therapeutic options for the treatment of S. aureus infections have become limited. In developing countries and especially African countries very little is known concerning the resistance of S. aureus to antibiotics. In Madagascar no data exist concerning this resistance. Objective To update the current status of antibiotic resistance of S. aureus in Antananarivo, Madagascar. Methods Clinical S. aureus isolates were collected from patients at the Institut Pasteur of Madagascar from January 2001 to December 2005. Susceptibility tests with 18 antibiotics were performed by the disk diffusion method. Results Among a total of 574 isolates, 506 were from community-acquired infections and 68 from nosocomial infections. There was no significant difference in the methicillin resistance rate between community-acquired strains (33 of 506; 6.5%) and nosocomial strains (3 of 68, 4.4%). Many MRSA isolates were resistant to multiple classes of antibiotics. Resistance to tetracyclin, trimethoprim-sulfamethoxazole and erythromycin was more common. Among MRSA isolates resistance rates to rifampicin, fusidic acid, gentamicin and ciprofloxacin were lower than that observed with other drugs easily available in Madagascar. No isolates were resistant to glycopeptides. Conclusion The rate of methicillin-resistant S. aureus is not different between community-acquired and nosocomial infections and is still rather low in Madagascar. PMID:17521424

  13. Epidemiological and virological characterization of 2009 pandemic influenza A virus subtype H1N1 in Madagascar.

    PubMed

    Orelle, Arnaud; Razanajatovo, Norosoa Harline; Rajatonirina, Soatiana; Hoffmann, Jonathan; Randrianasolo, Laurence; Razafitrimo, Girard Marcellin; Naidoo, Dhamari; Richard, Vincent; Heraud, Jean-Michel

    2012-12-15

    Madagascar was one of the first African countries to be affected by the 2009 pandemic of influenza A virus subtype H1N1 [A(H1N1)pdm2009] infection. The outbreak started in the capital city, Antananarivo, and then spread throughout the country from October 2009 through February 2010. Specimens from patients presenting with influenza-like illness were collected and shipped to the National Influenza Center in Madagascar for analyses, together with forms containing patient demographic and clinical information. Of the 2303 specimens tested, 1016 (44.1%) and 131 (5.7%) yielded A(H1N1)pdm09 and seasonal influenza virus, respectively. Most specimens (42.0%) received were collected from patients <10 years old. Patients <20 years old were more likely than patients >50 years old to be infected with A(H1N1)pdm09 (odds ratio, 2.1; 95% confidence interval, 1.7-2.6; P < .01). Although phylogenetic analyses of A(H1N1)pdm09 suggested multiple introductions of the virus into Madagascar, no antigenic differences between A(H1N1)pdm09 viruses recovered in Madagascar and those that circulated worldwide were observed. The high proportion of respiratory specimens positive for A(H1N1)pdm09 is consistent with a widespread transmission of the pandemic in Madagascar. The age distribution of cases of A(H1N1)pdm09 infection suggests that children and young adults could be targeted for interventions that aim to reduce transmission during an influenza pandemic.

  14. Lithosphere structure in southern Madagascar from receiver function and ambient noise correlation: implication for the crustal evolution

    NASA Astrophysics Data System (ADS)

    Rindraharisaona, Elisa J.; Tilmann, Frederik; Yuan, Xiaohui; Rümpker, Georg; Reiss, Miriam

    2016-04-01

    Madagascar was part of Gondwanaland, sandwiched between India and Africa. The assembly during the Pan-African orogeny has left its mark on the Malagasy basement in the form of metamorphic and mineral belts and shear zones, which occupy the eastern two third of Madagascar. The western third is characterized by Triassic to Jurassic sedimentary basin formation. The main objective of our work is to determine to which extent the recent episodes and shear zones reactivation have modified the lithosphere structure in southern Madagascar. The data used come from a temporary seismic array operated in southern Madagascar between 2011 and 2014 and two permanent stations in the study areas. We investigated the lithosphere structure in southern Madagascar by analyzing receiver functions with the H-k stacking and common conversion point stacking methods; extracting the Rayleigh wave group velocities from the ambient noise; and jointly inverting the receiver functions and Rayleigh wave dispersion curves. Results show that (1) The sedimentary thickness changes from 10 km (West) to 3 km (East) in the Morondava basin, where the crust is thin (between 23 and 30 km) and vp/vs ratio is relatively high (from 1.73 to 1.85); (2)In the Proterozoic terrane, the Moho depth ranges from 33 to 38 km and vp/vs ratio varies between 1.72 and 1.82; (3) The Archean basement has a thick crust (between 38 and 43 km) and a low vp/vs ratio (1.67-1.77); (4) A mafic lower crust (vs>3.9 km/s) of 2-22 km thick is observed in the Archean basements. Our interpretation is that the shear zone reactivation after the separation combined with the crustal extension has delaminated the mafic lower crust in the Proterozoic crust and resulted in the current felsic-to-intermediate lower crustal type; and the Archean crust appears to be largely unmodified by Cenozoic tectonism.

  15. Endemism and diversification in freshwater insects of Madagascar revealed by coalescent and phylogenetic analysis of museum and field collections.

    PubMed

    Vuataz, Laurent; Sartori, Michel; Gattolliat, Jean-Luc; Monaghan, Michael T

    2013-03-01

    The biodiversity and endemism of Madagascar are among the most extraordinary and endangered in the world. This includes the island's freshwater biodiversity, although detailed knowledge of the diversity, endemism, and biogeographic origin of freshwater invertebrates is lacking. The aquatic immature stages of mayflies (Ephemeroptera) are widely used as bio-indicators and form an important component of Malagasy freshwater biodiversity. Many species are thought to be microendemics, restricted to single river basins in forested areas, making them particularly sensitive to habitat reduction and degradation. The Heptageniidae are a globally diverse family of mayflies (>500 species) but remain practically unknown in Madagascar except for two species described in 1996. The standard approach to understanding their diversity, endemism, and origin would require extensive field sampling on several continents and years of taxonomic work followed by phylogenetic analysis. Here we circumvent this using museum collections and freshly collected individuals in a combined approach of DNA taxonomy and phylogeny. The coalescent-based GMYC analysis of DNA barcode data (mitochondrial COI) revealed 14 putative species on Madagascar, 70% of which were microendemics. A phylogenetic analysis that included African and Asian species and data from two mitochondrial and four nuclear loci indicated the Malagasy Heptageniidae are monophyletic and sister to African species. The genus Compsoneuria is shown to be paraphyletic and the genus Notonurus is reinstalled for African and Malagasy species previously placed in Compsoneuria. A molecular clock excluded a Gondwanan vicariance origin and instead favoured a more recent overseas colonization of Madagascar. The observed monophyly and high microendemism highlight their conservation importance and suggest the DNA-based approach can rapidly provide information on the diversity, endemism, and origin of freshwater biodiversity. Our results underline the

  16. A new species of Rhabdias Stiles et Hassall, 1905 (Nematoda: Rhabdiasidae) from Blommersia domerguei (Guibé) (Amphibia: Mantellidae) in Madagascar.

    PubMed

    Kuzmin, Yuriy; Junker, Kerstin; du Preez, Louis; Bain, Odile

    2013-11-01

    Rhabdias blommersiae sp. n. (Nematoda: Rhabdiasidae) is described from the lungs of Domergue's Madagascar frog, Blommersia domerguei (Guibé) (Amphibia: Mantellidae), in Madagascar. The new species differs from congeners parasitizing amphibians in having a smaller body and buccal capsule, six equal lips, large excretory glands of unequal length and a posteriorly inflated body vesicle. A combination of characters distinguishes it from Afromalagasy species of Rhabdias Stiles et Hassall, 1905. Rhabdias blommersiae is the third species of the genus described from amphibians in Madagascar. Close similarities in the number and shape of circumoral structures in two Rhabdias species described from mantellid hosts in Madagascar suggest a close relationship and common origin of the two species, with subsequent adaptation to separate hosts within the Mantellidae.

  17. Baseline population health conditions ahead of a health system strengthening program in rural Madagascar

    PubMed Central

    Miller, Ann C.; Ramananjato, Ranto H.; Garchitorena, Andres; Rabeza, Victor R.; Gikic, Djordje; Cripps, Amber; Cordier, Laura; Rahaniraka Razanadrakato, Hery-Tiana; Randriamanambintsoa, Marius; Hall, Lara; Murray, Megan; Safara Razanavololo, Felicite; Rich, Michael L.; Bonds, Matthew H.

    2017-01-01

    ABSTRACT Background: A model health district was initiated through a program of health system strengthening (HSS) in Ifanadiana District of southeastern Madagascar in 2014. We report population health indicators prior to initiation of the program. Methods: A representative household survey based on the Demographic Health Survey was conducted using a two-stage cluster sampling design in two strata – the initial program catchment area and the future catchment area. Chi-squared and t-tests were used to compare data by stratum, using appropriate sampling weights. Madagascar data for comparison were taken from a 2013 national study. Results: 1522 households were surveyed, representing 8310 individuals including 1635 women ages 15–49, 1685 men ages 15–59 and 1251 children under age 5. Maternal mortality rates in the district are 1044/100,000. 81% of women’s last childbirth deliveries were in the home; only 20% of deliveries were attended by a doctor or nurse/midwife (not different by stratum). 9.3% of women had their first birth by age 15, and 29.5% by age 18. Under-5 mortality rate is high: 145/1000 live births vs. 62/1000 nationally. 34.6% of children received all recommended vaccines by age 12 months (compared to 51.5% in Madagascar overall). In the 2 weeks prior to interview, approximately 28% of children under age 5 had acute respiratory infections of whom 34.7% were taken for care, and 14% of children had diarrhea of whom 56.6% were taken for care. Under-5 mortality, illness, care-seeking and vaccination rates were not significantly different between strata. Conclusions: Indicators of population health and health care-seeking reveal low use of the formal health system, which could benefit from HSS. Data from this survey and from a longitudinal follow-up study will be used to target needed interventions, to assess change in the district and the impact of HSS on individual households and the population of the district. PMID:28621206

  18. Baseline population health conditions ahead of a health system strengthening program in rural Madagascar.

    PubMed

    Miller, Ann C; Ramananjato, Ranto H; Garchitorena, Andres; Rabeza, Victor R; Gikic, Djordje; Cripps, Amber; Cordier, Laura; Rahaniraka Razanadrakato, Hery-Tiana; Randriamanambintsoa, Marius; Hall, Lara; Murray, Megan; Safara Razanavololo, Felicite; Rich, Michael L; Bonds, Matthew H

    2017-01-01

    A model health district was initiated through a program of health system strengthening (HSS) in Ifanadiana District of southeastern Madagascar in 2014. We report population health indicators prior to initiation of the program. A representative household survey based on the Demographic Health Survey was conducted using a two-stage cluster sampling design in two strata - the initial program catchment area and the future catchment area. Chi-squared and t-tests were used to compare data by stratum, using appropriate sampling weights. Madagascar data for comparison were taken from a 2013 national study. 1522 households were surveyed, representing 8310 individuals including 1635 women ages 15-49, 1685 men ages 15-59 and 1251 children under age 5. Maternal mortality rates in the district are 1044/100,000. 81% of women's last childbirth deliveries were in the home; only 20% of deliveries were attended by a doctor or nurse/midwife (not different by stratum). 9.3% of women had their first birth by age 15, and 29.5% by age 18. Under-5 mortality rate is high: 145/1000 live births vs. 62/1000 nationally. 34.6% of children received all recommended vaccines by age 12 months (compared to 51.5% in Madagascar overall). In the 2 weeks prior to interview, approximately 28% of children under age 5 had acute respiratory infections of whom 34.7% were taken for care, and 14% of children had diarrhea of whom 56.6% were taken for care. Under-5 mortality, illness, care-seeking and vaccination rates were not significantly different between strata. Indicators of population health and health care-seeking reveal low use of the formal health system, which could benefit from HSS. Data from this survey and from a longitudinal follow-up study will be used to target needed interventions, to assess change in the district and the impact of HSS on individual households and the population of the district.

  19. Multiple causes of an unexpected malaria outbreak in a high-transmission area in Madagascar.

    PubMed

    Kesteman, Thomas; Rafalimanantsoa, Solofoniaina A; Razafimandimby, Harimahefa; Rasamimanana, Heriniaina H; Raharimanga, Vaomalala; Ramarosandratana, Benjamin; Ratsimbasoa, Arsene; Ratovonjato, Jocelyn; Elissa, Nohal; Randrianasolo, Laurence; Finlay, Alyssa; Rogier, Christophe; Randrianarivelojosia, Milijaona

    2016-02-02

    The malaria burden in Madagascar dropped down last decade, largely due to scale-up of control measures. Nevertheless, a significant rise of malaria cases occurred in 2011-2012 in two regions of the rainy South-Eastern Madagascar, where malaria is considered as mesoendemic and the population is supposed to be protected by its acquired immunity against Plasmodium. A multidisciplinary investigation was conducted in order to identify the causes of the outbreak. In March 2012, a cross-sectional study was conducted in 20 randomly selected clusters, involving the rapid diagnostic testing of all ≥6 month-old members of households and a questionnaire about socio-demographic data and exposure to malaria control interventions. Changes in environmental conditions were evaluated by qualitative interview of local authorities, climatic conditions were evaluated by remote-sensing, and stock outs of malaria supplies in health facilities were evaluated by quantitative means. Two long-lasting insecticidal nets (LLINs) were sampled in each cluster in order to evaluate their condition and the remanence of their insecticidal activity. The entomological investigation also encompassed the collection Anopheles vectors in two sites, and the measure of their sensitivity to deltamethrin. The cross-sectional survey included 1615 members of 440 households. The mean Plasmodium infection rate was 25.6 % and the mean bed net use on the day before survey was 71.1 %. The prevalence of Plasmodium infections was higher in 6-14 year-old children (odds ratio (OR) 7.73 [95 % CI 3.58-16.68]), in rural areas (OR 6.25 [4.46-8.76]), in poorest socio-economic tercile (OR 1.54 [1.13-2.08]), and it was lower in individuals sleeping regularly under the bed net (OR 0.51 [0.32-0.82]). Stock outs of anti-malarial drugs in the last 6 months have been reported in two third of health facilities. Rainfalls were increased as compared with the three previous rainy seasons. Vectors collected were sensitive to

  20. Cover sequences at the northern margin of the Antongil Craton, NE Madagascar

    USGS Publications Warehouse

    Bauer, W.; Walsh, G.J.; De Waele, B.; Thomas, Ronald J.; Horstwood, M.S.A.; Bracciali, L.; Schofield, D.I.; Wollenberg, U.; Lidke, D.J.; Rasaona, I.T.; Rabarimanana, M.H.

    2011-01-01

    The island of Madagascar is a collage of Precambrian, generally high-grade metamorphic basement domains, that are locally overlain by unmetamorphosed sedimentary rocks and poorly understood low-grade metasediments. In the Antalaha area of NE Madagascar, two distinct cover sequences rest on high-grade metamorphic and igneous basement rocks of the Archaean Antongil craton and the Neoproterozoic Bemarivo belt. The older of these two cover sequences, the Andrarona Group, consists of low-grade metasedimentary rocks. The younger sequence, the newly defined Ampohafana Formation, consists of unmetamorphosed sedimentary rocks. The Andrarona Group rests on Neoarchaean granites and monzogranites of the Antongil craton and consists of a basal metagreywacke, thick quartzites and an upper sequence of sericite-chlorite meta-mudstones, meta-sandstones and a volcaniclastic meta-sandstone. The depositional age of the volcaniclastic meta-sandstone is constrained in age by U–Pb laser-ablation ICP-MS analyses of euhedral zircons to 1875 ± 8 Ma (2σ). Detrital zircons of Archaean and Palaeoproterozoic age represent an input from the Antongil craton and a newly defined Palaeoproterozoic igneous unit, the Masindray tonalite, which underlies the Andrarona Group, and yielded a U–Pb zircon age of 2355 ± 11 Ma (2σ), thus constraining the maximum age of deposition of the basal part of the Andrarona Group. The Andrarona Group shows a low-grade metamorphic overprint in the area near Antalaha; illite crystallinity values scatter around 0.17°Δ2Θ CuKα, which is within the epizone. The Ampohafana Formation consists of undeformed, polymict conglomerate, cross-bedded sandstone, and red mudstone. An illite crystallinity value of >0.25°Δ2Θ CuKα obtained from the rocks is typical of the diagenetic zone. Occurrences of rhyodacite pebbles in the Ampohafana Formation and the intrusion of a basaltic dyke suggest a deposition in a WSW-ENE-trending graben system during the opening of the Indian

  1. Recent structural and geochronological data on central Madagascar: in search of the earliest Panafrican events

    NASA Astrophysics Data System (ADS)

    Nédélec, A.; Paquette, J. L.; Ralison, B.; Bouchez, J. L.; Grégoire, V.

    2003-04-01

    The basement of central Madagascar registered a polyphase history during Panafrican times. The latest events (560--530 Ma) are responsible for a major N-S shear zone, the Angavo shear zone, characterized by steep foliation planes and N-S subhorizontal lineations (Nédélec et al., 2000). This shear zone has been active in low-pressure granulitic conditions and favoured the emplacement of shoshonitic magmas (e.g. Carion pluton). Due to its length and width (respectively 600 and 20 km), it is likely a structure of lithospheric significance. It is due to intracratonic reworking related to the final stages of Gondwana amalgamation. To the east, Collins &Windley (2002) suggest the existence of a suture (Betsimisaraka suture) along the Archaean Antongil block. However, the age of this suture and the existence of oceanic remnants are still to be unraveled, a point of major importance in the understanding of the Panafrcian collision. To the west, differents units have been recognized. The Itremo Series is the uppermost unit. As such, it is less metamorphosed and keeps evidence of early events. It is made of supracrustal rocks, the so-called SQC (schist-quartzite-carbonate) series, typical of a passive margin sequence. Microstructures and quartz c-axis fabrics in the quartzites bear evidence of an east-directed ductile shearing event (Nédélec et al., 2003), whose age is still unknown. Gneisses and migmatites underlying the Itremo sheet belong to the Graphite System, which also contain abundant intrusives. Calk-alkaline orthogneisses about 780 Ma are regarded as former arc magmas predating the Panafrican collision (Handke et al., 1999). Alkaline "stratoid" (sill-like) granites and syenites were dated at 630 Ma by Paquette &Nédélec (1998). A new U-Pb zircon age of 717 Ma from a Midongy-type (pink, fine-grained, biotite-bearing, mildly peraluminous) stratoid granite, west of the Itremo series, may represent the earliest event due to the Panafrican orogeny in Madagascar

  2. REE concentration processes in ion adsorption deposits: Evidence from Madagascar and China.

    NASA Astrophysics Data System (ADS)

    Smith, Martin; Estrade, Guillaume; Marquis, Eva; Goodenough, Kathryn; Nasun, Peter; Cheng, Xu; Kynicky, Jindrich

    2017-04-01

    Lateritic clay deposits, where the rare earth elements (REE) occur adsorbed to clay mineral surfaces, are the world's dominant supply of heavy REE (Gd-Lu). These deposits are currently only mined in China where there is a reported heavy REE enrichment, but other deposits are currently under exploration in Brazil, the Philippines and Madagascar. Concentration of REE within IADs has been proposed to be a dominantly supergene process, where easily degradable REE-minerals (e.g. REE-fluorcarbonates) break down and release REE that are then adsorbed to clay minerals resulting in HREE enrichment. Here we present data from the Ambohimirahavavy Complex, Madagascar, and compare them to data from mineralised profiles in China, with the aim of further constraining the formation and REE enrichment processes in ion adsorption deposits. Bulk rock total REE contents from Madagascar vary from 400-5000ppm, with the HREE varying from 10 to 20% of the TREE. Ammonium Sulphate leaches (designed to remove clay-adsorbed REE) of laterite show leachable TREE from 130-500ppm, with no preferential HREE adsorption. Within the sequential extraction procedure the reducible fraction (hydroxylammonium chloride leach) showed the highest REE, but this is largely attributable to Ce4+ in oxide layers. Analysis of laterite profiles show that the REE distribution is heterogeneous, with control from both bedrock heterogeneity, and the hydrological variation between pedolith and saprolith. Similar patterns are seen in Chinese profiles from Jiangxi province. X-ray diffraction shows the clay fraction in all sites is dominated by kaolinite and halloysite. These data are consistent with experimental data which show that kaolinite is only HREE selective in high ionic strength solutions (Coppin et al., 2002), and suggest that HREE enrichment in lateritic deposits may be a function of exceptional bed rock conditions. Petrographic investigation of the Zhaibei granite, immediately underlying HREE enriched

  3. Eddies and dipoles around South Madagascar: formation, pathways and large-scale impact

    NASA Astrophysics Data System (ADS)

    de Ruijter, Wilhelmus P. M.; Aken, Hendrik M. van; Beier, Emilio J.; Lutjeharms, Johann R. E.; Matano, Ricardo P.; Schouten, Mathijs W.

    2004-03-01

    During a hydrographic cruise in March 2001, we encountered a dipole-like vortex structure directly southwest of Madagascar. The cruise formed part of the Dutch-South African Agulhas Current Sources Experiment (ACSEX). Direct current observations with a lowered ADCP showed that the multipole involved a deep-reaching central jet, with over 20 cm/s speeds still at 2000 m depth, with two contra-rotating eddies on either side. Both eddies had a size of about 250 km. A subsequent analysis of the combined TOPEX-POSEIDON/ERS altimeter dataset revealed the regular formation of dipoles around south Madagascar, where the East Madagascar Current (EMC) separates from the shelf. Between April 1995 and June 2000, 16 such features could be identified, six of which were formed between August 1996 and May 1997 and six between May 1999 and June 2000. These periods of enhanced dipole formation coincided with the negative phases of the Indian Ocean Dipole and El Niño cycles, suggesting a connection between these climate modes and the interannual variability in the periods of dipole train formation. The temperature-salinity characteristics of the eddies from the ACSEX dipole were identical to those measured in the EMC during the same cruise. The cyclonic eddy appeared to have drawn its waters from the inshore side of the EMC, suggesting it was formed as a lee-eddy on the cyclonic flank of the separating jet. The data indicate that the eddies carry their water along. At the observed scales, one dipole per year would feed 8 Sv (1 Sv=10 6 m 3/s) of EMC-derived water into the Agulhas retroflection region. In the Mozambique Basin, the eddy pairs behaved quite irregularly, with many of them splitting and interacting with other eddies in the region. The anticyclones then propagated mostly westward, while the cyclone tracks diverged more between west and southwest and were influenced by the interaction with the Mozambique Plateau. A very regular train of dipoles started in December 1999 and

  4. Evolution of high-pressure mafic granulites and pelitic gneisses from NE Madagascar: Tectonic implications

    NASA Astrophysics Data System (ADS)

    Ishwar-Kumar, C.; Sajeev, K.; Windley, B. F.; Kusky, T. M.; Feng, P.; Ratheesh-Kumar, R. T.; Huang, Y.; Zhang, Y.; Jiang, X.; Razakamanana, T.; Yagi, K.; Itaya, T.

    2015-11-01

    The occurrence of high-pressure mafic-ultramafic bodies within major shear zones is one of the indicators of paleo-subduction. In mafic granulites of the Andriamena complex (north-eastern Madagascar) we document unusual textures including garnet-clinopyroxene-quartz coronas that formed after the breakdown of orthopyroxene-plagioclase-ilmenite. Textural evidence and isochemical phase diagram calculations in the Na2O-CaO-K2O-FeO-MgO-Al2O3-SiO2-H2O-TiO2 system indicate a pressure-temperature (P-T) evolution from an isothermal (780 °C) pressure up to c. 24 kbar to decompression and cooling. Such a P-T trajectory is typically attained in a subduction zone setting where a gabbroic/ultramafic complex is subducted and later exhumed to the present crustal level during oceanic closure and final continental collision. The present results suggest that the presence of such deeply subducted rocks of the Andriamena complex is related to formation of the Betsimisaraka suture. LA-ICPMS U-Pb zircon dating of pelitic gneisses from the Betsimisaraka suture yields low Th/U ratios and protolith ages ranging from 2535 to 2625 Ma. A granitic gneiss from the Alaotra complex yields a zircon crystallization age of ca. 818 Ma and Th/U ratios vary from 1.08 to 2.09. K-Ar dating of muscovite and biotite from biotite-kyanite-sillimanite gneiss and garnet-biotite gneiss yields age of 486 ± 9 Ma and 459 ± 9 Ma respectively. We have estimated regional crustal thicknesses in NE Madagascar using a flexural inversion technique, which indicates the presence of an anomalously thick crust (c. 43 km) beneath the Antananarivo block. This result is consistent with the present concept that subduction beneath the Antananarivo block resulted in a more competent and thicker crust. The textural data, thermodynamic model, and geophysical evidence together provide a new insight to the subduction history, crustal thickening and evolution of the high-pressure Andriamena complex and its link to the terminal

  5. Hydrogeology in The Semi-Arid South-West of Madagascar - a Multi-Scale Approach

    NASA Astrophysics Data System (ADS)

    Englert, A.; Dworak, L.; Rasoloariniaina, J.; Brinkmann, K.; Kobbe, S.; Buerkert, A.

    2014-12-01

    The project „Sustainable Land Management" (SuLaMa) aims at the participatory development and implementation of alternative land-use management practices to protect the ecosystem and its biodiversity and improve the livelihood of the local population in a sustainable manner. One critical aspect within this project is the availability of sustainable water resources. To approach reliable estimates about the availability and dynamics of the water resources, we started a study to understand in detail the hydrogeology of the South-West of Madagascar. As this area has an extend of about 40000 square kilometers, the study is based on a multi-scale approach. Rough large scale estimates are utilized to develop a general understanding of the hydrogeology in the South-West of Madagascar, which allows for large scale estimates of hydrogeology under changing boundary conditions like climate change. Detailed investigations at target villages of the SuLaMa project, combined with boundary conditions derived from the large scale hydrogeological model, allows for estimates of the local hydrogeology under changing boundary conditions like enhanced water abstraction. Although several governmental and nongovernmental institutions have been working on the water resources of the South-West of Madagascar in the past, only few sources on the hydrogeology of this area can be found in literature. To improve the data base we installed five automatic loggers in the area to measure groundwater levels as function of time and investigated in detail about one hundred wells in terms of geometry, groundwater level, electrical conductivity and pH. First preliminary results of the study show that the hydrogeology in the study area is dominated by four major hydrogeological units (fractured crystalline basement, karstic plateau, porous perched aquifers and a porous coastal area) and can be analyzed effectively by assuming a radial symmetric geometry. Ongoing efforts are the development of a model for

  6. Premier cas d'un sub-fossile d'araignée appartenant au genre Archaea Koch & Berendt (Archaeidae) dans le copal de Madagascar

    NASA Astrophysics Data System (ADS)

    Lourenço, Wilson R.

    2000-04-01

    The first known case of a sub-fossil of a spider belonging to the genus Archaea from the Madagascan copal. The first known sub-fossil of a spider belonging to the genus Archaea Koch & Berendt is described from the Copal of Madagascar. The new species was found in the Province of Antseranana (Diego-Suarez) in the northern part of the island. It belongs to the family Archaeidae. The genus Archaea is endemic in Madagascar.

  7. Malagasyprinus, a new genus of the Saprininae from Madagascar with description of two new species (Coleoptera, Histeridae, Saprininae) (First contribution to the knowledge of the Histeridae of Madagascar).

    PubMed

    Lackner, Tomáš; Gomy, Yves

    2013-01-01

    Based on the results of recent phylogenetic analysis of the higher taxa of the Saprininae as well as external morphological characters, especially the presence of deep and large prosternal foveae, and the shape and position of the sensory organs of the antennal club, the species Saprinus (s.str.) caeruleatus Lewis, 1905 is excluded from the genus Saprinus and a new genus Malagasyprinus, exclusive to Madagascar, is established for it. The new genus shows mainly characters that are apomorphic for the subfamily and contains another two, highly similar allopatric species Malagasyprinus perrieri sp. n., and Malagasyprinus diana sp. n., described herein. The three species are best separated from each other by the structure of the prosternum and male terminalia, especially the shape of the aedeagus. We re-describe Malagasyprinus caeruleatus comb. n. and provide Malagasyprinus perrieri and Malagasyprinus diana with brief differential diagnoses. All taxon descriptions are accompanied with color habitat photographs, SEM micrographs and drawings of their male genitalia. A key to the species of Malagasyprinus is given. Sensory structures of the antenna of Malagasyprinus caeruleatus comb. n. are likewise depicted herein. The systematic position of the newly erected genus is discussed. A lectotype of Saprinus caeruleatus Lewis, 1905 is designated.

  8. Checklist of fishes from madagascar reef, campeche bank, méxico.

    PubMed

    Zarco Perello, Salvador; Moreno Mendoza, Rigoberto; Simões, Nuno

    2014-01-01

    This study presents the first list of fish species from Madagascar Reef, Campeche Bank, Gulf of México. Field surveys and literature review identified 54 species belonging to 8 orders, 30 families and 43 genera, comprising both conspicuous and cryptic fishes. Species richness was lower at this reef site compared to reefs in the Mexican Caribbean, Veracruz or Tuxpan, but was similar to other reefs in the same region. Species composition was a mixture of species present in all the reef systems of the Mexican Atlantic. Hypoplectrusecosur was recorded here for the first time in the Gulf of Mexico, Mycteropercamicrolepis, Equetuslanceolatus and Chaetodipterusfaber were new records for the reefs of the Campeche Bank, Elacatinusxanthiprora was recorded for the second time in Mexico and expanded its known distribution westwards from Alacranes Reef and Sanopusreticulatus, endemic of the Yucatan state, was recorded here for the first time on a reef.

  9. Valuing tropical forests: Methodology and case study of madagascar. World Bank environment paper

    SciTech Connect

    Kramer, R.A.; Sharma, N.; Munasinghe, M.

    1995-08-01

    The loss of large areas of tropical forests has become a major concern of the world community. Although there are many causes of tropical deforestation and forest degradation, an important cause appears to be undervaluation of forests by markets and governments. This volume examines some causes of tropical deforestation and explores forest valuation issues in the context of a protected area project. Part A (Chapters 1 and 2) sets out the context of tropical deforestation and loss of diodiversity and provides a framework for examining the economic value of forests. Part B (Chapter 3 to 8) is devoted to a detailed case study of Madagascar that illustrates the practical application of the techniques of analysis of the valuation of forests described earlier. Finally, the main findings and conclusions of this volume are summarized in Part C.

  10. Cytotoxic Prenylated Stilbenes and Flavonoids from Macaranga alnifolia from the Madagascar Rainforest#

    PubMed Central

    Yoder, Brent J.; Cao, Shugeng; Norris, Andrew; Miller, James S.; Ratovoson, Fidy; Razafitsalama, Jeremi; Andriantsiferana, Rabodo; Rasamison, Vincent E.; Kingston, David G. I.

    2008-01-01

    Bioassay-guided fractionation of an extract of the fruit of Macaranga alnifolia from Madagascar led to the isolation of four new prenylated stilbenes, schweinfurthins E–H (1–4), and one new geranylated dihydroflavonol, alnifoliol (5). The known prenylated stilbene, vedelianin (6), and the known geranylated flavonoids, bonanniol A (7), diplacol (8), bonannione A (9) and diplacone (10), were also isolated. All ten compounds were tested for antiproliferative activity in the A2780 human ovarian cancer cell line assay. Vedelianin (IC50 = 0.13 µM) exhibited the greatest activity among all isolates, while schweinfurthin E (IC50 = 0.26 µM) was the most potent of the new compounds. PMID:17326683

  11. A new and aberrant species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from Madagascar

    PubMed Central

    Stocchino, Giacinta Angela; Sluys, Ronald; Manconi, Renata

    2014-01-01

    Abstract In this paper we report a new species of Dugesia of the family Dugesiidae from Madagascar, representing the fourth species of freshwater planarian known from this global biodiversity hotspot. In some respects the new species is aberrant, when compared with its congeners, being characterized by a head with smoothly rounded auricles, a peculiar course of the oviducts, including the presence of a common posterior extension, and by the asymmetrical openings of the vasa deferentia at about halfway along the seminal vesicle. Further, it is characterized by a ventral course of the ejaculatory duct with a terminal opening, very long spermiducal vesicles and unstalked cocoons. Its diploid chromosome complement with 18 chromosomes represents an uncommon feature among fissiparous species of Dugesia. PMID:25147450

  12. Chemical composition of the essential oil from Croton kimosorum, an endemic species to Madagascar.

    PubMed

    Rabehaja, Delphin J R; Ihandriharison, Harilala; Ramanoelina, Panja A R; Benja, Rakotonirina; Ratsimamanga-Urverg, Suzanne; Bighelli, Ange; Casanova, Joseph; Tomi, Félix

    2014-01-01

    Croton kimosorum Leandri is an endemic species to Madagascar. The chemical composition of aerial parts, leaf and stem oils is reported for the first time. Analysis was carried out by combination of chromatographic (CC, GC), spectroscopic and spectrometric (MS, 13C NMR) techniques. In total, 76 compounds have been identified. Essential oil isolated from aerial parts contained mainly linalool (21.6%), sabinene (10.4%), 1,8-cineole (6.3%), beta-pinene (6.2%), (E)-beta-caryophyllene (5.9%), terpinen-4-ol (4.8%), geraniol (4,5%) and germacrene D (2.3%). In comparison with the first sample, the composition of leaf and stem oils varied slightly, while essential oil isolated by vapor distillation from a semi-industrial still exhibited similar composition.

  13. Anjozorobe hantavirus, a new genetic variant of Thailand virus detected in rodents from Madagascar.

    PubMed

    Reynes, Jean-Marc; Razafindralambo, Nadia Kaloina; Lacoste, Vincent; Olive, Marie-Marie; Barivelo, Tony Andrianaivo; Soarimalala, Voahangy; Heraud, Jean-Michel; Lavergne, Anne

    2014-03-01

    Until now, there was only serological evidence that hantaviruses were circulating in rodents and infecting humans from Madagascar. To assess the presence of a hantavirus on the island, between October, 2008, and March, 2010, we sampled 585 rodents belonging to seven species in the Anjozorobe-Angavo forest corridor, 70 km north from the capital city Antananarivo. A hantavirus was detected from organs of the ubiquist roof rat (Rattus rattus) and of the endemic Major's tufted-tailed rat (Eliurus majori). Amazingly, sequence analysis of the S (small), M (medium), and L (large) coding DNA sequence of this virus showed that the Anjozorobe strain (proposed name) was a new genetic variant of Thailand virus (THAIV) that comprises other variants found in Southeast Asia. Because THAIV is suspected of causing hemorrhagic fever with renal syndrome in humans, ongoing studies are addressing the risk of infection by this new variant in the Malagasy population.

  14. Gold deposit styles and placer gold characterisation in northern and east-central Madagascar

    USGS Publications Warehouse

    Pitfield, Peter E. J; Styles, Michael T.; Taylor, Cliff D.; Key, Roger M.; Bauer,; Ralison, A

    2009-01-01

    Microchemical characterisation of bedrock and placer gold grains from six gold districts within the Archaean domains and intervening Neoproterozoic Anaboriana-Manampotsy belt of northern and east-central Madagascar show few opaque inclusions (e.g pyrrhotite, Bi tellurides) but wide range of Ag contents (40wt%). Some districts exhibit multiple source populations of grains. The ‘greenstone belt’ terranes have an orogenic gold signature locally with an intrusion-related to epithermal overprint. Proterozoic metasediments with felsic to ultramafic bodies yield dominantly intrusion-related gold. A high proportion of secondary gold (<0.5wt% Ag) is related to recycling of paleoplacers and erosion of post-Gondwana planation surfaces and indicates that some mesothermal gold systems were already partially to wholly removed by erosion by the PermoTriassic.

  15. Genome assembly and annotation of a Drosophila simulans strain from Madagascar.

    PubMed

    Palmieri, Nicola; Nolte, Viola; Chen, Jun; Schlötterer, Christian

    2015-03-01

    Drosophila simulans is a close relative of the genetic model D. melanogaster. Its worldwide distribution in combination with the absence of segregating chromosomal inversions makes this species an increasingly attractive model to study the molecular signatures of adaptation in natural and experimental populations. In an effort to improve the genomic resources for D. simulans, we assembled and annotated the genome of a strain originating from Madagascar (M252), the ancestral range of D. simulans. The comparison of the M252 genome to other available D. simulans assemblies confirmed its high quality, but also highlighted genomic regions that are difficult to assemble with NGS data. The annotation of M252 provides a clear improvement with alternative splicing for 52% of the multiple-exon genes, UTRs for 70% of the genes, 225 novel genes and 781 pseudogenes being reported. We anticipate that the M252 genome will be a valuable resource for many research questions.

  16. A new arboreal frog of the genus Guibemantis from the southeast of Madagascar (Anura: Mantellidae).

    PubMed

    Vences, Miguel; Jovanovic, Olga; Safarek, Goran; Glaw, Frank; Köhler, Jörn

    2015-12-23

    We describe a new species of arboreal frog of the genus Guibemantis, subgenus Guibemantis, from low altitude rainforest in Manombo Special Reserve, south-eastern Madagascar. Previously published phylogenetic analyses of mitochondrial DNA sequences have placed Guibemantis diphonus sp. nov. sister to G. timidus. The new species is distinguished from G. timidus and all other species in the subgenus by a substantial genetic differentiation (≥ 4.4% uncorrected p-distance in the mitochondrial 16S rRNA gene), strongly divergent advertisement call, and some limited morphological differences. It is the smallest known species in the subgenus, with 34-36 mm snout-vent length in adult males. Its advertisement call is unique among other species in the subgenus in being composed of two distinctly different note types (only one note type in the other species).

  17. The Persistence of Self-Provisioning Among Smallholder Farmers in Northeast Madagascar.

    PubMed

    Laney, Rheyna; Turner, B L

    In the Andapa region of northeast Madagascar, smallholders cultivating swidden hill rice (tavy) for subsistence are pressing against neighboring nature reserves. A dominant policy approach to reducing this pressure requires that smallholders abandon tavy and purchase rice from proceeds obtained from their environmentally sustainable commercial crops, vanilla and coffee. Economic liberalization policies have succeeded in stimulating the expansion of these commercial crops, but have failed to reduce tavy production. We ask why this dual (subsistence and commercial) production system persists. We test two explanatory views: that either market imperfections deny farmers full entry into the market, or that internal production goals or socio-cultural norms create barriers to full market participation. Results support the latter view, although not for reasons that have been associated with this view in past studies. We propose a new factor that may serve as a barrier to full-market immersion among Andapa tavy farmers, the social relations of property.

  18. The complete mitochondrial genome of the Madagascar ground gecko Paroedura picta (Squamata: Gekkonidae).

    PubMed

    Starostová, Zuzana; Musilová, Zuzana

    2016-11-01

    We sequenced the complete mitochondrial genome of the Madagascar ground gecko Paroedura picta (Squamata: Gekkonidae). The mitogenome is 17 220 base pairs long and conforms to the typical vertebrate gene composition and arrangement, i.e. 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes and 1919 bp long control region. We reconstructed phylogenetic relationships of P. picta and representatives of nine other genera from the family Gekkonidae and calculated mean p-distances for all 13 protein-coding mitochondrial genes. The lowest mean p-distances were found in cytochrome oxidase subunit I and III genes (COI and COIII) indicating their usefulness for elucidating deeper phylogenetic relationships.

  19. Normal developmental stages of the Madagascar ground gecko Paroedura pictus with special reference to limb morphogenesis.

    PubMed

    Noro, Miyuki; Uejima, Asaka; Abe, Gembu; Manabe, Makoto; Tamura, Koji

    2009-01-01

    A table of developmental stages of the target species is useful for studying the development of any animal. Although tables of developmental stages have been established for several squamates, none has been published for gekkonid lizards. We have established a table of developmental stages for the Madagascar ground gecko Paroedura pictus. The table includes 27 embryonic stages from oviposition to hatching based on chronology and external morphology. The interval from oviposition to hatching is 60 days. Eleven to sixteen somites were observed at oviposition, and 5 to 6 somites were formed each day. Limb bud swellings were recognized by the third day after oviposition. After 2 weeks of incubation, the presumptive autopod was detected by carpal/tarsal cartilage formation. Cartilages in all digits were seen by 3 weeks after oviposition. Skin pigment was visible after 4 weeks incubation, and the skin color pattern was apparent 40 days after oviposition. Copyright (c) 2008 Wiley-Liss, Inc.

  20. The impact of malaria chemoprophylaxis in Africa with special reference to Madagascar, Cameroon, and Senegal

    PubMed Central

    Laing, A. B. G.

    1984-01-01

    Some past and present experiences in the use of antimalarial drugs, particularly for chemoprophylaxis, are reviewed. The failure in the long term of mass chemoprophylaxis with weekly chloroquine in children in Madagascar, Cameroon, and Senegal is discussed, the reasons for failure being an increasing lack of resources to ensure regular drug distribution and lack of supervision of dosage. The increasing number of reports confirming chloroquine resistance from East Africa over the last decade poses a serious threat to the future usefulness of chloroquine as an antimalarial agent in Africa. There is now an urgent need for extensive drug sensitivity tests, which should also include alternative antimalarial drugs. To rely on mass chemoprophylaxis as the main method of controlling malaria would appear to be no longer tenable. PMID:6397276

  1. Red Algae (Rhodophyta) from the Coast of Madagascar: Preliminary Bioactivity Studies and Isolation of Natural Products.

    PubMed

    Rahelivao, Marie Pascaline; Gruner, Margit; Andriamanantoanina, Hanta; Andriamihaja, Bakolinirina; Bauer, Ingmar; Knölker, Hans-Joachim

    2015-07-07

    Several species of red algae (Rhodophyta) from the coastal regions of Madagascar have been investigated for their natural products. The most abundant compound was cholesterol (5) in combination with a series of oxidized congeners. The brominated indoles 1-3 along with the sesquiterpene debilone (4) have been isolated from Laurencia complanata. For the first time, debilone (4) has been obtained from a marine plant. From the methanol extract of Calloseris sp., we have achieved the second isolation of the unusual A-ring contracted steroids (-)-2-ethoxycarbonyl-2β-hydroxy-A-nor-cholest-5-en-4-one (9) and phorbasterone B (10). The crude extracts of Laurencia complanata exhibited antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Streptococcus pneumoniae, and Candida albicans.

  2. Brown Algae (Phaeophyceae) from the Coast of Madagascar: preliminary Bioactivity Studies and Isolation of Natural Products.

    PubMed

    Rahelivao, Marie Pascaline; Gruner, Margit; Andriamanantoanina, Hanta; Bauer, Ingmar; Knölker, Hans-Joachim

    2015-10-01

    Eight species of brown algae (Phaeophyceae) from the coast of Madagascar have been investigated for their chemical constituents. Fucosterol (3) was obtained as the most abundant compound. The brown alga Sargassum ilicifolium was the source for the first isolation of the terpenoid C27-alcohol 1,1',2-trinorsqualenol (1) from marine sources. From S. incisifolium we isolated the highly unsaturated glycolipid 1-O-palmitoyl-2-O-stearidonoyl-3-O-β-D-galactopyranosylglycerol (4) and we report the first full assignment of its (1)H and (13)C NMR data. Apo-9'-fucoxanthinone (8) along with 24-ketocholesterol (5), (22E)-3β-hydroxycholesta-5,22-dien-24-one (6), and saringosterol (7) were obtained from Turbinaria ornata. The crude extracts of all eight species of brown algae exhibited a pronounced antimicrobial activity against the Gram-positive bacteria Bacillus cereus, Staphylococcus aureus, and Streptococcus pneumoniae.

  3. Anjozorobe Hantavirus, a New Genetic Variant of Thailand Virus Detected in Rodents from Madagascar

    PubMed Central

    Razafindralambo, Nadia Kaloina; Lacoste, Vincent; Olive, Marie-Marie; Barivelo, Tony Andrianaivo; Soarimalala, Voahangy; Heraud, Jean-Michel; Lavergne, Anne

    2014-01-01

    Abstract Until now, there was only serological evidence that hantaviruses were circulating in rodents and infecting humans from Madagascar. To assess the presence of a hantavirus on the island, between October, 2008, and March, 2010, we sampled 585 rodents belonging to seven species in the Anjozorobe-Angavo forest corridor, 70 km north from the capital city Antananarivo. A hantavirus was detected from organs of the ubiquist roof rat (Rattus rattus) and of the endemic Major's tufted-tailed rat (Eliurus majori). Amazingly, sequence analysis of the S (small), M (medium), and L (large) coding DNA sequence of this virus showed that the Anjozorobe strain (proposed name) was a new genetic variant of Thailand virus (THAIV) that comprises other variants found in Southeast Asia. Because THAIV is suspected of causing hemorrhagic fever with renal syndrome in humans, ongoing studies are addressing the risk of infection by this new variant in the Malagasy population. PMID:24575755

  4. Detection of a Novel DSPP Mutation by NGS in a Population Isolate in Madagascar

    PubMed Central

    Bloch-Zupan, Agnès; Huckert, Mathilde; Stoetzel, Corinne; Meyer, Julia; Geoffroy, Véronique; Razafindrakoto, Rabisoa W.; Ralison, Saholy N.; Randrianaivo, Jean-Claude; Ralison, Georgette; Andriamasinoro, Rija O.; Ramanampamaharana, Rija H.; Randrianazary, Solofomanantsoa E.; Ralimanana, Louise H.; Richard, Béatrice; Gorry, Philippe; Manière, Marie-Cécile; Rasoamananjara, Jeanne A.; Rakoto Alson, Simone; Dollfus, Hélène

    2016-01-01

    A large family from a small village in Madagascar, Antanetilava, is known to present with colored teeth. Through previous collaboration and 4 successive visits in 1994, 2004, 2005, and 2012, we provided dental care to the inhabitants and diagnosed dentinogenesis imperfecta. Recently, using whole exome sequencing we confirmed the clinical diagnosis by identifying a novel single nucleotide deletion in exon 5 of DSPP. This paper underlines the necessity of long run research, the importance of international and interpersonal collaborations as well as the major contribution of next generation sequencing tools in the genetic diagnosis of rare oro-dental anomalies. This study is registered in ClinicalTrials (https://clinicaltrials.gov) under the number NCT02397824. PMID:26973538

  5. Earth observations of Northern Madagascar taken from Columbia during STS-93 mission

    NASA Image and Video Library

    1999-07-24

    STS093-722-051 (23-27 July 1999) --- The STS-93 astronauts aboard the Space Shuttle Columbia took this picture over the Indian Ocean. The distinctive arrowhead shape of the northern tip of the island of Madagascar is easily recognizable. The land appears red with patches of dark green on the upper slopes. According to NASA scientists studying the STS-93 photo collection, the dark areas are the remnants of forests and the red areas are cleared land. When the photo was taken, the shuttle was flying over a point located at 14.7 degrees south latitude and 44.0 degrees east longitude. Data back information on the 70mm film listed the date and time of the photo as 11:38:20 GMT, July 24, 1999 (Orbit 21).

  6. Impact of a training package for community birth attendants in Madagascar.

    PubMed

    Lucey, Olivia; Andriatsihosena, Mamy; Ellis, Matthew

    2011-02-01

    This brief report assesses the impact of community birth attendant training and explores barriers to safe delivery in rural Madagascar. We assessed the knowledge of 25 community birth attendants using interviewer-administered questionnaires and explored attitudes to delivery in 4 focus groups of 10 women of reproductive age and 1 focus group of 10 birth attendants. We found a mismatch between hygiene knowledge and reported practice. Clinical experience appears to reinforce training to achieve longer lasting change in practitioner knowledge (e.g. of labour complications). Focus groups helped to identify practical barriers to clean (delivery kits) and safe delivery (cost) despite this knowledge. We proposed that a facilitated women's group programme may complement such training.

  7. Pilot survey of avahi population (woolly lemurs) in littoral forest fragments of southeast Madagascar.

    PubMed

    Norscia, Ivan

    2008-01-01

    This study presents a pilot survey of the avahis (pair-living, nocturnal prosimians) living in threatened littoral forest fragments of southeastern Madagascar. In the period of October-December 2004, I evaluated the density of adult and newborn avahis (carried by the mothers) by counting the individuals encountered during 58 night walks in seven fragments of Sainte Luce and Mandena forests, along one trail/fragment. Along each trail, I used random plots (5 m2) for a preliminary characterization of the vegetation. The density of the population was not correlated with fragment size and number of plant morphospecies, while it was correlated with large tree availability. Possibly due to a low energy diet based on leaves and to specialized and energetically expensive vertical leaping, the loss of large trees by selective logging seems to affect avahi populations more than other variables.

  8. Characterization of a biphasic neoplasm in a Madagascar tree boa (Sanzinia madagascariensis).

    PubMed

    Bera, M M; Veeramachaneni, D N R; Pandher, K

    2008-03-01

    We describe a disseminated biphasic neoplasm in a young Madagascar tree boa utilizing transmission electron and light microscopy. Discrete neoplastic cells identified within pulmonary capillaries and hepatic sinusoids represented the leukemic phase. Spindloid cells represented the sarcomatous phase, which comprised hepatic and fat body nodules. A zone of transition of the neoplastic cells, from discrete to spindloid, was noted along the periphery of the hepatic and fat body nodules. Ultrastructural examination elucidated similar nuclear features in the discrete and spindloid neoplastic cells and revealed collagen fibers within the spindloid neoplastic cells. These ultrastructural findings indicate that the discrete and spindloid cells represent a single neoplastic process with a subpopulation of cells exhibiting mesenchymal differentiation.

  9. Diagnosis and treatment of a pharyngeal squamous cell carcinoma in a Madagascar ground boa (Boa madagascariensis).

    PubMed

    Steeil, James C; Schumacher, Juergen; Hecht, Silke; Baine, Katherine; Ramsay, Edward C; Ferguson, Sylvia; Miller, Debra; Lee, Nathan D

    2013-03-01

    A 15-yr-old female Madagascar ground boa (Boa madagascariensis) presented with a history of anorexia, wheezing, and occasional open-mouth breathing. On oral examination, a firm, caseous mass was noted in the right caudoventral pharyngeal region, which was confirmed as a carcinoma on incisional biopsy. Advanced imaging (computed tomography and magnetic resonance imaging) was performed to evaluate local tumor invasion and to plan for palliative radiation therapy. However, following the second treatment (10 Gy), the mass had increased in size, and the snake was euthanatized. Radiation-associated vasculitis was noted within the soft tissues surrounding the mass and within muscles and the lung, which was verified on histopathology. The squamous cell carcinoma of the snake in this report was resistant to palliative radiation therapy.

  10. A necessarily complex model to explain the biogeography of the amphibians and reptiles of Madagascar.

    PubMed

    Brown, Jason L; Cameron, Alison; Yoder, Anne D; Vences, Miguel

    2014-10-09

    Pattern and process are inextricably linked in biogeographic analyses, though we can observe pattern, we must infer process. Inferences of process are often based on ad hoc comparisons using a single spatial predictor. Here, we present an alternative approach that uses mixed-spatial models to measure the predictive potential of combinations of hypotheses. Biodiversity patterns are estimated from 8,362 occurrence records from 745 species of Malagasy amphibians and reptiles. By incorporating 18 spatially explicit predictions of 12 major biogeographic hypotheses, we show that mixed models greatly improve our ability to explain the observed biodiversity patterns. We conclude that patterns are influenced by a combination of diversification processes rather than by a single predominant mechanism. A 'one-size-fits-all' model does not exist. By developing a novel method for examining and synthesizing spatial parameters such as species richness, endemism and community similarity, we demonstrate the potential of these analyses for understanding the diversification history of Madagascar's biota.

  11. Cytotoxic cardenolide glycosides of Roupellina (Strophanthus) boivinii from the Madagascar rainforest1

    PubMed Central

    Karkare, Sampada; Adou, Eba; Cao, Shugeng; Brodie, Peggy; Miller, James S.; Andrianjafy, N. M.; Razafitsalama, J.; Andriantsiferana, Rabodo; Rasamison, Vincent E.; Kingston, David G. I.

    2008-01-01

    Bioassay-guided fractionation of an ethanol extract of Roupellina (Strophanthus) boivinii from the rainforest of Madagascar afforded the six new cardenolide glycosides boivinides 1–6, as well as the four known cardenolide glycosides, digitoxigenin 3-O-[β-D-glucopyrananosyl-(1→4)-α-L-acofriopyranoside], corotoxigenin 3-O-β-D-boivinoside, 17βH-corotoxigenin 3-O-β-D-sarmentoside, and uzarigenin 3-O-α-L-rhamnoside. The structures of these compounds were elucidated by various 1D and 2D NMR techniques. All new compounds showed significant antiproliferative activity against A2780 human ovarian cancer cell line, with boivinide A being the most active at IC50 = 0.17 μM. PMID:17988099

  12. Morphometrics, sexual dimorphism, and growth in the Angonoka tortoise (Geochelone yniphora) of western Madagascar

    USGS Publications Warehouse

    Smith, Lora L.; Pedrono, Miguel; Dorazio, Robert M.; Bishko, Jack

    2001-01-01

    The most recent description of the morphology of the rare endemic Madagascar tortoise,Geochelone yniphora was based on fewer than 20 specimens. We collected morphological data for 200 free‐ranging tortoises from five populations over a four‐year period. Tortoises ranged in size from 43.5 mm carapace length at hatching to a maximum of 481 mm in an adult male. We were able to develop a logistic regression model to predict the sex of adult tortoises in one of the five populations using principal component analysis; the model correctly predicted the sex of 25 of 26 adult tortoises. Growth of 40 tortoises was monitored and as in other chelonians, the annual relative growth rate decreased with age. The relative growth rate in adults was approximately 5% per year as compared to approximately 16% in juveniles. Juvenile tortoises accrued one scute growth layer per year.

  13. Thermoluminescence External Personnel Monitoring of Workers in Diagnostic Radiology in Madagascar

    NASA Astrophysics Data System (ADS)

    Andriambololona, Raoelina; Ratovonjanahary, J. F.; Randriantsizafy, R. D.; Rakotoson, E.; Razafindrabe, R. L.

    2002-07-01

    Results of thermoluminescence personnel external monitoring are reported from 1990 to 2000 for workers in diagnostic radiology which represents more than 75% of the professional exposure in Madagascar and for which enough data for good statistical considerations are available. Average and individual doses distribution are presented. In most cases, compliance with dose limits is verified though some high exposures have been identified. Globaly, these doses can be compared with the average effective dose from natural radiation sources. Methods for the evaluation of quality and performance are presented as long as the doses measured are all in the low range. In radiation protection, an important principle is to meet the requirements of the implementation of ALARA, in order to limit or reduce exposures. This work can be used as reference for decision makers for corrective measures or further investigation when substantial variation in average doses is observed.

  14. How Effective Have Thirty Years of Internationally Driven Conservation and Development Efforts Been in Madagascar?

    PubMed Central

    Wilmé, Lucienne; Mercier, Jean-Roger; Camara, Christian; Lowry, Porter P.

    2016-01-01

    Conservation and development are intricately linked. The international donor community has long provided aid to tropical countries in an effort to alleviate poverty and conserve biodiversity. While hundreds of millions of $ have been invested in over 500 environmental-based projects in Madagascar during the period covered by a series of National Environmental Action Plans (1993–2008) and the protected areas network has expanded threefold, deforestation remains unchecked and none of the eight Millennium Development Goals (MDGs) established for 2000–2015 were likely be met. Efforts to achieve sustainable development had failed to reduce poverty or deliver progress toward any of the MDGs. Cross-sectorial policy adjustments are needed that (i) enable and catalyze Madagascar’s capacities rather than deepening dependency on external actors such as the World Bank, the International Monetary Fund and donor countries, and that (ii) deliver improvements to the livelihoods and wellbeing of the country’s rural poor. PMID:27532499

  15. [Teenage pregnancy in Madagascar: impact on the health of mother and child].

    PubMed

    Binet, Clotilde; Gastineau, Bénédicte; Rakotoson, Lina

    2009-01-01

    In committing itself to achieve the Millennium Development Goals, Madagascar committed itself to reducing maternal and infant mortality. Teenagers must be a target for activities to improve maternal and child health, for analyses of survey data show clearly that teenager pregnancies present a risk to the health of both young mothers and their children; in particular, both have a higher risk of death than older mothers and their children. These differences can be explained both by biological factors and socioeconomic variables (place of residence, educational level, etc). The issue of abortion is also important, for it is an important cause of maternal mortality, especially among young girls. Beyond the actions of prevention, post-abortion care could help to reduce the complications of abortions and thus mortality among women.

  16. [Premarital sex in Antananarivo (Madagascar): how are students freeing themselves from the norms?].

    PubMed

    Gastineau, Bénédicte; Binet, Clotilde

    2013-06-01

    This paper aims to analyze the representations of premarital sexuality among young people in a context where they are strongly encouraged not to engage in premarital sexual relations. This link between prevention messages, representations and behaviours has been studied among a student population in Madagascar. The analysis is based on a socio-demographic survey conducted in 2006. Results show that young men and women share the ideal of abstinence before marriage. The promotion of premarital sexual abstinence within AIDS programs reinforces gender differences. It is mainly young women who are urged to be abstinent, whereas young men have the means--condom use--to transgress the taboo of premarital sex and protect themselves against health risks. Thus, young men have a dual strategy. On the one hand, they attach great importance to premarital abstinence with their future wife; on the other hand, they can have sex with occasional partners and are then protected by condoms.

  17. Checklist of Fishes from Madagascar Reef, Campeche Bank, México

    PubMed Central

    2014-01-01

    Abstract This study presents the first list of fish species from Madagascar Reef, Campeche Bank, Gulf of México. Field surveys and literature review identified 54 species belonging to 8 orders, 30 families and 43 genera, comprising both conspicuous and cryptic fishes. Species richness was lower at this reef site compared to reefs in the Mexican Caribbean, Veracruz or Tuxpan, but was similar to other reefs in the same region. Species composition was a mixture of species present in all the reef systems of the Mexican Atlantic. Hypoplectrus ecosur was recorded here for the first time in the Gulf of Mexico, Mycteroperca microlepis, Equetus lanceolatus and Chaetodipterus faber were new records for the reefs of the Campeche Bank, Elacatinus xanthiprora was recorded for the second time in Mexico and expanded its known distribution westwards from Alacranes Reef and Sanopus reticulatus, endemic of the Yucatan state, was recorded here for the first time on a reef. PMID:24891834

  18. Earth observations of Northern Madagascar taken from Columbia during STS-93 mission

    NASA Image and Video Library

    1999-07-26

    STS093-716-065 (23-27 July 1999) --- The STS-93 astronauts aboard the Space Shuttle Columbia took this picture of a sunrise on the Mozambique Channel along the coast of Madagascar. The nearest point of land is Cape Saint Andre, which forms the northwest corner of the island. Sunglint highlights the land-water boundary along a series of dynamic estuaries. The fifth inlet from the bottom just above the small lake is the Betsiboka Estuary. When the photo was taken, the shuttle was flying over a point located at 18.7 degrees south latitude and 36.1 degrees east longitude. Data back information on the 70mm film listed the time and date as 03:40:43 GMT, July 26, 1999 (orbit 48).

  19. The Burden of Acute Disease in Mahajanga, Madagascar – A 21 Month Study

    PubMed Central

    Kannan, Vijay C.; Andriamalala, Clara N.; Reynolds, Teri A.

    2015-01-01

    Background Efforts to develop effective and regionally-appropriate emergency care systems in sub-Saharan Africa are hindered by a lack of data on both the burden of disease in the region and on the state of existing care delivery mechanisms. This study describes the burden of acute disease presenting to an emergency unit in Mahajanga, Madagascar. Methods and Findings Handwritten patient registries on all emergency department patients presenting between 1 January 2011 and 30 September 2012 were reviewed and data entered into a database. Data included age, sex, diagnosis, and disposition. We classified diagnoses into Clinical Classifications Software (CCS) multi-level categories. The population was 53.5% male, with a median age of 31 years. The five most common presenting conditions were 1) Superficial injury; contusion, 2) Open wounds of head; neck; and trunk, 3) Open wounds of extremities, 4) Intracranial injury, and 5) Unspecified injury and poisoning. Trauma accounted for 48%, Infectious Disease for 15%, Mental Health 6.1%, Noncommunicable 29%, and Neoplasms 1.2%. The acuity seen was high, with an admission rate of 43%. Trauma was the most common reason for admission, representing 19% of admitted patients. Conclusions This study describes the burden of acute disease at a large referral center in northern Madagascar. The Centre Hôpitalier Universitaire de Mahajanga sees a high volume of acutely ill and injured patients. Similar to other reports from the region, trauma is the most common pathology observed, though infectious disease was responsible for the majority of adult mortality. Typhoid fever other intestinal infections were the most lethal CCS-coded pathologies. By utilizing a widely understood classification system, we are able to highlight contrasts between Mahajanga’s acute and overall disease burden as well as make comparisons between this region and the rest of the globe. We hope this study will serve to guide the development of context

  20. Lost in translation: conflicting views of deforestation, land use and identity in western Madagascar.

    PubMed

    Scales, Ivan R

    2012-01-01

    This paper focuses on the interplay between environmental narratives, identity politics and the management of forest resources in Madagascar. While efforts to conserve the island's biological diversity have centred primarily on the designation of protected areas, policies have increasingly focused on local communities. The experiences of the last 20 years have shown that community-based approaches to conservation offer considerable challenges due to the complex politics of natural resource use, which involve multiple and diverse stakeholders, often with very different and sometimes conflicting values. In this paper, I focus on the environmental perceptions and values of two groups in the Central Menabe region of western Madagascar – conservation organisations and rural households – revealing a contrasting set of views regarding the region's forest. I show that the conservation discourse has changed over time, increasingly emphasising the biological diversity of the region's tropical dry-deciduous forest and prioritising non-consumptive uses of natural resources. Although policy has changed in response to changing values, I show that it has been underpinned by the notion that hatsake (‘slash-and-burn’ agriculture) is an irrational practice driven by necessity rather than choice. Policy has thus sought to provide livelihood alternatives, firstly through forestry, then through changes in cultivation and increasingly through tourism. This misunderstands the local view of the forest, which sees hatsake as a way to make the land productive, as long as it is carried out responsibly according to local fady (taboos). As well as facing problems of translating conservation goals into local values and misunderstanding the motives for forest clearance, policy has been based on a narrative that attaches particular land use practices to ethnic identities. I argue that this ignores the history and fluid reality of both identity and land use.

  1. Radiogenic heating to ultrahigh temperature: Geochronology and 4+ thermometry across southern Madagascar

    NASA Astrophysics Data System (ADS)

    Horton, F.; Hacker, B. R.; Kylander-Clark, A. R.

    2014-12-01

    As zones of focused metamorphism, melting, and ductile deformation, hot crustal sections are especially important for understanding the evolution of the lower crust in convergent orogens, such as Tibet. One of the best exposed crustal sections that reached ultrahigh-temperature (UHT: >900° C) is in southern Madagascar. There, the association of UHT mineral assemblages with exceptionally high concentrations of radioactive heat-producing elements begs the question of whether radiogenic heating caused UHT. Partial melting, retrogression and rapid elemental diffusion at high temperature, however, have left a complex record of radiometric dates that span 150 Myr (~650-500 Ma), making it difficult to address this question. We apply laser-ablation split-stream ICPMS (LASS) petrochronology and 4+ cation thermometry to better constrain the lengthscales and timescales over which high temperatures were sustained in southern Madagascar. By deciphering complex intragrain (re)crystallization textures of zircon and monazite from a broad geographical area, we deduce that orogenesis lasted >60 Myr. Specifically, 600-540 Ma zircon and monazite with HREE depletion suggest (re)crystallization in the presence of garnet. All monazite show negative Eu anomalies (compatible with the presence of plagioclase), but ~570 to ~530 Ma monazite has more-pronounced anomalies. Ti-in-zircon and Zr-in-rutile thermometry confirm ultrahigh temperatures within a restricted area of ~100 x 200 km. These thermal and chronologic constraints allow us to evaluate the potential causes of heating. Measured K, Th, and U contents of rocks within the UHT domain indicate an average heat-production rate of >4 μW/m3, sufficient to produce UHT metamorphism in 60-km thick crust within 60 Myr. We conclude that high concentrations of heat-producing elements caused focused heat production in young metasedimentary rocks that were sandwiched between older crustal domains. We speculate that ultrahigh temperatures caused by

  2. Effectiveness of Fipronil as a Systemic Control Agent Against Xenopsylla cheopis (Siphonaptera: Pulicidae) in Madagascar.

    PubMed

    Rajonhson, D M; Miarinjara, A; Rahelinirina, S; Rajerison, M; Boyer, S

    2017-03-01

    Fipronil was evaluated as a systemic control agent for the rat flea Xenopsylla cheopis (Rothschild), the main vector of Yersinia pestis (Yersin), the causative agent of plague, in Madagascar. The effectiveness of fipronil as a systemic control agent against X. cheopis was assessed by determining the toxicity values of the "Lethal Dose 50" (LD50). Two techniques were used to evaluate the systemic action of the insecticide on the vector: 1) an artificial feeding device filled with blood-fipronil mixture from which X. cheopis was fed and 2) rodent hosts, Rattus norvegicus (Berkenhout) and Rattus rattus (L.), which fed on fipronil-treated bait. As a standardized control method, the susceptibility of X. cheopis to fipronil was evaluated by exposure to impregnated paper within World Health Organization (WHO) insecticide test protocol to compare its effect to the systemic activity of the studied insecticide. Results showed that when administered in a systemic way, fipronil appears to be more effective: the toxicity level was evaluated to be ninefold higher compared with the WHO test. Compared with other methods, which require indiscriminate dusting of rodent burrows and human dwellings, fipronil applied in a systemic way enables the direct targeting of the plague vector. Thus, this method appears to be a superior alternative to fipronil-dusting for the control of the main plague vector in Madagascar. However, subsequent tests in the field are necessary to confirm the suitability of fipronil administration in a systemic way on large scales. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Introducing auto-disable syringes to the national immunization programme in Madagascar.

    PubMed Central

    Drain, Paul K.; Ralaivao, Josoa S.; Rakotonandrasana, Alexander; Carnell, Mary A.

    2003-01-01

    OBJECTIVE: To evaluate the safety and coverage benefits of auto-disable (AD) syringes, weighed against the financial and logis- tical costs, and to create appropriate health policies in Madagascar. METHODS: Fifteen clinics in Madagascar, trained to use AD syringes, were randomized to implement an AD syringe only, mixed (AD syringes used only on non-routine immunization days), or sterilizable syringe only (control) programme. During a five-week period, data on administered vaccinations were collected, interviews were conducted, and observations were recorded. FINDINGS: The use of AD syringes improved coverage rates by significantly increasing the percentage of vaccines administered on non-routine immunization days (AD-only 4.3%, mixed 5.7%, control 1.1% (P<0.05)). AD-only clinics eliminated sterilization sessions for vaccinations, whereas mixed clinics reduced the number of sterilization sessions by 64%. AD syringes were five times more expensive than sterilizable syringes, which increased AD-only and mixed clinics' projected annual injection costs by 365% and 22%, respectively. However, introducing AD syringes for all vaccinations would only increase the national immunization budget by 2%. CONCLUSION: The use of AD syringes improved vaccination coverage rates by providing ready-to-use sterile syringes on non-routine immunization days and decreasing the number of sterilization sessions, thereby improving injection safety. The mixed programme was the most beneficial approach to phasing in AD syringes and diminishing logistical complications, and it had minimal costs. AD syringes, although more expensive, can feasibly be introduced into a developing country's immunization programme to improve vaccination safety and coverage. PMID:14576886

  4. A genome sequence resource for the aye-aye (Daubentonia madagascariensis), a nocturnal lemur from Madagascar.

    PubMed

    Perry, George H; Reeves, Darryl; Melsted, Páll; Ratan, Aakrosh; Miller, Webb; Michelini, Katelyn; Louis, Edward E; Pritchard, Jonathan K; Mason, Christopher E; Gilad, Yoav

    2012-01-01

    We present a high-coverage draft genome assembly of the aye-aye (Daubentonia madagascariensis), a highly unusual nocturnal primate from Madagascar. Our assembly totals ~3.0 billion bp (3.0 Gb), roughly the size of the human genome, comprised of ~2.6 million scaffolds (N50 scaffold size = 13,597 bp) based on short paired-end sequencing reads. We compared the aye-aye genome sequence data with four other published primate genomes (human, chimpanzee, orangutan, and rhesus macaque) as well as with the mouse and dog genomes as nonprimate outgroups. Unexpectedly, we observed strong evidence for a relatively slow substitution rate in the aye-aye lineage compared with these and other primates. In fact, the aye-aye branch length is estimated to be ~10% shorter than that of the human lineage, which is known for its low substitution rate. This finding may be explained, in part, by the protracted aye-aye life-history pattern, including late weaning and age of first reproduction relative to other lemurs. Additionally, the availability of this draft lemur genome sequence allowed us to polarize nucleotide and protein sequence changes to the ancestral primate lineage-a critical period in primate evolution, for which the relevant fossil record is sparse. Finally, we identified 293,800 high-confidence single nucleotide polymorphisms in the donor individual for our aye-aye genome sequence, a captive-born individual from two wild-born parents. The resulting heterozygosity estimate of 0.051% is the lowest of any primate studied to date, which is understandable considering the aye-aye's extensive home-range size and relatively low population densities. Yet this level of genetic diversity also suggests that conservation efforts benefiting this unusual species should be prioritized, especially in the face of the accelerating degradation and fragmentation of Madagascar's forests.

  5. Assessment of tuberculosis spatial hotspot areas in Antananarivo, Madagascar, by combining spatial analysis and genotyping.

    PubMed

    Ratovonirina, Noël Harijaona; Rakotosamimanana, Niaina; Razafimahatratra, Solohery Lalaina; Raherison, Mamy Serge; Refrégier, Guislaine; Sola, Christophe; Rakotomanana, Fanjasoa; Rasolofo Razanamparany, Voahangy

    2017-08-14

    Tuberculosis (TB) remains a public health problem in Madagascar. A crucial element of TB control is the development of an easy and rapid method for the orientation of TB control strategies in the country. Our main objective was to develop a TB spatial hotspot identification method by combining spatial analysis and TB genotyping method in Antananarivo. Sputa of new pulmonary TB cases from 20 TB diagnosis and treatment centers (DTCs) in Antananarivo were collected from August 2013 to May 2014 for culture. Mycobacterium tuberculosis complex (MTBC) clinical isolates were typed by spoligotyping on a Luminex® 200 platform. All TB patients were respectively localized according to their neighborhood residence and the spatial distribution of all pulmonary TB patients and patients with genotypic clustered isolates were scanned respectively by the Kulldorff spatial scanning method for identification of significant spatial clustering. Areas exhibiting spatial clustering of patients with genotypic clustered isolates were considered as hotspot TB areas for transmission. Overall, 467 new cases were included in the study, and 394 spoligotypes were obtained (84.4%). New TB cases were distributed in 133 of the 192 Fokontany (administrative neighborhoods) of Antananarivo (1 to 15 clinical patients per Fokontany) and patients with genotypic clustered isolates were distributed in 127 of the 192 Fokontany (1 to 13 per Fokontany). A single spatial focal point of epidemics was detected when ignoring genotypic data (p = 0.039). One Fokontany of this focal point and three additional ones were detected to be spatially clustered when taking genotypes into account (p < 0.05). These four areas were declared potential TB transmission hotspots in Antananarivo and will be considered as priority targets for surveillance in the future. This method, combining spatial analysis and TB genotyping will now be used for further focused clinical and epidemiological studies in Madagascar and will allow

  6. Competition for dead trees between humans and aye-ayes (Daubentonia madagascariensis) in central eastern Madagascar.

    PubMed

    Miller, Rose T; Raharison, Jean-Luc; Irwin, Mitchell T

    2017-04-01

    The destruction and degradation of forest habitats are major threats to the sustainability of lemur populations in Madagascar. Madagascan landscapes often contain forest fragments that represent refuges for native fauna, while also being used for firewood and timber by local human populations. As undisturbed forest becomes increasingly scarce, understanding resource competition between humans and wildlife in disturbed habitats will be increasingly important. We tested the hypothesis that Malagasy and aye-ayes (Daubentonia madagascariensis) compete for the limited number of dead trees in rainforest fragments at Tsinjoarivo, Madagascar. We surveyed 2.16 ha within five fragments (range 5-228 ha) surrounding human settlements to quantify the density of dead trees and traces of both human and aye-aye activity. Neither aye-aye nor human traces were distributed according to the availability of particular trees species, and aye-ayes and Malagasy apparently preferred several different species. Although overlap was recorded in tree species used, human use tended to be positively correlated with a species' desirability as firewood, while a negative relationship was seen for aye-ayes. Both consumers used trees of similar diameter at breast height, but those used by aye-ayes tended to be older, suggesting that human use might precede usefulness for aye-ayes. Finally, the density of dead trees and aye-aye traces were highest in smaller fragments, but human traces did not vary across fragment size. Although further study is needed to better quantify the aye-aye diet in this region, these data suggest that aye-ayes and local people compete for dead trees, and this competition could constitute a pressure on aye-aye populations.

  7. A Genome Sequence Resource for the Aye-Aye (Daubentonia madagascariensis), a Nocturnal Lemur from Madagascar

    PubMed Central

    Perry, George H.; Reeves, Darryl; Melsted, Páll; Ratan, Aakrosh; Miller, Webb; Michelini, Katelyn; Louis, Edward E.; Pritchard, Jonathan K.; Mason, Christopher E.; Gilad, Yoav

    2012-01-01

    We present a high-coverage draft genome assembly of the aye-aye (Daubentonia madagascariensis), a highly unusual nocturnal primate from Madagascar. Our assembly totals ∼3.0 billion bp (3.0 Gb), roughly the size of the human genome, comprised of ∼2.6 million scaffolds (N50 scaffold size = 13,597 bp) based on short paired-end sequencing reads. We compared the aye-aye genome sequence data with four other published primate genomes (human, chimpanzee, orangutan, and rhesus macaque) as well as with the mouse and dog genomes as nonprimate outgroups. Unexpectedly, we observed strong evidence for a relatively slow substitution rate in the aye-aye lineage compared with these and other primates. In fact, the aye-aye branch length is estimated to be ∼10% shorter than that of the human lineage, which is known for its low substitution rate. This finding may be explained, in part, by the protracted aye-aye life-history pattern, including late weaning and age of first reproduction relative to other lemurs. Additionally, the availability of this draft lemur genome sequence allowed us to polarize nucleotide and protein sequence changes to the ancestral primate lineage—a critical period in primate evolution, for which the relevant fossil record is sparse. Finally, we identified 293,800 high-confidence single nucleotide polymorphisms in the donor individual for our aye-aye genome sequence, a captive-born individual from two wild-born parents. The resulting heterozygosity estimate of 0.051% is the lowest of any primate studied to date, which is understandable considering the aye-aye's extensive home-range size and relatively low population densities. Yet this level of genetic diversity also suggests that conservation efforts benefiting this unusual species should be prioritized, especially in the face of the accelerating degradation and fragmentation of Madagascar's forests. PMID:22155688

  8. Landscape attributes driving avian influenza virus circulation in the Lake Alaotra region of Madagascar.

    PubMed

    Guerrini, Laure; Paul, Mathilde C; Leger, Lucas; Andriamanivo, Harentsoaniaina R; Maminiaina, Olivier F; Jourdan, Marion; Molia, Sophie; Rakotondravao, René; Chevalier, Véronique

    2014-05-01

    While the spatial pattern of the highly pathogenic avian influenza H5N1 virus has been studied throughout Southeast Asia, little is known on the spatial risk factors for avian influenza in Africa. In the present paper, we combined serological data from poultry and remotely sensed environmental factors in the Lake Alaotra region of Madagascar to explore for any association between avian influenza and landscape variables. Serological data from cross-sectional surveys carried out on poultry in 2008 and 2009 were examined together with a Landsat 7 satellite image analysed using supervised classification. The dominant landscape features in a 1-km buffer around farmhouses and distance to the closest water body were extracted. A total of 1,038 individual bird blood samples emanating from 241 flocks were analysed, and the association between avian influenza seroprevalence and these landcape variables was quantified using logistic regression models. No evidence of the presence of H5 or H7 avian influenza subtypes was found, suggesting that only low pathogenic avian influenza (LPAI) circulated. Three predominant land cover classes were identified around the poultry farms: grassland savannah, rice paddy fields and wetlands. A significant negative relationship was found between LPAI seroprevalence and distance to the closest body of water. We also found that LPAI seroprevalence was higher in farms characterised by predominant wetlands or rice landscapes than in those surrounded by dry savannah. Results from this study suggest that if highly pathogenic avian influenza H5N1 virus were introduced in Madagascar, the environmental conditions that prevail in Lake Alaotra region may allow the virus to spread and persist.

  9. Population Genetic Structure and Isolation by Distance of Helicobacter pylori in Senegal and Madagascar

    PubMed Central

    Linz, Bodo; Vololonantenainab, Clairette Romaine Raharisolo; Seck, Abdoulaye; Carod, Jean-François; Dia, Daouda; Garin, Benoit; Ramanampamonjy, Rado Manitrala; Thiberge, Jean-Michel; Raymond, Josette; Breurec, Sebastien

    2014-01-01

    Helicobacter pylori has probably infected the human stomach since our origins and subsequently diversified in parallel with their human hosts. The genetic population history of H. pylori can therefore be used as a marker for human migration. We analysed seven housekeeping gene sequences of H. pylori strains isolated from 78 Senegalese and 24 Malagasy patients and compared them with the sequences of strains from other geographical locations. H. pylori from Senegal and Madagascar can be placed in the previously described HpAfrica1 genetic population, subpopulations hspWAfrica and hspSAfrica, respectively. These 2 subpopulations correspond to the distribution of Niger-Congo speakers in West and most of subequatorial Africa (due to Bantu migrations), respectively. H. pylori appears as a single population in Senegal, indicating a long common history between ethnicities as well as frequent local admixtures. The lack of differentiation between these isolates and an increasing genetic differentiation with geographical distance between sampling locations in Africa was evidence for genetic isolation by distance. The Austronesian expansion that started from Taiwan 5000 years ago dispersed one of the 10 subgroups of the Austronesian language family via insular Southeast Asia into the Pacific and Madagascar, and hspMaori is a marker for the entire Austronesian expansion. Strain competition and replacement of hspMaori by hpAfrica1 strains from Bantu migrants are the probable reasons for the presence of hspSAfrica strains in Malagasy of Southeast Asian descent. hpAfrica1 strains appear to be generalist strains that have the necessary genetic diversity to efficiently colonise a wide host spectrum. PMID:24498084

  10. Population genetic structure and isolation by distance of Helicobacter pylori in Senegal and Madagascar.

    PubMed

    Linz, Bodo; Vololonantenainab, Clairette Romaine Raharisolo; Seck, Abdoulaye; Carod, Jean-François; Dia, Daouda; Garin, Benoit; Ramanampamonjy, Rado Manitrala; Thiberge, Jean-Michel; Raymond, Josette; Breurec, Sebastien

    2014-01-01

    Helicobacter pylori has probably infected the human stomach since our origins and subsequently diversified in parallel with their human hosts. The genetic population history of H. pylori can therefore be used as a marker for human migration. We analysed seven housekeeping gene sequences of H. pylori strains isolated from 78 Senegalese and 24 Malagasy patients and compared them with the sequences of strains from other geographical locations. H. pylori from Senegal and Madagascar can be placed in the previously described HpAfrica1 genetic population, subpopulations hspWAfrica and hspSAfrica, respectively. These 2 subpopulations correspond to the distribution of Niger-Congo speakers in West and most of subequatorial Africa (due to Bantu migrations), respectively. H. pylori appears as a single population in Senegal, indicating a long common history between ethnicities as well as frequent local admixtures. The lack of differentiation between these isolates and an increasing genetic differentiation with geographical distance between sampling locations in Africa was evidence for genetic isolation by distance. The Austronesian expansion that started from Taiwan 5000 years ago dispersed one of the 10 subgroups of the Austronesian language family via insular Southeast Asia into the Pacific and Madagascar, and hspMaori is a marker for the entire Austronesian expansion. Strain competition and replacement of hspMaori by hpAfrica1 strains from Bantu migrants are the probable reasons for the presence of hspSAfrica strains in Malagasy of Southeast Asian descent. hpAfrica1 strains appear to be generalist strains that have the necessary genetic diversity to efficiently colonise a wide host spectrum.

  11. Melt-bearing shear zones: analogue experiments and comparison with examples from southern Madagascar

    NASA Astrophysics Data System (ADS)

    Grujic, Djordje; Mancktelow, Neil S.

    1998-06-01

    Analogue model experiments were conducted to investigate the influence of irregularly distributed weak sites in localising strain, as an aid to understanding shear zone development in partially molten rocks. The very weak inclusions consisted of Vaseline in a homogeneous matrix of paraffin wax, which has a power-law viscous rheology. Boundary conditions were those of pure shear at constant natural strain rate and confining stress σ3. The inclusions were initially perfect cylinders with axes parallel to the intermediate bulk strain axis Y. Conjugate shear zones nucleate on the inclusions and link up to form an anastomosing pattern of high strain zones of concentrated shear surrounding much more weakly deformed pods of near coaxial strain. The zones initiate at angles near 45° to the bulk shortening axis Z but stretch and rotate towards the X axis with increasing bulk strain. All inclusions nucleate shear zones, so that with increasing development of the anastomosing pattern, weak material occurs only within the high strain zones. The restriction of migmatite leucosomes to shear zones in natural examples could also reflect a corresponding control of melt on the sites of shear zone nucleation, rather than implying accumulation from the surrounding wall-rock. The model geometry is very similar to that observed in small-scale shear zones in migmatites of southern Madagascar. Elongate zones rich in weak inclusions, originally either perpendicular or at 45° to the Z axis, were also modelled for direct comparison with the regional-scale geometry of the Pan-African high-grade 'shear zones' on Madagascar.

  12. Madagascar Highland erosion: What can we learn from the archive precipitation data?

    NASA Astrophysics Data System (ADS)

    Imola Szabó, Amanda; Raveloson, Andrea; Székely, Balázs

    2014-05-01

    In Madagascar, soil erosion is significant even when it is compared to world averages, resulting in special geomorphic forms known as lavakas appearing in the Highland regions of the island. The development of these features is due to rather unique multifactorial environmental conditions. Among many factors (geology, soil composition, human influence, etc.) the spatial and temporal distribution of precipitation is a key factor. The presence of the dry and wet season seems to be responsible for the enhanced generation of small cracks that might eventually lead to the development of a gully. However, the way of the development of such gully erosions are unknown. To what extent of the actual precipitation pattern to what extent the weather contributes to the aforementioned phenomenon has not yet been studied in great detail. The aim of our research is to study the climatic and weather conditions of lavaka-prone areas for the last decades. The typical cyclonal pattern affects the Madagascar Highlands in various ways. The precipitation and the soil moisture data show that the spatial distribution can be correlated with the appearance of lavakas to a given extent, however the local distribution cannot be explained only based on the precipitation pattern. The severity of the wet season varies strongly in the various decades leading to different precipitation maxima in January-March period. In general the effectiveness of the gully erosion is thought to be highly enhanced if the run-off of the area show large temporal variations. According to our studies this variability is quite high in certain seasons, and, despite of the low spatial resolution, related to the lavaka-prone areas. However, neither the amount of the precipitation, nor the variability alone cannot explain the high variation found in the spatial density and length distribution. Further multidisciplinary studies are necessary to draw conclusions about lavaka formation and describe the process of lavaka

  13. Forest management devolution: gap between technicians' design and villagers' practices in Madagascar.

    PubMed

    Rives, Fanny; Carrière, Stéphanie M; Montagne, Pierre; Aubert, Sigrid; Sibelet, Nicole

    2013-10-01

    In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems.

  14. Immune responses to plague infection in wild Rattus rattus, in Madagascar: a role in foci persistence?

    PubMed

    Andrianaivoarimanana, Voahangy; Telfer, Sandra; Rajerison, Minoarisoa; Ranjalahy, Michel A; Andriamiarimanana, Fehivola; Rahaingosoamamitiana, Corinne; Rahalison, Lila; Jambou, Ronan

    2012-01-01

    Plague is endemic within the central highlands of Madagascar, where its main reservoir is the black rat, Rattus rattus. Typically this species is considered susceptible to plague, rapidly dying after infection inducing the spread of infected fleas and, therefore, dissemination of the disease to humans. However, persistence of transmission foci in the same area from year to year, supposes mechanisms of maintenance among which rat immune responses could play a major role. Immunity against plague and subsequent rat survival could play an important role in the stabilization of the foci. In this study, we aimed to investigate serological responses to plague in wild black rats from endemic areas of Madagascar. In addition, we evaluate the use of a recently developed rapid serological diagnostic test to investigate the immune response of potential reservoir hosts in plague foci. We experimentally infected wild rats with Yersinia pestis to investigate short and long-term antibody responses. Anti-F1 IgM and IgG were detected to evaluate this antibody response. High levels of anti-F1 IgM and IgG were found in rats one and three weeks respectively after challenge, with responses greatly differing between villages. Plateau in anti-F1 IgM and IgG responses were reached for as few as 500 and 1500 colony forming units (cfu) inoculated respectively. More than 10% of rats were able to maintain anti-F1 responses for more than one year. This anti-F1 response was conveniently followed using dipsticks. Inoculation of very few bacteria is sufficient to induce high immune response in wild rats, allowing their survival after infection. A great heterogeneity of rat immune responses was found within and between villages which could heavily impact on plague epidemiology. In addition, results indicate that, in the field, anti-F1 dipsticks are efficient to investigate plague outbreaks several months after transmission.

  15. Immune Responses to Plague Infection in Wild Rattus rattus, in Madagascar: A Role in Foci Persistence?

    PubMed Central

    Andrianaivoarimanana, Voahangy; Telfer, Sandra; Rajerison, Minoarisoa; Ranjalahy, Michel A.; Andriamiarimanana, Fehivola; Rahaingosoamamitiana, Corinne; Rahalison, Lila; Jambou, Ronan

    2012-01-01

    Background Plague is endemic within the central highlands of Madagascar, where its main reservoir is the black rat, Rattus rattus. Typically this species is considered susceptible to plague, rapidly dying after infection inducing the spread of infected fleas and, therefore, dissemination of the disease to humans. However, persistence of transmission foci in the same area from year to year, supposes mechanisms of maintenance among which rat immune responses could play a major role. Immunity against plague and subsequent rat survival could play an important role in the stabilization of the foci. In this study, we aimed to investigate serological responses to plague in wild black rats from endemic areas of Madagascar. In addition, we evaluate the use of a recently developed rapid serological diagnostic test to investigate the immune response of potential reservoir hosts in plague foci. Methodology/Principal Findings We experimentally infected wild rats with Yersinia pestis to investigate short and long-term antibody responses. Anti-F1 IgM and IgG were detected to evaluate this antibody response. High levels of anti-F1 IgM and IgG were found in rats one and three weeks respectively after challenge, with responses greatly differing between villages. Plateau in anti-F1 IgM and IgG responses were reached for as few as 500 and 1500 colony forming units (cfu) inoculated respectively. More than 10% of rats were able to maintain anti-F1 responses for more than one year. This anti-F1 response was conveniently followed using dipsticks. Conclusion/Significance Inoculation of very few bacteria is sufficient to induce high immune response in wild rats, allowing their survival after infection. A great heterogeneity of rat immune responses was found within and between villages which could heavily impact on plague epidemiology. In addition, results indicate that, in the field, anti-F1 dipsticks are efficient to investigate plague outbreaks several months after transmission. PMID

  16. Randomised controlled trial of alternative male and female condom promotion strategies targeting sex workers in Madagascar

    PubMed Central

    Hoke, Theresa H; Feldblum, Paul J; Van Damme, Kathleen; Nasution, Marlina D; Grey, Thomas W; Wong, Emelita L; Ralimamonjy, Louisette; Raharimalala, Leonardine; Rasamindrakotroka, Andry

    2007-01-01

    Objectives To assess whether individual clinic‐based counselling as a supplement to peer education for male and female condom promotion leads to greater use of protection and lower STI prevalence among sex workers in Madagascar already exposed to intensive male condom promotion. Methods In two public dispensaries in Madagascar, a total of 901 sex workers were randomly allocated between two alternative male and female condom promotion interventions: peer education only, or peer education supplemented with individual clinic‐based counselling. Participants were followed for 12 months. Every 2 months they made clinic visits, where they were interviewed on condom use. Peer educators counselled all participants on condom use as they accompanied their assigned participants to study visits. Participants assigned to receive the supplemental intervention were counselled by a trained clinician following study interviews. Participants were tested and treated for chlamydia, gonorrhoea and trichomoniasis every 6 months. We used logistic regression to assess whether the more intensive intervention was associated with reduced STI prevalence. Use of protection with clients and non‐paying partners was assessed by study arm, site, and visit. Results There was no statistically significant association between study arm and aggregated STI prevalence. No substantial differences in levels of reported protection were noted between study groups. Conclusions This study found little evidence for gains from more thorough clinical counselling on male and female condom use. These findings suggest that less clinically intensive interventions such as peer education could be suitable for male and female condom promotion in populations already exposed to barrier method promotion. PMID:17591662

  17. Crustal structure of southern Madagascar from receiver functions and ambient noise correlation: Implications for crustal evolution

    NASA Astrophysics Data System (ADS)

    Rindraharisaona, E. J.; Tilmann, F.; Yuan, X.; Rümpker, G.; Giese, J.; Rambolamanana, G.; Barruol, G.

    2017-02-01

    The Precambrian rocks of Madagascar were formed and/or modified during continental collision known as the Pan-African orogeny. Aborted Permo-Triassic Karoo rifting and the subsequent separation from Africa and India resulted in the formation of sedimentary basins in the west and volcanic activity predominantly along the margins. Many geological studies have documented the imprint of these processes, but little was known about the deeper structure. We therefore deployed seismic stations along an SE-NW trending profile spanning nearly all geological domains of southern Madagascar. Here we focus on the crustal structure, which we determined based on joint analysis of receiver functions and surface waves derived from ambient noise measurements. For the sedimentary basin we document a thinning of the underlying crystalline basement by up to ˜60% to 13 km. The crustal velocity structure demonstrates that the thinning was accomplished by removal or exhumation of the lower crust. Both the Proterozoic and Archean crust have a 10 km thick upper crust and 10-12 km thick midcrust. However, in contrast to the typical structure of Proterozoic and Archean aged crust, the Archean lower crust is thicker and faster than the Proterozoic one, indicating possible magmatic intrusions; an underplated layer of 2-8 km thickness is present only below the Archean crust. The Proterozoic mafic lower crust might have been lost during continental collision by delamination or subduction or thinned as a result of extensional collapse. Finally, the Cretaceous volcanics along the east coast are characterized by thin crust (30 km) and very large VP/VS ratios.

  18. Early-warning health and process indicators for sentinel surveillance in Madagascar 2007-2011

    PubMed Central

    Rajatonirina, Soatiana; Rakotomanana, Fanjasoa; Randrianasolo, Laurence; Razanajatovo, Norosoa Harline; Andriamandimby, Soa Fy; Ravolomanana, Lisette; Randrianarivo-Solofoniaina, Armand Eugène; Reynes, Jean-Marc; Piola, Patrice; Finlay-Vickers, Alyssa; Heraud, Jean-Michel; Richard, Vincent

    2014-01-01

    Background: Epidemics pose major threats in resource-poor countries, and surveillance tools for their early detection and response are often inadequate. In 2007, a sentinel surveillance system was established in Madagascar, with the aim of rapidly identifying potential epidemics of febrile or diarrhoeal syndromes and issuing alerts. We present the health and process indicators for the five years during which this system was constructed, showing the spatiotemporal trends, early-warning sign detection capability and process evaluation through timely analyses of high-quality data. Methods: The Malagasy sentinel surveillance network is currently based on data for fever and diarrhoeal syndromes collected from 34 primary health centres and reported daily via the transmission of short messages from mobile telephones. Data are analysed daily at the Institut Pasteur de Madagascar to make it possible to issue alerts more rapidly, and integrated process indicators (timeliness, data quality) are used to monitor the system. Results: From 2007 to 2011, 917,798 visits were reported. Febrile syndromes accounted for about 11% of visits annually, but the trends observed differed between years and sentinel sites. From 2007 to 2011, 21 epidemic alerts were confirmed. However, delays in data transmission were observed (88% transmitted within 24 hours in 2008; 67% in 2011) and the percentage of forms transmitted each week for validity control decreased from 99.9% in 2007 to 63.5% in 2011. Conclusion: A sentinel surveillance scheme should take into account both epidemiological and process indicators. It must also be governed by the main purpose of the surveillance and by local factors, such as the motivation of healthcare workers and telecommunication infrastructure. Permanent evaluation indicators are required for regular improvement of the system. PMID:25598869

  19. Early-warning health and process indicators for sentinel surveillance in Madagascar 2007-2011.

    PubMed

    Rajatonirina, Soatiana; Rakotomanana, Fanjasoa; Randrianasolo, Laurence; Razanajatovo, Norosoa Harline; Andriamandimby, Soa Fy; Ravolomanana, Lisette; Randrianarivo-Solofoniaina, Armand Eugène; Reynes, Jean-Marc; Piola, Patrice; Finlay-Vickers, Alyssa; Heraud, Jean-Michel; Richard, Vincent

    2014-01-01

    Epidemics pose major threats in resource-poor countries, and surveillance tools for their early detection and response are often inadequate. In 2007, a sentinel surveillance system was established in Madagascar, with the aim of rapidly identifying potential epidemics of febrile or diarrhoeal syndromes and issuing alerts. We present the health and process indicators for the five years during which this system was constructed, showing the spatiotemporal trends, early-warning sign detection capability and process evaluation through timely analyses of high-quality data. The Malagasy sentinel surveillance network is currently based on data for fever and diarrhoeal syndromes collected from 34 primary health centres and reported daily via the transmission of short messages from mobile telephones. Data are analysed daily at the Institut Pasteur de Madagascar to make it possible to issue alerts more rapidly, and integrated process indicators (timeliness, data quality) are used to monitor the system. From 2007 to 2011, 917,798 visits were reported. Febrile syndromes accounted for about 11% of visits annually, but the trends observed differed between years and sentinel sites. From 2007 to 2011, 21 epidemic alerts were confirmed. However, delays in data transmission were observed (88% transmitted within 24 hours in 2008; 67% in 2011) and the percentage of forms transmitted each week for validity control decreased from 99.9% in 2007 to 63.5% in 2011. A sentinel surveillance scheme should take into account both epidemiological and process indicators. It must also be governed by the main purpose of the surveillance and by local factors, such as the motivation of healthcare workers and telecommunication infrastructure. Permanent evaluation indicators are required for regular improvement of the system.

  20. Health-related challenges in United States Peace Corps Volunteers serving for two years in Madagascar.

    PubMed

    Leutscher, Peter D C; Bagley, Sandra W

    2003-01-01

    The United States Peace Corps has nearly 8000 Volunteers (PCVs) working in more than 70 countries, predominantly in the developing part of the world. The volunteers are challenged by many new and unfamiliar health problems, as a result of change in living conditions during their service. The goal of this study was to assess the health problems of PCVs in Madagascar, and to use this information to evaluate the effectiveness of the current PCV health support program. PCVs, finalizing their 2 years of service, were enrolled in the study. Data were retrieved from individual Peace Corps service medical records, the close of service (COS) physical evaluation, and a PCV questionnaire, which elicited additional self-reported health problems and concerns. Sixty-nine PCVs took part in the study. Median age at COS was 24 years (95% CI 23-26 years), and the male/female ratio was 1 : 3.6 (15 males and 54 females). Skin, gastrointestinal and respiratory infections constituted the three most common reported health problems. Among the registered parasitic infections were ova and parasites in the stool (42.0%), confirmed and presumptive malaria (15.9%) and schistosomiasis (11.6%). Female PCVs more frequently reported dermatologic manifestations than male PCVs: postadolescent acne (48.2% vs. 13.3%) and telogen hair loss (33.3% vs. 6.7%). Amenorrhea, as the most commonly reported menstrual alteration during service, was reported by 15 (27.7%) female PCVs. The PCVs in Madagascar encounter a broad range of health-related problems, most of which are preventable infectious diseases. Reinforcement of the preservice personal health-training curriculum later during service is needed. Reported dermatologic and menstrual disturbances in female subjects may be associated with stress-related estrogen imbalance. More studies are warranted to assess the stress impact of long-term travel on the female physiology.

  1. Anthropophilic mosquitoes and malaria transmission in the eastern foothills of the central highlands of Madagascar.

    PubMed

    Andrianaivolambo, Lala; Domarle, Olivier; Randrianarivelojosia, Milijaona; Ratovonjato, Jocelyn; Le Goff, Gilbert; Talman, Arthur; Ariey, Frédéric; Robert, Vincent

    2010-12-01

    Malaria remains a major public health problem in Madagascar, as it is the first cause of morbidity in health care facilities. Its transmission remains poorly documented. An entomological study was carried out over 1 year (October 2003-September 2004) in Saharevo, a village located at an altitude of 900m on the eastern edge of the Malagasy central highlands. Mosquitoes were sampled weekly upon landing on human volunteers and in various resting-places. Out of 5515 mosquitoes collected on humans, 3219 (58.4%) were anophelines. Eleven anopheline species were represented, among which Anopheles funestus, Anopheles gambiae, Anopheles arabiensis and Anopheles mascarensis. Out of 677 mosquitoes collected in bedrooms by pyrethrum spray catches and in Muirhead-Thomson pits, 656 (96.9%) were anopheline belonging to these four latter species. The proportion of mosquitoes that fed on human varied according to the resting-places and the mosquito species: 86% of An. funestus resting in bedrooms fed on humans, whereas only 16% of An. funestus and 0% of An. mascarensis resting in pits fed on humans. The proportion of anopheline mosquitoes infected with human Plasmodium was measured by circumsporozoite protein-ELISA: 10/633 An. funestus (1.58%), 1/211 An. gambiae s.l. (0.48%) and 2/268 An. mascarensis (0.75%). The annual entomological inoculation rate (number of bites of infected anophelines per adult) was estimated at 2.78. The transmission was mainly due to An. funestus and only observed in the second half of the rainy season, from February to May. These results are discussed in the context of the current malaria vector control policy in Madagascar.

  2. The origin and dispersion of human parasitic diseases in the old world (Africa, Europe and Madagascar).

    PubMed

    Nozais, Jean-Pierre

    2003-01-01

    The ancestors of present-day man (Homo sapiens sapiens) appeared in East Africa some three and a half million years ago (Australopithecs), and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade) led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae) were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase) which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani--the dog--has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa) and dromadary (in the Sahara and North Africa). Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before reaching Madagascar

  3. Implementation and evaluation of a curriculum to teach reproductive health to adolescents in northern Madagascar.

    PubMed

    Klinger, Amanda; Asgary, Ramin

    2016-05-01

    In Madagascar, prevalence of sexually transmitted infections (STIs) and unplanned pregnancies are high among adolescents. Limited reproductive health education is available. In northern Madagascar, in 2014, we assessed the baseline knowledge, attitudes and self-efficacy regarding STIs/HIV and family planning among 155 adolescents, and designed and implemented a 6-week reproductive health curriculum for adolescents using complementary teaching methods. We evaluated the curriculum through pre- and post-curriculum surveys of adolescents using paired t-tests. Pre-test survey revealed a general lack of knowledge regarding different types of STIs. Post-curriculum, there was a significant improvement in the following educational domains: general knowledge of HIV/AIDS, other STIs and family planning (49%±17% to 65%±15%) (p<0.001), self-efficacy and use of contraceptives (57%±26% to 70%±26%) (p<0.01), and the overall combined scores of knowledge, attitude and self-efficacy (53%±14% to 68%±14%) (p<0.001). Open-ended questions revealed significant misconceptions and stigma regarding oral and anal sex and usage of condoms. Important misconceptions and knowledge gaps regarding reproductive health exist among adolescents. The comprehensive reproductive health curriculum with complementary teaching methods was feasible, well-received and effective, and could be considered for integration into the schools' curricula. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Forest Management Devolution: Gap Between Technicians' Design and Villagers' Practices in Madagascar

    NASA Astrophysics Data System (ADS)

    Rives, Fanny; Carrière, Stéphanie M.; Montagne, Pierre; Aubert, Sigrid; Sibelet, Nicole

    2013-10-01

    In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems.

  5. The value of small size: loss of forest patches and ecological thresholds in southern Madagascar.

    PubMed

    Bodin, Orjan; Tengö, Maria; Norman, Anna; Lundberg, Jakob; Elmqvist, Thomas

    2006-04-01

    Many services generated by forest ecosystems provide essential support for human well-being. However, the vulnerability of these services to environmental change such as forest fragmentation are still poorly understood. We present spatial modeling of the generation of ecosystem services in a human-dominated landscape where forest habitat patches, protected by local taboos, are located in a matrix of cultivated land in southern Madagascar. Two ecosystem services dependent on the forest habitats were addressed: (1) crop pollination services by wild and semidomesticated bees (Apoidea), essential for local crop production of, for example, beans, and (2) seed dispersal services based on the presence of ring-tailed lemurs (Lemur catta). We studied the vulnerability of these ecosystem services to a plausible scenario of successive destruction of the smallest habitat patches. Our results indicate that, in spite of the fragmented nature of the landscape, the fraction of the landscape presently covered by both crop pollination and seed dispersal services is surprisingly high. It seems that the taboo system, though indirectly and unintentionally, contributes to upholding the generation of these services by protecting the forest patches. Both services are, however, predicted to be very vulnerable to the successive removal of small patches. For crop pollination, the rate of decrease in cover was significant even when only the smallest habitat patches were removed. The capacity for seed dispersal across the landscape displayed several thresholds with habitat patch removal. Our results suggest that, in order to maintain capacity for seed dispersal across the landscape and crop pollination cover in southern Androy, the geographical location of the remaining forest patches is more crucial than their size. We argue that in heavily fragmented production landscapes, small forest patches should increasingly be viewed as essential for maintaining ecosystem services, such as agricultural

  6. Review of the genus Saprinus Erichson, 1834 from Madagascar and adjacent islands with description of a new species (Coleoptera: Histeridae: Saprininae) Third contribution to the knowledge of the Histeridae of Madagascar.

    PubMed

    Lackner, Tomáš; Gomy, Yves

    2016-02-19

    Clown beetles belonging to the genus Saprinus Erichson, 1834 from Madagascar and adjacent islands are reviewed. The Malagasy fauna of Saprinus consists of seven species: Saprinus (Saprinus) erichsonii Marseul, 1855; Saprinus (Saprinus) fulgidicollis Marseul, 1855; Saprinus (Saprinus) basalis Fairmaire, 1898; Saprinus (Saprinus) cupreus Erichson, 1834; Saprinus (Saprinus) chalcites (Illiger, 1807); Saprinus (Saprinus) splendens (Paykull, 1811); one species S. (Saprinus) labordei sp. nov., is described as new. Saprinus erichsonii Marseul, 1855 is transferred from the subgenus Phaonius Reichardt, 1941 into the nominotypical subgenus based on the morphological evidence. Lectotypes of the following species are designated: Saprinus erichsonii Marseul, 1855; Saprinus basalis Fairmaire, 1898 and Saprinus fulgidicollis Marseul, 1855. Saprinus (Saprinus) cupreus Erichson, 1834 is newly reported from Madagascar and Saprinus (Saprinus) basalis Fairmaire, 1898 is newly reported from the following countries: Congo, Gambia, Central African Republic, Namibia, Zimbabwe and Republic of South Africa.

  7. Tracing Arab-Islamic inheritance in Madagascar: study of the Y-chromosome and mitochondrial DNA in the Antemoro.

    PubMed

    Capredon, Mélanie; Brucato, Nicolas; Tonasso, Laure; Choesmel-Cadamuro, Valérie; Ricaut, François-Xavier; Razafindrazaka, Harilanto; Rakotondrabe, Andriamihaja Bakomalala; Ratolojanahary, Mamisoa Adelta; Randriamarolaza, Louis-Paul; Champion, Bernard; Dugoujon, Jean-Michel

    2013-01-01

    Madagascar is located at the crossroads of the Asian and African worlds and is therefore of particular interest for studies on human population migration. Within the large human diversity of the Great Island, we focused our study on a particular ethnic group, the Antemoro. Their culture presents an important Arab-Islamic influence, but the question of an Arab biological inheritance remains unresolved. We analyzed paternal (n=129) and maternal (n=135) lineages of this ethnic group. Although the majority of Antemoro genetic ancestry comes from sub-Saharan African and Southeast Asian gene pools, we observed in their paternal lineages two specific haplogroups (J1 and T1) linked to Middle Eastern origins. This inheritance was restricted to some Antemoro sub-groups. Statistical analyses tended to confirm significant Middle Eastern genetic contribution. This study gives a new perspective to the large human genetic diversity in Madagascar.

  8. Filling the Gondwana gaps: new species and new reports of Beatogordius Heinze, 1934 (Nematomorpha) from Australia and Madagascar.

    PubMed

    Schmidt-Rhaesa, Andreas; Bryant, Malcom S

    2004-03-01

    We describe two new species of Beatogordius Heinze, 1934 (Nematomorpha), B. australiensis and B. lineatus, from Queensland, Australia. One further species, B. abbreviatus (Villot, 1874), which was known from Reunion, is reported from Madagascar. These new reports extend the range of Beatogordius from Africa and South America to include Madagascar and Australia. Beatogordius was likely distributed over the Gondwana continent prior to the separation of continental plates in the Mesozoic. This extends the existence of the taxon Nematomorpha, which was only known from young brown coal and amber, into the Mesozoic. Adhesive warts, structures anterior of the cloacal opening in males of B. abbreviatus, were originally described as characteristic structures of Gordionus Müller, 1927, but their occurrence in B. abbreviatus and one South American species indicates a wider distribution of this character.

  9. Tracing Arab-Islamic Inheritance in Madagascar: Study of the Y-chromosome and Mitochondrial DNA in the Antemoro

    PubMed Central

    Capredon, Mélanie; Brucato, Nicolas; Tonasso, Laure; Choesmel-Cadamuro, Valérie; Ricaut, François-Xavier; Razafindrazaka, Harilanto; Rakotondrabe, Andriamihaja Bakomalala; Ratolojanahary, Mamisoa Adelta; Randriamarolaza, Louis-Paul; Champion, Bernard; Dugoujon, Jean-Michel

    2013-01-01

    Madagascar is located at the crossroads of the Asian and African worlds and is therefore of particular interest for studies on human population migration. Within the large human diversity of the Great Island, we focused our study on a particular ethnic group, the Antemoro. Their culture presents an important Arab-Islamic influence, but the question of an Arab biological inheritance remains unresolved. We analyzed paternal (n=129) and maternal (n=135) lineages of this ethnic group. Although the majority of Antemoro genetic ancestry comes from sub-Saharan African and Southeast Asian gene pools, we observed in their paternal lineages two specific haplogroups (J1 and T1) linked to Middle Eastern origins. This inheritance was restricted to some Antemoro sub-groups. Statistical analyses tended to confirm significant Middle Eastern genetic contribution. This study gives a new perspective to the large human genetic diversity in Madagascar. PMID:24278350

  10. [How much does a caesarean section cost in Madagascar? Socio-economical aspects and caesarean sections rate in Toamasina, Madagascar 1999-2001].

    PubMed

    Robitail, S; Gorde, S; Barrau, K; Tremouille, S; Belec, M

    2004-11-01

    The maternal mortality is a major issue of public health in developing countries. Essential obstetric cares, especially caesarean section, play a crucial role in the decrease of maternal mortality. WHO, FNUAP and UNICEF estimate that the minimum acceptable rate of caesarean section in developing countries must reach 5% to guarantee safety for both the new-born and the mother. In Madagascar; the average national rate of caesarean section was 0.6% in 1997. In the area of Toamasina, this rate was 0.7%. To increase the number of women who can access to those essential obstetric cares, several solutions may be followed. One of them is to develop health insurance for pregnant women. This kind of solution seems to be well accepted and equitable. To reach this goal, this study was carried out to define sociodemographic characteristics of women who got caesarean section in Toamasina, to assess the cost of a caesarean section at the CHR (regional hospital) of Toamasina, and to measure the evolution of the caesarean section rate in the area. A retrospective survey was carried out for the years 1999, 2000 and 2001 including all women who got a caesarean section in the area of Toamasina: in the hospital of Toamasina and in the one of Fenerive-Est. Data were collected in both hospitals. 748 women were included in the survey The cost-analysis consisted in a partial medico-economic cost analysis which was measured from the patient's point of view. Sociodemographic characteristics are comparable with the results found in the literature. The mean age of the women involved was 28+/-7 years. The main indications for caesarean section were foeto-pelvic disproportion (37%) and placenta praevia (12%). The maternal mortality rate was 3%. The rate of infantile mortality was 18%. The cover rate of caesarean section in the area of the CHR is estimated respectively at 0.58%, 0.67% and 0.71% for the years 1999, 2000 and 2001. Data collection step was very difficult to carry out. The rates of

  11. Rapid Response to Evaluate the Presence of Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis) and Ranavirus in Wild Amphibian Populations in Madagascar

    PubMed Central

    Kolby, Jonathan E.; Smith, Kristine M.; Ramirez, Sara D.; Rabemananjara, Falitiana; Pessier, Allan P.; Brunner, Jesse L.; Goldberg, Caren S.; Berger, Lee; Skerratt, Lee F.

    2015-01-01

    We performed a rapid response investigation to evaluate the presence and distribution of amphibian pathogens in Madagascar following our identification of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranavirus in commercially exported amphibians. This targeted risk-based field surveillance program was conducted from February to April 2014 encompassing 12 regions and 47 survey sites. We simultaneously collected amphibian and environmental samples to increase survey sensitivity and performed sampling both in wilderness areas and commercial amphibian trade facilities. Bd was not detected in any of 508 amphibian skin swabs or 68 water filter samples, suggesting pathogen prevalence was below 0.8%, with 95% confidence during our visit. Ranavirus was detected in 5 of 97 amphibians, including one adult Mantidactylus cowanii and three unidentified larvae from Ranomafana National Park, and one adult Mantidactylus mocquardi from Ankaratra. Ranavirus was also detected in water samples collected from two commercial amphibian export facilities. We also provide the first report of an amphibian mass-mortality event observed in wild amphibians in Madagascar. Although neither Bd nor ranavirus appeared widespread in Madagascar during this investigation, additional health surveys are required to disentangle potential seasonal variations in pathogen abundance and detectability from actual changes in pathogen distribution and rates of spread. Accordingly, our results should be conservatively interpreted until a comparable survey effort during winter months has been performed. It is imperative that biosecurity practices be immediately adopted to limit the unintentional increased spread of disease through the movement of contaminated equipment or direct disposal of contaminated material from wildlife trade facilities. The presence of potentially introduced strains of ranaviruses suggests that Madagascar's reptile species might also be threatened by disease

  12. New species and distribution records of selenopid spiders of the genus Hovops Benoit in Madagascar (Araneae, Selenopidae).

    PubMed

    Artigas, Sandra Mónica Rodriguez; Corronca, Jose Antonio

    2014-03-24

    Hovops Benoit is a heterogeneous genus of selenopid spiders that was prior to this study represented by seven species that are endemic to Madagascar. Here, we describe four new species: H. antakarana sp. n. (♀), H. ikongo sp. n. (♀), H. menabe sp. n. (♀), and H. vezo sp. n. (♀). A map of the new species is provided as well as new records on two of the known species H. pusillus (Simon, 1897) and H. legrasi (Simon, 1887).

  13. Systematics of the Madagascar Anelosimus spiders: remarkable local richness and endemism, and dual colonization from the Americas.

    PubMed

    Agnarsson, Ingi; Jencik, Brian B; Veve, Giselle M; Hanitriniaina, Sahondra; Agostini, Diego; Goh, Seok Ping; Pruitt, Jonathan; Kuntner, Matjaž

    2015-01-01

    Despite the alarming rates of deforestation and forest fragmentation, Madagascar still harbors extraordinary biodiversity. However, in many arthropod groups, such as spiders, this biodiversity remains mostly unexplored and undescribed. The first subsocial Madagascan species of the theridiid spider genus Anelosimus were described in 2005 when six new species were found to coexist in the Périnet forest fragment within Andasibe-Mantadia NP. However, this discovery was based only on a few specimens and the extent of this Madagascan radiation has remained unknown. We here report on a thorough survey of >350 colonies from Périnet, and three pilot surveys into additional Madagascar forests (Ambohitantely, Ranamofana, and Montagne d'Ambre). The morphological, molecular and natural history data from these surveys facilitated a revised taxonomy and phylogenetic hypothesis of Madagascan Anelosimus. This subsocial clade currently comprises six previously known (Anelosimusandasibe Agnarsson & Kuntner, 2005, Anelosimusmay Agnarsson, 2005, Anelosimusnazariani Agnarsson & Kuntner, 2005, Anelosimussallee Agnarsson & Kuntner, 2005, Anelosimussalut Agnarsson & Kuntner, 2005, Anelosimusvondrona Agnarsson & Kuntner, 2005) and 10 new species: Anelosimusata sp. n., Anelosimusbuffoni sp. n., Anelosimusdarwini sp. n., Anelosimushookeri sp. n., Anelosimushuxleyi sp. n., Anelosimuslamarcki sp. n., Anelosimusmoramora sp. n., Anelosimustita sp. n., Anelosimustorfi sp. n., Anelosimuswallacei sp. n.. With the exception of Anelosimusmay and Anelosimusvondrona, all other species appear to be single forest endemics. While additional sampling is necessary, these data imply a much higher local richness and endemism in Madagascan forests than in any other comparable area globally. The phylogenetic results establish a sister clade relationship between the subsocial Anelosimus in Madagascar and the American 'eximius group', and between the solitary Anelosimusdecaryi on Madagascar and a solitary

  14. Phylogeography in Response to Reproductive Strategies and Ecogeographic Isolation in Ant Species on Madagascar: Genus Mystrium (Formicidae: Amblyoponinae)

    PubMed Central

    Graham, Natalie R.; Fisher, Brian L.; Girman, Derek J.

    2016-01-01

    The bulk of models used to understand the species diversification on Madagascar have been constructed using vertebrate taxa. It is not clear how these models affect less vagile species that may interact at a variety of spatial scales. Several studies on vertebrates have divided Madagascar into east-west bioclimatic regions, suggesting there is a fundamental division between eastern wet-adapted and western dry-adapted taxa. An alternative model of ecogeographic constraints shows a north-south division. We test whether the diversification in a small arthropod with variable degrees of dispersal conform to either model of ecogeographic constraints proposed for vertebrate taxa. We employ a molecular taxonomic dataset using ~2 kilobases nuDNA (Wg, LW Rh, Abd-A, 28s) and 790 basepairs mtDNA (CO1), along with geographic and habitat data, to examine the diversification patterns of the ant genus Mystrium Roger, 1862, (Subfamily Amblyoponinae) from Madagascar. The nuclear and mitochondrial phylogenies were both congruent with morphospecies as indicated in a recent revision of the genus. Species of Mystrium practice different colony reproductive strategies (winged queens vs non-winged queens). Alternate reproductive strategies led to inequalities in female dispersal ability among species, providing an additional layer for examination of the impacts of vagility on divergence, especially when measured using a maternally inherited locus. Mystrium species distribution patterns support these models of ecogeographic constraints. Reproductive strategy effected how Mystrium mtDNA lineages were associated with large-scale habitat distinctions and various topographical features. Furthermore, in some cases we find microgeographic population structure which appears to have been impacted by localized habitat differences (tsingy limestone formations, littoral forest) on a scale much smaller than that found in vertebrates. The current system offers a finer scale look at species

  15. Nesogordonia tricarpellata (Dombeyaceae), a new species from Madagascar that compels modification of the morphological circumscription of the genus

    PubMed Central

    Skema, Cynthia; Dorr, Laurence J.

    2011-01-01

    Abstract Nesogordonia tricarpellata Skema & Dorr, sp. nov., a new species from southeastern Madagascar, is described and illustrated. It differs from all other species of Nesogordonia Baill. in having 6–9 stamens, 3 staminodes, a 3-carpellate ovary, and a 3-valved capsule. These androecial and gynoecial characters require modification of the long-standing circumscription of the genus. The new species also has the southernmost geographic range of any species in the genus. PMID:22171171

  16. Systematics of the Madagascar Anelosimus spiders: remarkable local richness and endemism, and dual colonization from the Americas

    PubMed Central

    Agnarsson, Ingi; Jencik, Brian B.; Veve, Giselle M.; Hanitriniaina, Sahondra; Agostini, Diego; Goh, Seok Ping; Pruitt, Jonathan; Kuntner, Matjaž

    2015-01-01

    Abstract Despite the alarming rates of deforestation and forest fragmentation, Madagascar still harbors extraordinary biodiversity. However, in many arthropod groups, such as spiders, this biodiversity remains mostly unexplored and undescribed. The first subsocial Madagascan species of the theridiid spider genus Anelosimus were described in 2005 when six new species were found to coexist in the Périnet forest fragment within Andasibe-Mantadia NP. However, this discovery was based only on a few specimens and the extent of this Madagascan radiation has remained unknown. We here report on a thorough survey of >350 colonies from Périnet, and three pilot surveys into additional Madagascar forests (Ambohitantely, Ranamofana, and Montagne d’Ambre). The morphological, molecular and natural history data from these surveys facilitated a revised taxonomy and phylogenetic hypothesis of Madagascan Anelosimus. This subsocial clade currently comprises six previously known (Anelosimus andasibe Agnarsson & Kuntner, 2005, Anelosimus may Agnarsson, 2005, Anelosimus nazariani Agnarsson & Kuntner, 2005, Anelosimus sallee Agnarsson & Kuntner, 2005, Anelosimus salut Agnarsson & Kuntner, 2005, Anelosimus vondrona Agnarsson & Kuntner, 2005) and 10 new species: Anelosimus ata sp. n., Anelosimus buffoni sp. n., Anelosimus darwini sp. n., Anelosimus hookeri sp. n., Anelosimus huxleyi sp. n., Anelosimus lamarcki sp. n., Anelosimus moramora sp. n., Anelosimus tita sp. n., Anelosimus torfi sp. n., Anelosimus wallacei sp. n.. With the exception of Anelosimus may and Anelosimus vondrona, all other species appear to be single forest endemics. While additional sampling is necessary, these data imply a much higher local richness and endemism in Madagascan forests than in any other comparable area globally. The phylogenetic results establish a sister clade relationship between the subsocial Anelosimus in Madagascar and the American ‘eximius group’, and between the solitary Anelosimus decaryi

  17. Planthopper (Hemiptera: Flatidae) parasitized by larval erythraeid mite (Trombidiformes: Erythraeidae)-a description of two new species from western Madagascar.

    PubMed

    Mąkol, Joanna; Moniuszko, Hanna; Swierczewski, Dariusz; Stroiński, Adam

    2014-01-01

    Descriptions of Dambullaeus adonis Mąkol et Moniuszko SP NOV: (Trombidiformes: Erythraeidae, Callidosomatinae) and Latois nigrolineata Świerczewski et Stroiński SP NOV: (Hemiptera: Fulgoromorpha, Flatidae) from Madagascar are provided. The first host record for ectoparasitic larvae of Dambullaeus Haitlinger, 2001 and the first evidence on host-parasite association between flatid adult and erythraeid larvae are given. Genus Dambullaeus, known exclusively from larvae and now comprising two species of Gondwanan distribution, is critically reappraised.

  18. High Prevalence of West Nile Virus in Domestic Birds and Detection in 2 New Mosquito Species in Madagascar

    PubMed Central

    Rakotoharinome, Vincent Michel; Ravaomanana, Julie; Tantely, Michael Luciano; Heraud, Jean-Michel; Cardinale, Eric

    2016-01-01

    West Nile virus is an arthropod-borne zoonosis transmitted by a large number of mosquito species, and birds play a key role as reservoir of the virus. Its distribution is largely widespread over Africa, Asia, the Americas and Europe. Since 1978, it has frequently been reported in Madagascar. Studies described a high seroprevalence level of the virus in humans in different areas of the island and a human fatal case of WNV infection was reported in 2011. Despite these reports, the epidemiology of WNV in Madagascar, in particular, viral circulation remains unclear. To explore the transmission of WNV in two rural human populations of Madagascar, we investigated local mosquitoes and poultry for evidence of current infections, and determined seroprevalence of candidate sentinel species among the local poultry. These 2 areas are close to lakes where domestic birds, migratory wild birds and humans coexist. Serological analysis revealed WNV antibodies in domestic birds (duck, chicken, goose, turkey and guinea fowl) sampled in both districts (Antsalova 29.4% and Mitsinjo 16.7%). West Nile virus nucleic acid was detected in one chicken and in 8 pools of mosquitoes including 2 mosquito species (Aedeomyia madagascarica and Anopheles pauliani) that have not been previously described as candidate vectors for WNV. Molecular analysis of WNV isolates showed that all viruses detected were part of the lineage 2 that is mainly distributed in Africa, and were most closely matched by the previous Malagasy strains isolated in 1988. Our study showed that WNV circulates in Madagascar amongst domestic birds and mosquitoes, and highlights the utility of poultry as a surveillance tool to detect WNV transmission in a peri-domestic setting. PMID:26807720

  19. Prevalence of chronic hepatitis B virus infection and infrastructure for its diagnosis in Madagascar: implication for the WHO's elimination strategy.

    PubMed

    Andriamandimby, Soa Fy; Olive, Marie-Marie; Shimakawa, Yusuke; Rakotomanana, Fanjasoa; Razanajatovo, Iony Manitra; Andrianinarivomanana, Tsarasoa Malala; Ravalohery, Jean-Pierre; Andriamamonjy, Seta; Rogier, Christophe; Héraud, Jean-Michel

    2017-08-04

    WHO developed a global strategy to eliminate hepatitis B by 2030 and set target to treat 80% of people with chronic hepatitis B virus (HBV) infection eligible for antiviral treatment. As a first step to achieve this goal, it is essential to conduct a situation analysis that is fundamental to designing national hepatitis plans. We therefore estimated the prevalence of chronic HBV infection, and described the existing infrastructure for HBV diagnosis in Madagascar. We conducted a stratified multi-stage serosurvey of hepatitis B surface antigen (HBsAg) in adults aged ≥18 years using 28 sentinel surveillance sites located throughout the country. We obtained the list of facilities performing HBV testing from the Ministry of Health, and contacted the person responsible at each facility. A total of 1778 adults were recruited from the 28 study areas. The overall weighted seroprevalence of HBsAg was 6.9% (95% CI: 5.6-8.6). Populations with a low socio-economic status and those living in rural areas had a significantly higher seroprevalence of HBsAg. The ratio of facilities equipped to perform HBsAg tests per 100,000 inhabitants was 1.02 in the capital city of Antananarivo and 0.21 outside the capital. There were no facilities with the capacity to perform HBV DNA testing or transient elastography to measure liver fibrosis. There are only five hepatologists in Madagascar. Madagascar has a high-intermediate level of endemicity for HBV infection with a severely limited capacity for its diagnosis and treatment. Higher HBsAg prevalence in rural or underprivileged populations underlines the importance of a public health approach to decentralize the management of chronic HBV carriers in Madagascar by using simple and low-cost diagnostic tools.

  20. High Prevalence of West Nile Virus in Domestic Birds and Detection in 2 New Mosquito Species in Madagascar.

    PubMed

    Maquart, Marianne; Boyer, Sébastien; Rakotoharinome, Vincent Michel; Ravaomanana, Julie; Tantely, Michael Luciano; Heraud, Jean-Michel; Cardinale, Eric

    2016-01-01

    West Nile virus is an arthropod-borne zoonosis transmitted by a large number of mosquito species, and birds play a key role as reservoir of the virus. Its distribution is largely widespread over Africa, Asia, the Americas and Europe. Since 1978, it has frequently been reported in Madagascar. Studies described a high seroprevalence level of the virus in humans in different areas of the island and a human fatal case of WNV infection was reported in 2011. Despite these reports, the epidemiology of WNV in Madagascar, in particular, viral circulation remains unclear. To explore the transmission of WNV in two rural human populations of Madagascar, we investigated local mosquitoes and poultry for evidence of current infections, and determined seroprevalence of candidate sentinel species among the local poultry. These 2 areas are close to lakes where domestic birds, migratory wild birds and humans coexist. Serological analysis revealed WNV antibodies in domestic birds (duck, chicken, goose, turkey and guinea fowl) sampled in both districts (Antsalova 29.4% and Mitsinjo 16.7%). West Nile virus nucleic acid was detected in one chicken and in 8 pools of mosquitoes including 2 mosquito species (Aedeomyia madagascarica and Anopheles pauliani) that have not been previously described as candidate vectors for WNV. Molecular analysis of WNV isolates showed that all viruses detected were part of the lineage 2 that is mainly distributed in Africa, and were most closely matched by the previous Malagasy strains isolated in 1988. Our study showed that WNV circulates in Madagascar amongst domestic birds and mosquitoes, and highlights the utility of poultry as a surveillance tool to detect WNV transmission in a peri-domestic setting.

  1. Rapid Response to Evaluate the Presence of Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis) and Ranavirus in Wild Amphibian Populations in Madagascar.

    PubMed

    Kolby, Jonathan E; Smith, Kristine M; Ramirez, Sara D; Rabemananjara, Falitiana; Pessier, Allan P; Brunner, Jesse L; Goldberg, Caren S; Berger, Lee; Skerratt, Lee F

    2015-01-01

    We performed a rapid response investigation to evaluate the presence and distribution of amphibian pathogens in Madagascar following our identification of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranavirus in commercially exported amphibians. This targeted risk-based field surveillance program was conducted from February to April 2014 encompassing 12 regions and 47 survey sites. We simultaneously collected amphibian and environmental samples to increase survey sensitivity and performed sampling both in wilderness areas and commercial amphibian trade facilities. Bd was not detected in any of 508 amphibian skin swabs or 68 water filter samples, suggesting pathogen prevalence was below 0.8%, with 95% confidence during our visit. Ranavirus was detected in 5 of 97 amphibians, including one adult Mantidactylus cowanii and three unidentified larvae from Ranomafana National Park, and one adult Mantidactylus mocquardi from Ankaratra. Ranavirus was also detected in water samples collected from two commercial amphibian export facilities. We also provide the first report of an amphibian mass-mortality event observed in wild amphibians in Madagascar. Although neither Bd nor ranavirus appeared widespread in Madagascar during this investigation, additional health surveys are required to disentangle potential seasonal variations in pathogen abundance and detectability from actual changes in pathogen distribution and rates of spread. Accordingly, our results should be conservatively interpreted until a comparable survey effort during winter months has been performed. It is imperative that biosecurity practices be immediately adopted to limit the unintentional increased spread of disease through the movement of contaminated equipment or direct disposal of contaminated material from wildlife trade facilities. The presence of potentially introduced strains of ranaviruses suggests that Madagascar's reptile species might also be threatened by disease

  2. Seismic anisotropy of the lithosphere and asthenosphere beneath southern Madagascar from teleseismic shear wave splitting analysis and waveform modeling

    NASA Astrophysics Data System (ADS)

    Reiss, M. C.; Rümpker, G.; Tilmann, F.; Yuan, X.; Giese, J.; Rindraharisaona, E. J.

    2016-09-01

    Madagascar occupies a key position in the assembly and breakup of the supercontinent Gondwana. It has been used in numerous geological studies to reconstruct its original position within Gondwana and to derive plate kinematics. Seismological observations in Madagascar to date have been sparse. Using a temporary, dense seismic profile across southern Madagascar, we present the first published study of seismic anisotropy from shear wave splitting analyses of teleseismic phases. The splitting parameters obtained show significant small-scale variation of fast polarization directions and delay times across the profile, with fast polarization rotating from NW in the center to NE in the east and west of the profile. The delay times range between 0.4 and 1.5 s. A joint inversion of waveforms at each station is applied to derive hypothetical one-layer splitting parameters. We use finite-difference, full-waveform modeling to test several hypotheses about the origin and extent of seismic anisotropy. Our observations can be explained by asthenospheric anisotropy with a fast polarization direction of 50°, approximately parallel to the absolute plate motion direction, in combination with blocks of crustal anisotropy. Predictions of seismic anisotropy as inferred from global mantle flow models or global anisotropic surface wave tomography are not in agreement with the observations. Small-scale variations of splitting parameters require significant crustal anisotropy. Considering the complex geology of Madagascar, we interpret the change in fast-axis directions as a 150 km wide zone of ductile deformation in the crust as a result of the intense reworking of lithospheric material during the Pan-African orogeny. This fossil anisotropic pattern is underlain by asthenospheric anisotropy induced by plate motion.

  3. Phylogeography in Response to Reproductive Strategies and Ecogeographic Isolation in Ant Species on Madagascar: Genus Mystrium (Formicidae: Amblyoponinae).

    PubMed

    Graham, Natalie R; Fisher, Brian L; Girman, Derek J

    2016-01-01

    The bulk of models used to understand the species diversification on Madagascar have been constructed using vertebrate taxa. It is not clear how these models affect less vagile species that may interact at a variety of spatial scales. Several studies on vertebrates have divided Madagascar into east-west bioclimatic regions, suggesting there is a fundamental division between eastern wet-adapted and western dry-adapted taxa. An alternative model of ecogeographic constraints shows a north-south division. We test whether the diversification in a small arthropod with variable degrees of dispersal conform to either model of ecogeographic constraints proposed for vertebrate taxa. We employ a molecular taxonomic dataset using ~2 kilobases nuDNA (Wg, LW Rh, Abd-A, 28s) and 790 basepairs mtDNA (CO1), along with geographic and habitat data, to examine the diversification patterns of the ant genus Mystrium Roger, 1862, (Subfamily Amblyoponinae) from Madagascar. The nuclear and mitochondrial phylogenies were both congruent with morphospecies as indicated in a recent revision of the genus. Species of Mystrium practice different colony reproductive strategies (winged queens vs non-winged queens). Alternate reproductive strategies led to inequalities in female dispersal ability among species, providing an additional layer for examination of the impacts of vagility on divergence, especially when measured using a maternally inherited locus. Mystrium species distribution patterns support these models of ecogeographic constraints. Reproductive strategy effected how Mystrium mtDNA lineages were associated with large-scale habitat distinctions and various topographical features. Furthermore, in some cases we find microgeographic population structure which appears to have been impacted by localized habitat differences (tsingy limestone formations, littoral forest) on a scale much smaller than that found in vertebrates. The current system offers a finer scale look at species

  4. Does Diversity Matter In Modeling? Testing A New Version Of The FORMIX3 Growth Model For Madagascar Rainforests

    NASA Astrophysics Data System (ADS)

    Armstrong, A. H.; Fischer, R.; Shugart, H. H.; Huth, A.

    2012-12-01

    Ecological forecasting has become an essential tool used by ecologists to understand the dynamics of growth and disturbance response in threatened ecosystems such as the rainforests of Madagascar. In the species rich tropics, forest conservation is often eclipsed by anthropogenic factors, resulting in a heightened need for accurate assessment of biomass before these ecosystems disappear. The objective of this study was to test a new Madagascar rainforest specific version of the FORMIX3 growth model (Huth and Ditzer, 2000; Huth et al 1998) to assess how accurately biomass can be simulated in high biodiversity forests using a method of functional type aggregation in an individual-based model framework. Rainforest survey data collected over three growing seasons, including 265 tree species, was aggregated into 12 plant functional types based on size and light requirements. Findings indicated that the forest study site compared best when the simulated forest reached mature successional status. Multiple level comparisons between model simulation data and survey plot data found that though some features, such as the dominance of canopy emergent species and relative absence of small woody treelets are captured by the model, other forest attributes were not well reflected. Overall, the ability to accurately simulate the Madagascar rainforest was slightly diminished by the aggregation of tree species into size and light requirement functional type groupings.

  5. Hibernation in the pygmy slow loris (Nycticebus pygmaeus): multiday torpor in primates is not restricted to Madagascar.

    PubMed

    Ruf, Thomas; Streicher, Ulrike; Stalder, Gabrielle L; Nadler, Tilo; Walzer, Chris

    2015-12-03

    Hibernation and short daily torpor are states of energy conservation with reduced metabolism and body temperature. Both hibernation, also called multiday torpor, and daily torpor are common among mammals and occur in at least 11 orders. Within the primates, there is a peculiar situation, because to date torpor has been almost exclusively reported for Malagasy lemurs. The single exception is the African lesser bushbaby, which is capable of daily torpor, but uses it only under extremely adverse conditions. For true hibernation, the geographical restriction was absolute. No primate outside of Madagascar was previously known to hibernate. Since hibernation is commonly viewed as an ancient, plesiomorphic trait, theoretically this could mean that hibernation as an overwintering strategy was lost in all other primates in mainland Africa, Asia, and the Americas. However, we hypothesized that a good candidate species for the use of hibernation, outside of Madagascar should be the pygmy slow loris (Nycticebus pygmaeus), a small primate inhabiting tropical forests. Here, we show that pygmy slow lorises exposed to natural climatic conditions in northern Vietnam during winter indeed undergo torpor lasting up to 63 h, that is, hibernation. Thus, hibernation has been retained in at least one primate outside of Madagascar.

  6. Reconstruction of Rift Valley fever transmission dynamics in Madagascar: estimation of force of infection from seroprevalence surveys using Bayesian modelling

    PubMed Central

    Olive, Marie-Marie; Grosbois, Vladimir; Tran, Annelise; Nomenjanahary, Lalaina Arivony; Rakotoarinoro, Mihaja; Andriamandimby, Soa-Fy; Rogier, Christophe; Heraud, Jean-Michel; Chevalier, Veronique

    2017-01-01

    The force of infection (FOI) is one of the key parameters describing the dynamics of transmission of vector-borne diseases. Following the occurrence of two major outbreaks of Rift Valley fever (RVF) in Madagascar in 1990–91 and 2008–09, recent studies suggest that the pattern of RVF virus (RVFV) transmission differed among the four main eco-regions (East, Highlands, North-West and South-West). Using Bayesian hierarchical models fitted to serological data from cattle of known age collected during two surveys (2008 and 2014), we estimated RVF FOI and described its variations over time and space in Madagascar. We show that the patterns of RVFV transmission strongly differed among the eco-regions. In the North-West and Highlands regions, these patterns were synchronous with a high intensity in mid-2007/mid-2008. In the East and South-West, the peaks of transmission were later, between mid-2008 and mid-2010. In the warm and humid northwestern eco-region favorable to mosquito populations, RVFV is probably transmitted all year-long at low-level during inter-epizootic period allowing its maintenance and being regularly introduced in the Highlands through ruminant trade. The RVF surveillance of animals of the northwestern region could be used as an early warning indicator of an increased risk of RVF outbreak in Madagascar. PMID:28051125

  7. The evolution of local endemism in madagascar: watershed versus climatic gradient hypotheses evaluated by null biogeographic models.

    PubMed

    Pearson, Richard G; Raxworthy, Christopher J

    2009-04-01

    Substantial insular speciation has resulted in exceptionally high levels of endemism in Madagascar, creating locally restricted species' ranges that remain poorly understood. The contributions of alternative processes that could influence patterns of local endemism-including speciation by geographic isolation or adaptation to environmental gradients-are widely debated, both for Madagascar and elsewhere. A recently proposed hypothesis (the "watershed hypothesis") suggests that allopatric speciation driven by isolation in watersheds during Quaternary climate shifts provides a general explanation for patterns of local endemism across taxa in Madagascar. Here we tested coincidence between species' distributions and areas of endemism predicted by two contrasting biogeographic hypotheses: (1) the watershed hypothesis, and (2) an alternative hypothesis driven by climatic gradients (the "current climate hypothesis"). Statistical significance of coincidence was assessed by comparing against a null model. Surprisingly, we found that extant distributions of lemurs, geckos, and chameleons reveal species patterns that are significantly coincident with the watershed and current climate hypotheses. These results strongly support local endemism developing from multiple processes, even among closely related species. Our findings thus indicate that pluralistic approaches will offer the best option both for understanding processes that generate local endemism, and for incorporating endemism within conservation priority setting.

  8. Hibernation in the pygmy slow loris (Nycticebus pygmaeus): multiday torpor in primates is not restricted to Madagascar

    PubMed Central

    Ruf, Thomas; Streicher, Ulrike; Stalder, Gabrielle L.; Nadler, Tilo; Walzer, Chris

    2015-01-01

    Hibernation and short daily torpor are states of energy conservation with reduced metabolism and body temperature. Both hibernation, also called multiday torpor, and daily torpor are common among mammals and occur in at least 11 orders. Within the primates, there is a peculiar situation, because to date torpor has been almost exclusively reported for Malagasy lemurs. The single exception is the African lesser bushbaby, which is capable of daily torpor, but uses it only under extremely adverse conditions. For true hibernation, the geographical restriction was absolute. No primate outside of Madagascar was previously known to hibernate. Since hibernation is commonly viewed as an ancient, plesiomorphic trait, theoretically this could mean that hibernation as an overwintering strategy was lost in all other primates in mainland Africa, Asia, and the Americas. However, we hypothesized that a good candidate species for the use of hibernation, outside of Madagascar should be the pygmy slow loris (Nycticebus pygmaeus), a small primate inhabiting tropical forests. Here, we show that pygmy slow lorises exposed to natural climatic conditions in northern Vietnam during winter indeed undergo torpor lasting up to 63 h, that is, hibernation. Thus, hibernation has been retained in at least one primate outside of Madagascar. PMID:26633602

  9. RETROSPECTIVE STUDY OF METHYLMERCURY AND OTHER METAL(LOID)S IN MADAGASCAR UNPOLISHED RICE (Oryza sativa L.)

    PubMed Central

    Rothenberg, Sarah E.; Mgutshini, Noma L.; Bizimis, Michael; Johnson-Beebout, Sarah E.; Ramanantsoanirina, Alain

    2014-01-01

    The rice ingestion rate in Madagascar is among the highest globally; however studies concerning metal(loid) concentrations in Madagascar rice are lacking. For Madagascar unpolished rice (n=51 landraces), levels of toxic elements (e.g., total mercury, methylmercury, arsenic and cadmium) as well as essential micronutrients (e.g., zinc and selenium) were uniformly low, indicating potentially both positive and negative health effects. Aside from manganese (Wilcoxon rank sum, p<0.01), no significant differences in concentrations for all trace elements were observed between rice with red bran (n=20) and brown bran (n=31) (Wilcoxon rank sum, p=0.06–0.91). Compared to all elements in rice, rubidium (i.e., tracer for phloem transport) was most positively correlated with methylmercury (Pearson's r=0.33, p<0.05) and total mercury (r=0.44, p<0.05), while strontium (i.e., tracer for xylem transport) was least correlated with total mercury and methylmercury (r<0.01 for both), suggesting inorganic mercury and methylmercury were possibly more mobile in phloem compared to xylem. PMID:25463705

  10. Stable carbon isotope values document how a Late Holocene expansion in grasslands impacted vertebrates in northwestern Madagascar

    NASA Astrophysics Data System (ADS)

    Crowley, B. E.; Samonds, K.

    2012-12-01

    Madagascar is home to some of the world's most distinctive plants and animals. Unfortunately, forest loss and habitat degradation has had a dramatic impact on both floral and faunal communities. Here we use carbon isotope values in radiocarbon-dated bones to examine how the vertebrate community at Anjohibe Cave, northwestern Madagascar, responded to a Late Holocene increase in C4 grass abundance. Our data demonstrate that major changes in the vegetation and animal community are recent phenomena at Anjohibe. Extinct lemurs and hippopotamuses were present until ca. 1500 years ago. These taxa relied exclusively on C3 resources. Locally extirpated fauna were present until 300 years ago. The majority of these species also relied on C3 resources. Their presence strongly suggests that the region surrounding the cave was more wooded than it is now, possibly as recently as 300 years ago. All introduced individuals are modern. Rats (Rattus sp.), shrews (Suncus murinus), and the giant frog Hoplobatrachus cf. tigrinus, have remarkably high carbon isotope values, implicating substantial ingestion of C4 foods. It is possible that grass abundance has increased dramatically in the past 100 years. Alternatively, opportunistically granivorous rats and shrews may selectively consume seeds from C4 grasses. In agreement with previous studies, stable isotope data reveal details of vegetation and faunal turnover in Northwestern Madagascar. Grasses have increased, forest dwelling species have vanished, and introduced taxa are exploiting a novel niche.

  11. A link between low-frequency mesoscale eddy variability around Madagascar and the large-scale Indian Ocean variability

    NASA Astrophysics Data System (ADS)

    Palastanga, V.; van Leeuwen, P. J.; de Ruijter, W. P. M.

    2006-09-01

    A connection is shown to exist between the mesoscale eddy activity around Madagascar and the large-scale interannual variability in the Indian Ocean. We use the combined TOPEX/Poseidon-ERS sea surface height (SSH) data for the period 1993-2003. The SSH-fields in the Mozambique Channel and east of Madagascar exhibit a significant interannual oscillation. This is related to the arrival of large-scale anomalies that propagate westward along 10°-15°S in response to the Indian Ocean dipole (IOD) events. Positive (negative) SSH anomalies associated to a positive (negative) IOD phase induce a shift in the intensity and position of the tropical and subtropical gyres. A weakening (strengthening) results in the intensity of the South Equatorial Current and its branches along east Madagascar. In addition, the flow through the narrows of the Mozambique Channel around 17°S increases (decreases) during periods of a stronger and northward (southward) extension of the subtropical (tropical) gyre. Interaction between the currents in the narrows and southward propagating eddies from the northern Channel leads to interannual variability in the eddy kinetic energy of the central Channel in phase with the one in the SSH-field.

  12. The Hippoboscidae (Insecta: Diptera) from Madagascar, with new records from the “Parc National de Midongy Befotaka”

    PubMed Central

    Rahola, N.; Goodman, S.M.; Robert, V.

    2011-01-01

    The Hippoboscidae or “louse-flies” is a family of pupiparous Diptera, which in their adult stage are ectoparasites of mammals and birds. This paper presents a comprehensive review of Malagasy Hippoboscidae. In total, amongst the 213 species of this family known worldwide, 14 have been reported in Madagascar, among which six are considered as endemic to the Malagasy region. In addition, data are presented from a collection of 17 Hippoboscidae obtained from seven species of forest-dwelling birds in the “Parc National de Midongy Befotaka”, southeastern Madagascar, in 2003. The flies in this collection belong to three different species: Icosta malagasii (one), Ornithoica podicipis (ten) and Ornithoctona laticornis (six). The two former species were previously only known from single specimens in museum collections; the later species is distributed across much of the Afrotropical region and the records presented herein are the first for Madagascar. All the seven bird species are new hosts for hippoboscids. We present the first description of the male of Icosta malagasii. An illustrated dichotomous determination key of the 14 Malagasy species, based on morphological criteria only, is presented. PMID:21678788

  13. Reconstruction of Rift Valley fever transmission dynamics in Madagascar: estimation of force of infection from seroprevalence surveys using Bayesian modelling.

    PubMed

    Olive, Marie-Marie; Grosbois, Vladimir; Tran, Annelise; Nomenjanahary, Lalaina Arivony; Rakotoarinoro, Mihaja; Andriamandimby, Soa-Fy; Rogier, Christophe; Heraud, Jean-Michel; Chevalier, Veronique

    2017-01-04

    The force of infection (FOI) is one of the key parameters describing the dynamics of transmission of vector-borne diseases. Following the occurrence of two major outbreaks of Rift Valley fever (RVF) in Madagascar in 1990-91 and 2008-09, recent studies suggest that the pattern of RVF virus (RVFV) transmission differed among the four main eco-regions (East, Highlands, North-West and South-West). Using Bayesian hierarchical models fitted to serological data from cattle of known age collected during two surveys (2008 and 2014), we estimated RVF FOI and described its variations over time and space in Madagascar. We show that the patterns of RVFV transmission strongly differed among the eco-regions. In the North-West and Highlands regions, these patterns were synchronous with a high intensity in mid-2007/mid-2008. In the East and South-West, the peaks of transmission were later, between mid-2008 and mid-2010. In the warm and humid northwestern eco-region favorable to mosquito populations, RVFV is probably transmitted all year-long at low-level during inter-epizootic period allowing its maintenance and being regularly introduced in the Highlands through ruminant trade. The RVF surveillance of animals of the northwestern region could be used as an early warning indicator of an increased risk of RVF outbreak in Madagascar.

  14. Most children who took part in a comprehensive malnutrition programme in Madagascar reached and maintained the recovery threshold.

    PubMed

    Magnin, Margot; Stoll, Beat; Voahangy, Rajaobelina; Jeannot, Emilien

    2017-06-01

    The benefits of including nutritional education in programmes that tackle moderate and severe acute malnutrition remain poorly documented. This study in Madagascar evaluated the nutritional status of children who took part in an innovative programme that included maternal education, on completion and after a year. Each year, this outpatient programme admits 2400 malnourished children from six months to 59 months in the lower districts of Antananarivo, Madagascar. Children were drawn by lots, and their anthropometric data were measured. A descriptive retrospective longitudinal study was conducted on 573 children who took part between 2010 and 2013. The programme lasted an average of 38 days and, on completion, 82.2% had reached the recovery threshold, and 16.2% had moved up to mild malnutrition. This was achieved with food supplements of 720 kcal per day, despite the Malagasy Public Health recommendation of 1000-1500 kcal per day. After one year, 79.1% were still above the recovery threshold, and 15% had mild malnutrition. The recovery rate was higher for children under 24 months of age (odds ratio 2.9, 95% confidence interval 1.93-4.59). Most children who attended this malnutrition programme with maternal education in Madagascar reached the recovery threshold on completion and had maintained it after one year. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  15. Molecular and serological evidence of flea-associated typhus group and spotted fever group rickettsial infections in Madagascar.

    PubMed

    Rakotonanahary, Rado J L; Harrison, Alan; Maina, Alice N; Jiang, Ju; Richards, Allen L; Rajerison, Minoarisoa; Telfer, Sandra

    2017-03-04

    Rickettsiae are obligate intracellular bacteria responsible for many febrile syndromes around the world, including in sub-Saharan Africa. Vectors of these pathogens include ticks, lice, mites and fleas. In order to assess exposure to flea-associated Rickettsia species in Madagascar, human and small mammal samples from an urban and a rural area, and their associated fleas were tested. Anti-typhus group (TGR)- and anti-spotted fever group rickettsiae (SFGR)-specific IgG were detected in 24 (39%) and 21 (34%) of 62 human serum samples, respectively, using indirect ELISAs, with six individuals seropositive for both. Only two (2%) Rattus rattus out of 86 small mammals presented antibodies against TGR. Out of 117 fleas collected from small mammals, Rickettsia typhi, a TGR, was detected in 26 Xenopsylla cheopis (24%) collected from rodents of an urban area (n = 107), while two of these urban X. cheopis (2%) were positive for Rickettsia felis, a SFGR. R. felis DNA was also detected in eight (31%) out of 26 Pulex irritans fleas. The general population in Madagascar are exposed to rickettsiae, and two flea-associated Rickettsia pathogens, R. typhi and R. felis, are present near or in homes. Although our results are from a single district, they demonstrate that rickettsiae should be considered as potential agents of undifferentiated fever in Madagascar.

  16. Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.).

    PubMed

    Rothenberg, Sarah E; Mgutshini, Nomathamsanqa L; Bizimis, Michael; Johnson-Beebout, Sarah E; Ramanantsoanirina, Alain

    2015-01-01

    The rice ingestion rate in Madagascar is among the highest globally; however studies concerning metal(loid) concentrations in Madagascar rice are lacking. For Madagascar unpolished rice (n = 51 landraces), levels of toxic elements (e.g., total mercury, methylmercury, arsenic and cadmium) as well as essential micronutrients (e.g., zinc and selenium) were uniformly low, indicating potentially both positive and negative health effects. Aside from manganese (Wilcoxon rank sum, p < 0.01), no significant differences in concentrations for all trace elements were observed between rice with red bran (n = 20)and brown bran (n = 31) (Wilcoxon rank sum, p = 0.06-0.91). Compared to all elements in rice,rubidium (i.e., tracer for phloem transport) was most positively correlated with methylmercury (Pearson'sr = 0.33, p < 0.05) and total mercury (r = 0.44, p < 0.05), while strontium (i.e., tracer for xylemtransport) was least correlated with total mercury and methylmercury (r < 0.01 for both), suggesting inorganic mercury and methylmercury were possibly more mobile in phloem compared to xylem.

  17. How to use local resources to fight malnutrition in Madagascar? A study combining a survey and a consumer test.

    PubMed

    Ramaroson Rakotosamimanana, Vonimihaingo; Valentin, Dominique; Arvisenet, Gaëlle

    2015-12-01

    This study aimed to understand consumers' habits and belief structures concerning local food products and to develop a new snack as a way to fight against children malnutrition in Madagascar. A large variety of natural food resources grow in Madagascar, like Moringa oleifera (MO) which leaves are rich in nutrients but not consumed. First, a survey conducted in four areas of Madagascar revealed that MO leaves are known for their health benefits but infrequently consumed, probably because of their low satiating power and strong odor. In the studied areas, different levels of consumption were observed, which may be linked to varying levels of familiarity with MO by the local populations, this in turn resulting from different situations regarding geographical and historical availability. In contrary, resources such as cassava are perceived as having negative effects on health but are widely consumed because they are cheap, liked by children and satiating. The second step in the study aimed to propose products that could increase MO consumption without completely changing food practices. The acceptability of snacks associating cassava roots and MO was evaluated by means of hedonic tests performed by children. Between the snacks tested, the preferred snack contained the highest quantity of MO and was sweetened. There was no effect of area on the acceptance of the formulated snacks. This work is an evaluation of the potential of MO in the diet of malnourished population.

  18. Genetic evidence for Rift Valley fever outbreaks in Madagascar resulting from virus introductions from the East African mainland rather than enzootic maintenance.

    PubMed

    Carroll, Serena A; Reynes, Jean-Marc; Khristova, Marina L; Andriamandimby, Soa Fy; Rollin, Pierre E; Nichol, Stuart T

    2011-07-01

    Rift Valley fever virus (RVFV), a mosquito-borne phlebovirus, has been detected in Madagascar since 1979, with occasional outbreaks. In 2008 to 2009, a large RVFV outbreak was detected in Malagasy livestock and humans during two successive rainy seasons. To determine whether cases were due to enzootic maintenance of the virus within Madagascar or to importation from the East African mainland, nine RVFV whole genomic sequences were generated for viruses from the 1991 and 2008 Malagasy outbreaks. Bayesian coalescent analyses of available whole S, M, and L segment sequences were used to estimate the time to the most recent common ancestor for the RVFVs. The 1979 Madagascar isolate shared a common ancestor with strains on the mainland around 1972. The 1991 Madagascar isolates were in a clade distinct from that of the 1979 isolate and shared a common ancestor around 1987. Finally, the 2008 Madagascar viruses were embedded within a large clade of RVFVs from the 2006-2007 outbreak in East Africa and shared a common ancestor around 2003 to 2004. These results suggest that the most recent Madagascar outbreak was caused by a virus likely arriving in the country some time between 2003 and 2008 and that this outbreak may be an extension of the 2006-2007 East African outbreak. Clustering of the Malagasy sequences into subclades indicates that the viruses have continued to evolve during their short-term circulation within the country. These data are consistent with the notion that RVFV outbreaks in Madagascar result not from emergence from enzootic cycles within the country but from recurrent virus introductions from the East African mainland.

  19. Deforestation and Rice: Using Methods in Modeling and Remote Sensing to Project Patterns of Forest Change in Eastern Madagascar

    NASA Astrophysics Data System (ADS)

    Armstrong, A. H.; Fatoyinbo, T. E.; Fischer, R.; Huth, A.; Shugart, H. H.

    2013-12-01

    In the species rich tropics, forest conservation is often eclipsed by anthropogenic disturbance, resulting in a heightened need for an accurate assessment of biomass and the gaining of predictive capability before these ecosystems disappear. The combination of multi-temporal remote sensing data, field data and forest growth modeling to quantify carbon stocks and flux is therefore of great importance. In this study, we utilize these methods to (1) improve forest biomass and carbon flux estimates for the study region in Eastern Madagascar, and (2) initialize an individual-based growth model that incorporates the anthropogenic factors causing deforestation to project ecosystem response to future environmental change. Recent studies have shown that there is a direct correlation between the international rice market and rates of deforestation in tropical countries such as Madagascar (see Minten et al., 2006). Further, although law protects the remaining forest areas, dictatorships and recent political unrest have lead to poor or non-existent enforcement of precious wood and forest protection over the past 35 years. Our approach combined multi-temporal remote sensing analysis and ecological modeling using a theoretical and mathematical approach to assess biomass change and to understand how tree growth and life history (growth response patterns) relate to past and present economic variability in Madagascar forests of the eastern Toamasina region. We measured rates of change of deforestation with respect to politics and the price of rice by classifying and comparing biomass using 30m Landsat during 5 political regime time periods (1985-1992, 1993-1996, 1997-2001, 2002-2008, 2009 to present). Forest biomass estimations were calibrated using forest inventory data collected over 3 growing seasons over the study region (130 small circular plots in primary forest). This information was then built into the previously parameterized (Armstrong et al., in prep and Fischer et al in

  20. “Tazomoka Is Not a Problem”. Local Perspectives on Malaria, Fever Case Management and Bed Net Use in Madagascar

    PubMed Central

    Raboanary, Emma; Kesteman, Thomas; Piola, Patrice; Randrianarivelojosia, Milijaona; Rogier, Christophe

    2016-01-01

    Background Although its incidence has been decreasing during the last decade, malaria is still a major public health issue in Madagascar. The use of Long Lasting Insecticidal Nets (LLIN) remains a key malaria control intervention strategy in Madagascar, however, it encounters some obstacles. The present study aimed to explore the local terminology related to malaria, information channels about malaria, attitude towards bed nets, and health care seeking practices in case of fever. This article presents novel qualitative findings about malaria. Until now, no such data has been published for Madagascar. Methods A comparative qualitative study was carried out at four sites in Madagascar, each differing by malaria epidemiology and socio-cultural background of the populations. Seventy-one semi-structured interviews were conducted with biomedical and traditional caregivers, and members of the local population. In addition, observations of the living conditions and the uses of bed net were conducted. Results Due to the differences between local and biomedical perspectives on malaria, official messages did not have the expected impact on population in terms of prevention and care seeking behaviors. Rather, most information retained about malaria was spread through informal information circulation channels. Most interviewees perceived malaria as a disease that is simple to treat. Tazomoka (“mosquito fever”), the Malagasy biomedical word for malaria, was not used by populations. Tazo (“fever”) and tazomahery (“strong fever”) were the terms more commonly used by members of the local population to refer to malaria related symptoms. According to local perceptions in all areas, tazo and tazomahery were not caused by mosquitos. Each of these symptoms required specific health recourse. The usual fever management strategies consisted of self-medication or recourse to traditional and biomedical caregivers. Usage of bed nets was intermittent and was not directly linked to

  1. Estimating Herd Immunity to Amphibian Chytridiomycosis in Madagascar Based on the Defensive Function of Amphibian Skin Bacteria.

    PubMed

    Bletz, Molly C; Myers, Jillian; Woodhams, Douglas C; Rabemananjara, Falitiana C E; Rakotonirina, Angela; Weldon, Che; Edmonds, Devin; Vences, Miguel; Harris, Reid N

    2017-01-01

    For decades, Amphibians have been globally threatened by the still expanding infectious disease, chytridiomycosis. Madagascar is an amphibian biodiversity hotspot where Batrachochytrium dendrobatidis (Bd) has only recently been detected. While no Bd-associated population declines have been reported, the risk of declines is high when invasive virulent lineages become involved. Cutaneous bacteria contribute to host innate immunity by providing defense against pathogens for numerous animals, including amphibians. Little is known, however, about the cutaneous bacterial residents of Malagasy amphibians and the functional capacity they have against Bd. We cultured 3179 skin bacterial isolates from over 90 frog species across Madagascar, identified them via Sanger sequencing of approximately 700 bp of the 16S rRNA gene, and characterized their functional capacity against Bd. A subset of isolates was also tested against multiple Bd genotypes. In addition, we applied the concept of herd immunity to estimate Bd-associated risk for amphibian communities across Madagascar based on bacterial antifungal activity. We found that multiple bacterial isolates (39% of all isolates) cultured from the skin of Malagasy frogs were able to inhibit Bd. Mean inhibition was weakly correlated with bacterial phylogeny, and certain taxonomic groups appear to have a high proportion of inhibitory isolates, such as the Enterobacteriaceae, Pseudomonadaceae, and Xanthamonadaceae (84, 80, and 75% respectively). Functional capacity of bacteria against Bd varied among Bd genotypes; however, there were some bacteria that showed broad spectrum inhibition against all tested Bd genotypes, suggesting that these bacteria would be good candidates for probiotic therapies. We estimated Bd-associated risk for sampled amphibian communities based on the concept of herd immunity. Multiple amphibian communities, including those in the amphibian diversity hotspots, Andasibe and Ranomafana, were estimated to be below

  2. "Tazomoka Is Not a Problem". Local Perspectives on Malaria, Fever Case Management and Bed Net Use in Madagascar.

    PubMed

    Mattern, Chiarella; Pourette, Dolorès; Raboanary, Emma; Kesteman, Thomas; Piola, Patrice; Randrianarivelojosia, Milijaona; Rogier, Christophe

    2016-01-01

    Although its incidence has been decreasing during the last decade, malaria is still a major public health issue in Madagascar. The use of Long Lasting Insecticidal Nets (LLIN) remains a key malaria control intervention strategy in Madagascar, however, it encounters some obstacles. The present study aimed to explore the local terminology related to malaria, information channels about malaria, attitude towards bed nets, and health care seeking practices in case of fever. This article presents novel qualitative findings about malaria. Until now, no such data has been published for Madagascar. A comparative qualitative study was carried out at four sites in Madagascar, each differing by malaria epidemiology and socio-cultural background of the populations. Seventy-one semi-structured interviews were conducted with biomedical and traditional caregivers, and members of the local population. In addition, observations of the living conditions and the uses of bed net were conducted. Due to the differences between local and biomedical perspectives on malaria, official messages did not have the expected impact on population in terms of prevention and care seeking behaviors. Rather, most information retained about malaria was spread through informal information circulation channels. Most interviewees perceived malaria as a disease that is simple to treat. Tazomoka ("mosquito fever"), the Malagasy biomedical word for malaria, was not used by populations. Tazo ("fever") and tazomahery ("strong fever") were the terms more commonly used by members of the local population to refer to malaria related symptoms. According to local perceptions in all areas, tazo and tazomahery were not caused by mosquitos. Each of these symptoms required specific health recourse. The usual fever management strategies consisted of self-medication or recourse to traditional and biomedical caregivers. Usage of bed nets was intermittent and was not directly linked to protection against malaria in the eyes

  3. Preparer une firme-reseau dans le transport routier des hydrocarbures le cas de TOTAL Madagascar

    NASA Astrophysics Data System (ADS)

    Razakamanifidiny, Patrick Dany

    2009-12-01

    In a dynamic context, a network firm is more and more suggested in scientific writings as a prevalent strategy to develop several firms in subcontracting link in order to satisfy the needs of their customers asking for products which are complex to manufacture. However, due to lack of sufficient preparation, most of network organizations fail. That's why it seems legitimate to explore an avenue of research on the preparation step of a network firm. How a third intermediary can develop and try out a change process in order to stimulate the commitment of films to organize themselves in network? This study is developed inside the framework of an intervention-research applied to the case of the oil distribution company TOTAL Madagascar. 71 weeks of intervention actions carried out with 27 subcontracting firms of hydrocarbon road transport located to Antananarivo are recorded within this framework. One of the critical elements in the oil distribution in Madagascar is the scarcity of the subcontracting firms of hydrocarbon road transport which are able to meet the required quality criterions. A lack of management standards observed in several small and medium enterprises of hydrocarbon road transport, a growth of the number of tankers accidents, and an insufficiency of individual resources to develop competences constitute the main reasons which explain this scarcity. By this way, a preparation step of a network firm was developed in order to increase the management competences of the subcontracting firms of hydrocarbon road transport, and to develop their capacity of collective learning. This step comes from the evolutionary perspective which consists in elaborating and implementing uprooting, movement and rooting activities related to a change implementation model taking reactions of the participating enterprises into consideration, through a change understanding process from objection to exploration until engagement. The realization of theses activities had been

  4. Sedimentological features of lateritic and saprolitic horizons in a mid-slope lavaka, Central Highlands, Madagascar

    NASA Astrophysics Data System (ADS)

    Udvardi, B.; Raveloson, A.; Visnovitz, F.; Szabó, Cs.; Kovács, I.; Székely, B.

    2012-04-01

    Madagascar is characterized by a world-record erosion rate, especially in the Central Highlands and the vicinity of Lake Alaotra. As a consequence of the high erosion rate several specific erosional landforms develop in the area. Among them an inverted teardrop-shaped geomorphic feature, the lavaka, meaning 'hole' in Malagasy, is very typical in the hilly landscape. These unique features are widespread in Madagascar though somewhat similar patterns can also be found in Congo, South Africa and Brazil. In these areas, material from the lavakas is washed down from the hillsides into the streams and rivers after every heavy rain (1500-1800 mm/yr). The high sediment load from the eroded lavakas can damage the infrastructure (collapses roads, bridges and buildings) and may destroy agricultural land (swamp fields). The distribution of lavakas is very diverse: despite the same climatologic, geological environment and anthropogenic effects a large difference in density of lavakas can be observed. For this reason it cannot be fully constrained how lavakas form and develop. Their formation is affected by natural factors (hydrological and climatic effects, geology, tectonics, vegetation, etc.) and also by anthropogenic influences (deforestation, grassland burning, overgrazing). The basic condition for the formation of lavakas often includes the petrographic characteristics of the area. Lavaka-generating substrates can be separated into two main weathered units: thin upper laterite (less than one meter) and thicker deeper saprolite (several tens of meters) on the crystalline basement. This study focuses on a mid-slope lavaka, in the area of Tsiafahy, in Madagascar's Central Highlands. To ascertain the composition of the material and to evaluate the hydraulic conductivity of the lateritic and saprolitic profile on precambrian magmatic basement, we investigated the grain size distribution and mineral composition of an active lavaka. Our results show the significance of water on

  5. Violences conjugales à Antananarivo (Madagascar): un enjeu de santé publique

    PubMed Central

    Gastineau, Bénédicte; Gathier, Lucy

    2012-01-01

    Introduction La violence conjugale a été étudiée dans beaucoup de pays développés mais peu en Afrique subsaharienne. Madagascar est un pays où ce phénomène est peu documenté. Méthodes En 2007, une enquête sur la violence conjugale à Antananarivo (ELVICA) a été menée sur la violence conjugale envers les femmes dans la capitale malgache. ELVICA a interrogé 400 femmes en union, de 15 à 59 ans. Des informations sur les caractéristiques démographiques, socioéconomiques des couples ont été collectées ainsi que sur les actes de violences physiques des hommes sur leurs épouses. L’objectif de cet article est d’identifier les facteurs de risques de la violence conjugale grave, celle qui a des conséquences sur la santé physique des femmes. Résultats Trente-cinq pour cent des femmes qui ont déclaré avoir subi au moins une forme de violence physique au cours des 12 mois précédent l’enquête. Presque la moitié (46%) des femmes violentées ont déclaré avoir déjà eu des hématomes, et environ un quart (23%) des plaies avec saignement. Vingt-deux pour cent ont déjà dû consulter un médecin. Parmi les nombreuses variables socioéconomiques et démographiques testées, quelques-unes sont associées positivement au risque de violence conjugale grave: le fait pour une femme d’être en union consensuelle et d’avoir une activité professionnelle. Il y aussi un lien entre la violence subie et l’autonomie des femmes (liberté accordée par le mari de travailler, de circuler, de voir sa famille). Conclusion A Madagascar, comme ailleurs, la lutte contre les violences conjugales est un élément majeur de l’amélioration du statut et de la santé des femmes. PMID:22514757

  6. Diurnal resting in brown lemurs in a dry deciduous forest, northwestern Madagascar: implications for seasonal thermoregulation.

    PubMed

    Sato, Hiroki

    2012-07-01

    Decreased activity has been reported in both nocturnal and diurnal primates during the prolonged dry season in western Madagascar, and this has been interpreted as a reaction to the severe environment, with its food scarcity and/or thermal stress. Several day-active lemurs rest more as trees defoliate, although the reason for this is unclear. To understand the mechanism underpinning the diurnal resting of lemurs in seasonal deciduous forests, I observed common brown lemurs (Eulemur fulvus fulvus) for one year in Ankarafantsika National Park, northwestern Madagascar. In Ankarafantsika, despite high fruit availability during the dry season, brown lemurs are known to engage in diurnal resting. To examine the effects of thermal factors and defoliation on lemur inactivity, I recorded the activity of a troop at 1 min intervals, hourly ambient temperature, daily rainfall, and weather during observations (06:00-18:00). I quantified the amount of leaves biweekly for 680 trees. I tested correlations between percentages of resting time and each factor across hours during the day and across seasons. During the rainy season, resting time did not differ between sunny and cloudy days, and lemurs were active throughout the daytime. At the hourly level during the dry season, lemurs rested exclusively at midday, apparently at peak sunlight intensity rather than at peak ambient temperature. At seasonal level, percentages of total resting time from 08:00 to 16:00 were greater during dry season (81.9%) than during rainy season (62.6%), and percentages increased as ambient temperatures increased. Defoliation was related to seasonal decrease in weekly rainfall, which served as an index of water retained in the forest. Defoliation probably reflected aridification as well as the penetration of sunlight into the forest. Diurnal resting increased as both the amount of leaves and weekly rainfall decreased seasonally. These results suggest that heat stress under dry conditions may promote

  7. Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009

    PubMed Central

    Razanajatovo, Norosoa Harline; Richard, Vincent; Hoffmann, Jonathan; Reynes, Jean-Marc; Razafitrimo, Girard Marcellin; Randremanana, Rindra Vatosoa; Heraud, Jean-Michel

    2011-01-01

    Background In Madagascar, despite an influenza surveillance established since 1978, little is known about the etiology and prevalence of viruses other than influenza causing influenza-like illnesses (ILIs). Methodology/Principal Findings From July 2008 to June 2009, we collected respiratory specimens from patients who presented ILIs symptoms in public and private clinics in Antananarivo (the capital city of Madagascar). ILIs were defined as body temperature ≥38°C and cough and at least two of the following symptoms: sore throat, rhinorrhea, headache and muscular pain, for a maximum duration of 3 days. We screened these specimens using five multiplex real time Reverse Transcription and/or Polymerase Chain Reaction assays for detection of 14 respiratory viruses. We detected respiratory viruses in 235/313 (75.1%) samples. Overall influenza virus A (27.3%) was the most common virus followed by rhinovirus (24.8%), RSV (21.2%), adenovirus (6.1%), coronavirus OC43 (6.1%), influenza virus B (3.9%), parainfluenza virus-3 (2.9%), and parainfluenza virus-1 (2.3%). Co-infections occurred in 29.4% (69/235) of infected patients and rhinovirus was the most detected virus (27.5%). Children under 5 years were more likely to have one or more detectable virus associated with their ILI. In this age group, compared to those ≥5 years, the risk of detecting more than one virus was higher (OR = 1.9), as was the risk of detecting of RSV (OR = 10.1) and adenovirus (OR = 4.7). While rhinovirus and adenovirus infections occurred year round, RSV, influenza virus A and coronavirus OC43 had defined period of circulation. Conclusions In our study, we found that respiratory viruses play an important role in ILIs in the Malagasy community, particularly in children under 5 years old. These data provide a better understanding of the viral etiology of outpatients with ILI and describe for the first time importance of these viruses in different age group and their period of circulation

  8. Viral etiology of influenza-like illnesses in Antananarivo, Madagascar, July 2008 to June 2009.

    PubMed

    Razanajatovo, Norosoa Harline; Richard, Vincent; Hoffmann, Jonathan; Reynes, Jean-Marc; Razafitrimo, Girard Marcellin; Randremanana, Rindra Vatosoa; Heraud, Jean-Michel

    2011-03-03

    In Madagascar, despite an influenza surveillance established since 1978, little is known about the etiology and prevalence of viruses other than influenza causing influenza-like illnesses (ILIs). From July 2008 to June 2009, we collected respiratory specimens from patients who presented ILIs symptoms in public and private clinics in Antananarivo (the capital city of Madagascar). ILIs were defined as body temperature ≥38°C and cough and at least two of the following symptoms: sore throat, rhinorrhea, headache and muscular pain, for a maximum duration of 3 days. We screened these specimens using five multiplex real time Reverse Transcription and/or Polymerase Chain Reaction assays for detection of 14 respiratory viruses. We detected respiratory viruses in 235/313 (75.1%) samples. Overall influenza virus A (27.3%) was the most common virus followed by rhinovirus (24.8%), RSV (21.2%), adenovirus (6.1%), coronavirus OC43 (6.1%), influenza virus B (3.9%), parainfluenza virus-3 (2.9%), and parainfluenza virus-1 (2.3%). Co-infections occurred in 29.4% (69/235) of infected patients and rhinovirus was the most detected virus (27.5%). Children under 5 years were more likely to have one or more detectable virus associated with their ILI. In this age group, compared to those ≥5 years, the risk of detecting more than one virus was higher (OR = 1.9), as was the risk of detecting of RSV (OR = 10.1) and adenovirus (OR = 4.7). While rhinovirus and adenovirus infections occurred year round, RSV, influenza virus A and coronavirus OC43 had defined period of circulation. In our study, we found that respiratory viruses play an important role in ILIs in the Malagasy community, particularly in children under 5 years old. These data provide a better understanding of the viral etiology of outpatients with ILI and describe for the first time importance of these viruses in different age group and their period of circulation.

  9. Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region.

    PubMed

    Quéméré, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Lounès

    2012-08-07

    The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species' habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed.

  10. [Anopheles mascarensis (De Meillon, 1947): main vector of malaria in the region of Fort-Dauphin (south-east of Madagascar)].

    PubMed

    Marrama, L; Laventure, S; Rabarison, P; Roux, J

    1999-05-01

    Anopheles funestus and Anopheles gambiae s.l. have been considered until now the major vectors of malaria everywhere in Madagascar. Anopheles mascarensis, a mosquito native to Madagascar, has been identified in Sainte-Marie island as a secondary vector only. In 1997, an entomological study was carried out to identify the malaria vectors in the area of Fort-Dauphin, South-East of Madagascar. Every month, mosquitoes were collected from landing catches on human volunteers (from 7:00 am to 5:00 pm inside dwellings and from 7:00 am to 0:00 pm outside) and from knockdown spray-collections indoors. An mascarensis was the most abundant mosquito, the average number of An. mascarensis bites per man/night was 7.6. The sporozoite index was 0.89%. Despite the presence of An. funestus and An. gambiae s.l., An. mascarensis was found to be responsible for 2/3 of the infectious bites (25 infectious bites per man/year). An. mascarensis is widely distributed ih Madagascar but only specimens from the east coast have been found to carry sporozoites of human malaria. Further arguments are thus advanced for the hypothesis according to which a sibling species of An. mascarensis is present in Madagascar.

  11. Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region

    PubMed Central

    Quéméré, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Lounès

    2012-01-01

    The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species’ habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed. PMID:22826244

  12. [Sociocultural aspects of epilepsy in Madagascar. K.A.P. survey carried out in Antananarivo].