The Experts below are selected from a list of 2211 Experts worldwide ranked by ideXlab platform
Mariano Higes - One of the best experts on this subject based on the ideXlab platform.
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Nosema apis and Nosema ceranae tissue tropism in worker honey bees apis mellifera
Veterinary Pathology, 2020Co-Authors: Mariano Higes, Pilar Garciapalencia, Almudena Urbieta, Antonio Nanetti, Raquel MartinhernandezAbstract:The microsporidia Nosema apis and Nosema ceranae are major honey bee pathogens that possess different characteristics in terms of the signs they produce, as well as disease development and transmission. Although the ventricular epithelium is generally considered the target tissue, indirect observations led to speculation that N. ceranae may also target other structures, possibly explaining at least some of the differences between these 2 species. To investigate the tropism of Nosema for honey bee tissues, we performed controlled laboratory infections by orally administering doses of 50 000 or 100 000 fresh mature spores of either species. The fat body was isolated from the infected bees, as well as organs from the digestive (esophagus, ventriculus, ileum, rectum), excretory (Malpighian tubules), circulatory (aorta, heart), respiratory (thoracic tracheas), exocrine (hypopharyngeal, mandibular and labial, cephalic, thoracic salivary glands), and sensory/nervous (brain, eyes and associated nerve structures, thoracic nerve ganglia) systems. Tissues were examined by light and electron microscopy at 7, 10, and 15 days postinfection. Both Nosema species were found to infect epithelial cells and clusters of regenerative cells in the ventriculus, and while the ileum and rectum contained spores of the microsporidia in the lumen, these structures did not show overt lesions. No stages of the parasites or cellular lesions were detected in the other organs tested, confirming the high tropism of both species for the ventricular epithelium cells. Thus, these direct histopathological observations indicate that neither of these 2 Nosema species exhibit tropism for honey bee organs other than the ventriculus.
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apoptosis in the pathogenesis of Nosema ceranae microsporidia Nosematidae in honey bees apis mellifera
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Pilar Garciapalencia, Aranzazu Meana, Cristina Botías, Angeles Juarranz, Joyce Diasalmeida, Silvia Rocio Lucena, Raquel MartinhernandezAbstract:Nosema ceranae is a parasite of the epithelial ventricular cells of the honey bee that belongs to the microsporidian phylum, a biological group of single-cell, spore-forming obligate intracellular parasites found in all major animal lineages. The ability of host cells to accommodate a large parasitic burden for several days suggests that these parasites subvert the normal host cells to ensure optimal environmental conditions for growth and development. Once infected, cells can counteract the invasive pathogen by initiating their own death by apoptosis as a defence strategy. To determine whether N. ceranae blocks apoptosis in infected ventricular cells, cell death was assessed in sections of the ventriculum from experimentally infected honey bees using the TUNEL assay and by immunohistochemistry for caspase-3. Ventricular epithelial cells from infected bees were larger than those in the uninfected control bees, and they contained N. ceranae at both mature and immature stages in the cytoplasm. Apoptotic nuclei were only observed in some restricted areas of the ventriculum, whereas apoptosis was typically observed throughout the epithelium in uninfected bees. Indeed, the apoptotic index was higher in uninfected versus infected ventriculi. Our results suggested that N. ceranae prevents apoptosis in epithelial cells of infected ventriculi, a mechanism possible designed to enhance parasite development.
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Nosema ceranae microsporidia a controversial 21st century honey bee pathogen
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Aranzazu Meana, Cristina Botías, Carolina Bartolome, Raquel MartinhernandezAbstract:Summary The worldwide beekeeping sector has been facing a grave threat, with losses up to 100–1000 times greater than those previously reported. Despite the scale of this honey bee mortality, the causes underlying this phenomenon remain unclear, yet they are thought to be multifactorial processes. Nosema ceranae, a microsporidium recently detected in the European bee all over the world, has been implicated in the global phenomenon of colony loss, although its role remains controversial. A review of the current knowledge about this pathogen is presented focussing on discussion related with divergent results, trying to analyse the differences specially based on different methodologies applied and divisive aspects on pathology while considering a biological or veterinarian point of view. For authors, the disease produced by N. ceranae infection cannot be considered a regional problem but rather a global one, as indicated by the wide prevalence of this parasite in multiple hosts. Not only does this type of nosemosis causes a clear pathology on honeybees at both the individual and colony levels, but it also has significant effects on the production of honeybee products.
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microsporidia infecting apis mellifera coexistence or competition is Nosema ceranae replacing Nosema apis
Environmental Microbiology, 2012Co-Authors: Raquel Martinhernandez, Aranzazu Meana, Cristina Botías, Encarna Garrido Bailón, Lourdes Prieto, Amparo Martinezsalvador, Mariano HigesAbstract:Summary Nosema ceranae has been suggested to be replacing Nosema apis in some populations of Apis mellifera honeybees. However, this replacement from one to the other is not supported when studying the distribution and prevalence of both microsporidia in professional apiaries in Spanish territories (transverse study), their seasonal pattern in experimental hives with co-infection or their prevalence at individual level (either in worker bees or drones). Nevertheless, N. ceranae has shown to present a higher prevalence at all the studied levels that could indicate any advantage for its development over N. apis or that it is more adapted to Spanish conditions. Also, both microsporidia show a different pattern of preference for its development according to the prevalence in the different Spanish bioclimatic belts studied. Finally, the fact that all analyses were carried out using an Internal PCR Control (IPC) newly developed guarantees the confidence of the data extracted from the PCR analyses. This IPC provides a useful tool for laboratory detection of honeybee pathogens.
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horizontal transmission of Nosema ceranae microsporidia from worker honeybees to queens apis mellifera
Environmental Microbiology Reports, 2009Co-Authors: Mariano Higes, Pilar Garciapalencia, Raquel Martinhernandez, P Marin, Aranzazu MeanaAbstract:Summary Horizontal transmission from worker honeybees to queens is confirmed in a laboratory essay as a possible route of Nosema ceranae infection in field colonies and pathological repercussions on honeybee queens are described. Lesions are only detected in the epithelial ventricular layer of the infected queens and death occurs within 3 weeks when the nurse workers are experimentally and collectively infected with approximately 5000 viable spores per bee. These data suggest that the higher number of infected house bees, the higher risk of transmission to queens. The presented data may explain the role of house honeybees in natural queen infection, although it is probably that a high proportion of infected house bees must be required to infect the queen.
Aranzazu Meana - One of the best experts on this subject based on the ideXlab platform.
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Nosema ceranae in apis mellifera a 12 years postdetection perspective
Environmental Microbiology, 2018Co-Authors: Raquel Martinhernandez, Claudia Dussaubat, Pilar Garciapalencia, Aranzazu Meana, Carolina Bartolome, Nor Chejanovsky, Yves Le Conte, Anne Dalmon, Alice M Pinto, Victoria SorokerAbstract:Nosema ceranae is a hot topic in honey bee health as reflected by numerous papers published every year. This review presents an update of the knowledge generated in the last 12 years in the field of N. ceranae research, addressing the routes of transmission, population structure and genetic diversity. This includes description of how the infection modifies the honey bee's metabolism, the immune response and other vital functions. The effects on individual honey bees will have a direct impact on the colony by leading to losses in the adult's population. The absence of clear clinical signs could keep the infection unnoticed by the beekeeper for long periods. The influence of the environmental conditions, beekeeping practices, bee genetics and the interaction with pesticides and other pathogens will have a direct influence on the prognosis of the disease. This review is approached from the point of view of the Mediterranean countries where the professional beekeeping has a high representation and where this pathogen is reported as an important threat.
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apoptosis in the pathogenesis of Nosema ceranae microsporidia Nosematidae in honey bees apis mellifera
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Pilar Garciapalencia, Aranzazu Meana, Cristina Botías, Angeles Juarranz, Joyce Diasalmeida, Silvia Rocio Lucena, Raquel MartinhernandezAbstract:Nosema ceranae is a parasite of the epithelial ventricular cells of the honey bee that belongs to the microsporidian phylum, a biological group of single-cell, spore-forming obligate intracellular parasites found in all major animal lineages. The ability of host cells to accommodate a large parasitic burden for several days suggests that these parasites subvert the normal host cells to ensure optimal environmental conditions for growth and development. Once infected, cells can counteract the invasive pathogen by initiating their own death by apoptosis as a defence strategy. To determine whether N. ceranae blocks apoptosis in infected ventricular cells, cell death was assessed in sections of the ventriculum from experimentally infected honey bees using the TUNEL assay and by immunohistochemistry for caspase-3. Ventricular epithelial cells from infected bees were larger than those in the uninfected control bees, and they contained N. ceranae at both mature and immature stages in the cytoplasm. Apoptotic nuclei were only observed in some restricted areas of the ventriculum, whereas apoptosis was typically observed throughout the epithelium in uninfected bees. Indeed, the apoptotic index was higher in uninfected versus infected ventriculi. Our results suggested that N. ceranae prevents apoptosis in epithelial cells of infected ventriculi, a mechanism possible designed to enhance parasite development.
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Nosema ceranae microsporidia a controversial 21st century honey bee pathogen
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Aranzazu Meana, Cristina Botías, Carolina Bartolome, Raquel MartinhernandezAbstract:Summary The worldwide beekeeping sector has been facing a grave threat, with losses up to 100–1000 times greater than those previously reported. Despite the scale of this honey bee mortality, the causes underlying this phenomenon remain unclear, yet they are thought to be multifactorial processes. Nosema ceranae, a microsporidium recently detected in the European bee all over the world, has been implicated in the global phenomenon of colony loss, although its role remains controversial. A review of the current knowledge about this pathogen is presented focussing on discussion related with divergent results, trying to analyse the differences specially based on different methodologies applied and divisive aspects on pathology while considering a biological or veterinarian point of view. For authors, the disease produced by N. ceranae infection cannot be considered a regional problem but rather a global one, as indicated by the wide prevalence of this parasite in multiple hosts. Not only does this type of nosemosis causes a clear pathology on honeybees at both the individual and colony levels, but it also has significant effects on the production of honeybee products.
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microsporidia infecting apis mellifera coexistence or competition is Nosema ceranae replacing Nosema apis
Environmental Microbiology, 2012Co-Authors: Raquel Martinhernandez, Aranzazu Meana, Cristina Botías, Encarna Garrido Bailón, Lourdes Prieto, Amparo Martinezsalvador, Mariano HigesAbstract:Summary Nosema ceranae has been suggested to be replacing Nosema apis in some populations of Apis mellifera honeybees. However, this replacement from one to the other is not supported when studying the distribution and prevalence of both microsporidia in professional apiaries in Spanish territories (transverse study), their seasonal pattern in experimental hives with co-infection or their prevalence at individual level (either in worker bees or drones). Nevertheless, N. ceranae has shown to present a higher prevalence at all the studied levels that could indicate any advantage for its development over N. apis or that it is more adapted to Spanish conditions. Also, both microsporidia show a different pattern of preference for its development according to the prevalence in the different Spanish bioclimatic belts studied. Finally, the fact that all analyses were carried out using an Internal PCR Control (IPC) newly developed guarantees the confidence of the data extracted from the PCR analyses. This IPC provides a useful tool for laboratory detection of honeybee pathogens.
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Natural infection by Nosema ceranae causes similar lesions as in experimentally infected caged-worker honey bees (Apis mellifera)
Journal of Apicultural Research, 2010Co-Authors: Pilar García-palencia, Raquel Martín-hernández, Amelia-virginia González-porto, Pilar Marín, Aranzazu MeanaAbstract:SummaryIn this report, the pathological features observed in honey bees naturally infected with the microsporidium Nosema ceranae throughout a year are described. The lesions produced under natural conditions are similar to those observed in experimentally caged worker honey bees. N. ceranae is able to reproduce inside epithelial cells and multiply all through the year causing lesions in host-cells, characterized by a progressive and irreversible destruction of the epithelial layer of the ventriculus, which can lead to major negative repercussions on the normal process of digestion, with critical consequences on honey bee and colony viability. It is remarkable that factors such as continuous access to fresh pollen around the apiary or temperature and humidity variations throughout the year in different seasons did not apparently influence the development of the endogenous cycle of this parasite under field conditions.
Raquel Martinhernandez - One of the best experts on this subject based on the ideXlab platform.
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Nosema apis and Nosema ceranae tissue tropism in worker honey bees apis mellifera
Veterinary Pathology, 2020Co-Authors: Mariano Higes, Pilar Garciapalencia, Almudena Urbieta, Antonio Nanetti, Raquel MartinhernandezAbstract:The microsporidia Nosema apis and Nosema ceranae are major honey bee pathogens that possess different characteristics in terms of the signs they produce, as well as disease development and transmission. Although the ventricular epithelium is generally considered the target tissue, indirect observations led to speculation that N. ceranae may also target other structures, possibly explaining at least some of the differences between these 2 species. To investigate the tropism of Nosema for honey bee tissues, we performed controlled laboratory infections by orally administering doses of 50 000 or 100 000 fresh mature spores of either species. The fat body was isolated from the infected bees, as well as organs from the digestive (esophagus, ventriculus, ileum, rectum), excretory (Malpighian tubules), circulatory (aorta, heart), respiratory (thoracic tracheas), exocrine (hypopharyngeal, mandibular and labial, cephalic, thoracic salivary glands), and sensory/nervous (brain, eyes and associated nerve structures, thoracic nerve ganglia) systems. Tissues were examined by light and electron microscopy at 7, 10, and 15 days postinfection. Both Nosema species were found to infect epithelial cells and clusters of regenerative cells in the ventriculus, and while the ileum and rectum contained spores of the microsporidia in the lumen, these structures did not show overt lesions. No stages of the parasites or cellular lesions were detected in the other organs tested, confirming the high tropism of both species for the ventricular epithelium cells. Thus, these direct histopathological observations indicate that neither of these 2 Nosema species exhibit tropism for honey bee organs other than the ventriculus.
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Nosema ceranae in apis mellifera a 12 years postdetection perspective
Environmental Microbiology, 2018Co-Authors: Raquel Martinhernandez, Claudia Dussaubat, Pilar Garciapalencia, Aranzazu Meana, Carolina Bartolome, Nor Chejanovsky, Yves Le Conte, Anne Dalmon, Alice M Pinto, Victoria SorokerAbstract:Nosema ceranae is a hot topic in honey bee health as reflected by numerous papers published every year. This review presents an update of the knowledge generated in the last 12 years in the field of N. ceranae research, addressing the routes of transmission, population structure and genetic diversity. This includes description of how the infection modifies the honey bee's metabolism, the immune response and other vital functions. The effects on individual honey bees will have a direct impact on the colony by leading to losses in the adult's population. The absence of clear clinical signs could keep the infection unnoticed by the beekeeper for long periods. The influence of the environmental conditions, beekeeping practices, bee genetics and the interaction with pesticides and other pathogens will have a direct influence on the prognosis of the disease. This review is approached from the point of view of the Mediterranean countries where the professional beekeeping has a high representation and where this pathogen is reported as an important threat.
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apoptosis in the pathogenesis of Nosema ceranae microsporidia Nosematidae in honey bees apis mellifera
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Pilar Garciapalencia, Aranzazu Meana, Cristina Botías, Angeles Juarranz, Joyce Diasalmeida, Silvia Rocio Lucena, Raquel MartinhernandezAbstract:Nosema ceranae is a parasite of the epithelial ventricular cells of the honey bee that belongs to the microsporidian phylum, a biological group of single-cell, spore-forming obligate intracellular parasites found in all major animal lineages. The ability of host cells to accommodate a large parasitic burden for several days suggests that these parasites subvert the normal host cells to ensure optimal environmental conditions for growth and development. Once infected, cells can counteract the invasive pathogen by initiating their own death by apoptosis as a defence strategy. To determine whether N. ceranae blocks apoptosis in infected ventricular cells, cell death was assessed in sections of the ventriculum from experimentally infected honey bees using the TUNEL assay and by immunohistochemistry for caspase-3. Ventricular epithelial cells from infected bees were larger than those in the uninfected control bees, and they contained N. ceranae at both mature and immature stages in the cytoplasm. Apoptotic nuclei were only observed in some restricted areas of the ventriculum, whereas apoptosis was typically observed throughout the epithelium in uninfected bees. Indeed, the apoptotic index was higher in uninfected versus infected ventriculi. Our results suggested that N. ceranae prevents apoptosis in epithelial cells of infected ventriculi, a mechanism possible designed to enhance parasite development.
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Nosema ceranae microsporidia a controversial 21st century honey bee pathogen
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Aranzazu Meana, Cristina Botías, Carolina Bartolome, Raquel MartinhernandezAbstract:Summary The worldwide beekeeping sector has been facing a grave threat, with losses up to 100–1000 times greater than those previously reported. Despite the scale of this honey bee mortality, the causes underlying this phenomenon remain unclear, yet they are thought to be multifactorial processes. Nosema ceranae, a microsporidium recently detected in the European bee all over the world, has been implicated in the global phenomenon of colony loss, although its role remains controversial. A review of the current knowledge about this pathogen is presented focussing on discussion related with divergent results, trying to analyse the differences specially based on different methodologies applied and divisive aspects on pathology while considering a biological or veterinarian point of view. For authors, the disease produced by N. ceranae infection cannot be considered a regional problem but rather a global one, as indicated by the wide prevalence of this parasite in multiple hosts. Not only does this type of nosemosis causes a clear pathology on honeybees at both the individual and colony levels, but it also has significant effects on the production of honeybee products.
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microsporidia infecting apis mellifera coexistence or competition is Nosema ceranae replacing Nosema apis
Environmental Microbiology, 2012Co-Authors: Raquel Martinhernandez, Aranzazu Meana, Cristina Botías, Encarna Garrido Bailón, Lourdes Prieto, Amparo Martinezsalvador, Mariano HigesAbstract:Summary Nosema ceranae has been suggested to be replacing Nosema apis in some populations of Apis mellifera honeybees. However, this replacement from one to the other is not supported when studying the distribution and prevalence of both microsporidia in professional apiaries in Spanish territories (transverse study), their seasonal pattern in experimental hives with co-infection or their prevalence at individual level (either in worker bees or drones). Nevertheless, N. ceranae has shown to present a higher prevalence at all the studied levels that could indicate any advantage for its development over N. apis or that it is more adapted to Spanish conditions. Also, both microsporidia show a different pattern of preference for its development according to the prevalence in the different Spanish bioclimatic belts studied. Finally, the fact that all analyses were carried out using an Internal PCR Control (IPC) newly developed guarantees the confidence of the data extracted from the PCR analyses. This IPC provides a useful tool for laboratory detection of honeybee pathogens.
Cristina Botías - One of the best experts on this subject based on the ideXlab platform.
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apoptosis in the pathogenesis of Nosema ceranae microsporidia Nosematidae in honey bees apis mellifera
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Pilar Garciapalencia, Aranzazu Meana, Cristina Botías, Angeles Juarranz, Joyce Diasalmeida, Silvia Rocio Lucena, Raquel MartinhernandezAbstract:Nosema ceranae is a parasite of the epithelial ventricular cells of the honey bee that belongs to the microsporidian phylum, a biological group of single-cell, spore-forming obligate intracellular parasites found in all major animal lineages. The ability of host cells to accommodate a large parasitic burden for several days suggests that these parasites subvert the normal host cells to ensure optimal environmental conditions for growth and development. Once infected, cells can counteract the invasive pathogen by initiating their own death by apoptosis as a defence strategy. To determine whether N. ceranae blocks apoptosis in infected ventricular cells, cell death was assessed in sections of the ventriculum from experimentally infected honey bees using the TUNEL assay and by immunohistochemistry for caspase-3. Ventricular epithelial cells from infected bees were larger than those in the uninfected control bees, and they contained N. ceranae at both mature and immature stages in the cytoplasm. Apoptotic nuclei were only observed in some restricted areas of the ventriculum, whereas apoptosis was typically observed throughout the epithelium in uninfected bees. Indeed, the apoptotic index was higher in uninfected versus infected ventriculi. Our results suggested that N. ceranae prevents apoptosis in epithelial cells of infected ventriculi, a mechanism possible designed to enhance parasite development.
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Nosema ceranae microsporidia a controversial 21st century honey bee pathogen
Environmental Microbiology Reports, 2013Co-Authors: Mariano Higes, Aranzazu Meana, Cristina Botías, Carolina Bartolome, Raquel MartinhernandezAbstract:Summary The worldwide beekeeping sector has been facing a grave threat, with losses up to 100–1000 times greater than those previously reported. Despite the scale of this honey bee mortality, the causes underlying this phenomenon remain unclear, yet they are thought to be multifactorial processes. Nosema ceranae, a microsporidium recently detected in the European bee all over the world, has been implicated in the global phenomenon of colony loss, although its role remains controversial. A review of the current knowledge about this pathogen is presented focussing on discussion related with divergent results, trying to analyse the differences specially based on different methodologies applied and divisive aspects on pathology while considering a biological or veterinarian point of view. For authors, the disease produced by N. ceranae infection cannot be considered a regional problem but rather a global one, as indicated by the wide prevalence of this parasite in multiple hosts. Not only does this type of nosemosis causes a clear pathology on honeybees at both the individual and colony levels, but it also has significant effects on the production of honeybee products.
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microsporidia infecting apis mellifera coexistence or competition is Nosema ceranae replacing Nosema apis
Environmental Microbiology, 2012Co-Authors: Raquel Martinhernandez, Aranzazu Meana, Cristina Botías, Encarna Garrido Bailón, Lourdes Prieto, Amparo Martinezsalvador, Mariano HigesAbstract:Summary Nosema ceranae has been suggested to be replacing Nosema apis in some populations of Apis mellifera honeybees. However, this replacement from one to the other is not supported when studying the distribution and prevalence of both microsporidia in professional apiaries in Spanish territories (transverse study), their seasonal pattern in experimental hives with co-infection or their prevalence at individual level (either in worker bees or drones). Nevertheless, N. ceranae has shown to present a higher prevalence at all the studied levels that could indicate any advantage for its development over N. apis or that it is more adapted to Spanish conditions. Also, both microsporidia show a different pattern of preference for its development according to the prevalence in the different Spanish bioclimatic belts studied. Finally, the fact that all analyses were carried out using an Internal PCR Control (IPC) newly developed guarantees the confidence of the data extracted from the PCR analyses. This IPC provides a useful tool for laboratory detection of honeybee pathogens.
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south american native bumblebees hymenoptera apidae infected by Nosema ceranae microsporidia an emerging pathogen of honeybees apis mellifera
Environmental Microbiology Reports, 2009Co-Authors: Santiago Plischuk, Raquel Martinhernandez, Aranzazu Meana, Cristina Botías, Lourdes Prieto, Mariano Lucia, Alberto Horacio Abrahamovich, Carlos E Lange, Mariano HigesAbstract:As pollination is a critical process in both human-managed and natural terrestrial ecosystems, pollinators provide essential services to both nature and humans. Pollination is mainly due to the action of different insects, such as the bumblebee and the honeybee. These important ecological and economic roles have led to widespread concern over the recent decline in pollinator populations that has been detected in many regions of the world. While this decline has been attributed in some cases to changes in the use of agricultural land, the effects of parasites could play a significant role in the reduction of these populations. For the first time, we describe here the presence of Nosema ceranae, an emerging honeybee pathogen, in three species of Argentine native bumblebees. A total of 455 bumblebees belonging to six species of genus Bombus were examined. PCR results showed that three of the species are positive to N. ceranae (Bombus atratus, Bombus morio and Bombus bellicosus). We discuss the appearance of this pathogen in the context of the population decline of this pollinators.
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the presence of Nosema ceranae microsporidia in north african honey bees apis mellifera intermissa
Journal of Apicultural Research, 2009Co-Authors: Mariano Higes, Raquel Martinhernandez, Cristina Botías, Encarna Garridobailon, Aranzazu MeanaAbstract:(2009). The presence of Nosema ceranae (Microsporidia) in North African honey bees (Apis mellifera intermissa) Journal of Apicultural Research: Vol. 48, No. 3, pp. 217-219.
Robert J Paxton - One of the best experts on this subject based on the ideXlab platform.
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brain transcriptomes of honey bees apis mellifera experimentally infected by two pathogens black queen cell virus and Nosema ceranae
Genomics data, 2016Co-Authors: Robert J Paxton, Cédric Alaux, Cynthia Mcdonnell, Vincent Doublet, Emeric Dubois, Sabine Nidelet, Robin F A Moritz, Yves Le ConteAbstract:Regulation of gene expression in the brain plays an important role in behavioral plasticity and decision making in response to external stimuli. However, both can be severely affected by environmental factors, such as parasites and pathogens. In honey bees, the emergence and re-emergence of pathogens and potential for pathogen co-infection and interaction have been suggested as major components that significantly impaired social behavior and survival. To understand how the honey bee is affected and responds to interacting pathogens, we co-infected workers with two prevalent pathogens of different nature, the positive single strand RNA virus Black queen cell virus (BQCV), and the Microsporidia Nosema ceranae, and explored gene expression changes in brains upon single infections and co-infections. Our data provide an important resource for research on honey bee diseases, and more generally on insect host-pathogen and pathogen-pathogen interactions. Raw and processed data are publicly available in the NCBI/GEO database: (http://www.ncbi.nlm.nih.gov/geo/) under accession number GSE81664.
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European isolates of the Microsporidia Nosema apis and Nosema ceranae have similar virulence in laboratory tests on European worker honey bees
Apidologie, 2016Co-Authors: Myrsini E. Natsopoulou, Vincent Doublet, Robert J PaxtonAbstract:AbstractNosema apis and Nosema ceranae are gut parasites that infect western honey bees (Apis mellifera) worldwide. N. ceranae is an exotic infectious disease agent of A. mellifera, having been originally described in the Asian honey bee (Apis cerana), while N. apis is native to the western honey bee. To better understand the dynamics and epidemiology of the two pathogens, we examined the impact of European isolates of both Microsporidia on the longevity of European A. mellifera in a controlled laboratory experiment. N. ceranae caused slightly higher host mortality compared to N. apis, but differences in virulence were subtle and non-significant. Variation across published studies may reflect geographic differences in the coadaptation of hosts and parasites and seasonal differences in host susceptibility.
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within host competition among the honey bees pathogens Nosema ceranae and deformed wing virus is asymmetric and to the disadvantage of the virus
Journal of Invertebrate Pathology, 2015Co-Authors: Vincent Doublet, Robert J Paxton, Myrsini E. Natsopoulou, Luise ZschiescheAbstract:Two pathogens co-infecting a common host can either interact positively (facilitation), negatively (competition) or act independently. A correlative study has suggested that two pathogens of the honey bee, Nosema ceranae and Deformed wing virus (DWV), interact negatively within a host (Costa et al., 2011). To test this hypothesis, we sequentially co-infected honey bees with these pathogens in a reciprocally crossed experimental design. Prior establishment in the host ventriculus by N. ceranae inhibited DWV while prior infection by DWV did not impact N. ceranae, highlighting an asymmetry in the competitive interaction between these emerging pathogens.
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does infection by Nosema ceranae cause colony collapse disorder in honey bees apis mellifera
Journal of Apicultural Research, 2010Co-Authors: Robert J PaxtonAbstract:Summary Nosema ceranae is an emergent and potentially virulent pathogen of the honey bee (Apis mellifera) that has spread across the world in the last 10 or so years. Its precise origin and timing of spread are currently unclear because of a lack of appropriate genetic markers and inadequate sampling in putative Asian source populations. Though it has been dismissed as a cause of CCD in the USA based on correlational analyses of snapshot sampling of diseased hives, observations of naturally infected colonies suggest that it leads to colony collapse in Spain. Experiments are sorely needed to investigate its impact on individuals and colonies, and to pin down a causal relationship between N. ceranae and colony collapse. Whether N. ceranae is displacing N. apis is uncertain. For temperate zone apiculturalists, global climate change may mean that N. ceranae presents more of a challenge than has hitherto been considered the case.
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Nosema ceranae has infected apis mellifera in europe since at least 1998 and may be more virulent than Nosema apis
Apidologie, 2007Co-Authors: Robert J Paxton, Julia Klee, Seppo Korpela, Ingemar FriesAbstract:Nosema ceranae, a microsporidian formerly regarded as confined to its Asiatic host Apis cerana, has recently been shown to parasitise Apis mellifera and to have spread throughout most of the world in the past few years. Using a temporal sequence of N = 28 Nosema isolates from Finland from 1986–2006, we now find (i) that N. ceranae has been present in Europe since at least 1998 and (ii) that it has increased in frequency across this time period relative to Nosema apis, possibly leading to higher mean spore loads per bee. We then present results of a single laboratory infection experiment in which we directly compare the virulence of N. apis with N. ceranae. Though lacking replication, our results suggest (iii) that both parasites build up to equal numbers per bee by day 14 post infection but that (iv) N. ceranae induces significantly higher mortality relative to N. apis.
