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Marchamalo, Spain

Sanchez-Hernandez L.,University of Valladolid | Hernandez-Dominguez D.,University of Valladolid | Martin M.T.,University of Valladolid | Nozal M.J.,University of Valladolid | And 2 more authors.
Journal of Chromatography A | Year: 2016

A study was carried out to evaluate the possible presence of thiamethoxam, clothianidin and imidacloprid, as well as the metabolic breakdown products of these three neonicotinoids in pollen and honey obtained from brood chamber combs of honeybee colonies located next to sunflower and maize crops from coated seeds. Samples were analyzed by liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry detector, in combination with accurate mass tools such as diagnostic ions by exact mass, chlorine mass filters, and MS/MS experiments. The presence of thiamethoxam and clothianidin was confirmed in some of the pollen samples analyzed. Moreover, different metabolites of neonicotinoids were tentatively detected in the pollen and honey samples collected. The results suggested that four metabolites were found in the honey samples, while for pollen samples eleven metabolites were identified; among these, five were considered for the first time as metabolic breakdown products in sunflower and maize plants. © 2015 Elsevier B.V.. Source

Higes M.,Centro Apicola Regional CAR | Meana A.,Complutense University of Madrid | Bartolome C.,University of Santiago de Compostela | Botias C.,Centro Apicola Regional CAR | Martin-Hernandez R.,Institute Recursos Humanos para la Ciencia y la Tecnologia INCRECYT
Environmental Microbiology Reports | Year: 2013

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. Journal compilation © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd. Source

Botias C.,Centro Apicola Regional CAR | Martin-Hernandez R.,Centro Apicola Regional CAR | Martin-Hernandez R.,Institute Recursos Humanos para la Ciencia y la Tecnologia INCRECYT | Garrido-Bailon E.,Centro Apicola Regional CAR | And 5 more authors.
Research in Veterinary Science | Year: 2012

Microsporidiosis caused by infection with Nosema apis or Nosema ceranae has become one of the most widespread diseases of honey bees and can cause important economic losses for beekeepers. Honey can be contaminated by spores of both species and it has been reported as a suitable matrix to study the field prevalence of other honey bee sporulated pathogens. Historical honey sample collections from the CAR laboratory (Centro Apícola Regional) were analyzed by PCR to identify the earliest instance of emergence, and to determine whether the presence of Nosema spp. in honey was linked to the spread of these microsporidia in honey bee apiaries. A total of 240 frozen honey samples were analyzed by PCR and the results compared with rates of Nosema spp. infection in worker bee samples from different years and geographical areas. The presence of Nosema spp. in hive-stored honey from naturally infected honey bee colonies (from an experimental apiary) was also monitored, and although collected honey bees resulted in a more suitable sample to study the presence of microsporidian parasites in the colonies, a high probability of finding Nosema spp. in their hive-stored honey was observed. The first honey sample in which N. ceranae was detected dates back to the year 2000. In subsequent years, the number of samples containing N. ceranae tended to increase, as did the detection of Nosema spp. in adult worker bees. The presence of N. ceranae as early as 2000, long before generalized bee depopulation and colony losses in 2004 may be consistent with a long incubation period for nosemosis type C or related with other unknown factors. The current prevalence of nosemosis, primarily due to N. ceranae, has reached epidemic levels in Spain as confirmed by the analysis of worker honey bees and commercial honey. © 2011 Elsevier Ltd. Source

Cepero A.,Centro Apicola Regional CAR | Ravoet J.,Ghent University | Gomez-Moracho T.,Centro Apicola Regional CAR | Gomez-Moracho T.,University of Santiago de Compostela | And 10 more authors.
BMC Research Notes | Year: 2014

Background: Here we present a holistic screening of collapsing colonies from three professional apiaries in Spain. Colonies with typical honey bee depopulation symptoms were selected for multiple possible factors to reveal the causes of collapse. Results: Omnipresent were Nosema ceranae and Lake Sinai Virus. Moderate prevalences were found for Black Queen Cell Virus and trypanosomatids, whereas Deformed Wing Virus, Aphid Lethal Paralysis Virus strain Brookings and neogregarines were rarely detected. Other viruses, Nosema apis, Acarapis woodi and Varroa destructor were not detected. Palinologic study of pollen demonstrated that all colonies were foraging on wild vegetation. Consequently, the pesticide residue analysis was negative for neonicotinoids. The genetic analysis of trypanosomatids GAPDH gene, showed that there is a large genetic distance between Crithidia mellificae ATCC30254, an authenticated cell strain since 1974, and the rest of the presumed C. mellificae sequences obtained in our study or published. This means that the latter group corresponds to a highly differentiated taxon that should be renamed accordingly. Conclusion: The results of this study demonstrate that the drivers of colony collapse may differ between geographic regions with different environmental conditions, or with different beekeeping and agricultural practices. The role of other pathogens in colony collapse has to bee studied in future, especially trypanosomatids and neogregarines. Beside their pathological effect on honey bees, classification and taxonomy of these protozoan parasites should also be clarified. © 2014Cepero et al.; licensee BioMed Central Ltd. Source

Botias C.,Centro Apicola Regional CAR | Martin-Hernandez R.,Centro Apicola Regional CAR | Martin-Hernandez R.,Institute Recursos Humanos para la Ciencia y Tecnologia | Meana A.,Complutense University of Madrid | Higes M.,Centro Apicola Regional CAR
Parasitology Research | Year: 2012

Nosemosis is one of the most widespread of the adult honey bee diseases and causes major economic losses to beekeepers. Two microsporidia have been described infecting honey bees worldwide, Nosema apis and Nosema ceranae, whose seasonality and pathology differ markedly. An increasing prevalence of microsporidian infections in honey bees has been observed worldwide during the last years. Because nosemosis has detrimental effects on both strength and productivity of the infected colonies, an accurate and reliable method to evaluate the presence of Nosema in honey bee colonies is needed. In this study a high degree of variability in the detection of microsporidia depending on the random subsample analyzed was found, suggesting that both sample size and the time of collection (month and day of sampling) notably affect the diagnosis. © Springer-Verlag 2011. Source

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