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Environmental contaminants of honeybee products in Uganda detected using LC-MS/MS and GC-ECD

Pollinator services and the development of beekeeping as a poverty alleviating tool have gained considerable focus in recent years in sub-Saharan Africa. An improved understanding of the pervasive environmental extent of agro-chemical contaminants is critical to the success of beekeeping development and the production of clean hive products. This study developed and validated a...

Unbiased RNA Shotgun Metagenomics in Social and Solitary Wild Bees Detects Associations with Eukaryote Parasites and New Viruses

.1016/j.jip. 2015 . 01 .006 PMID: 25637516 17. de Miranda JR , Bailey L , Ball BV , Philippe Blanchard GEB , Nor Chejanovsky , Yan-Ping Chen , Laurent Gauthier, Elke Genersch, Dirk C de Graaf , Magali

The buzz about bees and poverty alleviation: Identifying drivers and barriers of beekeeping in sub-Saharan Africa

The potential of beekeeping to mitigate the exposure of rural sub-Sahara African farmers to economic stochasticity has been widely promoted by an array of development agencies. Robust outcome indicators of the success of beekeeping to improve household well-being are unfortunately lacking. This study aimed to identify the key drivers and barriers of beekeeping adoption at the...

First detection of Paenibacillus larvae the causative agent of American Foulbrood in a Ugandan honeybee colony

Descamps 1 Dirk C. de Graaf 1 0 Department of Zoology, Entomology and Fisheries Sciences, College of Natural Sciences, Makerere University , P.O. Box 7062, Kampala , Uganda 1 Laboratory of Molecular

Stress indicator gene expression profiles, colony dynamics and tissue development of honey bees exposed to sub-lethal doses of imidacloprid in laboratory and field experiments

In this study, different context-dependent effects of imidacloprid exposure on the honey bee response were studied. Honey bees were exposed to different concentrations of imidacloprid during a time period of 40 days. Next to these variables, a laboratory-field comparison was conducted. The influence of the chronic exposure on gene expression levels was determined using an in...

Pesticides for Apicultural and/or Agricultural Application Found in Belgian Honey Bee Wax Combs

In a Belgian pilot study honey bee wax combs from ten hives were analyzed on the presence of almost 300 organochlorine and organophosphorous compounds by LC–MS/MS and GC–MS/MS. Traces of 18 pesticides were found and not a single sample was free of residues. The number of residues found per sample ranged from 3 to 13, and the pesticides found could be categorized as (1) pesticides...

Vertical transmission of honey bee viruses in a Belgian queen breeding program

Background The Member States of European Union are encouraged to improve the general conditions for the production and marketing of apicultural products. In Belgium, programmes on the restocking of honey bee hives have run for many years. Overall, the success ratio of this queen breeding programme has been only around 50%. To tackle this low efficacy, we organized sanitary...

Discovery of Lake Sinai virus and an unusual strain of acute bee paralysis virus in West African apiaries

Samples of bees and honey from 101 apiaries were collected in the West African Republic of Benin. Visual inspection revealed high Varroa destructor and Aethina tumida infestations and low Oplostomus fuligineus infestations. A pathogen screen based on bacterial/fungal cultures or microscopic examinations revealed the absence of American and European foulbrood, chalkbrood disease...

How the Venom from the Ectoparasitoid Wasp Nasonia vitripennis Exhibits Anti-Inflammatory Properties on Mammalian Cell Lines

With more than 150,000 species, parasitoids are a large group of hymenopteran insects that inject venom into and then lay their eggs in or on other insects, eventually killing the hosts. Their venoms have evolved into different mechanisms for manipulating host immunity, physiology and behavior in such a way that enhance development of the parasitoid young. The venom from the...

Effect of Bodily Fluids from Honey Bee (Apis mellifera) Larvae on Growth and Genome-Wide Transcriptional Response of the Causal Agent of American Foulbrood Disease (Paenibacillus larvae)

Paenibacillus larvae, the causal agent of American Foulbrood disease (AFB), affects honey bee health worldwide. The present study investigates the effect of bodily fluids from honey bee larvae on growth velocity and transcription for this Gram-positive, endospore-forming bacterium. It was observed that larval fluids accelerate the growth and lead to higher bacterial densities...

Comprehensive Bee Pathogen Screening in Belgium Reveals Crithidia mellificae as a New Contributory Factor to Winter Mortality

Since the last decade, unusually high honey bee colony losses have been reported mainly in North-America and Europe. Here, we report on a comprehensive bee pathogen screening in Belgium covering 363 bee colonies that were screened for 18 known disease-causing pathogens and correlate their incidence in summer with subsequent winter mortality. Our analyses demonstrate that, in...

Holistic screening of collapsing honey bee colonies in Spain: a case study

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...

BeeDoctor, a Versatile MLPA-Based Diagnostic Tool for Screening Bee Viruses

The long-term decline of managed honeybee hives in the world has drawn significant attention to the scientific community and bee-keeping industry. A high pathogen load is believed to play a crucial role in this phenomenon, with the bee viruses being key players. Most of the currently characterized honeybee viruses (around twenty) are positive stranded RNA viruses. Techniques...

Differential Proteomics in Dequeened Honeybee Colonies Reveals Lower Viral Load in Hemolymph of Fertile Worker Bees

The eusocial societies of honeybees, where the queen is the only fertile female among tens of thousands sterile worker bees, have intrigued scientists for centuries. The proximate factors, which cause the inhibition of worker bee ovaries, remain largely unknown; as are the factors which cause the activation of worker ovaries upon the loss of queen and brood in the colony. In an...

Genetic Variability of the Neogregarine Apicystis bombi, an Etiological Agent of an Emergent Bumblebee Disease

The worldwide spread of diseases is considered a major threat to biodiversity and a possible driver of the decline of pollinator populations, particularly when novel species or strains of parasites emerge. Previous studies have suggested that populations of introduced European honeybee (Apis mellifera) and bumblebee species (Bombus terrestris and Bombus ruderatus) in Argentina...

Updated genome assembly and annotation of Paenibacillus larvae, the agent of American foulbrood disease of honey bees

Background As scientists continue to pursue various 'omics-based research, there is a need for high quality data for the most fundamental 'omics of all: genomics. The bacterium Paenibacillus larvae is the causative agent of the honey bee disease American foulbrood. If untreated, it can lead to the demise of an entire hive; the highly social nature of bees also leads to easy...

Finding the missing honey bee genes: lessons learned from a genome upgrade

Childers 3 5 Dirk C de Graaf 4 Griet Debyser 9 Jixin Deng 0 Bart Devreese 9 Eran Elhaik 8 Jay D Evans Leonard J Foster Dan Graur Roderic Guigo 6 HGSC production teams 0 Katharina Jasmin Hoff Michael E Holder

The genomes of two key bumblebee species with primitive eusocial organization

Background The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality...