Amiri E.,University of Aarhus |
Meixner M.,Bieneninstitut Kirchhain |
Nielsen S.L.,University of Aarhus |
Kryger P.,University of Aarhus
PLoS ONE | Year: 2015
Honey bee virus prevalence data are an essential prerequisite for managing epidemic events in a population. A survey study was carried out for seven viruses in colonies representing a healthy Danish honey bee population. In addition, colonies from apiaries with high level Varroa infestation or high level of winter mortality were also surveyed. Results from RT-qPCR showed a considerable difference of virus levels between healthy and sick colonies. In the group of healthy colonies, no virus was detected in 36% of cases, while at least one virus was found in each of the sick colonies. Virus titers varied among the samples, and multiple virus infections were common in both groups with a high prevalence of Sacbrood virus (SBV), Black queen cell virus (BQCV) and Deformed wing virus (DWV). Based on the distribution of virus titers, we established four categories of infection: samples free of virus (C = 0), samples with low virus titer (estimated number of virus copies 0 < C < 103), samples with medium virus titer (103 C < 107) and samples with high virus titer (C107). This allowed us to statistically compare virus levels in healthy and sick colonies. Using categories to communicate virus diagnosis results to beekeepers may help them to reach an informed decision on management strategies to prevent further spread of viruses among colonies. © 2015 Amiri et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Meeus I.,Ghent University |
Smagghe G.,Ghent University |
Siede R.,Bieneninstitut Kirchhain |
Jans K.,Biobest NV |
de Graaf D.C.,Ghent University
Journal of Invertebrate Pathology | Year: 2010
Bumblebees are commercially reared and transported worldwide mainly for pollination of greenhouse tomatoes. Three honeybee viruses have been reported in bumblebees: Acute bee paralysis virus, Kashmir bee virus and Deformed wing virus. We developed a multiplex RT-PCR with primers designed on highly conserved regions of the RNA-dependent RNA polymerase in order to detect a maximum range of viral variants. Rearing facilities and governmental organizations can now thoroughly screen bumblebee colonies with a cost-effective technique with an integrated internal amplification control (IAC) implementable in laboratories that strive for International Organization for Standardization (ISO) certification. © 2010 Elsevier Inc.
Siede R.,Bieneninstitut Kirchhain |
Meixner M.D.,Bieneninstitut Kirchhain |
Buchler R.,Bieneninstitut Kirchhain
Journal of Apicultural Research | Year: 2012
Honey bee colony losses of the last decade have been alarming. Besides the most critical factors, such as parasites and pathogens, losses have been claimed to be linked to immunodeficiency. For the evaluation of this suggestion powerful immunological tests are required. The aim of this study was to obtain further data to characterize common markers of immunity with respect to their experimental practicability. Honey bees were challenged by mechanical and pathogen-like stressors. These were wounding and the injection of buffers and acute bee paralysis virus (ABPV), lipopolysaccharides, lipoteichoic acid, Paenibacillus larvae suspensions and petidoglycan. All experiments were conducted with bees in hoarding cages at a laboratory scale. Immune reactions were quantified by inhibition zone assays and by expression analysis of the genes coding for abaecin, apidaecin, defensin1, hymenoptaecin, hopscotch, Toll and prophenoloxidase. Wounding and injections led to significant immune responses, but the addition of pathogen derived material to the injection solutions did not result in a prominent or specific increase of the defense reactions. A significant upregulation was found for abaecin, defensin1, apidaecin and hymenoptaecin, which was the most responsive gene, showing a 270-fold upregulation after P larvae injection. The upregulation of each of these effector genes was strongly correlated with each other and with Toll, but not with hopscotch or prophenoloxidase.