Under vintrarna 2006/2007 och 2007/2008 vittnade man i USA om storskaliga förluster avhonungsbin (Apis mellifera). Gemensamma symptom för dessa förluster var att arbetarbinförsvann från kolonierna fastän det fanns rikligt med mat och inga tecken på infektion av någonparasit. Fenomenet fick namnet Colony Collapse Disorder (CCD) eftersom det slutgiltigastadiet var att kolonierna kollapsade. Denna översiktstudie ämnar till att reda ut begreppetCCD och se över vilka potentiella orsaker den rådande forskningen föreslår och vad man harkommit fram till sedan utbrottet 2006. Resultaten indikerar att det antagligen inte är en ensamfaktor bakom CCD utan att flera faktorer samverkar. Det finns ett antal hot mot bina medsymptom som liknar CCD och som antas bidra till försvinnandet. Ett hot är det parasitiskakvalstret Varroa destructor som förutom att det suger binas hemolymfa även agerar vektor åtflera CCD-förknippade patogener som Nosema ceranae och Israeli acute paralysis virus(IAPV). Dessutom sänker V. destructor binas immunförsvar vilket gör att virus som överförsvia kvalstret replikeras snabbare och blir dödligare. Man har även visat att vanligt förekommandebekämpningsmedel kan göra bina mer mottagliga för sjukdomar. Där hittade man ettsignifikant samband med just N. ceranae vilket är i enlighet med teorin om att flera faktorersamverkar. I nuläget bidrar CCD fortfarande till bidöd men är inte lika akut som 2006/2007.Istället är det andra hot såsom biodlares svårighet att behandla invasion av varroakvalster,kalla vintrar och att bisamhällen svälter ihjäl för att de invintras i för små populationer, som ärett större hot än CCD.

Thesis (M.S. in entomology)--Washington State University, May 2010. / Title from PDF title page (viewed on July 12, 2010). "Department of Entomology." Includes bibliographical references.

No description available.

Nosema ceranae, a microsporidian, has been given much attention in recent years as it has been linked with Colony Collapse Disorder (CCD), which leads to the sudden deaths of honey bee colonies. It has been described that many pathogenic organisms secrete virulence factors in order to hijack its host`s cellular functions, but in most cases the underlying mechanisms of this process still remains to be deciphered. Cornman et al. (2009) have identified in N. ceranae a list of putative effector proteins (called secretome) destined to be secreted into the host, and I have taken this list for further investigation using a bioinformatical and experimental approaches. The principal aim of this project was to generate a N. ceranae ORFeome for genes predicted to be secreted, elucidate the function of effector candidates important for N. ceranae biology and/or pathogenicity, as well as to investigate any interactions between N. ceranae proteins and its host utilising two eukaryotic model organisms, budding yeast, S. cerevisiae, and fruit fly, D. melanogaster. A library of S. cerevisiae strains expressing N. ceranae proteins was generated utilising the Gateway® technology, and phenotypic and localisation screens were undertaken to investigate the N. ceranae secretome. Two N. ceranae ORFs, NcORF-15 (NcORF-02039) and NcORF-16 (NcORF-01159) encoding a putative thioredoxin and a hexokinase, respectively, were subjected to yeast complementation assays in order to assess their catalytic activity. NcORF-15, the putative thioredoxin, was able to rescue the sensitive phenotype of S. cerevisiae Δtrx2 under oxidative stress, whereas NcORF-16, the putative hexokinase, did not complement YSH7.4-3C, a triple knockout lacking hexokinase activity. A third N. ceranae effector candidate NcORF-4 (NcORF-00654), a putative proteasome subunit, was investigated for its nuclear localisation and protein interactions in both S. cerevisiae and D. melanogaster.

Brevibacillus laterosporus (B. laterosporus) is a pathogen difficult to distinguish from Paenibacillus larvae (P. larvae), and contributes to Colony Collapse Disorder (CCD) of honeybees. To develop a biocontrol agent to limit its presence, bacteriophages were isolated from Utah County soil samples and used to infect B. laterosporus isolated from Utah County honey and larvae samples. Since CCD is prevalent in Utah beehives, bacteriophage that infect and lyse B. laterosporus may be isolated and characterized. Pathogens were isolated from soil samples, and 16S rRNA gene tests initially identified the strains as P. larvae. Bacteriophages were isolated, purified, and amplified sufficiently to obtain images by electron microscope and genome sequencing by 454 pyrosequencing. Genomes were annotated with DNA Master, a Multiple Document Interface (MDI) program. Open reading frames (ORF's) were compared to the National Center for Biotechnology Information's (NCBI) database of primary biological sequence information via the Basic Local Alignment Search Tool (BLAST) algorithm. Later testing determined the pathogen to actually be B. laterosporus. Plaques demonstrated lytic activity, and electron microscopy revealed bacteriophages of the myoviridae family. The five sequenced genomes were composed of linear dsDNA ranging from 45,552 to 58,572 base pairs in length, 92 to 100 genes per genome, and a 38.10% to 41.44% range of G + C content. Discovering and describing new bacteriophages is a reasonably reproducible process and contributes to appreciating the diverse relationships between bacteriophage, bacteria, and eukaryota. Scientific facilitation of the bacteriophages role in limiting detrimental bacteria may contribute as an adjunctive therapy for CCD.

Det här arbetet handlar om tambins inverkan på naturligt förekommande pollinatörer. Min frågeställning berör: tillgången på näring, hälsotillståndet och populationsnivån hos naturligt förekommande pollinatörer i förhållande till tambins närvaro. Det som framkommit av den här litteraturstudien är att introducerade tambin leder till att naturligt förekommande pollinatörer minskar i antal kring bikuporna, en del arter söker föda på andra blommor eller senare på dygnet än tidigare. Den minskade tillgången på föda som denna konkurrens innebär har en negativ inverkan på humlors kroppsstorlek och därmed deras överlevnad. Samt att tambin kan föra över patogener så som varroakvalster, nosemasjuka och deformed wing virus till humlor vilket leder till minskad livslängd och sämre fortplantning. / This study is about the impact of honeybees on native pollinators. My questions concerns: availability of food, the health and population level of native pollinators in relation to the presence of honeybees. What has emerged from this literature review is that the introduction of honeybees lead to a decline in numbers of bee and bumblebee pollinators in proximity of the hives and also alters their behaviour, some species choose to forage on other flowers, or later in the day than before honeybees where introduced. The reduced availability of food that this competition induces has a negative impact on the size of bumblebees body’s and thus their survival. What was also discovered was that honeybees can transfer pathogens such as varroa mites, the microsporidium Nosema ceranae and deformed wing virus to bumblebees, leading to reduced life expectancy and poor propagation.

No description available.

In this study, the effects of the neonicotinoid pesticide, thiamethoxam, are examined through the Proboscis Extension Response (PER) in honey bees (Apis mellifera). PER is a form of classical conditioning applied to honey bees through scent and reward association which quantifies learning rates. Results between groups treated with thiamethoxam did not differ significantly from untreated control groups. Potential reasons for these results are discussed. The method and experimental apparatus for testing the PER assay are also discussed.