Evaluation of Fumagilin-B® and other potential alternative chemotherapies against Nosema ceranae-infected honeybees (Apis mellifera) in cage trial assays

International audienceAbstractFumagilin-B® is the only currently registered chemical treatment available to combat nosema disease in apiculture. Fumagillol, the basic hydrolysis product of fumagillin, two semisynthetic fumagillin analogues, and four in-house purely synthetic compounds which were designed to mimic the mode of action of fumagillin against the methionine aminopeptidase type 2 (MetAP-2) enzyme, was observed to exhibit statistically significant biological activity against Nosema ceranae-infected caged bees. None of these compounds were, however, as effective as Fumagilin-B®. The commercially available thymol and enilconazole also exhibited activity against N. ceranae, with thymol being the most promising chemical treatment other than Fumagilin-B®. High cumulative bee mortality was associated with the therapeutic dosage of Fumagilin-B® during our study, suggesting the need for continued investigation

The effect of dicyclohexylamine and fumagillin on Nosema ceranae-infected honey bee (Apis mellifera) mortality in cage trial assays

International audienceAbstractBoth commercially available fumagillin-based treatments for honey bees (Apis mellifera), Fumagilin-B® as well as Fumidil-B®, contain the reportedly genotoxic and tumorigenic compound dicyclohexylamine (DCH) as the counter ion in the fumagillin-DCH salt. The effect of DCH, purified fumagillin (containing no DCH), and the commercial formulation Fumagilin-B® (containing both fumagillin as well as DCH) on the mortality of caged Nosema ceranae-infected honey bees was investigated. A statistically significant risk of bee mortality associated with oral exposure to DCH was observed. DCH is also known to be significantly more stable than fumagillin in honey under a variety of temperature conditions, both in the presence and absence of light. The presence of DCH in the hive is therefore a potential concern for bee health and also for food safety

Worldwide Diaspora of Aethina tumida (Coleoptera: Nitidulidae), a Nest Parasite of Honey Bees

Native to sub-Saharan Africa, Aethina tumida Murray (Coleoptera: Nitidulidae) is now an invasive pest of honey bee, Apis mellifera L., colonies in Australia and North America. Knowledge about the introduction(s) of this beetle from Africa into and among the current ranges will elucidate pest populations and invasion pathways and contribute to knowledge of how a parasite expands in new populations. We examined genetic variation in adult beetle samples from the United States, Australia, Canada, and Africa by sequencing a 912-base pair region of the mitochondrial DNA cytochrome c oxidase subunit I gene and screening 10 informative microsatellite loci. One Canadian introduction of small hive beetles can be traced to Australia, whereas the second introduction seems to have come from the United States. Beetles now resident in Australia were of a different African origin than were beetles in North America. North American beetles did not show covariance between two mitochondrial haplotypes and their microsatellite frequencies, suggesting that these beetles have a shared source despite having initial genetic structure within their introduced range. Excellent dispersal of beetles, aided in some cases by migratory beekeeping and the bee trade, seems to lead to panmixis in the introduced populations as well as in Afric

Managed honey bee colony losses in Canada, China, Europe, Israel and Turkey, for the winters of 2008-9 and 1009-10

In 2008 the COLOSS network was formed by honey bee experts from Europe and the USA. The primary objectives set by this scientific network were to explain and to prevent large scale losses of honey bee (Apis mellifera) colonies. In June 2008 COLOSS obtained four years support from the European Union from COST and was designated as COST Action FA0803 – COLOSS (Prevention of honey bee COlony LOSSes). To enable the comparison of loss data between participating countries, a standardized COLOSS questionnaire was developed. Using this questionnaire information on honey bee losses has been collected over two years. Survey data presented in this study were gathered in 2009 from 12 countries and in 2010 from 24 countries. Mean honey bee losses in Europe varied widely, between 7-22% over the 2008-9 winter and between 7-30% over the 2009-10 winter. An important finding is that for all countries which participated in 2008-9, winter losses in 2009-10 were found to be substantially higher. In 2009-10, winter losses in South East Europe were at such a low level that the factors causing the losses in other parts of Europe were absent, or at a level which did not affect colony survival. The five provinces of China, which were included in 2009-10, showed very low mean (4%) A. mellifera winter losses. In six Canadian provinces, mean winter losses in 2010 varied between 16-25%, losses in Nova Scotia (40%) being exceptionally high. In most countries and in both monitoring years, hobbyist beekeepers (1-50 colonies) experienced higher losses than practitioners with intermediate beekeeping operations (51-500 colonies). This relationship between scale of beekeeping and extent of losses effect was also observed in 2009-10, but was less pronounced. In Belgium, Italy, the Netherlands and Poland, 2008-9 mean winter losses for beekeepers who reported ‘disappeared’ colonies were significantly higher compared to mean winter losses of beekeepers who did not report ‘disappeared’ colonies. Mean 2008-9 winter losses for those beekeepers in the Netherlands who reported symptoms similar to “Colony Collapse Disorder” (CCD), namely: 1. no dead bees in or surrounding the hive while; 2. capped brood was present, were significantly higher than mean winter losses for those beekeepers who reported ‘disappeared’ colonies without the presence of capped brood in the empty hives. In the winter of 2009-10 in the majority of participating countries, beekeepers who reported ‘disappeared’ colonies experienced higher winter losses compared with beekeepers, who experienced winter losses but did not report ‘disappeared’ colonies

Ecological Adaptation of Diverse Honey Bee (Apis mellifera) Populations

BACKGROUND: Honey bees are complex eusocial insects that provide a critical contribution to human agricultural food production. Their natural migration has selected for traits that increase fitness within geographical areas, but in parallel their domestication has selected for traits that enhance productivity and survival under local conditions. Elucidating the biochemical mechanisms of these local adaptive processes is a key goal of evolutionary biology. Proteomics provides tools unique among the major 'omics disciplines for identifying the mechanisms employed by an organism in adapting to environmental challenges. RESULTS: Through proteome profiling of adult honey bee midgut from geographically dispersed, domesticated populations combined with multiple parallel statistical treatments, the data presented here suggest some of the major cellular processes involved in adapting to different climates. These findings provide insight into the molecular underpinnings that may confer an advantage to honey bee populations. Significantly, the major energy-producing pathways of the mitochondria, the organelle most closely involved in heat production, were consistently higher in bees that had adapted to colder climates. In opposition, up-regulation of protein metabolism capacity, from biosynthesis to degradation, had been selected for in bees from warmer climates. CONCLUSIONS: Overall, our results present a proteomic interpretation of expression polymorphisms between honey bee ecotypes and provide insight into molecular aspects of local adaptation or selection with consequences for honey bee management and breeding. The implications of our findings extend beyond apiculture as they underscore the need to consider the interdependence of animal populations and their agro-ecological context

ConectCat : aplicación web : fiestas locales y otros servicios y puntos de interés en Cataluña

Aplicación web basada en mapas interactivos y timeline. Permite visualizar las fiestas locales así como otros servicios y puntos de interés de Cataluña

Pollen quality of fresh and 1-year-old single pollen diets for worker honey bees (Apis mellifera L.)

Newly-emerged honey bees were placed in cages and fed sucrose syrup and one of the following single-pollen diets: Malus domestica Borkh., Brassica campestris L., Phacelia tanacetifolia L., Melilotus officinalis (L.) Pall., Helianthus annuus L., Pinus banksiana (Lamb.), artificial supplement (Bee-Pro$^{\circledR}$) or nothing. Hypopharyngeal gland protein was determined at intervals of 0, 3, 8 and 14 days and ovary development was visually scored on day 14. The development of hypopharyngeal glands and ovaries varied with diet and, collectively, proved to be sensitive measures of protein utilization and pollen quality. For workers fed 1-year-old Phacelia pollen, protein was utilized in a differential fashion, promoting the development of ovaries over that of hypopharyngeal glands. Development of glands and ovaries was strongly correlated with the amount of protein workers consumed from pollen diets, and to a lesser extent, the crude protein content of diets. Storing pollen for 1 year by freezing did not affect gland or ovary development.Qualité de différents pollens monofloraux, frais et d'un an, comme nourriture pour les ouvrières d'abeilles domestiques (Apis mellifera L.). Des groupes de 150 abeilles naissantes ont été placées dans des cages en bois, nourries avec une solution de saccharose à 2 M et avec l'un des six pollens suivants : Malus domestica Borkh., Brassica campestris L., Phacelia tanacetifolia L., Melilotus officinalis (L.) Pall., Helianthus annuus L. et Pinus banksiana (Lamb.). Un succédané commercial de pollen, Bee-Pro$^{\circledR}$, et un régime sans pollen ont également été testés. Le pollen fourni aux abeilles encagées était soit du pollen fraîchement récolté, soit du pollen congelé à $-30~^\circ$C pendant un an et conservé dans des récipients en verre sous atmosphère réduite en oxygène. Au début de l'expérience, puis aux jours J3, J8 et J14, dix abeilles ont été prélevées dans chaque cage et leurs glandes hypopharyngiennes extraites. La teneur totale en protéines des glandes a été déterminée par le test de Bradford et utilisée comme mesure du développement et de la taille des glandes. A la fin de l'expérience (J14), 25 abeilles de chaque cage ont été disséquées et leur développement ovarien classé visuellement de 0 à 4. Le développement des glandes hypopharyngiennes et des ovaires a varié en fonction du régime et s'est comporté, dans l'ensemble, comme une mesure fiable et sensible de l'utilisation des protéines et de la qualité du pollen. Pour les ouvrières nourries avec du pollen de phacélie d'un an, les protéines ont été utilisées différemment : elles ont plus favorisé le développement des ovaires que celui des glandes hypopharyngiennes. Le développement des ovaires et des glandes était fortement corrélé avec la quantité de protéines consommées issues du pollen et, à un moindre degré, avec la teneur brute en protéines des pollens. La conservation du pollen par congélation durant un an n'a eu aucun effet sur le développement des glandes ni des ovaires. Le pollen de tournesol et le succédané Bee-Pro$^{\circledR}$ devraient être complétés par d'autres espèces de pollen lorsqu'ils sont donnés en nourrissement ; le pollen de pin devrait être évité

A tale of two parasites: Responses of honey bees infected with Nosema ceranae and Lotmaria passim

Abstract Nosema ceranae and Lotmaria passim are two commonly encountered digestive tract parasites of the honey bee that have been associated with colony losses in Canada, the United States, and Europe. Though honey bees can be co-infected with these parasites, we still lack basic information regarding how they impact bee health at the individual and colony level. Using locally-isolated parasite strains, we investigated the effect of single and co-infections of these parasites on individual honey bee survival, and their responsiveness to sucrose. Results showed that a single N. ceranae infection is more virulent than both single L. passim infections and co-infections. Honey bees singly infected with N. ceranae reached < 50% survival eight days earlier than those inoculated with L. passim alone, and four days earlier than those inoculated with both parasites. Honey bees infected with either one, or both, parasites had increased responsiveness to sucrose compared to uninfected bees, which could correspond to higher levels of hunger and increased energetic stress. Together, these findings suggest that N. ceranae and L. passim pose threats to bee health, and that the beekeeping industry should monitor for both parasites in an effort correlate pathogen status with changes in colony-level productivity and survival

The innate immune and systemic response in honey bees to a bacterial pathogen, Paenibacillus larvae

Background. There is a major paradox in our understanding of honey bee immunity: the high population density in a bee colony implies a high rate of disease transmission among individuals, yet bees are predicted to express only two-thirds as many immunity genes as solitary insects, e.g., mosquito or fruit fly. This suggests that the immune response in bees is subdued in favor of social immunity, yet some specific immune factors are up-regulated in response to infection. To explore the response to infection more broadly, we employ mass spectrometry-based proteomics in a quantitative analysis of honey bee larvae infected with the bacterium Paenibacillus larvae. Newly-eclosed bee larvae, in the second stage of their life cycle, are susceptible to this infection, but become progressively more resistant with age. We used this host-pathogen system to probe not only the role of the immune system in responding to a highly evolved infection, but also what other mechanisms might be employed in response to infection. Results Using quantitative proteomics, we compared the hemolymph (insect blood) of five-day old healthy and infected honey bee larvae and found a strong up-regulation of some metabolic enzymes and chaperones, while royal jelly (food) and energy storage proteins were down-regulated. We also observed increased levels of the immune factors prophenoloxidase (proPO), lysozyme and the antimicrobial peptide hymenoptaecin. Furthermore, mass spectrometry evidence suggests that healthy larvae have significant levels of catalytically inactive proPO in the hemolymph that is proteolytically activated upon infection. Phenoloxidase (PO) enzyme activity was undetectable in one or two-day-old larvae and increased dramatically thereafter, paralleling very closely the age-related ability of larvae to resist infection. Conclusion We propose a model for the host response to infection where energy stores and metabolic enzymes are regulated in concert with direct defensive measures, such as the massive enhancement of PO activity.Biochemistry and Molecular Biology, Department ofMedicine, Faculty ofScience, Faculty ofOther UBCNon UBCReviewedFacult