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Anders Lindstrom - One of the best experts on this subject based on the ideXlab platform.
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distribution of paenibacillus larvae spores among adult honey bees apis mellifera and the relationship with clinical symptoms of american foulbrood
Microbial Ecology, 2008Co-Authors: Anders LindstromAbstract:Knowledge of the distribution of Paenibacillus larvae spores, the causative agent of American foulbrood (AFB), among individual adult honey bees is crucial for determining the appropriate number of adult bees to include in Apiary composite samples when screening for diseased colonies. To study spore distribution at the individual bee level, 500 honey bees were collected from different parts of eight clinically diseased colonies and individually analyzed for P. larvae. From the brood chamber and from the super, bees were randomly collected and individually put in Eppendorf vials. The samples were frozen as soon as possible after collection. Concurrently with sampling, each colony was visually inspected for clinical symptoms of AFB. The number of clinically diseased cells in the colony was visually estimated. All samples were cultured in the laboratory for P. larvae. The results demonstrate that the spores are not randomly distributed among the bees; some bees have much higher spore loads than others. It is also clear that as the proportion of contaminated bees increase, the number of spores from each positive bee also increases. The data also demonstrated a relationship between the number of clinically diseased cells and the proportion of positive bees in individual colonies. This relationship was used to develop a mathematical formula for estimating the minimum number of bees in a sample to detect clinical disease. The formula takes into account the size of the Apiary and the degree of certainty with which one aims to discover clinical symptoms. Calculations using the formula suggest that adult bee samples at the colony level will detect light AFB infections with a high probability. However, the skewed spore distribution of the adult bees makes composite sampling at the Apiary level more problematic, if the aim of the sampling is to locate lightly infected individual colonies within apiaries. The results suggest that false-negative culturing results from composite samples of adult bees from individual colonies with clinical symptoms of AFB are highly improbable. However, if single colonies have light infections in large apiaries, the dilution effect from uncontaminated bees from healthy colonies on the positive bees from diseased colonies may yield false-negative results at the Apiary level.
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sampling of adult bees for detection of american foulbrood paenibacillus larvae subsp larvae spores in honey bee apis mellifera colonies
Journal of Apicultural Research, 2005Co-Authors: Anders Lindstrom, Ingemar FriesAbstract:SUMMARYFifty-nine apiaries with a total of 489 honey bee colonies belonging to a beekeeping operation in central Sweden with a previous history of American foulbrood (AFB) were inspected. For each colony the clinical disease status was visually inspected and the number of brood cells clinically diseased by AFB estimated. From 94 of these colonies, individual samples of > 100 live honey bees from the brood chamber and supers were collected. Two composite samples consisting of > 100 adult bees from each individual colony in each inspected Apiary were also taken from (1) all brood chambers and (2) all supers, respectively. Samples were taken on both the individual colony level and the Apiary level and analysed for presence of Paenibacillus larvae subsp. larvae by culturing. Spores were found in 100% (n = 21) of the bee samples from clinically diseased colonies and in 77% of the supers, and 82% of the brood chambers in colonies without clinical symptoms (n = 73). On the Apiary level, 100% of the samples from ...
Peter J Neumann - One of the best experts on this subject based on the ideXlab platform.
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cold ambient temperature promotes nosema spp intensity in honey bees apis mellifera
Insects, 2017Co-Authors: Gina Retschnig, Geoffrey R Williams, Annette Schneeberger, Peter J NeumannAbstract:Interactions between parasites and environmental factors have been implicated in the loss of managed Western honey bee (=HB, Apis mellifera) colonies. Although laboratory data suggest that cold temperature may limit the spread of Nosema ceranae, an invasive species and now ubiquitous endoparasite of Western HBs, the impact of weather conditions on the distribution of this microsporidian in the field is poorly understood. Here, we conducted a survey for Nosema spp. using 18 Swiss apiaries (four colonies per Apiary) over a period of up to 18 months. Samples consisting of 60 workers were collected monthly from each colony to estimate Nosema spp. intensity, i.e., the number of spores in positive samples using microscopy. Ambient Apiary temperature was measured daily to estimate the proportion of days enabling HB flight (>10 °C at midday). The results show that Nosema spp. intensities were negatively correlated with the proportion of days enabling HB flight, thereby suggesting a significant and unexpected positive impact of cold ambient temperature on intensities, probably via regulation of defecation opportunities for infected hosts.
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queen mating frequency in different types of honey bee mating apiaries
Journal of Apicultural Research, 1999Co-Authors: Peter J Neumann, Robin F A Moritz, Job Van PraaghAbstract:SUMMARYSamples of worker honey bees (Apis mellifera carnica) were taken from 29 queenright honey bee colonies. The queens of these colonies were mated at two island mating apiaries (n = 7 and n = 6), two lowland apiaries (n = 6 and n = 4), a highland mating Apiary (n = 3) and on one isolated high-mountain Apiary (n = 3). Genotypes of individual workers (n = 1055) were determined using four DNA microsatellite loci and the observed (no) and effective (me) numbers of matings were estimated from the worker offspring. The observed number of matings per queen ranged from 6 to 24 (me = 4.6 to 31.1). Significant differences (P < 0.05) were found between the number of matings of queens at island and mainland mating apiaries. An average of no = 13.0 ± 1.1 (me = 11.8 ± 1.2) matings for queens at the two islands and an average of no = 18.1 ± 1.1 (me = 20.4 ± 1.7) for queens at the mainland apiaries were observed. No differences in mating frequency were observed between the queens at the island locations and among the...
Ingemar Fries - One of the best experts on this subject based on the ideXlab platform.
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sampling of adult bees for detection of american foulbrood paenibacillus larvae subsp larvae spores in honey bee apis mellifera colonies
Journal of Apicultural Research, 2005Co-Authors: Anders Lindstrom, Ingemar FriesAbstract:SUMMARYFifty-nine apiaries with a total of 489 honey bee colonies belonging to a beekeeping operation in central Sweden with a previous history of American foulbrood (AFB) were inspected. For each colony the clinical disease status was visually inspected and the number of brood cells clinically diseased by AFB estimated. From 94 of these colonies, individual samples of > 100 live honey bees from the brood chamber and supers were collected. Two composite samples consisting of > 100 adult bees from each individual colony in each inspected Apiary were also taken from (1) all brood chambers and (2) all supers, respectively. Samples were taken on both the individual colony level and the Apiary level and analysed for presence of Paenibacillus larvae subsp. larvae by culturing. Spores were found in 100% (n = 21) of the bee samples from clinically diseased colonies and in 77% of the supers, and 82% of the brood chambers in colonies without clinical symptoms (n = 73). On the Apiary level, 100% of the samples from ...
Silvio Erler - One of the best experts on this subject based on the ideXlab platform.
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high resolution maps of swiss apiaries and their applicability to study spatial distribution of bacterial honey bee brood diseases
PeerJ, 2019Co-Authors: Raphael S Von Buren, Nikolaus J Kuhn, Bernadette Oehen, Silvio ErlerAbstract:Honey bees directly affect and are influenced by their local environment, in terms of food sources, pollinator densities, pathogen and toxin exposure and climate. Currently, there is a lack of studies analyzing these data with Geographic Information Systems (GIS) to investigate spatial relationships with the environment. Particularly for intercolonial pathogen transmission, it is known that the likelihood of a healthy colony to become infested (e.g., Varroosis) or infected (e.g., American foulbrood-AFB, European foulbrood-EFB) increases with higher colony density. Whether these transmission paths can actually be asserted at Apiary level is largely unknown. Here, we unraveled spatial distribution and high-resolution density of apiaries and bacterial honey bee brood diseases in Switzerland based on available GIS data. Switzerland as `model country' offers the unique opportunity to get Apiary data since 2010 owing to compulsory registration for every beekeeper. Further, both destructive bee brood diseases (AFB and EFB) are legally notifiable in Switzerland, and EFB has an epizootic character for the last decades. As governmental data sets have to be ameliorated, raw data from the cantonal agricultural or veterinary offices have been included. We found a mean density of 0.56 apiaries per km2, and high resolution spatial analyzes showed strong correlation between density of apiaries and human population density as well as agricultural landscape type. Concerning two bacterial bee brood diseases (AFB, EFB), no significant correlation was detectable with density of apiaries on cantonal level, though a high correlation of EFB cases and Apiary density became obvious on higher resolution (district level). Hence, Swiss EFB epizootics seem to have benefited from high Apiary densities, promoting the transmission of pathogens by adult bees. The GIS-based method presented here, might also be useful for other bee diseases, anthropogenic or environmental factors affecting bee colonies.
Marla Spivak - One of the best experts on this subject based on the ideXlab platform.
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Honey Bee Exposure to Pesticides: A Four-Year Nationwide Study
Insects, 2019Co-Authors: Nancy Ostiguy, Marla Spivak, Frank Drummond, Kate Aronstein, Brian D. Eitzer, James D. Ellis, Walter S. SheppardAbstract:Pollinators, including honey bees, are responsible for the successful reproduction of more than 87% of flowering plant species: they are thus vital to ecosystem health and agricultural services world-wide. To investigate honey bee exposure to pesticides, 168 pollen samples and 142 wax comb samples were collected from colonies within six stationary apiaries in six U.S. states. These samples were analyzed for evidence of pesticides. Samples were taken bi-weekly when each colony was active. Each Apiary included thirty colonies, of which five randomly chosen colonies in each Apiary were sampled for pollen. The pollen samples were separately pooled by Apiary. There were a total of 714 detections in the collected pollen and 1008 detections in collected wax. A total of 91 different compounds were detected: of these, 79 different pesticides and metabolites were observed in the pollen and 56 were observed in the wax. In all years, insecticides were detected more frequently than were fungicides or herbicides: one third of the detected pesticides were found only in pollen. The mean (standard deviation (SD)) number of detections per pooled pollen sample varied by location from 1.1 (1.1) to 8.7 (2.1). Ten different modes of action were found across all four years and nine additional modes of action occurred in only one year. If synergy in toxicological response is a function of simultaneous occurrence of multiple distinct modes of action, then a high frequency of potential synergies was found in pollen and wax-comb samples. Because only pooled pollen samples were obtained from each Apiary, and these from only five colonies per Apiary per year, more data are needed to adequately evaluate the differences in pesticide exposure risk to honey bees among colonies in the same Apiary and by year and location.
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practical sampling plans for varroa destructor acari varroidae in apis mellifera hymenoptera apidae colonies and apiaries
Journal of Economic Entomology, 2010Co-Authors: Roger D Moon, Eric C Burkness, William D. Hutchison, Marla SpivakAbstract:The parasitic mite Varroa destructor Anderson & Trueman (Acari: Varroidae) is arguably the most detrimental pest of the European-derived honey bee, Apis mellifera L. Unfortunately, beekeepers lack a standardized sampling plan to make informed treatment decisions. Based on data from 31 commercial apiaries, we developed sampling plans for use by beekeepers and researchers to estimate the density of mites in individual colonies or whole apiaries. Beekeepers can estimate a colony's mite density with chosen level of precision by dislodging mites from ≈300 adult bees taken from one brood box frame in the colony, and they can extrapolate to mite density on a colony's adults and pupae combined by doubling the number of mites on adults. For sampling whole apiaries, beekeepers can repeat the process in each of n = 8 colonies, regardless of Apiary size. Researchers desiring greater precision can estimate mite density in an individual colony by examining three, 300-bee sample units. Extrapolation to density on adults and pupae may require independent estimates of numbers of adults, of pupae, and of their respective mite densities. Researchers can estimate Apiary-level mite density by taking one 300-bee sample unit per colony, but should do so from a variable number of colonies, depending on Apiary size. These practical sampling plans will allow beekeepers and researchers to quantify mite infestation levels and enhance understanding and management of V. destructor.
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performance of hygienic honey bee colonies in a commercial Apiary
Apidologie, 1998Co-Authors: Marla Spivak, Gary S ReuterAbstract:Colonies with naturally mated queens from a hygienic line of Italian honey bees (Apis mellifera ligustica) were compared to colonies from a commercial line of Italian bees not selected for hygienic behavior. The following characteristics were compared: rate of removal of freeze-killed brood; amount of chalkbrood; incidence of American foulbrood; honey produc- tion; and the number of mites, Varroa jacobsoni, on adult bees. The hygienic colonies removed significantly more freeze-killed brood than the commercial colonies, had significantly less chalk- brood, had no American foulbrood, and produced significantly more honey than the commercial colonies. Estimates of the number of Varroa mites on adult bees indicated that the hygienic colonies had fewer mites than the commercial colonies in three of four apiaries. In previous stu- dies on the relation between hygienic behavior and resistance to diseases and mites, the test colonies contained instrumentally inseminated queens. This is the first study to evaluate hygienic stock in large field colonies with naturally mated queens. © Inra/DIB/AGIB/Elsevier, Paris