Publications by authors named "Richard D Fell"

Laboratory experiments have advanced our understanding of honey bee (Apis mellifera) responses to environmental factors, but removal from the hive environment may also impact physiology. To examine whether the laboratory environment alters the honey bee gut bacterial community and immune responses, we compared bacterial community structure (based on amplicon sequence variant relative abundance), total bacterial abundance, and immune enzyme (phenoloxidase and glucose oxidase) activity of cohort honey bee workers kept under laboratory and hive conditions. Workers housed in the laboratory showed differences in the relative abundance of their core gut taxa, an increase in total gut bacterial abundance, and reduced phenoloxidase activity, compared to bees housed in hives.

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Chlorothalonil is a broad spectrum chloronitrile fungicide that has been identified as one of the most common pesticide contaminants found in managed honey bees (Hymenoptera: Apidae: Apis mellifera L.), their food stores, and the hive environment. While not acutely toxic to honey bees, several studies have identified potential sublethal effects, especially in larvae, but comprehensive information regarding the impact of chlorothalonil on adults is lacking.

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Large-scale honey bee colony loss threatens pollination services throughout the United States. An increase in anthropogenic pressure may influence the exposure of hives to household and agricultural pesticides. The objective of this survey was to provide an assessment of the risk of exposure to commonly used pesticides to honey bee colonies in Virginia in relation to land use.

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The honey bee is a widely managed crop pollinator that provides the agricultural industry with the sustainability and economic viability needed to satisfy the food and fiber needs of our society. Excessive exposure to apicultural pesticides is one of many factors that has been implicated in the reduced number of managed bee colonies available for crop pollination services. The goal of this study was to assess the impact of exposure to commonly used, beekeeper-applied apicultural acaricides on established biochemical indicators of bee nutrition and immunity, as well as morphological indicators of growth and development.

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Neonicotinoid insecticide use has been suggested as a cause of honey bee colony decline; however, detection rates and concentrations of neonicotinoid insecticide residues in field-collected honey bees have been low. We collected honey bee and beebread samples from apiaries in agricultural, developed, and undeveloped areas during 2 years in Virginia to assess whether landscape type or county pesticide use was predictive of honey bee colony exposure to neonicotinoid insecticides. Trace concentrations of the neonicotinoid imidacloprid were detected in honey bees (3 of 84 samples, 2.

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Honey bee, Apis mellifera (L.; Hymenoptera: Apidae), populations are in decline and their losses pose a serious threat for crop pollination and food production. The specific causes of these losses are believed to be multifactorial.

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Honey bee colony loss continues to be an issue and no factor has been singled out as to the cause. In this study, we sought to determine whether two beekeeper-applied pesticide products, tau-fluvalinate and Fumagilin-B(®), and one agrochemical, chlorothalonil, impact the nutrient levels in honey bee workers in a natural colony environment. Treatments were performed in-hive and at three different periods (fall, spring, and summer) over the course of one year.

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Queens are the primary female reproductive individuals in honey bee colonies and, while they are generally free from Nosema ceranae infection, they are nevertheless susceptible. We sought to determine whether queens are naturally infected by N. ceranae, as these infections could be a factor in the rapid spread of this parasite.

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Since 2006, beekeepers have reported increased losses of Apis mellifera colonies, and one factor that has been potentially implicated in these losses is the microsporidian Nosema ceranae. Since N. ceranae is a fairly recently discovered parasite, there is little knowledge of the variation in infection levels among individual workers within a colony.

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Nosema ceranae is a microsporidian parasite of the European honey bee, Apis mellifera, that is found worldwide and in multiple Apis spp.; however, little is known about the effects of N. ceranae on A.

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Nosema ceranae is a microsporidian intracellular parasite of honey bees, Apis mellifera. Previously Nosema apis was thought to be the only cause of nosemosis, but it has recently been proposed that N. ceranae is displacing N.

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Nosema ceranae is a recently described pathogen of Apis mellifera and Apis cerana. Relatively little is known about the distribution or prevalence of N. ceranae in the United States.

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Miticide residues in Virginia honeys.

Bull Environ Contam Toxicol

December 2009

Fifty honey samples from Virginia USA were analyzed for the presence of fluvalinate and coumaphos residues. Samples were collected from hives and from bottled honey provided by beekeepers. No coumaphos or fluvalinate residues above the limit of quantification (0.

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We conducted research to examine the potential impacts ofcoumaphos, fluvalinate, and Apilife VAR (Thymol) on drone honey bee, Apis mellifera L. (Hymenoptera: Apidae), sperm viability over time. Drones were reared in colonies that had been treated with each miticide by using the dose recommended on the label.

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The effects of antemortem ingestion of ethanol by domestic pigs, Sus scrofa L., on postmortem insect successional patterns and the development of Phormia regina (Meigen) were studied during summer 2003 in Blacksburg, VA. Insect samples were collected from the carcasses of ethanol-treated and untreated pigs for 10 d postmortem during two successional studies.

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Successional patterns of insect fauna on pig carcasses were studied in southwest Virginia. The objective was to identify and qualitatively assess the major taxa of forensic importance in this region. Studies were conducted in spring and summer 2001 and 2002, and fall 2002.

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Studies of carrion-insect succession on domestic pig, Sus scrofa L., were conducted in the spring and summer of 2001 and 2002 in Blacksburg, VA, to identify and analyze the successional patterns of the taxa of forensic importance in southwest Virginia. Forty-seven insect taxa were collected in the spring.

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