The loss of managed honey bee colonies, resulting from their unintentional exposure to pesticides, is a topic of concern for the agricultural and apicultural industry. Current methods for reducing pesticide exposure to bees involve the application of pesticides before crop bloom or in the evening when foraging bees are less likely to be exposed to these applications. There is an urgent need for additional protection procedures to reduce the annual losses of managed bee colonies. Another method for protecting these pollinators is the use of chemical deterrents to reduce the interaction times of foraging bees with pesticide-treated crops. Historically, insect repellents (IRs) have been used to prevent the spread of deadly human diseases by arthropod vectors. However, it has been shown that bees can be repelled from pesticide-treated crops using DEET and bee pheromonal compounds. Here, I report the toxicological and deterrent effects of bee pheromonal compounds, as well as the deterrent effects of heterocyclic amines (HCAs) on bees. The results of this study indicate that the bee pheromonal compounds, at 8, 20, 60 and 100% concentrations, are toxic to bees and inhibit the feeding of bees within a confined space. Additionally, the pheromonal compounds and the HCAs are as efficacious as DEET in deterring bees from treated food sources. The HCA piperidine was observed to effectively deter bee foragers from a sugar feeder in a high-tunnel experiment as well as from melon flowers and knapweed in field experiments. Electroantennogram recordings were conducted to verify an olfactory response of the bees to the tested compounds. Pheromonal compounds were readily detected by bee antennae; whereas, the HCAs did not elicit significant responses in the bee antennae. These data suggest that bee pheromonal compounds, as well as HCAs, may serve as candidates for the further investigation as repellents to protect bees from unintentional pesticide exposures. / Ph. D.

The decline of honey bee (Apis mellifera) colony numbers in recent years presents an economic and ecological threat to agriculture. One outstanding threat to honey bees is the unintended exposure to agricultural pesticides. Previous studies report that acute exposures to the common-use herbicide atrazine elicit oxidative stress in non-target insects; however, little information is currently available on the exposure risk of atrazine to honey bees. This project examined biochemical and molecular oxidative stress response markers of honey bees following laboratory and field treatments of atrazine. Laboratory experiments were conducted with honey bees exposed to increasing concentrations of atrazine for 24 h whereas hive experiments were conducted with bees exposed to one sub-lethal concentration of atrazine for 28 d. The overall antioxidant enzyme activities of atrazine-treated honey bees were decreased compared to the untreated honey bees in both the laboratory and hive experiments. After exposure to atrazine in the laboratory and field, semi-quantitative RT-PCR analysis of antioxidant-encoding genes reveals the differential expression of genes in atrazine-treated bees that are important for oxidative stress tolerance in the laboratory and field experiments. Here, we provide evidence that the laboratory and hive exposure of honey bees to the common-use herbicide atrazine results in oxidative stress responses that can compromise the health of bee colonies. The data will be discussed with regard to the protection of these pollinators against the untended exposure of agricultural pesticides. / Master of Science in Life Sciences

The honey bee, Apis mellifera, provides about $15 billion USD in crop value each year in the U.S. alone in the form of pollination services. Since 2006, commercial beekeepers have reported an average annual overwintering loss of about 28.6% of all managed colonies. There are many factors that are thought to contribute to colony loss including bee-specific pests (e.g. the Varroa destructor mite), bee-specific pathogens (e.g. Nosema fungus), modern beekeeping practices, diminished genetic variability, poor queens, climate change, and exposure to agricultural pesticides. While not the single cause of colony loss, the neonicotinoid insecticides elicit sublethal effects to honey bees that could increase their sensitivities to other stressors that affect colony health. Previous studies found that honey bees have differential sensitivities to the neonicotinoid insecticide imidacloprid, which suggest a mechanism of tolerance to the insecticide in certain colonies. In this study, I examined the imidacloprid sensitivity of honey bees collected from different colonies. After determining a range of LC50 values in the tested colonies, I examined the metabolic detoxification activities of honey bees collected from two colonies that represented the highest and lowest LC50 values, between which there was a 36-fold difference in their LC50 values. I discovered that of the three main families of metabolic detoxification enzymes, general esterases, cytochrome P450 monooxygenases, and glutathione S-transferases (GSTs), a reduction of GST activity with diethyl maleate (DEM) significantly increased imidacloprid-mediated mortality to the honey bees. A comparative analysis of GST kinetic activity from imidacloprid-susceptible and -insensitive honey bees revealed a lower bimolecular inhibition rate constant (ki) for imidacloprid-insensitive individuals (5.07 ± 0.098 nmol/min/mg protein) compared to the imidacloprid-sensitive honey bees (17.23 ± 1.235 nmol/min/mg protein). The IC50 of DEM estimated for bees from each colony showed that the imidacloprid-susceptible honey bees possess a higher IC50 (10 μM) than that of the tolerant honey bees (3 μM). These data suggest that the GSTs in the imidacloprid-tolerant honey bees might be a more efficient detoxification mechanism for the conjugation and elimination of imidacloprid, or imidacloprid metabolites, compared to that of imidacloprid-susceptible honey bees. Therefore, I hypothesize that the differences in metabolic detoxification enzyme activities of honey bees collected from different colonies can result in the differential toxicities of honey bees exposed to neonicotinoid insecticides, such as imidacloprid. However, a thorough examination of imidacloprid detoxification in honey bees is warranted to confirm this hypothesis. / Master of Science in Life Sciences

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Over 270 million people play soccer worldwide, and its popularity grows every day. In team sport exercise, fatigue may result from numerous factors including limited fuel, depleted energy stores and production of compounds that promote an inflammatory response. While inflammation is an essential mechanism for repairing damaged muscle tissue with exercise, prolonged inflammation leads to increased production of reactive oxygen species that can damage cell membranes, muscle, and signaling proteins. To prevent this response and improve performance, athletes are increasingly looking to nutritional interventions. Carbohydrate and antioxidant supplementation have both shown evidence of producing an ergogenic effect and attenuating inflammation and oxidative stress with prolonged endurance exercise. Less is known about how these interventions may influence intermittent, high-intensity exercise characteristic of soccer. In particular, this exercise presents a unique challenge in that opportunities for nutrient intake are limited to pre-game and half-time. In our first study, we had 10 male collegiate soccer players perform a 90-min. soccer-simulation test, that we developed, which was followed by a progressive shuttle run (PSR) test to exhaustion. They consumed a honey-sweetened beverage (H), a sports drink (S), or a placebo (P) before and half-way through the protocol. Both H and S provided 1.0 g·kg⁻¹ carbohydrate and ~17.6 mL·kg⁻¹ total volume for each trial. Overall, the test resulted in increased fatigue and production of inflammatory markers and antioxidant capacity. There was no significant difference between treatments for any performance measure. Mean times for a high intensity run and rating of perceived exertion increased with time, and there was an overall decrease in PSR time compared to baseline (-22.9%). There was a rise in glucose (15.6%), IL-6 (548%), IL-1ra, IL-10 (514%) and ORAC (15%) post-test but no change in cortisol. Insulin was significantly lower by 1 h-post. IL-1ra levels increased post-test for H (25.8%), S (65.5%), and P (63.9%), but the change for H was less than the other treatments. No treatment effects for the other blood measures were observed. The lack of an ergogenic effect of carbohydrate on soccer performance calls into question the benefit of supplementation at a frequency typical of a regulation soccer match in highly trained athletes with adequate energy stores. Since acute carbohydrate ingestion in the first study did not attenuate some markers of inflammation (e.g. IL-6), we chose to focus on an alternative theory for the rise in inflammatory markers with strenuous exercise in our second study. One aspect of soccer, repeated sprinting, results in increased ROS production partially through the activation of the enzyme xanthine oxidase (XO). Quercetin, a flavonol in plants that has shown some ergogenic effects with endurance exercise, inhibits XO in vitro. The effect of quercetin on team sport exercise had not been studied. We gave recreationally active males a commercial sports drink (S) or S + 500 mg of quercetin (Q) 2x/d for 1 wk prior to a repeated sprint test (RST). Sprint times increased (5.9%) for both treatments as did plasma XO activity (47%), IL-6 (77%), and uric acid (25%) from pre-test to post-test. Q supplementation did not attenuate plasma XO activity or IL-6 and actually increased one calculated index of fatigue, percent fatigue decrement (5.1%- Q and 3.8%- P). These findings add to the growing body of literature that quercetin supplementation does not attenuate exercise-induced inflammation and oxidative stress in vivo. Collectively, this research has practical implications for sports drink companies who are exploring the use of flavonoid compounds in product formulation. Specifically, they should reconsider adding quercetin to their beverages if they are marketing to team sport athletes. Also, soccer players should be made aware that, at ingestion frequencies typical of a soccer match, they may not expect a significant performance benefit from acute carbohydrate supplementation. / Ph. D.

BACKGROUND: The honey bee is an important model system for increasing understanding of molecular and neural mechanisms underlying social behaviors relevant to the agricultural industry and basic science. The western honey bee, Apis mellifera, has served as a model species, and its genome sequence has been published. In contrast, the genome of the Asian honey bee, Apis cerana, has not yet been sequenced. A. cerana has been raised in Asian countries for thousands of years and has brought considerable economic benefits to the apicultural industry. A cerana has divergent biological traits compared to A. mellifera and it has played a key role in maintaining biodiversity in eastern and southern Asia. Here we report the first whole genome sequence of A. cerana. RESULTS: Using de novo assembly methods, we produced a 238 Mbp draft of the A. cerana genome and generated 10,651 genes. A.cerana-specific genes were analyzed to better understand the novel characteristics of this honey bee species. Seventy-two percent of the A. cerana-specific genes had more than one GO term, and 1,696 enzymes were categorized into 125 pathways. Genes involved in chemoreception and immunity were carefully identified and compared to those from other sequenced insect models. These included 10 gustatory receptors, 119 odorant receptors, 10 ionotropic receptors, and 160 immune-related genes. CONCLUSIONS: This first report of the whole genome sequence of A. cerana provides resources for comparative sociogenomics, especially in the field of social insect communication. These important tools will contribute to a better understanding of the complex behaviors and natural biology of the Asian honey bee and to anticipate its future evolutionary trajectory.

Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: The aim of this study was to investigate the phylogeographic structuring of the honey badger, Mellivora capensis, a highly mobile medium sized carnivore with an extensive distribution throughout sub-Saharan Africa extending into the Middle East and India. Particular focus was placed on providing preliminary data potentially useful for the development of translocation policies for this species in southern Africa. Where possible, genetic results were also compared with current trinomial designations to determine whether subspecies status given to geographical groupings was supported by the genetic data. Mitochondrial control region sequence data was obtained for most a selection of specimen’s available while nuclear microsatellite variation was determined for a subset of individuals where there were sufficient sample sizes available. Phylogeographic structuring of the maternal mitochondrial lineage was initially obscured by the coamplification of a closely related numt. To overcome co-amplification, the numt was identified and mtDNA specific primers were designed. Mitochondrial DNA results are based on the most variable 230 bp of the control region (sequenced for 78 individuals) while five polymorphic nuclear microsatellite markers were scored (for 55 individuals). Analysis, employing both nuclear and mitochondrial data, showed that although a pattern of isolation by distance can be detected, there was evidence for the presence of phylogeographic structuring between eastern and southern Africa. This could be interpreted as due to vicariance, probably associated by rifting and climatic occilations during the Pleistocene. Analyses support the identification of distinct management units for eastern and southern African populations although some evidence exists for secondary introgression between these two regions. Following this, we recommend that translocations between these broad geographic areas should be avoided. Within these geographic areas, because of a general pattern of isolation by distance, we recommend that individuals for translocations come from geographically proximate populations. In some instances, phylogeographic structuring is concordant with subspecies designations but additional sampling will be needed to make any firm taxonomic conclusions. / AFRIKAANSE OPSOMMING: Die doelwit van hierdie studie was om die filogeografiese struktuur van die ratel, Mellivora capensis, ‘n hoogs bewegende medium groot karnivoor met ‘n wydverspreide distribusie deur sub-Sahara Afrika wat strek tot in die Midde Ooste en India, te bepaal. Spesifieke fokus is geplaas op die voorsiening van preliminêre data potensieel bruikbaar vir dir ontwikkeling van verplasing strategieë vir hierdie spesie in suidelike Afrika. Genetiese resultate is, waar moontlik, vergelyk met huidige drieledige kategorieë om te bepaal of subspesies ondersteun word deur die genetiese data. Mitochondriale ‘control region’ DNS volgorde data was verkry vir die meeste van die monsters beskikbaar en kern mikrosatelliet variasie was bepaal vir ‘n gedeelte van individue waar voldoende monster groottes beskikbaar was. Filogeografiese strukturering van die materne mitochondriale merker was oorspronklik versteek deur die ko-amplifikasie van ‘n naby verwante ‘numt’. Om die ko-amplifikasie te oorkom is die ‘numt’ geïdentifiseer en mtDNS spesifieke voorvoerders is ontwerp. Mitochondriale DNS resultate is gebaseer op die mees veranderlike 230 bp van die ‘control region’ (waar die DNS volgorde vir 78 individue bepaal is) en vyf polimorfiese kern mikrosatelliet merkers (in 55 individue). Analises, wat gebruik maak van kern en mitochondriale data, toon wel ‘n patroon van isolasie deur afstand, maar ook ‘n duidelike sigbare filogeograpfiese strukturering tussen oostelike en suidelike Afrika. Hierdie is geïnterpreteer as vikariansie, heel waarskynlik ge-assosieer deur berg verskuiwings en klimaatsveranderinge deur die Pleistocene. Analises ondersteun die identifikasie van definitiewe verkillende bestuurseenhede vir oostelike en suidelike Afrika maar sekere bewyse bestaan dat sekondêre introgressie tussen streke bestaan. Dit word aanbeveel dat translokasies tussen hierdie geografiese areas voorkom moet word. Binne geografiese areas, as gevolg van ‘n algemene patroon van isolasie deur afstand, is dit aanbeveel dat individue vir verplasing van nabygeleë populasies moet wees. In sommige gevalle het filogeografiese strukturering ooreen gestem met subspesies kategorieë, maar verdere materiaal is nodig voor definitiewe taksonomiese besluite geneem kan word.

A study of the life history and secondary production of Caenis latipennis, a caenid mayfly, was conducted on Honey Creek, OK. from August 1999 through September 2000. The first instar nymph was described. Nymphs were separated into five development classes. Laboratory egg and nymph development rates, emergence, fecundity, voltinism, and secondary production were analyzed. C. latipennis eggs and nymphs take 132 and 1709 degree days to develop. C. latipennis had an extended emergence with five peaks. Females emerged, molted, mated, and oviposited in an estimated 37 minutes. Mean fecundity was 888.4 ± 291.9 eggs per individual (range 239 -1576). C. latipennis exhibited a multivoltine life cycle with four overlapping generations. Secondary production was 6,052.57 mg/m2/yr.

The topic of this diploma thesis is to evaluate the impact of grazing on the quality of bee honey. The theoretical part focuses on the characteristics of the individual kinds of honey and their different compositions. The fundamental physical and chemical requirements for honey are described there, including a sensory requirement, which indicates Public Notice No. 76/2003 Coll. The practical part contains the physico-chemical analysis itself, according to the Harmonised methods of the European Honey. The two fundamental kinds of honey were evaluated, i.e. blossom and honeydew honey. Each type of honey was represented by 20 samples. Subsequently, the following parameters were monitored: water content, acidity, pH, electrical conductivity, content of water-insoluble substances and also the test for the evidence of damage of honey structure by starch syrup was done. The comparison of the samples shows that the different types of honey vary mostly in the parameter of electrical conductivity. The final results show that the different bee grazing does not impact the quality of honey.