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1
Veerkamp, Honna M. "Honeybee Collectives." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1671.
Testo completoAbstract (sommario):
This paper contextualizes my MFA thesis exhibition Honeybee Collectives, exploring the themes of affective interspecies relationships, human community building, expanded cinema, and socially engaged art. Honeybee Collectives is a site-specific multimedia installation about honeybees and communities that includes documentation of my first year as a beekeeper, sculpture, food, and interactive performance. This paper interweaves details about the exhibition with facts about honeybee biology, behavior, and folklore and reflections about my personal background with anti-hierarchical feminist organizing and collaboration.
2
Wu, Judy Yu. "Sub-lethal effects of pesticide residues in brood comb on worker honey bees (Apis mellifera L.)." Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Thesis/Spring2010/j_wu_042110.pdf.
Testo completo
3
Ellis, Michael B. "Homeostasis : humidity and water relations in honeybee colonies (Apis mellifera)." Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-10022009-135223/.
Testo completo
4
Hanekom, Marc C. "The effect of brood and queen pheromones, as well as the colony environment, in the success of Apis mellifera capensis social parasites." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/426.
Testo completo
5
Alhamlan, Fatimah S. "Evidence for genetic differences in the Africanized honey bee populations of South and North America." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Summer2007/f_alhamlan_052207.pdf.
Testo completo
6
Smart, Matthew Dixon. "Distribution of microsporidia, Nosema spp., and co-infection with acarine parasites in Pacific Northwest honey bee (Apis mellifera L.) colonies." Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Thesis/Spring2010/m_smart_060310.pdf.
Testo completo
7
Jones, Georgina Elizabeth. "The mandibular gland secretions of the Cape honeybee (Apis mellifera capensis ESCH.) : factors affecting the production of the chemical signal and implications for further development of beekeeping in South Africa." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1005416.
Testo completoAbstract (sommario):
The chemical composition of the mandibular gland extracts of Apis mellifera capensis virgin queens was analysed by gas chromatography-mass spectroscopy. Thirty-seven compounds from various chemical groups including aliphatic and aromatic acids and diacids, phenols, alkanes, amino acids and sugars were identified. Among the identified compounds were the queen mandibular pheromone components 9ODA, 9HDA, HVA and HOB and the other aliphatic acids and phenols considered to be the major components of A.m. capensis mandibular glands. Ontogenetic changes in the concentration of the mandibular gland secretions of virgin queens were largely quantitative in nature with the total volume and that of most of the compounds increasing with queen age. The final level of 9ODA is reached at the premating stage, approximately three days after emergence, when it comprises approximately 87% of the major constituents of the mandibular gland signal. Hostile reactions by workers towards introduced virgin queens can be correlated to the relative proportion of 9ODA present in the mandibular gland secretions. This seems to indicate that it is the complete spectrum of the signal and not individual compounds that determine worker reaction towards introduced queens. Keeping queens singly, with or without workers, in an incubator and in small mating nucleus hives proved to be the most successful methods of queen rearing in respect to survival rate in A.m. capensis. The presence of workers during the ageing of virgin queens was found to significantly affect the chemical composition of the mandibular gland secretions of queens. The reaction of workers towards introduced virgin queens reared under different holding conditions varied, with queens reared with workers eliciting significantly less hostile reactions from workers than those reared without workers. Mated queens from five localities in the Eastern Cape were characterised on the basis of the chemical composition of their mandibular gland secretions and the ratio of 9ODA:10HDA. No significant differences were detected and none of the queens sampled could be considered to be A.m. capensis based on their mandibular gland signal. The findings of this study provide baseline data for the development of a queen-rearing program tailored to the specific requirements of A.m. capensis.
8
Muerrle, Thomas Martin. "Queens, pseudoqueens and laying workers reproductive competition in the Cape Honeybee (Apis mellifera capensis Eschscholtz)." Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1005437.
Testo completoAbstract (sommario):
In honeybees (Apis mellifera L.) the queen monopolises reproduction. However, especially after queen loss, workers can lay eggs, but are unable to mate. They produce haploid male offspring (drones) from unfertilised eggs via arrhenotokous parthenogenesis. In contrast, workers of the honeybee subspecies Apis mellifera capensis Eschscholtz typically produce diploid female offspring from unfertilised eggs thelytokously. After queen loss and without queen-derived brood A. m. capensis colonies can successfully requeen from worker-derived brood. This, however, is a relatively rare event in wild populations. Moreover, workerderived queens were described to be smaller, more worker-like and reproductively inferior. On the other hand, the fixation of the thelytokous trait relies mainly on sufficient numbers of viable drones produced by worker-derived queens. Small numbers of reproductively inferior worker-derived queens in A. m. capensis populations would be clearly counterintuitive. It is therefore necessary to quantify the significance of worker-dependant queen rearing pathways on the individual (queen) and on population level.Reproductive inferiority of worker-derived queens could not be confirmed on the individual (queen) level when comparing parameters indicating potential reproductive success of queen- and worker-derived queens. Queen- and worker-derived queens clearly showed a congruent range of reproductive performance. In queen rearing preference tests, increased acceptance of worker-derived female larvae was exactly counterbalanced by increased mortality, resulting in an equal number of eclosing virgin queens from an equal number of grafts in both test groups. Larval survival and successful eclosion is a prerequisite for a queen’s reproductive success. I found no difference in eclosion success for queen- and worker-derived virgin queens, indicating a similar potential for reproductive success in both queen types. Assessments of the developmental patterns of colonies headed by both queen and worker-derived queens in long-term experiments revealed no significant differences in reproductive success. Colonies headed by queen-derived queens and colonies headed by worker-derived queens could not be separated when comparing the different developmental pathways observed or from differences in worker-force. Reproductive dominance in A. m. capensis appeared tobe determined by a function of relative compositional and absolute quantitative pheromonal patterns, where individuals, which produce compositionally most queen-like blends in highest quantities, occupy top positions. Queen- and worker-derived virgin queens occupied intermediate positions between pseudoqueens and mated queens. However, no significant differences between the pheromonal status of queen- and worker-derived virgin queens were observed, suggesting a similar range of reproductive dominance for both queen types. In behavioural bioassays queen- and worker-derived virgin queens appeared to be similarly attractive to clustering workers and to drones in a drone congregation area, indicating no differences in potential reproductive success for queens from both origins for those parameters. The significant influence of the queen substance 9-ODA on attractiveness to workers and drones was confirmed. Rare requeening events from worker-derived female brood in queenless A.m. capensis do not satisfactorily explain the fixation of the thelytokous trait at a population level. I observed A. m. capensis worker ovipositing into empty artificial queen cell cups in queen-right colonies. The queen was confined behind a queen excluder grid in a separate compartment of the colony, to imitate reduced pheromonal flow, similar to swarming or superseding colonies. Eggs oviposited by workers in artificial queen cell cups were readily accepted for queen rearing and successful eclosion of viable virgin queens was observed. Consequently I suggested an alternative worker-dependant reproductive pathway in A. m. capensis, which was never described before: In swarming or superseding queenright colonies, laying workers may directly compete with the queen for reproductive success by ovipositing (instead of the queen) into natural queen cell cups. At a population level this reproductive tactic may result in large numbers of worker-derived queens of high reproductive quality in natural populations of A. m. capensis.
9
Mohammed, Nuru Adgaba. "Geographical races of the honeybees (Apis Mellifera L.) of the Northern regions of Ethiopia." Thesis, Rhodes University, 2003. http://hdl.handle.net/10962/d1007671.
Testo completoAbstract (sommario):
The ideal climatic conditions and diversity of floral resources allow Ethiopia to sustain millions of honeybee colonies. Beekeeping is widely practiced and plays a significant role in the livelihood of the farming community of the country. Despite this, information on the types of geographical races of honeybees, their behavioural characters and the related ecological factors are not established. In this work an attempt was made to characterise the honeybee populations of the northern parts of Ethiopia based on the analyses of morphological, behavioural and ecological characteristics. For morphological analysis, 155 honeybee colony samples from 31 localities were collected. 20 worker honeybees per colony sample totalled 3100 individual worker honeybees and thirteen morphological characters per bee, a total of 40 300 measurements were recorded following Ruttner's (1988) protocols. The behavioural characters such as reproductive swarming, migration, temperament and colony seasonal cycles were assessed based on survey work of a pre-structured questionnaire. Various univariate and multivariate statistical methods were employed to analyse the data. The principal components and step-wise linear discriminant analyses revealed the existence of four discrete morphoclusters or geographical races: A. m. jemenitica from eastern, northwestern and northern arid and semi-arid lowlands, A. m. scutellata from the western humid midlands, A. m. bandasii from sub-moist central highlands and A. m. monticola from the northern mountainous parts of the study areas. These different geographical races were found to be distinctively distributed in the different ecological parts of the study area. High intercolonial and intracolonial variances were observed in all localities, however particularly high values were obtained in areas of transitions between ecological zones indicating a region of gene flow or zones of hybridisation among the statistically defined populations. Such high variances were observed mostly in areas where A. m. jemenitica borders the other geographical races. Moreover. distinct behavioural variations were also noted among these geographical races. Generally. the highland and mountainous honeybees A. m. bandasii and A. m. monticola are relatively larger in body size. have less tendency to swarm. less inclination to migrate and are relatively gentle while the converse traits were noted for the lowlands and midlands honeybees A. m. jemenitica and A. m. scutellata. Both morphological and behavioural variations were highly correlated with environmental factors and the variations seem to be the result of long adaptation to the interrelated ecological factors in their respective areas. Variations in reproductive swarming periods were also noted among these honeybee populations as a result of variations in rainfall pattern. altitude and temperature in their respective ecological areas which are believed to alter the honeybee colonies' seasonal cycles and leads to partial temporal reproductive isolation among these different honeybee populations.
10
Pirk, Christian Walter Werner. "Reproductive conflicts in honeybee colonies." Thesis, Rhodes University, 2002. http://hdl.handle.net/10962/d1005443.
Testo completoAbstract (sommario):
In advanced eusocial hymenopteran societies workers have ovaries and can lay eggs, but are unable to mate. Workers are more related to their own offspring than to every other member of the colony. So worker reproduction contains both worker-worker and worker-queen conflict. The queen- worker conflict is discussed elsewhere, but if the queen mates with more than two males, worker policing should be selected to lower potential conflicts. However in the Cape honeybee it was predicted that worker policing is absent or less expressed than in other honeybee subspecies, because workers produce female offspring thelytokously. So laying workers and their offspring are nearly genetically identical, which results in the fact that other workers are as related to workers derived from eggs laid by the queen as laid by a worker. However, worker reproduction may be costly and therefore worker policing could be an evolutionary adaptation in the Cape honeybee to lower the costs derived from laying worker activity. Indeed, Cape honeybee colonies show efficient egg removal behaviour, suggesting that other factors like colony efficiency could favour egg removal behaviour. Since egg removal behaviour is a colony phenomenon, factors that affect colony performance could also affect egg removal behaviour. Egg removal behaviour was considerably affected by environmental changes, indicating that other tasks have a higher priority than egg removal behaviour. Thousands of queenright colonies of the neighbouring subspecies (A. m. scutellata) were taken over by laying A. m. capensis workers, showing that A. m. capensis workers are facultative social parasites. These observations strongly indicate that laying workers of A. m. capensis are able to evade worker policing and the inhibitory effects of the queen pheromones, but what potential strategies could these laying workers use to increase the survival of their eggs and evade the queen? On the one hand, egg removal behaviour is variable. One behavioural strategy of laying workers to achieve successful reproduction could be that they lay during periods with low egg removal behaviour. On the other hand, the inhibitory effect of the queen’s pheromones diminishes with distance. Maybe the level of egg removal also depends, like the inhibitory effect of the queen pheromones, on the distance from the queen. Indeed, further away from the queen the effect of the queen pheromone and the level of egg removal is reduced, making successful worker reproduction possible. In both subspecies, A. m. capensis and A. m. scutellata, egg removal behaviour is reduced further away from the queen. In the case of A. m. scutellata egg removal is lacking further away from the queen. This explains why colonies of scutellata are so prone to takeovers by laying Cape honeybee workers. One question in the context of parasitic Cape honeybees is how they manage to get into the host colony. One way could be that they get into the colonies during a natural colony merger which is common in African bees. Two unrelated colonies merged and it took them only 24 hours to show effective integration. Because both colonies are unrelated, the potential reproductive conflict among workers should be more strongly expressed than in a normal colony, which is not the result of a merger. Therefore, the effect of nestmate recognition for eggs on the egg removal behaviour was investigated. The results suggest that workers recognise the origin of an egg and that the standard policing experiments overestimate the level of egg removal and only represent relative values. Moreover, the results show that colony specific components on the eggs are more important than a postulated queen egg marking pheromone. Finally, for the first time empirical evidence from a population of the parasitic laying Cape honeybee workers, invading thousands of colonies of A. m. scutellata in northern South Africa, for a short-sighted selection theory is presented.
11
Tetzlaff, Michael James. "Bee-ing there the systematicity of honeybee navigation supports a classical theory of honeybee cognition /." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3507.
Testo completoAbstract (sommario):
Thesis (Ph. D.) -- University of Maryland, College Park, 2006.<br>Thesis research directed by: Philosophy. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
12
Reece, Sacha Louise. "The mandibular gland secretions and ovarial development of worker honeybees (Apis Mellifera) in the Eastern Cape Province of South Africa." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1005415.
Testo completoAbstract (sommario):
The Eastern Cape is an area in which Apis mellifera capensis, A. m. scutellata and their hybrid are known to naturally occur. I investigated the mandibular gland profiles and ovarial development of queenright workers from 4 localities. Their queens were then removed to determine how these aspects changed upon queen loss. In addition, drifted bees were analysed in the same way to determine how these factors changed once they had gained entry to a foreign hive. The queenright bees, form all 4 localities were found to have 9HDA as the most abundant of the 5 fatty acids measured and all localities had small percentages of 9ODA in their mandibular gland secretions. This resulted in relatively high queenright 9ODA:10HDA and 9HDA:10HDAA ratios. Despite this the percentage of bees with undeveloped ovaries was consistent with their queenright status. The mean values of these 2 ratios were significantly higher in the bees from East London and Cradock than those from Port Elizabeth. Steynsburg's bees were intermediate in this regard. Upon queen loss, the bees from all 4 localities had an increase in the percentage of 9ODA but the other compound changes in varying ways. East London's bees were the only ones not to become significantly more queen-like after queen loss. After 14 days without a queen, the mean values of these 2 ratios were much higher in the bees from Port Elizabeth than those from the other localities. Certain individuals from Port Elizabeth had values of these ratios that exceeded those found in A. m. capensis queens. Port Elizabeth was the only locality to display any surrogate queens and exhibited the highest increase in the number of bees with partially or fully developed ovaries. While certain individuals from the other localities had values of these ratios that exceeded these values reported in A. m. scutellata queens, Steynsburg's bees were the only ones that did increase in in terms of the number of bees with developed ovaries subsequent. The bees from Steynsburg were shown to suppress the mandibular gland and ovarial development of drifters from Port Elizabeth while bees from East London did not.
13
Du, Manuel. "Stochastic simulation studies for honeybee breeding." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22295.
Testo completoAbstract (sommario):
Die Arbeit beschreibt ein stochastisches Simulationsprogramm zur Modellierung von Honigbienenpopulationen unter Zuchtbedingungen. Dieses Programm wurde neu implementiert um unterschiedliche Selektionsstrategien zu evaluieren und zu optimieren. In einer ersten Studie wurde untersucht, inwiefern die Vorhersagen, die das Programm trifft, vom verwendeten genetischen Modell abhängt. Hierbei wurde festgestellt, dass das Finite-Locus-Modell dem Infinitesimalmodell in Langzeitstudien vorzuziehen ist. Eine zweite Studie beleuchtete die Bedeutung der sicheren Anpaarung auf Belegstellen für die Honigbienenzucht. Hier zeigten die Simulationen, dass die Zucht mit Anpaarungskontrolle derjenigen mit freier Paarung von Königinnen deutlich überlegen ist. Schließlich wurde in einer finalen Studie der Frage nachgegangen, wie erfolgreiche Zuchtprogramme bei der Honigbiene langfristig nachhaltig zu gestalten sind. Hierbei sind kurzfristiger genetischer Zugewinn und langfristige Inzuchtvermeidung gegeneinander abzuwägen. Durch umfangreiche Simulationen konnten für verschiedene Ausgangspopulationen Empfehlungen für eine optimale Zuchtintensität auf mütterlicher und väterlicher Seite gefunden werden.<br>The present work describes a stochastic simulation program for modelling honeybee populations under breeding conditions. The program was newly implemented to investigate and optimize different selection strategies. A first study evaluated in how far the program's predictions depend on the underlying genetic model. It was found that the finite locus model rather than the infinitesimal model should be used for long-term investigations. A second study shed light into the importance of controlled mating for honeybee breeding. It was found that breeding schemes with controlled mating are far superior to free-mating alternatives. Ultimately, a final study examined how successful breeding strategies can be designed so that they are sustainable in the long term. For this, short-term genetic progress has to be weighed against the avoidance of inbreeding in the long run. By extensive simulations, optimal selection intensities on the maternal and paternal paths could be determined for different sets of population parameters.
14
Amssalu, Argaw Bezabeh. "Multivariate morphometric analysis and behaviour of honeybees (Apis Mellifera L.) in the southern regions of Ethiopia." Thesis, Rhodes University, 2003. http://hdl.handle.net/10962/d1003130.
Testo completoAbstract (sommario):
Morphometric and behavioural characteristics of honeybees, Apis mellifera were analysed using multivariate and bivariate statistical methods to characterise honeybees of southern Ethiopian region. A total of 33800 morphometric character measurements were taken from 2600 individual worker honeybees of 130 honeybee colonies collected at 26 sampling localities with an average inter-locality distance of 89km to determine the occurrence of morphoclusters. 117 experienced farmer beekeepers and beekeeping experts were interviewed on pre-tested questionnaire to investigate the behavioural characteristics of these honeybees in their respective areas. Morphometric characters associated with pigmentation and body size exhibited a higher discriminant power while forewing venation angles (B4, N23 and 026) lack discriminatory power to segregate honeybees in the southern Ethiopian region. Principal components and discriminant analyses using the most discriminatory morphological characters delineated four statistically distinct morphoclusters in the southern Ethiopian region: the smallest and yellow honeybees, A. m. woyi-gambella which are different from all African honeybees, occur in the western and southern lowlands; the small and yellowiest honeybees, Apis mellifera jemenitica in the eastern escarpment; the largest and darkest honeybees, Apis mellifera bandasii in the central and eastern highlands; and dark honeybees, Apis mellifera scutellata in the wet tropical forests. High intracolonial and intercolonial variances within and between the boundaries of the honeybee groups were detected. The former suggests areas of ecological instability, while the latter areas of transitional or natural hybridisation zones. These areas are characterised by transitional ecological zones having intermediate climate and physiography. Even though honeybees of the southern Ethiopian region are generally dark and small, they show a high tendency to reproductive swarming, migration and aggressiveness, great variation in pigmentation, size and behaviour were observed both within and between the groups. A. m. jemenitica honeybees have a high propensity to migration and less a tendency for reproductive swarming. A. m. bandasii and A. m. scutellata have a high inclination to reproductive swarming and the former has a lesser and the later intermediate propensity to migration. A. m. woyi-gambella honeybees have intermediate swarming and migration tendencies. These results revealed that reproductive swarming and migration are higher in resource-rich and resource-poor areas respectively. Honey plants of the central highlands of Ethiopia are predominantly herbaceous in nature and mainly grow on open and cultivated lands. The bulk of pollen collected came comparatively from few genera. Strong correlation was observed between the intensities of flowering and rainfall. Reproductive swarming and migration occur during high and low intensity of flowering respectively.
15
Jimenez, Desmond Rito. "Ultrastructure and function of the ventriculus of the honey bee, Apis mellifera." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184266.
Testo completoAbstract (sommario):
The ventricular epithelia of adult worker honey bees were investigated biochemically and ultrastructurally. The midgut tissues were shown to produce an endoprotease with trypsin-like activity. Enzyme activity was highest in the midgut tissues and the ectoperitrophic space of free-flying honey bees and of caged bees fed pollen. Lower levels of activity occurred in caged bees restricted to sucrose or fed artificial diets. The trypsin-like activity declined as the protein intake of the bees decreased with age. Ultrastructural studies revealed columnar cells in the posterior midgut engaged in the synthesis and release of membrane-bound vesicles. The apical cytoplasm of the epithelial cells in this region contains numerous electron dense vesicles which are released into the ectoperitrophic space of the midgut lumen. The microvilli in the crypts of this region are short, branching, and microvesiculate. Throughout the remainder of the midgut, the microvilli are profuse and elongate. The presence of the endogenously produced endoprotease and the regional variation in cell ultrastructure suggest that the honey bee may rely on countercurrent flow to distribute enzymes and nutrients efficiently throughout the midgut. Ultrastructural cytochemistry localized acid phosphatase and nonspecific esterase activity in primary and secondary lysosomes dispersed throughout the midgut tissues. Alkaline phosphatase activity was localized within large electron lucent microbodies that are present in all midgut columnar cells. The peroxisomal marker enzymes, catalase and L-α-hydroxy acid oxidase, were also localized in the same microbodies which previously had been described as holocrine secretory granules involved in dietary mineral regulation. Morphological and cytochemical assays suggest that the holocrine secretory granule arises from a microperoxisomal compartment involved in intermediary metabolism in the midgut of adult honey bees.
16
Ellis, Michael Battiscombe. "Homeostasis : humidity and water relations in honeybee colonies (Apis mellifera)." Diss., University of Pretoria, 2008. http://hdl.handle.net/2263/28357.
Testo completoAbstract (sommario):
One of the benefits of colonial living in insect societies is the ability to build a nest which enables the maintenance of a homeostatic microenvironment. The detrimental and uncertain effects of fluctuating ambient conditions are thus avoided. An extensive amount of work has documented the regulation of respiratory gases and temperature by honeybee (Apis mellifera) colonies but relatively little is known of their water relations. Nest humidity influences the fitness of the honeybee colony by affecting adult and brood mortality, microbial and parasitic growth, nectar concentration and thermoregulation. This study aims at determining whether honeybee colonies are able to actively regulate humidity within their nest or whether humidity is stabilised merely as consequence of other socially regulated parameters. As a first step in understanding water relations in a hive, the daily, seasonal and two-dimensional humidity patterns are described in diverse contexts: various subspecies, nest architectures, ambient climates and colony conditions. The humidity in the brood nest of a healthy honeybee colony does not show a daily pattern: mean hourly RH remains between 50 and 60 % and high vapour pressure deficit results in a large evaporative capacity. Two-dimensional humidity patterns show that a vapour pressure gradient exists from the central brood area to the periphery of a hive. This finding suggests possible active regulation by workers and to test this idea we determined the behavioural response of a group of workers to a humidity gradient. Young honeybee workers in the absence of brood exhibit a weak hygropreference for approximately 75% RH. When brood is present the expression of this preference is further weakened, suggesting that workers tend to the brood by distributing evenly in the gradient. In addition, fanning behaviour is shown to be triggered by increasing humidity adding to our understanding of this behaviour. Although these results suggest that humidity in honeybee colonies is actively controlled by workers, passive mechanisms are also involved in the observed patterns. Cocoons that are spun by the larvae accumulate in cells and these hygroscopic cocoons contribute to passive stabilisation of humidity. Old comb containing cocoons absorb 11 % of its own mass in water when placed in high humidity and this water can readily evaporate into the atmosphere when humidity decreases. This buffering effect may increase brood survivorship by maintaining a high and stable humidity in the brood cells. This study contributes to our understanding of the complex mechanisms that govern microclimatic regulation in social insect nests and specifically the active and passive mechanisms that ensure homeostasis of honeybee nest humidity. Copyright<br>Dissertation (MSc)--University of Pretoria, 2009.<br>Zoology and Entomology<br>unrestricted
17
Wharton, Katie Elizabeth. "Queen and worker influence on sex allocation patterns in the honeybee, Apis mellifera." Diss., Connect to online resource - MSU authorized users, 2008.
Cerca il testo completoAbstract (sommario):
Thesis (Ph. D.)--Michigan State University. Dept. of Zoology, Program in Ecology, Evolutionary Biology, and Behavior, 2008.<br>Title from PDF t.p. (viewed Aug. 19, 2009). Includes bibliographical references (p. 88-95). Also issued in print.
18
Litchwark, Simon. "Honeybee declines in a changing landscape: interactive effects of honeybee declines and land-use intensification on pollinator communities." Thesis, University of Canterbury. School of Biological Sciences, 2013. http://hdl.handle.net/10092/9064.
Testo completoAbstract (sommario):
Honeybees are used as a major agricultural input around the world and their pollination services have been valued at US$14.6 billion to the United States alone. Dramatic declines in honeybee populations around the globe, however, questioned the sustainability of this reliance on a single pollinator species. In this study, I investigated the response of wild pollinator communities to declining honeybee density and changing land use intensity to determine the potential of wild pollinators to compensate for honeybee loss in an increasingly human-modified environment. I generated a gradient of declining honeybee density using increasing distances from commercial bee hives, and conducted flower observations on experimentally-grown plants across this gradient. I investigate how declining honeybee densities and intensifying land use combine to influence the composition of the pollinator community as a whole, then go on to explore individual trends in the most common pollinator species. I then analyze how this impacts the transport of viable pollen by the pollinator community and determine how these changes alter seed set in several common plant species. I then change my focus away from the composition of the pollinator community, and instead investigate how declining honeybee densities and land-use intensification influence the structuring of interactions between plants and pollinators within the community. I identify the pollen species carried by pollinators, and use this to construct a network of pollination interactions. I then use this network to analyze how changes in the way species interact influences the pollination services delivered by the pollinator community to different plant groups (weeds, native plants, and crop species).
My findings show that honeybee declines may have a large impact on community structure and interactions within pollination systems. I observed a significant shift in the wild pollinator community composition as honeybee densities declined, from a generally bee/hoverfly dominated community to one more dominated by large flies. This was associated with a significant decline in the total pollen load transported by the community, indicating that pollination services may suffer in the absence of honeybees. As honeybee densities declined, however, I also observed a shift toward greater specialisation of pollinators on abundant resources, increased pollinator constancy, and a higher viability rate of the pollen transported. These findings show that although the total amount of pollen transported by the community declined as honeybee densities decreased, the probability of this pollen transport resulting in effective pollination likely increased. Thus, I observed no decrease in seed set with honeybee declines in any of the three plant species tested, and one of these even showed a significant increase. Finally, I also demonstrated that this change differentially affected different plant types, and that the extent of changes to each plant species differed between land-use types. This reflected changes in the relative abundance of pollen types in different land uses, with greater specialisation in the absence of honeybees disproportionately benefiting common species. These findings have strong implications for several contemporary issues in pollination biology, both locally within New Zealand and on a global scale. These are discussed in the following sections.
Finally, I conclude by discussing the implications of this research on several contemporary issues in pollination biology, namely the ability for wild pollinators to compensate for honeybee declines, the impact of honeybees on natural new Zealand ecosystems, the contribution of honeybees to invasive weed pollination and finally the management of surrounding land use types to maximize the effectiveness of wild pollinators.
19
Delaney, Deborah A. "Genetic characterization of U.S. honey bee populations." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Dissertations/Summer2008/d_delaney_070108.pdf.
Testo completo
20
Sachse, Silke. "Odor processing in the honeybee antennal lobe." [S.l. : s.n.], 2002. http://www.diss.fu-berlin.de/2002/196/index.html.
Testo completo
21
Scheiner, Ricarda, Arnd Baumann, and Wolfgang Blenau. "Aminergic control and modulation of honeybee behaviour." Universität Potsdam, 2006. http://opus.kobv.de/ubp/texte_eingeschraenkt_verlag/2010/4610/.
Testo completoAbstract (sommario):
Biogenic amines are important messenger substances in the central nervous system and in peripheral organs of vertebrates and of invertebrates. The honeybee, Apis mellifera, is excellently suited to uncover the functions of biogenic amines in behaviour, because it has an extensive behavioural repertoire, with a number of biogenic amine receptors characterised in this insect. In the honeybee, the biogenic amines dopamine, octopamine, serotonin and tyramine modulate neuronal functions in various ways. Dopamine and serotonin are present in high concentrations in the bee brain, whereas octopamine and tyramine are less abundant. Octopamine is a key molecule for the control of honeybee behaviour. It generally has an arousing effect and leads to higher sensitivity for sensory inputs, better learning performance and increased foraging behaviour. Tyramine has been suggested to act antagonistically to octopamine, but only few experimental data are available for this amine. Dopamine and serotonin often have antagonistic or inhibitory effects as compared to octopamine. Biogenic amines bind to membrane receptors that primarily belong to the large gene-family of GTP-binding (G) protein coupled receptors. Receptor activation leads to transient changes in concentrations of intracellular second messengers such as cAMP, IP3 and/or Ca2+. Although several biogenic amine receptors from the honeybee have been cloned and characterised more recently, many genes still remain to be identified. The availability of the completely sequenced genome of Apis mellifera will contribute substantially to closing this gap. In this review, we will discuss the present knowledge on how biogenic amines and their receptor-mediated cellular responses modulate different behaviours of honeybees including learning processes and division of labour.
22
Põlajev, Aleksei. "Selfish, mobile genes in honeybee gut bacteria." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-360510.
Testo completoAbstract (sommario):
Transposons are selfish, mobile genetic elements, moving within the genome. The transposase genemakes this possible, as it codes for the enzyme that catalyzes the movement. In the case of bacteria,they can also move horizontally between individual bacteria, and sometimes even between species.By default, they are a burden for the host organism, coding for a protein that the host does not need.They also pose the risk of disabling the host’s crucial genes by inserting themselves into it.Transposons are under some pressure to benefit the host, to help propagate themselves moreeffectively. And some transposons have indeed evolved to benefit the host. Lactobacillus kunkeei is a bacterial species known to reside in honeybee guts. It is known for itsrole in honey preservation and wine spoilage. The genome of L. kunkeei is reduced because it is asymbiont, however it contains an unusually high amount of transposons in its genome. In this study, the transposase genes (transposon enzymes) found in L. kunkeei are studied andcategorized. The L. kunkeei have been extracted from honeybees (Apis mellifera). The honeybeesthemselves have been collected from the islands Åland and Gotland. This study focuses on the transposase genes that come in pairs, one after another in the genome.Transposase genes were identified using annotation software and orthology-based methods. Theannotation software provides numbering for the genes, which allows finding paired genes. Thepaired genes were categorized based on alignments and phylogenetic software. Pseudogenizedtransposons were identified based on length and/or clustering into triplets. A total of 766 paired transposase genes were found. The transposase genes were found to take up1.9% of the genome, on average. A low level of diversity has been found when performingalignments and generating phylogenetic trees. The positions of the transposase genes are generallyconserved within phylogenetic groups. Pseudogenization has been detected for some transposasegenes – 4.5 per genome, on average. All of the studied transposons belong to the IS3 family, whichis a family of Class I transposons.
23
Miller, Jeremy J. "You My Honeybee, I'm Your Funky Butt." Miami University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=miami1154716100.
Testo completo
24
Swart, Dawid Johannes. "The occurrence of Nosema apis (Zander), Acarapis woodi (Rennie), and the Cape problem bee in the summer rainfall region of South Africa." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1015980.
Testo completoAbstract (sommario):
The occurrence of Nosema disease, tracheal mites and the “pseudo-parasitic” behaviour of Cape honeybee workers when placed amongst African honeybees – known as the Cape Bee Problem – were studied over a 18 month period. Three surveys, approximately 6 months apart were done. The aims of this study were to establish the distribution and severity of the diseases and compare the disease with the presence of the Cape Bee Problem. Before this survey commenced European Foul Brood disease, Sacbrood (virus), Nosema, Brood nosema, and Tracheal mite have sporadically been reported in the summer rainfall region of South Africa. In the first survey 1005 colonies in 61 apiaries were surveyed, 803 colonies in 57 apiaries in the second, and 458 colonies in 41 apiaries in the third. Samples for disease and parasite analysis were taken at 4 colonies per apiary. Ten colonies per apiary were inspected for Cape Problem Bees, and samples of workers were collected and dissected at each of these colonies. Even with the addition of apiaries to 'fill-up' lost colonies during the second survey, 63% of all colonies were lost by the third survey. There was only a small difference in colony loss between sedentary and migratory beekeepers of 22% compared to 27%. Nosema was more prevalent amongst commercial beekeepers and increased in migratory operations during the survey period. The percentage of colonies infected increased during the survey period from 23% to 32% to 34%. The placement of colonies in Eucalyptus plantations may boost infection. Trachea mites seem to have spread quite rapidly in South Africa since its discovery. This parasitic mite was present in all regions, although in low numbers in three most northern regions. Sedentary colonies had higher levels of infestation than migratory colonies. The number of colonies infested diminished over the survey period, which may be a result of general colony loss. The Cape Problem Bee was less of a problem than anticipated. Colonies succumbed to Cape Problem Bees in all regions. When beekeepers reported high levels of infestation in their bee stocks the colonies would be dead within six months. In apiaries with low infestation the die-out was slower.
25
Radloff, S. E. (Sarah E. ). 1948. "Multivariate analysis of selected honeybee populations in Africa." Thesis, Rhodes University, 1996. http://hdl.handle.net/10962/d1005420.
Testo completoAbstract (sommario):
Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus were analysed by multivariate methods to characterise selected honeybee populations along five transects in Africa at a meso-scale level of sampling distance resolution. In some, but not all, areas pheromonal clusters were found to be coincident and concordant with the morphometric clusters, thus indicating that different honeybee traits have dispersed variably among populations. All transects were found to contain areas of significantly high variance. High intracolonial variance was taken to indicate localised genetic variation coupled with out-cross matings. Centroids of high intercolonial variance occured at and between cluster boundaries and were typical of transitions between, and rainfall-temperature discontinuities within, ecological-climatological zones, hence areas of ecological instability. Principal component and stepwise discriminant analysis yielded three morphometric clusters corresponding to A. m. sahariensis and A. m. intermissa in Morocco and to A. m. iberica (with three biometric populations) in Spain, but no pheromone clusters. The combined morphometric and pheromonal variance spectra indicated regions of natural hybridisation along a Sahara-Pyrenees transect. In the Horn of Africa, discrete and statistically homogeneous populations were identified: A. m. jemenitica, A. m. bandasii, A. m. sudanensis in Ethiopia and an unclassified group in southwestern Somalia. Areas of high intercolonial variance were interpreted as zones of hybridisation between the populations. Along a transect in west central Africa, three distinct homogeneous populations and two zones of hybridisation were found. These bees were designated as A. m. adansonii whose area of distribution was intruded by an un-named mountain group of bees and a third group, A. m. jemenitica. The delineation of the hybrid zones was supported by intercolonial variance spectra and these significant asymmetries were found to be coincident with transitions between the ecological-climatological zones. In southwestern Africa, two discrete homogeneous populations and a zone of hybridisation between them were identified: A. m. scutellata in northern South Africa and southern Namibia and A. m. adansonii in northern Namibia. Along a transect in the southeastern woodland savanna of Africa, three discrete populations were classified: A. m. litorea in Mozambique, A. m. scutellata in Zimbabwe and A. m. adansonii in northwestern Zambia. A zone of introgression between the last two subspecies occured in south-central Zambia and in the Zambezi valley.
26
Du, Manuel [Verfasser]. "Stochastic simulation studies for honeybee breeding / Manuel Du." Berlin : Humboldt-Universität zu Berlin, 2021. http://d-nb.info/1226153194/34.
Testo completo
27
Roper, Mark. "Honeybee visual cognition : a miniature brain's simple solutions to complex problems." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/25938.
Testo completoAbstract (sommario):
In recent decades we have seen a string of remarkable discoveries detailing the impressive cognitive abilities of bees (social learning, concept learning and even counting). But should these discoveries be regarded as spectacular because bees manage to achieve human-like computations of visual image analysis and reasoning? Here I offer a radically different explanation. Using theoretical bee brain models and detailed flight analysis of bees undergoing behavioural experiments I counter the widespread view that complex visual recognition and classification requires animals to not only store representations of images, but also perform advanced computations on them. Using a bottom-up approach I created theoretical models inspired by the known anatomical structures and neuronal responses within the bee brain and assessed how much neural complexity is required to accomplish behaviourally relevant tasks. Model simulations of just eight large-field orientation-sensitive neurons from the optic ganglia and a single layer of simple neuronal connectivity within the mushroom bodies (learning centres) generated performances remarkably similar to the empirical result of real bees during both discrimination and generalisation orientation pattern experiments. My models also hypothesised that complex 'above and below' conceptual learning, often used to exemplify how 'clever' bees are, could instead be accomplished by very simple inspection of the target patterns. Analysis of the bees' flight paths during training on this task found bees utilised an even simpler mechanism than anticipated, demonstrating how the insects use unique and elegant solutions to deal with complex visual challenges. The true impact of my research is therefore not merely showing a model that can solve a particular set of generalisation experiments, but in providing a fundamental shift in how we should perceive visual recognition problems. Across animals, equally simple neuronal architectures may well underlie the cognitive affordances that we currently assume to be required for more complex conceptual and discrimination tasks.
28
Allsopp, Mike. "Analysis of Varroa destructor infestation of southern African honeybee populations." Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-08082007-153050.
Testo completo
29
Hapke, Samuel David. "Integrated management of Varroa destructor Anderson & Trueman (Acari: Varroidae) in honey bees, Apis mellifera l. (Hymenoptera: Apidae), in western Washington State, USA." Pullman, Wash. : Washington State University, 2008. http://www.dissertations.wsu.edu/Thesis/Fall2008/s_hapke_111008.pdf.
Testo completo
30
Taylor, Kevin Stuart 1958. "Toxicity of synthetic pyrethroid insecticides to the honey bee (Apis mellifera L.)." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276577.
Testo completoAbstract (sommario):
Honey bees (Apis mellifera L.) were exposed to six pyrethroid insecticides using four application techniques. Toxicities of the insecticides were compared. Results of topical and contact tests placed the six pyrethroids in one of three categories based on their relative toxicity to honey bees; highly toxic (cyfluthrin, cypermethrin, and permethrin), moderately toxic (flucythrinate and fenvalerate), and non-toxic (fluvalinate). The residue tests, by contrast, simulated field conditions by using sprayed cotton leaves for exposure. This test showed that both compound and formulation played an important role in determining toxicity. The conditioning test combined some of the previously used techniques and refined them into a test for detecting behavioral changes to bees following sublethal exposure to pesticides. Insecticide-treated honey bees had a lower learning curve than their respective control group. This indicates that, although bees may survive poisoning from pesticides, certain physiological functions are affected.
31
Al, Ali Alkattea Raghdan. "Ontogenetic and individual patterns of volatiles in honeybee queens Apis mellifera and its significance for the acceptance of queens in honeybee colonies." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:100-opus-2916.
Testo completo
32
Yang, Ming-Xian. "Studies on mixed-species colonies of honeybees, Apis cerana and Apis mellifera." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1005467.
Testo completoAbstract (sommario):
The honeybees Apis cerana and Apis mellifera are derived from the same ancestral base about two million years ago. With speciation and evolution, they have acquired many advanced living skills in common, but have also evolved very different living strategies due to different distributions. This thesis is an intensive study of the biology of the mixed-species colonies of these species, the aims of which were to investigate their behavioural relationships and uncover the evolutionary conserved features of their behaviours subsequent to speciation. The results show that the two species can form a stable society to perform normal tasks. First, workers of both species in the mixed-colonies could form the typical retinue behaviour to hetero-species queens, thus indicating that queen pheromones could be spread to and by both species. Secondly, both species did not show significantly different ovarian activation under hetero-species queens, suggesting that the queen pheromones more likely play a role of "honest signal" rather than a "repression" substance in the honeybee colonies. Thirdly, both species could mutually decode each other‘s waggle dances, with unexpectedly low misunderstanding; revealing that the dance language in a dark environment is quite adaptive for cavity-nesting honeybees. Fourthly, workers of both species could cooperate with each other in comb construction, although the combs they built contain many irregular cells. Interestingly, A. cerana workers could be stimulated by A. mellifera workers to perform this task, thus confirming self-organization theory in the colony. Fifthly, A. mellifera workers behaved more "defectively" in thermoregulation, but perhaps because A. cerana workers are more sensitive to changes in hive temperature. Given these differences in strategy, A. mellifera workers‘ performance might in fact reduce conflicts. Lastly, when faced with threats of predatory wasps, both species engaged in aggressive defence. Although they did not learn from each other‘s responses, species-specific strategies were adopted by each of them so that the defence of the mixed-colonies is very effective. I conclude that the two species can adapt to each other‘s efforts and task allocation is reasonably organized allowing mixed-species colonies to reach stability. These results suggest that all of the social behaviours discussed here were highly conserved following speciation. This thesis could provide some clues for the study of honeybee evolution from open-nesting to the transition of cavity-nesting.
33
Basile, Rebecca. "Thermoregulation and Resource Management in the Honeybee (Apis mellifera)." kostenfrei, 2009. http://www.opus-bayern.de/uni-wuerzburg/volltexte/2009/3979/.
Testo completo
34
Bodur, Cagri. "Genetic Structure Analysis Of Honeybee Populations Based On Microsatellites." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606592/index.pdf.
Testo completoAbstract (sommario):
We analyzed the genetic structures of 11 honeybee (Apis mellifera) populations from
Tü<br>rkiye and one population from Cyprus using 9 microsatellite loci. Average gene
diversity levels were found to change between 0,542 and 0,681. Heterozygosity levels,
mean number of alleles per population, presence of diagnostic alleles and pairwise FST
values confirmed the mitochondrial DNA finding that Anatolian honeybees belong to north
Mediterranean (C) lineage. We detected a very high level of genetic divergence among
populations of Tü<br>rkiye and Cyprus based on pairwise FST levels (between 0,0 and 0,2). Out
of 66 population pairs 52 were found to be genetically different significantly. This level of
significant differentiation has not been reported yet in any other study conducted on
European and African honeybee populations. High allelic ranges, and high divergence
indicate that Anatolia is a genetic centre for C lineage honeybees.
We suggest that certain precautions should be taken to limit or forbid introduction and trade
of Italian and Carniolan honeybees to Tü<br>rkiye and Cyprus in order to preserve genetic
resources formed in these territories in thousands of years. Effectivity at previously isolated
regions in Artvin, Ardahan and Kirklareli was confirmed by the high genetic differentiation
in honeybees of these regions. Genetically differentiated Karaburun and Cyprus honeybees
v
and geographical positions of the regions make these zones first candidates as new isolation
areas.
35
Stollhoff, Nicola. "Retrieval induced consolidation processes in the honeybee, Apis mellifera." [S.l.] : [s.n.], 2005. http://www.diss.fu-berlin.de/2006/54/index.html.
Testo completo
36
Kurdi, Heba Abdullataif. "Personal mobile grids with a honeybee inspired resource scheduler." Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/4519.
Testo completoAbstract (sommario):
The overall aim of the thesis has been to introduce Personal Mobile Grids (PMGrids) as a novel paradigm in grid computing that scales grid infrastructures to mobile devices and extends grid entities to individual personal users. In this thesis, architectural designs as well as simulation models for PM-Grids are developed. The core of any grid system is its resource scheduler. However, virtually all current conventional grid schedulers do not address the non-clairvoyant scheduling problem, where job information is not available before the end of execution. Therefore, this thesis proposes a honeybee inspired resource scheduling heuristic for PM-Grids (HoPe) incorporating a radical approach to grid resource scheduling to tackle this problem. A detailed design and implementation of HoPe with a decentralised self-management and adaptive policy are initiated. Among the other main contributions are a comprehensive taxonomy of grid systems as well as a detailed analysis of the honeybee colony and its nectar acquisition process (NAP), from the resource scheduling perspective, which have not been presented in any previous work, to the best of our knowledge. PM-Grid designs and HoPe implementation were evaluated thoroughly through a strictly controlled empirical evaluation framework with a well-established heuristic in high throughput computing, the opportunistic scheduling heuristic (OSH), as a benchmark algorithm. Comparisons with optimal values and worst bounds are conducted to gain a clear insight into HoPe behaviour, in terms of stability, throughput, turnaround time and speedup, under different running conditions of number of jobs and grid scales. Experimental results demonstrate the superiority of HoPe performance where it has successfully maintained optimum stability and throughput in more than 95% of the experiments, with HoPe achieving three times better than the OSH under extremely heavy loads. Regarding the turnaround time and speedup, HoPe has effectively achieved less than 50% of the turnaround time incurred by the OSH, while doubling its speedup in more than 60% of the experiments. These results indicate the potential of both PM-Grids and HoPe in realising futuristic grid visions. Therefore considering the deployment of PM-Grids in real life scenarios and the utilisation of HoPe in other parallel processing and high throughput computing systems are recommended.
37
Choudhary, Amir Fujita. "Olfactory perceptual invariance in the honeybee : a psychophysical approach." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.512179.
Testo completo
38
Rodrigues, Marisa Clemente. "Genetic parameters for morphometric traits of africanized honeybee drones." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2443.
Testo completoAbstract (sommario):
Estudos sobre estimação de parâmetros genéticos em abelhas, com foco em abelhas africanizadas e na casta masculina da espécie, são escassos. O objetivo desse estudo foi estimar correlações genéticas para peso e características morfométricas de zangões à emergência e maturidade, para que em futuros programas de melhoramento essas características possam servir como critérios de seleção. Foram estimados parâmetros fenotípicos e genéticos para peso (W), comprimento total (TL), comprimento do abdômen (AL), largura do abdome (AW), comprimento da asa (WL) e largura da asa (WW) de zangões à emergência (E ) e maturidade (M) recorrendo a modelos de análise uni e bicaracter. Os parâmetros genéticos como variância genética, herdabilidade e correlações genéticas foram estimadas por meio do procedimento Bayesiano usando amostragem de Gibbs. Resultados: Foram medidos 1117 zangões à emergência e 336 novamente à maturidade. De acordo com a análise unicaracter, as herdabilidades foram 0.78, 0.52, 0.56, 0.93 e 0.92 para WE, WM, ALM, WLM e WWM, respectivamente. A correlação genética entre WE e as restantes características variou entre 0.55 e 0.83. Conclusões: As características W E, WM, TLM, ALM, WLM, WWM, quando consideradas individualmente, podem ser usadas como critério de seleção porque a variância genética aditiva para essas características foi responsável por mais de 50% da variação fenotípica total. O W E pode ser usado como critério de seleção se se ambicionar o melhoramento das restantes características à emergência. Os parâmetros genéticos obtidos para peso, comprimento total e comprimento do abdome à emergência indicam que há potencial de ganho genético para as características morfométricas à maturidade. Esses critérios podem embasar o estudo genético quantitativo das características morfométricas e reprodutivas à maturidade, que são de difícil mensuração.<br>Available information on Africanized honeybee breeding, especially regarding the male component of the species, is almost non-existent. The aim of this study was to estimate genetic correlations for weight and morphometric traits of drones at emergence and maturity, so that in future breeding programs these traits can act as selection criteria through their genetic value. Phenotypic and genetic parameters were estimated for weight and morphometric traits such as weight (W), total length (TL), abdomen length (AL), abdomen width (AW), wing length (WL) and wing width (WW) at drones’ emergence (E) and maturity (M). Single-trait and two-trait models were used and parameters such as genetic variance, heritability and genetic correlations were calculated using a Bayesian approach. Results: A total of 1117 drones were measured at emergence and 336 again at maturity. In single-trait models, heritabilities were 0.78, 0.52, 0.56, 0.93 and 0.92 for WE, WM, ALM, WL M and WWM, respectively. The genetic correlation between WE and the remaining traits ranged from 0.55 to 0.83. Conclusions: Traits such as W E, WM, TLM, ALM, WLM, WWM, when considered individually, can be used as selection criteria because genetic variance for these traits accounted for more than 50% of the total phenotypic variance. The WE combined with other traits assessed at drones' emergence can be used in breeding programs for the improvement of the aforementioned traits. Breeding selection for weight or total length at emergence promises considerable genetic progress for weight at maturity. The combination of genetic parameters for reproductive and morphometric traits in drones properly supported by breeding programs relying on artificial insemination, for an effective mating control, will likely help in clarifying this possibility.
39
Bellavance, Jesse Peter. "A GIS design for honeybee management prototype & assessment /." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=608.
Testo completoAbstract (sommario):
Thesis (M.A.)--West Virginia University, 1999.<br>Title from document title page. Document formatted into pages; contains v, 42 p. : ill. (some col.), maps Vita. Includes abstract. Includes bibliographical references (p. 38).
40
Rumkee, Jack Charles Oliver. "Modelling the impact of stressors on the honeybee colony." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/27654.
Testo completoAbstract (sommario):
The Western Honeybee (Apis mellifera) is an important species, not only ecologically and economically, but as a source of recreation to many. The pollination services the species provides benefit a number of crops worldwide, and, as the honeybee is domesticated and kept in hives, can be directed commercially. Recently, although overall global stocks are growing, there have been reports of high colony losses worldwide. Due to the value of this species, this is a worrying trend. There are many stressors facing the honeybee, both natural and anthropogenic in origin. Two of the most prevalent, both in the popular media and in monitoring studies of colonies are insecticidal pesticides and the parasitic mite Varroa destructor. Due to the difficulties and expense of carrying out large-scale field studies required to properly investigate the multiple stressors and their interaction, the use of modelling to explore the problem and direct field work is a vital resource. In this thesis, I present research using the BEEHAVE model and a novel model to explore the exposure and potential impacts of pesticides and the varroa mite. The results show that the timing of a pesticide exposure in the year greatly changes the resultant impact on the colony. Pesticides can have many impacts on different stages of the honeybee, and I show that increased mortalities of different life stages of the honeybee (larvae, in-hive adults, foragers) and decreasing egg-laying rate, affect the development of the colony to different extents at different times of the year, with the colony being highly sensitive to losses of in-hive bees during the summer, and the over-wintering bees at the beginning and end of the year. A novel model is presented exploring the in-hive distribution of pesticide-containing nectar and the effect it has on the exposure of in-hive receiving bees and larvae. The results from this model show that, in-hive distribution is not important to consider for the adults, but may be for the larvae. The landscape, specifically the distance to pesticide-treated forage in relation to untreated forage also has an impact on the result of a pesticide exposure, and this is a potential avenue for the mitigation of pesticide impacts. I also present work towards the validation of BEEHAVE with regards to varroa mite infestation, finding that the model results are close to empirical data, both for datasets from the UK and USA, but the impact of varroa is underestimated. The results are discussed in the context of pesticide risk assessment, the mitigation of potential stressors and the modelling of the varroa mite. The BEEHAVE model is a vital tool for many applications, one being the risk assessment of pesticides. A review of the model by the European Food Security Agency (EFSA) highlighted extensions to the model required before it can be incorporated. This research begins to answer some questions asked in that review.
41
Williams, Ian. "Genetic aspects of a small scale honeybee breeding program." Thesis, Bangor University, 2013. https://research.bangor.ac.uk/portal/en/theses/genetic-aspects-of-a-small-scale-honeybee-breeding-program(95f9b751-17fe-442d-8bf6-6a7b7054ae6c).html.
Testo completoAbstract (sommario):
Beekeepers in Wales, like others across the northern hemisphere, continue to experience high overwintering colony losses. Breeding for local adaptation has been recommended as part of the solution. The West Wales Bee Breeding Program (WWBBP) was therefore established in an effort to improve, through selection, the resilience and production potential of a local bee stock. Breeding for desired character traits began in 2011 and focused mainly on colony strength, varroa mite infestation, and temperament. Foraging efficiency was also monitored when conditions allowed. This thesis presents data from the first two rounds of selection. Scant evidence indicating adaptive change due to selection was detected across this time frame, but a demonstrable reduction in the variance of colony strength was observed. The influence of selection across generations on population level genetic variation was also monitored. Microsatellite loci were highly polymorphic in the source population, and great diversity was also observed at a custom csd marker. Low frequency alleles at both marker types were lost across generations, and a significant difference in allelic richness was observed between the source population and each of the following two daughter generations. The effects of various selectionlbreeding parameters on the rate of genetic depletion due to selection within a contemporary timeframe (5 generations) were simulated, and the possible consequence of long term genetic depletion on adaptive response was considered. Simulations indicated that the number of breeder queens selected had the greatest influence on the rate of genetic depletion at both neutral loci and at the csd locus, across years. The WWBBP aims to enhance local suitability tlu'ough selective breeding while concurrently preserving genetic diversity and adaptive potential in the simplest most practical way. Hopefully, this thesis will help guide the future development of the program, and in addition, provide a basic transferable template for successful small-scale breeding.
42
Urlacher, Élodie. "A novel peptidergic pathway modulating learning in the honeybee." Toulouse 3, 2011. http://thesesups.ups-tlse.fr/1427/.
Testo completoAbstract (sommario):
Les processus cognitifs sont modulés par de nombreux facteurs, y compris des signaux sociaux émis par des congénères. Chez les insectes sociaux, les phéromones contribuent à organiser la vie de la colonie en modulant le comportement et la physiologie des individus. En utilisant l'abeille comme modèle pour étudier les bases neurales de l'apprentissage olfactif appétitif, nous montrons qu'il est modulé par une expérience sociale particulière, l'exposition à la phéromone d'alarme. Après exposition à ce signal ou à son composant principal (l'acétate d'isopentyle, IPA), les abeilles apprennent moins bien comparées aux contrôles. Ainsi, ceci déclencherait la libération de neuromodulateur(s) qui modifieraient le fonctionnement de régions cérébrales impliquées dans l'apprentissage. Des traitements pharmacologiques avant le conditionnement ont montré que des agonistes et un antagoniste des récepteurs opioïdes des mammifères peuvent respectivement mimer ou bloquer la modulation de l'apprentissage induite par l'IPA. Ceci suggère que l'exposition à l'IPA déclenche une voie de signalisation ayant des caractéristiques communes avec le système opioïde. Cependant, l'existence d'un tel système n'a jamais été démontrée chez l'invertébré. En se basant sur l'homologie de séquence avec des récepteurs opioïdes et des expériences pharmacologiques, nous avons identifié le récepteur à l'allatostatine C et ses ligands comme médiateurs potentiels des effets comportementaux de l'IPA. Nous proposons que l'action de ces neuropeptides fasse partie d'une réponse physiologique à des signaux d'alarme, de stress ou douloureux et puisse contribuer à l'efficacité de la défense collective de la ruche<br>Cognitive processes can be modulated by many factors, including social signals from conspecifics. In social insects, pheromones contribute to organize the life of the colony by modulating the behavior and physiology of individuals. Using the honeybee as a model organism to study the neural bases of learning, we show that appetitive olfactory learning is modulated by a particular social experience: exposure to the sting alarm pheromone. After exposure to this signal (released in life-threatening situations) or to its main pheromonal component (isopentyl acetate, IPA), bees perform less well in a Pavlovian conditioning assay, compared to unexposed bees. Thus, exposure to IPA may trigger some neuromodulator(s) that modify the function of the brain centers known to be involved in this task. Pharmacological treatments prior to conditioning show that agonists (fentanyl and morphine) and an antagonist (naloxone) of mammalian opioid receptors can mimic or reverse, respectively, the modulation of learning by IPA exposure. This suggests that exposure to the alarm pheromone triggers a signaling pathway sharing common features with the mammalian opioid system, as already proposed by others. However, its existence was never clearly demonstrated in invertebrates. Based on structural similarity with opioid receptors, as well as pharmacological experiments, we identified the allatostatin C receptor and its ligands as candidates for mediating IPA-induced behavioral effects. We argue that the action of such neuropeptides may be part of an adaptive physiological response to noxious and alarm/stress signals in the honeybee and may increase the efficiency of the collective defense of the hive
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Tan, Nguyen Quang. "Studies of the Asian giant honey bee, Apis dorsata fabricius (Apidae) in the submerged Melaleuca forest of Vietnam : biology, behaviour, ecology and apiculture." Thesis, University of Oxford, 2004. http://ora.ox.ac.uk/objects/uuid:96dea143-3c04-48a4-bceb-ccfc80db31c5.
Testo completoAbstract (sommario):
This thesis examines the bee, the plant and the human communities in the submerged Melaleuca forests of southern Vietnam. Chapter 1 gives a general introduction to the taxonomy and evolution of the genus Apis (honey bees), the research area and the general objectives of the thesis. Chapter 2 deals with biology of the Asian giant honey bee, Apis dorsata Fabricius and presents new data on the sizes and ratios of the drone and worker cells; the weight of the queen, drone and worker; and the egg production of A. dorsata queens. Chapter 3 demonstrates that properties of nest sites; such as the diameter, slope, length of the nest site, remnants of beeswax from the previous colony, and the size of the open space in front of the nest site, are criteria in the selection of nest sites by A. dorsata colonies. Chapter 4 discusses the floral relations of A. dorsata and other insect visitors in the forest. Three types of partitioning within and among plants and insects in the Melaleuca forest are found. These are the partitioning of visitors by Melaleuca cajuputi and Nypa fruticans flowers, the partitioning of visitation time by the two sympatric honey bee species, A. dorsata and A. florea, and the partitioning of visitation time on Melaleuca and Nypa flowers by either honey bee species. Results of Chapter 5 show that there is temporal partitioning of flower sources among the sympatric Asian honey bee species (A. dorsata, A. cerana and A. florea); however, there is a competition of flowers between the European bee (A. mellifera) and the Asian bee species. Chapter 6 discusses the important role of A. dorsata rafter beekeeping in forest protection, the conflicts between the beekeepers and new forest holders, and the economic efficiency of A. dorsata rafter beekeeping in comparison with those of A. mellifera and A. cerana beekeeping systems. Finally, Chapter 7 gives general conclusions of the thesis and recommendations for further study.
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Lloyd, Gerry Trevor. "Ultrastructural development in the corpus allatum of the adult worker honey bee." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1005480.
Testo completoAbstract (sommario):
The ultrastructure of the corpus allatum of the Cape worker honey bee has been examined in a systematic way during the first thirty days of adult life. Corpus allatum size in the Cape worker honey bee shows the age-dependent increase typical of the European worker honey bee, and in the Cape worker bee, the duration of increase is protracted. Analysis of ultrastructural development provides three indicators of metabolic status: mean mitochondrial size, "light and dark" cells, and extracted vacuoles. Significant fluctuations in mean mitochondrial size indicate a cyclical nature of cellular activity. New thought on the nature of "light and dark" cells proves that "dark" cells are almost certainly active in the process of JH biosynthesis, whilst "light" cells are definitely not active in JH biosynthesis. Extracted vacuoles found in corpus allatum cells during this study are thought to be remnants of lipid vacuoles, and the build up in number of these vacuoles is regarded as an indicator of reduced biosynthetic activity. Since the two indicators of decreased JH production ("light" cells and extracted vacuoles) co-exist with smaller mean mitochondrial size, larger mean mitochondrial size is taken as indicating increased levels of JH biosynthesis. Hence, fluctuations in mean mitochondrial size suggest cycles in the levels of JH production in individual corpora allata of the adult worker honey bee.
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Muller, W. J. "Wax secretion in the Cape honeybee (Apis mellifera capensis esch.) in relation to juvenile hormone and age polyethism." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1005485.
Testo completoAbstract (sommario):
Wax secretion in worker honeybees is significantly related to the age of the worker and, while the secretion pattern remains the same, the absolute amount of wax secreted varies seasonally. Comb building festoons, previously thought to be the site of wax secretion, contain only a fraction of the newly-secreted wax in the nest. Festooning behaviour was also found to be seasonal. The amount of wax secreted by workers was significantly affected by hive. Although age-related changes in behaviour and physiology of worker honeybees appears to be modulated by juvenile hormone (JH), wax secretion is not dependent on JH. Manipulating JH III titres by injecting the hormone and manipulating the only source of the hormone (the corpora allata: CA) did not affect wax secretion. Increasing haemolymph JH titre shortly after ec1osion did not affect the amount of wax produced by workers aged 3 to 21 days, nor could a critical period be found during which elevated hormone titres would affect the rate of wax secretion. Allatectomy of newly eclosed workers did not affect wax production. Removing the putative neural feedback inhibition on the CA did not result in a change in wax production. Implanting CA from older workers into younger workers had no significant effect. Methoprene, a widely-used JH analog, caused reduced wax secretion in workers. It is suggested that methoprene poisons worker honeybees. The results obtained are consistent with an alternative model for wax secretion proposed by Butler (1954). The methodological problems found in this work are present in many other studies. When viewed in this light, the role of JH in polyethism appears dubious and there are alternative models of polyethism that do not have these shortcomings.
46
Cole, H. "A computerised atlas of the honeybee brain (Apis mellifera L.)." Thesis, Bucks New University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376424.
Testo completo
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Wright, Emma. "The effect of pathogens on honeybee learning and foraging behaviour." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57266/.
Testo completoAbstract (sommario):
The European honeybee, Apis mellifera, is important economically not just for honey production but also as a pollinator. Bee pollinated plants contribute towards one third of the food eaten worldwide. However, honeybee numbers in some areas are declining. A range of interacting factors are thought to be involved, including pathogens and parasites, loss of forage, pesticide use, bad weather, and limited genetic variability. Pathogens are also known to cause changes in the behaviour of their hosts and these premortality and sublethal effects of disease may well play a role in colony declines and are the focus of this thesis. For individual bees the fungus Metarhizium anisopliae was used as a model pathogen and RT-Q-PCR was used to detect and quantify naturally occurring pathogens. In field colonies the level of infestation of the parasitic mite Varroa destructor was modified as a surrogate for disease load as the amounts of many viruses correlate with mite levels. Survival experiments showed that both disease load and forage availability had an effect on honeybee longevity and feeding the bees pollen increased their survival. Learning experiments showed that both the fungus and some of the bees’ naturally occurring pathogens caused changes in the learning ability of young adult and older forager bees. Young adult bees were better able to learn when infected with the fungus, possibly because it made them more responsive to the sucrose stimulus, whilst older forager bees where less able to learn when infected with the fungus. Harmonic radar was used to show that honeybee flight ability was affected by naturally occurring pathogens, especially deformed wing virus which caused bees to fly shorter distances and for shorter amounts of time than uninfected bees. Observation hives were used to study in-hive behaviour showing that bees with more pathogens were likely to start foraging earlier than healthier bees.
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Benjeddou, Mongi. "Molecular detection and genetic manipulation of the Black Queen Cell Virus." Thesis, University of the Western Cape, 2002. http://etd.uwc.ac.za/index.php?module=etd&.
Testo completoAbstract (sommario):
The South African isolate of the Black Queen-Cell Virus (BQCV), a honeybee virus, was previously found to have an 8550 nucleotide genome excluding the poly(A) tail. Its genome contained two ORFs, a 5'-proximal ORF encoding a putative replicase protein and a 3'-proximal ORF encoding a capsid polyprotein.<br />
<br />
A reverse transcriptase PCR (RT -PCR) assay was developed for the detection of BQCV and acute bee-paralysis virus (ABPV). Complete genomes sequences w ere used to design unique PCR primers within a l-kb region from the 3' end of both genomes to amplify a fragment of 70.0 bp from BQCV and 900 bp from ABPV. The combined guanidinium thiocyanate and silica membrane method was used to extract total RNA from samples of healthy and laboratory-infected bee pupae. In a blind test, RT-PCR successfully identified the samples containing BQCV and ABPV. Sensitivities were of the order of 130 genome equivalents of purified BQCV and 1600 genome equivalents of ABPV.
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Neumann, Peter. "Inter- and intraspecific parasitism in honeybees (Apis mellifera L.): the small hive beetle (Aethina tumida Murray) and the Cape honeybee (A. m. capensis Esch.)." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=975652702.
Testo completo
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Munn, Pamela A. "Structural studies on the Kenyon cells of the honeybee brain (Apis mellifera L.)." Thesis, Cardiff University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238212.
Testo completo