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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Inter- and intraspecific parasitism in honeybees (Apis mellifera L.): the small hive beetle (Aethina tumida Murray) and the Cape honeybee (A. m. capensis Esch.)

Neumann, Peter. January 2004 (has links) (PDF)
Halle, Wittenberg, University, Habil.-Schr., 2004.
2

Regulation of reproductive dominance hierarchies in Apis mellifera capensis workers

Simon, Ute. January 1998 (has links) (PDF)
Halle, University, Diss., 1998.
3

Studium fyziologie a hledání proteomických nástrojů pro supresi a detekci Varroa destructor / Study of physiology and searching of proteomic tools useful in suppression and detection of Varroa destructor

Holenková, Martina January 2012 (has links)
This work is focused on the study of physiology and proteome of the the mite Varroa destructor and on comparison with the honeybee Apis mellifera. Varroa is currently a major problem for beekeeping, because infects most of the colonies. The control of the mite can not be done without residues both in the hive and for example in the honey or other resources used by the man. Another problem can also be the simultaneously discussed issue of the connection with the Colony Collapse Disorder. The internal anatomy of V. destructor was studied by using paraffin histology. On histological sections stained using hematoxylin and PAS was possible to observe the mite digestive system, but also egg, ovaries or brain. The primary aim of this study was to identify the proteins of mite V. destructor and bee A. mellifera as a host of this parasite. For the electrophoretic separation was used two- dimensional gel electrophoresis, where the second dimension was carried out using 12% and 15% SDS-PAGE. The most abundant spots were selected for analysis using MALDI TOF/TOF mass spectrometry. The most abundant protein identified in samples of V. destructor was hexamerin, arginine kinase or hemelipoglycoprotein precursor. Hexamerins were also identified as the major proteins in the pupae samples. On the contrary the main...
4

The effect of apis mellifera and atropa belladonna on the human immune response

10 June 2009 (has links)
M.Tech.
5

Intra- and interspecific brood recognition in pure and mixed-species honeybee colonies, Apis cerana and A. mellifera

Tan, K, Yang, M-X, Radloff, S E, Yu, Y, Pirk, C W W, Hepburn, H R January 2009 (has links)
We studied the effects of mixed honeybee colonies of Apis mellifera and Apis cerana on the intraspecific and interspecific recognition of female brood stages in the honeybees A. cerana and A. mellifera by transferring brood combs between queenright colonies. In the intraspecific tests, significantly more larvae were removed in A. cerana than in A. mellifera, whilst significantly fewer eggs and pupae were removed in A. cerana than in A. mellifera. In the interspecific tests, A. cerana colonies removed significantly more larvae and pupae of A. mellifera than the same brood stages of A. cerana were removed by A. mellifera. We show there are highly significant differences in both intraspecific and interspecific brood recognition between A. cerana and A. mellifera and that brood recognition operates with decreasing intensity with increasing developmental age within species. This suggests that worker policing in egg removal is a first line of defense against heterospecific social parasites.
6

Identificação de vírus que afetam apis mellifera associados ao ácaro ectoparasita varroa destructor em apiários do Rio Grande do Sul

Garcia, Fernanda Wiesel 30 April 2014 (has links)
Submitted by Ana Damasceno (ana.damasceno@unipampa.edu.br) on 2016-10-13T18:21:12Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Identificacao de virus que afetam apis mellifera.pdf: 2079239 bytes, checksum: 490f111cf7ddb616e9d3cc3373a5be07 (MD5) / Made available in DSpace on 2016-10-13T18:21:12Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Identificacao de virus que afetam apis mellifera.pdf: 2079239 bytes, checksum: 490f111cf7ddb616e9d3cc3373a5be07 (MD5) Previous issue date: 2014-04-30 / A apicultura é uma atividade de importância econômica e ambiental. O clima e a flora do Brasil somados à presença da abelha africanizada conferem um excelente potencial apícola. Entretanto, as abelhas são suscetíveis a uma variedade de doenças. Vários são os patógenos que podem acometer abelhas melíferas, sendo o foco deste trabalho a relação entre o ácaro Varroa destructor e os vírus que acometem abelhas. V. destructor é um ectoparasita, sendo a varroose, doença causada por este ácaro, responsável pela mortalidade de milhares de colônias de Apis mellifera em várias partes do mundo. Entretanto, os danos causados pela varroose variam com a raça de abelhas e condições climáticas. Embora o ácaro cause poucos danos nas colônias de abelhas africanizadas no Brasil, a coexistência deste ectoparasita com determinados tipos virais pode comprometer seriamente a saúde da colônia, uma vez que muitos destes vírus tem sua transmissão relacionada ao ectoparasita, apontando este como um vetor da infecção. Portanto, faz-se necessária a identificação de quais vírus estão associados ao ácaro e que, possivelmente, utilizam-se do ácaro como vetor. Dentro deste contexto, objetivamos verificar a existência de vírus associados ao ácaro V. destructor em espécimes coletadas em apiários de diferentes regiões do Rio Grande do Sul. Foram realizadas coletas de ácaros em apiários localizados em oito municípios gaúchos. A partir das amostras coletadas, foi realizada extração de RNA total e síntese de cDNA. O cDNA sintetizado foi submetido à PCR utilizando-se 9 pares de primers para detecção de vírus que afetam abelhas e um par de primers para controle endógeno. As amostras foram submetidas a eletroforese em gel de agarose. Identificou-se, em três apiários, a presença dos vírus SBV (Vírus da Cria Ensacada) e VDV-1 (Vírus Varroa destructor-1) associados ao ácaro V. destructor. Estes dados são inéditos uma vez que estudos semelhantes nunca foram realizados no Brasil ou em abelhas africanizadas e poderão servir de base no desenvolvimento de programas de controle deste parasita. / Beekeeping is an activity that has both economic and environmental importance. Brazil has excellent climate and flora for beekeeping, and alongside the presence of Africanized bee populations, it has great potential for apiculture. However, Apis mellifera bees are susceptible to a variety of diseases. There are several pathogens that can affect honeybees and the focus of this work is to assess the relationship between the Varroa destructor mite and viruses that affect bees in the state of Rio Grande do Sul. V. destructor is an ectoparasite and the disease caused by this mite may be responsible for the death of thousands of colonies of A. mellifera in several parts of the world. However, the damage caused by the varroa mite vary according to the race of the affected bees and weather conditions. Although the varroa mite cause little damage in colonies of Africanized bees in Brazil, the coexistence of this ectoparasite with certain types of viruses can seriously compromise the health of the colony, since many of these viruses use the mite for transmission, pointing this as a probable vector. Therefore, it is necessary to identify which viruses are associated with the mite and that possibly use it as vector. Within this context, the objective of this work is to verify the presence of viruses associated with the V. destructor mite in specimens collected in apiaries in different regions of Rio Grande do Sul. Mite collections were made in apiaries located in eight different cities in the state. Collected samples were subjected to total RNA extrection and cDNA synthesis was performed. The synthesized cDNA was subjected to PCR using nine primer pairs for detection of viruses affecting bee and one pair of primers for endogenous control. Amplified samples were subjected to electrophoresis on agarose gel. With this work, we have been able to identify in the presence of SBV and VDV-1 virus associated with V. destructor mite in three different apiaries. The obtained data are novel, since similar studies have never been conducted before in Brazil or using Africanized bee colonies, and could be used as basis in development of control strategies of this parasite.
7

Breeding of Hygienic Disease Resistant Bees

Lapidge, Keryn Lea January 2002 (has links)
Hygienic behaviour in the honeybee (Apis mellifera) has been shown to be an effective control mechanism against brood diseases such as chalkbrood and AFB. Chalkbrood has proven to be problematic for the Australian honey industry since it was identified here in 1993. Hygienic behaviour is a much studied trait. Rothenbuhler investigated the genetic basis of hygienic behaviour, proposing a two-gene model to explain the uncapping and removal of dead brood. His elegant experiment remains the textbook example of a behavioural genetic study. Although this model has been challenged, it is still generally agreed that a small number of unlinked genes produce a large effect on hygienic behaviour, that hygienic alleles are recessive and are inherited in a Mendelian manner. Experimental backcross colonies were produced from an inbred hygienic line and an inbred non-hygienic line, both provided by Dr. Marla Spivak, University of Minnesota. These backcross colonies were assessed for hygienic behaviour using a standard assay. Statistical analyses of the field data indicated that the genetic basis of the trait was more complex than either the simple Mendelian and widely accepted two-gene or three-gene models that have been proposed previously. Molecular techniques, linkage mapping and QTL analysis then were employed to determine how many loci directly influence hygienic behaviour and the relative level of influence and location of each locus within the genome of A. mellifera. Full multipoint linkage analysis by Mapmaker v3.0 software produced a new genetic map of the honeybee comprised of 358 marker loci ordered over 25 linkage groups spanning a total distance of 3406.2 cM. The average distance between each marker was 9.5 cM. QTL analysis of the experimental data identified seven putative genetic markers associated with hygienic behaviour. QTLs located on linkage groups 2, 4, 6 and 22 were detected for both overall hygienic behaviour and uncapping behaviour only. Individually, each QTL is of relatively small effect with each explaining only 9% � 15% of the variance in hygienic levels observed. Collectively, the putative QTLs identified here explain 79.4% of the observed variance in the expression of hygienic behaviour. These results indicate that there are many genes of low to moderate effect rather than few genes of large effect involved in this complex behavioural trait. This is typical of inherited quantitative traits which do not exhibit Mendelian phenotypic ratios. DNA extracted from the brood samples taken during testing of commercial stock, and from individual bees identified as either highly hygienic or non-hygienic in a reciprocal backcross experiment, were screened with the candidate markers associated with putative QTLs to test their diagnostic power. Unfortunately, none have produced reliably diagnostic DNA profiles. As we have now shown that hygienic behaviour is a polygenic, quantitative trait, simple diagnostic markers for Rothenbuhler's 'uncapping' and 'removal' genes are unlikely to be achieved. Our results show that the most likely way to improve disease resistance in Australian stock is via traditional methods of recurrent selection. The project was responsible for the importation of new genetic material into Australia from the United States. This hygienic stock has been well received by industry, has been widely disseminated, and incorporated into local breeding programs. We hope that it has lead to a general improvement in the level of disease resistance in Australian commercial bees.
8

Breeding of Hygienic Disease Resistant Bees

Lapidge, Keryn Lea January 2002 (has links)
Hygienic behaviour in the honeybee (Apis mellifera) has been shown to be an effective control mechanism against brood diseases such as chalkbrood and AFB. Chalkbrood has proven to be problematic for the Australian honey industry since it was identified here in 1993. Hygienic behaviour is a much studied trait. Rothenbuhler investigated the genetic basis of hygienic behaviour, proposing a two-gene model to explain the uncapping and removal of dead brood. His elegant experiment remains the textbook example of a behavioural genetic study. Although this model has been challenged, it is still generally agreed that a small number of unlinked genes produce a large effect on hygienic behaviour, that hygienic alleles are recessive and are inherited in a Mendelian manner. Experimental backcross colonies were produced from an inbred hygienic line and an inbred non-hygienic line, both provided by Dr. Marla Spivak, University of Minnesota. These backcross colonies were assessed for hygienic behaviour using a standard assay. Statistical analyses of the field data indicated that the genetic basis of the trait was more complex than either the simple Mendelian and widely accepted two-gene or three-gene models that have been proposed previously. Molecular techniques, linkage mapping and QTL analysis then were employed to determine how many loci directly influence hygienic behaviour and the relative level of influence and location of each locus within the genome of A. mellifera. Full multipoint linkage analysis by Mapmaker v3.0 software produced a new genetic map of the honeybee comprised of 358 marker loci ordered over 25 linkage groups spanning a total distance of 3406.2 cM. The average distance between each marker was 9.5 cM. QTL analysis of the experimental data identified seven putative genetic markers associated with hygienic behaviour. QTLs located on linkage groups 2, 4, 6 and 22 were detected for both overall hygienic behaviour and uncapping behaviour only. Individually, each QTL is of relatively small effect with each explaining only 9% � 15% of the variance in hygienic levels observed. Collectively, the putative QTLs identified here explain 79.4% of the observed variance in the expression of hygienic behaviour. These results indicate that there are many genes of low to moderate effect rather than few genes of large effect involved in this complex behavioural trait. This is typical of inherited quantitative traits which do not exhibit Mendelian phenotypic ratios. DNA extracted from the brood samples taken during testing of commercial stock, and from individual bees identified as either highly hygienic or non-hygienic in a reciprocal backcross experiment, were screened with the candidate markers associated with putative QTLs to test their diagnostic power. Unfortunately, none have produced reliably diagnostic DNA profiles. As we have now shown that hygienic behaviour is a polygenic, quantitative trait, simple diagnostic markers for Rothenbuhler's 'uncapping' and 'removal' genes are unlikely to be achieved. Our results show that the most likely way to improve disease resistance in Australian stock is via traditional methods of recurrent selection. The project was responsible for the importation of new genetic material into Australia from the United States. This hygienic stock has been well received by industry, has been widely disseminated, and incorporated into local breeding programs. We hope that it has lead to a general improvement in the level of disease resistance in Australian commercial bees.
9

Kvantitativní pylová analýza medu

Melecká, Ilona January 2006 (has links)
No description available.
10

Kvalitativní pylová analýza medu

Novotná, Helena January 2006 (has links)
No description available.

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