Submitted by Sandro Camargo (sandro.camargo@unipampa.edu.br) on 2015-05-07T22:33:38Z No. of bitstreams: 1 126110036.pdf: 2091532 bytes, checksum: 8020f2b19bedcc2aebd080e502846a88 (MD5) / Made available in DSpace on 2015-05-07T22:33:38Z (GMT). No. of bitstreams: 1 126110036.pdf: 2091532 bytes, checksum: 8020f2b19bedcc2aebd080e502846a88 (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 amostrasforam 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 fordetection 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.

Submitted by Ana Damasceno (ana.damasceno@unipampa.edu.br) on 2016-11-30T18:54:51Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Identificação de vírus que afetam apis mellifera associados ao ácaro ectoparasita varroa destructor em apiários do Rio Grande do Sul.pdf: 2079239 bytes, checksum: 490f111cf7ddb616e9d3cc3373a5be07 (MD5) / Made available in DSpace on 2016-11-30T18:54:51Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Identificação de vírus que afetam apis mellifera associados ao ácaro ectoparasita varroa destructor em apiários do Rio Grande do Sul.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.

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.

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.

No description available.

No description available.

African honeybee workers, Apis mellifera scutellata can activate their ovaries under queenless conditions to produce male (haploid) offspring. In contrast, laying workers of the Cape honeybee, Apis mellifera capensis, produce female (diploid) offspring via thelytokous parthenogenesis. In the early 1990’s colonies of A. m. capensis were transported into the distribution area of A. m. scutellata (corresponding to the summer rainfall region of South Africa), leading to the “capensis calamity”. Laying workers of A. m. capensis invaded and killed colonies of A. m. scutellata leading to losses of thousands of commercial colonies. A survey of the apiaries in the A. m. scutellata region was conducted over 18 months from 1997 to 1998, to determine the extent of the problem. It was found that the parasites were established in many apiaries throughout the distribution range of A. m. scutellata. As the problem seemed to be more severe with commercial and migratory beekeepers, the apiaries surveyed were divided into risk groups related to beekeeping practices. The low risk group included apiaries of beekeepers in areas that are separated from commercial beekeepers and their high risk activities. These low risk colonies were sedentary vs the migration to high risk ares eg. Aloes, sunflower pollination areas, citrus and other fruit pollination areas of the high risk apairies. The apiaries were monitored and records of the colonies’ condition were taken. Samples of workers were collected for dissection. It was found that the low risk group had a lower rate of infection, a higher production of brood and honey and a higher rate of survival over a 12 month period. The significant characteristics for identifying infection of a colony were determined as being the colour of the workers, the brood pattern, the presence of multiple eggs in cells and the presence of the queen. Indeed, the presence of dark workers with a black scutellum, an irregular brood pattern, the presence of multiple eggs in cells and the absence of queen were all prevalent in infected colonies. As sample of workers from all inspected colonies were dissected and the average ovariole counts as well of the development stage of the ovaries proved to be significant variables in the diagnosis. Other variables eg. Ovariole counts, spermatheca size and aggression proved to be not significant, but in conjunction with other variables, could be used for diagnosis. The genetic nature of the invasive parasitic population was determined using polymerase chain reaction (PCR) analysis. Nine loci were tested and the DNA fingerprints of all individuals sampled throughout the summer rainfall region were proved to be identical. This genetic identity led to the descripter of these individuals as a pseudoclone. In contrast, workers of A. m. scutellata were tested with the same loci and showed the normal distribution of an out-breeding population. In order to investigate the spread of the parasite within an apiary, colonies were exposed to heavily infected hives and inspected regularly. Ninety five percent of the colonies had either died or absconded within 12 months. It is concluded that this phenomenon of social parasitism is the consequence of apicaultural activities and that it can be managed by adopting low risk beekeeping practices. / Dissertation (MSc (Zoology and Entomology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

Orientador: Ricardo de Oliveira Orsi / Resumo: As abelhas melíferas são importantes agentes polinizadores em cultivos agrícolas e áreas de vegetação nativa e diretamente responsáveis pela produção apícola. Entretanto, grandes perdas de colônias manejadas vêm sendo registradas mundialmente, sendo a ampliação do uso de agrotóxicos uma das principais causas que pode estar associada a esse fenômeno. No presente trabalho, observou-se por meio de análises morfológicas, que a exposição de abelhas nutrizes em colônias, durante seis dias, a pastas de pólen contaminadas com doses ambientalmente relevantes do inseticida sistêmico fipronil (2,5 ppb) e fungicida piraclostrobina (850 ppb), isolados ou em associação, promoveu redução na altura das células secretoras das glândulas mandibulares; e que a associação dos agrotóxicos também reduziu o reservatório dessas glândulas. Nas glândulas hipofaringeanas, o número de ácinos que compõem a glândula não foi alterado, porém, a exposição aos agrotóxicos ocasionou redução na área dessas estruturas. Em conjunto, essas alterações podem reduzir a capacidade de secreção de geleia real pelas abelhas nutrizes. Estudos do proteoma da cabeça das abelhas utilizando a técnica 2D-PAGE para o fracionamento de proteínas, com identificação das proteínas em spots que apresentaram diferença de expressão (comparando grupos expostas e não-expostos aos agrotóxicos) por ESI-MS/MS, demonstraram alterações na expressão de proteínas pertencentes a família das principais proteínas geleia real (MRJPs); e de proteínas... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor

INTRODUCTION:Honey bees, Apis mellifera, have a diverse community of pathogens. Previous research has mostly focused on bacterial brood diseases of high virulence, but milder diseases caused by fungal pathogens have recently attracted more attention. This interest has been triggered by partial evidence that co-infection with multiple pathogens has the potential to accelerate honey bee mortality. In the present study we tested whether co-infection with closely related fungal brood-pathogen species that are either specialists or non-specialist results in higher host mortality than infections with a single specialist. We used a specially designed laboratory assay to expose honey bee larvae to controlled infections with spores of three Ascosphaera species: A. apis, the specialist pathogen that causes chalkbrood disease in honey bees, A. proliperda, a specialist pathogen that causes chalkbrood disease in solitary bees, and A. atra, a saprophytic fungus growing typically on pollen brood-provision masses of solitary bees.RESULTS:We show for the first time that single infection with a pollen fungus A. atra may induce some mortality and that co-infection with A. atra and A. apis resulted in higher mortality of honey bees compared to single infections with A. apis. However, similar single and mixed infections with A. proliperda did not increase brood mortality.CONCLUSION:Our results show that co-infection with a closely related fungal species can either increase or have no effect on host mortality, depending on the identity of the second species. Together with other studies suggesting that multiple interacting pathogens may be contributing to worldwide honey bee health declines, our results highlight the importance of studying effects of multiple infections, even when all interacting species are not known to be specialist pathogens.

Honey bee population decline has been attributed to a variety of causes including infestation of hives with Varroa destructor mites. Fluvalinate has been extensively used in the United States to combat these mites for nearly 30 years, despite its high toxicity to honey bees. The objectives of the current research project were to investigate the extent of fluvalinate contamination in commercially available wax and to define exposure pathways from the contaminated wax and fluvalinate-impregnated strips to larval and adult honey bees. All of the commercial wax tested in the current study contained elevated fluvalinate concentrations, ranging from 170 to 1040 ng/g wet weight, indicating a need for regulation of the sources of wax being rendered for resale. Based on the negative logarithm of the partition coefficient between wax and pollen (-0.54) and the fact that all of the tested wax samples contained elevated concentrations of fluvalinate, it is evident that fluvalinate has the potential to actively transfer from the contaminated wax into bee hive matrices. This point was confirmed by adding fluvalinate-dosed wax, fluvalinate-impregnated strips, or a combination of the two to 10-frame hives. Larvae and adult bees from those hives were checked for fluvalinate exposure using gas chromatography-mass spectrometry analysis. Larvae had detectable concentrations of fluvalinate in all three treatments. Bioaccumulation in adult bees was significantly affected by the interaction between treatment type and application time. In other words, residues were comparable from hives that only had fluvalinate-dosed wax to those that were actively being treated with impregnated strips, strongly suggesting that transfer of fluvalinate from wax into adult bees was an important exposure route. In conclusion, exposure of fluvalinate from contaminated wax and treatment strips to larvae and adult honey bees is an important factor that needs to be considered when applying miticides and evaluating risk in honey bee hives.