Actuellement, l’ectoparasite Varroa destructor est considéré comme la plus grande menace pathogène pesant sur la survie de l’Abeille mellifère (Apis mellifera). En plus d’engendrer des dommages directs aux abeilles par la consommation répétitive de leur corps gras et de leur hémolymphe et par la dépression de leur système immunitaire, les varroas affectent également indirectement les abeilles par la transmission de plusieurs agents pathogènes viraux. En absence de traitements périodiques, la plupart des colonies d’abeilles mellifères s’effondrent dans une période de deux ou trois années suivant l’infestation initiale de Varroas. Face à la pression sélective engendrée par cet Acarien, certaines colonies d’abeilles mellifères ont développé des comportements de résistance. Parmi ces comportements, nous retrouvons le Varroa Sensitive Hygiene (VSH) qui permet aux ouvrières de détecter la présence du parasite dans le couvain d’abeille et de le retirer. De plus, ce comportement est également fortement associé au trait Suppressied Mite Reproduction (SMR), c’est-à-dire, à la baisse du succès reproducteur des varroas dans le couvain d’abeille. Ainsi, les abeilles dotées du comportement VSH sont capables de réduire le niveau d’infestation de leur ruche et de le maintenir à un faible niveau. C’est pourquoi la sélection d’abeilles ayant ce trait comportemental pourrait s’avérer être une solution efficace et durable pour pallier les problèmes engendrés par le Varroa. Cependant, la sélection pour un caractère comporte un certain risque puisqu’il peut advenir que la sélection d’un trait engendre également des répercussions négatives sur d’autres caractères désirables. C’est pourquoi un des objectifs de ce projet est de confirmer la relation entre le VSH et le SMR, et de déterminer les facteurs probables engendrant les problèmes de fertilité du Varroa. Le second objectif quant à lui est de déterminer si la sélection du comportement VSH permet aux colonies de combattre efficacement les varroas sans que cela porte atteinte à la sélection d’autres critères importants en apiculture. / Currently, the ectoparasite Varroa destructor is considered to be the greatest threat to the survival oft he honey bee (Apis mellifera). In addition to causing direct damage to bees through repeated consumption of their fat bodies and depression of their immune system, Varroa also indirectly affects bees through the transmission of several pathogens. In the absence of periodic treatment, most honeybee colonies collapse within two to three years of the initial Varroa infestation. Faced with the selective pressure generated by this mite, some colonies of honey bees have developed a resistance behavior.This behavior, called Varroa Sensitive Hygiene (VSH), allows workers to detect the presence of the parasite in bee brood and remove it. In addition, this behavior is also strongly associated with theSuppressed Mite Reproduction (SMR) trait, i.e., the decrease in Varroa reproduction in bee brood. Thus, bees with VSH behavior are able to reduce the level of infestation of their hive and maintain it at a low level. Therefore, the selection of bees with this behavioral trait could prove to be an effective and sustainable solution to the problems caused by varroas. However, selecting for a trait involves a certain risk since it may happen that the selection of a trait also has a negative impact on other desirable traits.Therefore, the first objective of this project is to confirm the relationship between VSH and SMR, and to determine the likely factors leading to mite fertility problems. The second objective is to determine whether the selection of VSH behavior allows colonies to effectively control Varroa without compromising the selection of other important criteria in beekeeping.

Madagascar figure parmi les cinq premiers pays « hot spots » prioritaires pour la conservation de la biodiversité mondiale, Apis mellifera unicolor est son abeille endémique. Depuis 2010, V. destructor a été introduit à Madagascar. Les objectifs de cette thèse étaient : d'étudier la diversité et la structure génétique de l'abeille A. m. unicolor et de l'acarien V. destructor, d'évaluer l'impact de V. destructor sur les colonies, d'étudier le comportement hygiénique des colonies. Nos résultats confirment que l'ensemble des échantillons collectés font partie de la lignée africaine, plus de 99% ont été identifiés comme A. m. unicolor. Malgré sa faible diversité nucléaire, les populations présentent une structuration génétique organisée en deux sous clusters correspondant à des régions géographiques. Un seul haplotype de V. destructor a été détecté, l'haplotype coréen (K1-1). Les études génétiques ont montré une proportion élevée de génotype homozygote (69.5%) et un nombre élevé de MLG sur les Hauts Plateaux par rapport à la côte Est. La présence de MLG particulier sur les Hauts Plateaux conforte l'hypothèse de son introduction dans la capitale. La propagation de V. destructor à Madagascar est relativement lente, sa dispersion reste encore confinée à certaines régions des Hauts Plateaux et de la côte Est. L'impact de parasite est sévère, en un an, la perte des colonies infestées est estimée à 60 %. En se basant sur le pourcentage des cellules nettoyées après 6 h de test à l'aiguille, l'efficacité des colonies à détecter et à désoperculer les cellules est comparable à celles des abeilles hygiéniques africanisées et semble beaucoup plus élevée que celle des abeilles européennes. La présence de colonies hautement hygiéniques au sein des populations offre une opportunité pour un futur programme de sélection de souches tolérantes. / Madagascar is among the top five priorities "hotspots" for global biodiversity conservation. Apis mellifera unicolor was an endemic honey bee. In 2010, Varroa destructor has been reported parasitizing A. m. unicolor. Objectives of this thesis were i) to study the genetic diversity and structure of both A. m. unicolor and V. destructor, ii) to estimate the impact of V. destructor on colonies, and iii) to investigate the hygienic behaviour of colonies. Our results confirm that all honey bees collected belonged to the African lineage and more than 99% were identified as A. m. unicolor. Despite its low nuclear genetic diversity, two genetic clusters have been detected, corresponding to geographic regions. Only one haplotype of V. destructor was detected, the Korean haplotype (K1-1). Genetic studies showed a higher proportion of homozygous genotype (69.5%) and a high number of MLG (Multi- Locus Genotypes) in the High Lands compared to the East coast. The presence of particular MLG on the High Land reinforces the assumption of its introduction into the capital. The spread of V. destructor in Madagascar is relatively slow, its presence remains confined to the High Land and the East coast. The impact of the parasite on A. m. unicolor was severe; with about 60% of colony losses in a year reported. Based on the percentage of cleaned cells observed 6 hour after pin killing broods, the efficiency colonies to detect and uncap cells was comparable to those of Africanised hygienic honey bees and was much higher than those of European honey bees. The detection of highly hygienic colonies is a great opportunity to develop a programme of selection of tolerant honey bee strains.

Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-11Bitstream added on 2014-06-13T20:44:28Z : No. of bitstreams: 1 castagnino_glb_dr_botfvmz.pdf: 159555 bytes, checksum: 0d4941b05eba8f37f9e2e42101623105 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O presente trabalho teve como objetivo avaliar os efeitos do ácido oxálico e de óleos essenciais de plantas como arruda (Ruta graveolens), timol (Thymus vulgaris) eucalipto (Eucalyptus spp) e hortelã (Mentha piperita) na infestação do Varroa destructor em colônias de abelhas Apis mellifera africanizadas. Testes in vitro foram realizados para verificar o efeito desses produtos sobre as abelhas e os ácaros Varroa destructor. Vinte abelhas foram colocadas em gaiola de observação e, no seu interior, um bloco de esponja floral com 10μL, 50μL e 200μL dos diferentes óleos essenciais, segundo os tratamentos: T0: água, T1: óleo de arruda, T2: óleo de hortelã, T3: timol e T4: óleo essencial de eucalipto. Após, as abelhas e os ácaros foram observados por seis horas e quantificadas as mortalidades em decorrência do efeito de cada tratamento. Ambos os testes in vitro foram constituídos de quatro repetições por tratamento. No trabalho de campo, foram realizados seis tratamentos com cinco repetições, aplicados em 30 colônias, sendo: (T0) colméias sem tratamento; (T1) colméias tratadas com óleo essencial de arruda; (T2) timol; (T3) ácido oxálico; (T4) óleo essencial de eucalipto e (T5) óleo de hortelã. Os dados coletados antes da aplicação de cada produto foram confrontados com os obtidos após, verificando os diferentes níveis de mortalidade de varroas, taxa de mortalidade de crias de abelhas, taxa de infestação de varroas em crias e em abelhas adultas. Testes in vitro demonstraram que as substâncias testadas promoveram a mortalidade dos ácaros a partir de 10μL. Em trabalho de campo, constatou-se que as colônias tratadas com óleo de arruda, timol, ácido oxálico, óleo de eucalipto e de hortelã reduziram de forma significativa a mortalidade de crias quando parasitadas pelo ácaro. Os tratamentos com ácido... / This study aimed to evaluate the effects of oxalic acid, and plant essential oils such as arruda (Ruta graveolens), thymol (Thymus vulgaris), eucalyptus (Eucalyptus spp) and mint (Mentha piperita) in the Varroa destructor infestation in hives of honeybees Apis mellifera africanizated. In vitro tests were performed to determine the effect of these products on bees and Varroa destructor mite. Twenty bees were allocated in observational cages and inside a block of floral foam with 10μL, 50 μL and L 200 μL of different essential oils, according to the treatments: T0: water, T1: arruda oil, T2: mint oil, T3: thymol and T4: eucalyptus essential oil. Afterward, the bees and mites were observed for six hours and mortality recorded. Both in vitro tests were performed in quadruplicate measurements per treatment. Field study was conducted in Santana do Livramento / RS, from 20th June to 21st July, 2005. Six treatments with five repetitions were performed in 30 colonies, where: (T0) beehives without treatment; (T1) beehives treated with arruda essential oil, (T2) thymol, (T3) oxalic acid, (T4) eucalyptus essential oil, and (T5) mint oil. Data collected before the implementation of each product were confronted with those obtained after products administration, checking the different levels of varroas mortality, mortality rate of young bees, infestation rate of varroas in young and adult bees. In vitro tests showed that the tested substances promoted bees and mites mortality in equal or superior amounts of 10μL. In this context, it was found that the colonies treated with arruda oil, thymol, oxalic acid, eucalyptus and mint oil reduced significantly mortality of mite parasitized young bees. Treatments with oxalic acid and thymol promoted a significant reduction in varroas infestation... (Complete abstract click electronic access below)

This thesis analyzes mixtures of neem oil and amitraz as alternative control for Varroa destructor, a major pest of Apis mellifera, under different agricultural settings. In organic and conventional farms, the different treatments were applied in colonies to determine impacts on mite loss, colony strength, and honey yield. The results demonstrated neem to have the least effective control on mite mortality, while the neem and amitraz mixture had the most. Furthermore, no long term impacts on queen fecundity and colony strength were noticed between treatments. However, queen fecundity and honey yield was significantly higher in sites with higher flower abundance and diversity, demonstrating higher colony strength in these sites. Further understanding of the relationship between apiculture and agricultural management is vital for conservation of pollinator health and associated habitats.

Microbiomes are an extremely vast and complex network of microorganisms. Bacteriophages are a key factor in the microbial health of an ecological system and impact the evolution of pathogenic bacterial strains. Bacteria and the phages that infect them have an intricate relationship due to the dependency on the bacterial host for phage replication, the ability of the phage to lyse and kill its host, and the horizontal gene transfer between the host and phage. This thesis aimed to understand how bacteria and the bacteriophages that infect them impact an ecological system, with a focus on disease states. By analyzing all bacteriophages targeting a specific host, genomic properties, physical similarities and differences a better understanding of how a group of tailed phages have evolved numerous mechanisms and tools to infect host bacteria was understood. The microbiome study of the Western honey bee Apis mellifera, comparing the microbial communities of colonies infested with the external parasite Varroa destructor against those not infested revealed a need for more directed treatment of Varroa infestations. Through our study we discovered that the honey bee microbiome is much more complex than previously reported, consisting of hundreds of bacterial species. In addition, through comparing infested and healthy colonies, we discovered that infestation of Varroa destructor mites negatively impact the colony microbiome in part by reducing microbes key in digestion and immune health of honey bees. Results in this thesis indicate that two microbes which have not been previously established as part of the key microbes in honey bee guts, Xenorhabdus and Sodalis, may in fact be key to honey bee health as they were both effected negatively by the presence of Varroa mite infestations. These bacteria have been shown to be involved in immune health in other insects, supporting this hypothesis. The final stage of this thesis involved the development of an acaricide bacteriophage therapy designed to target key microbes in the gut of V. destructor. Our therapy was shown to safely treat honey bee colonies infested with this parasite. It can be concluded that while phages are a normal part of the microbial ecosystem of the intestinal tract of organisms, altering that balance by increasing the phage load on the microbiome to target specific beneficial microbes drastically reduces the overall fitness of the organism. Results from this study indicate that multi-target cocktail and single-target phage therapy are an effective low impact biological Varroacide. The discovery of an effective therapy is important and to better understand the results of this thesis, further investigation is required, including a study of the impact of the phage therapy on the mite microbiome, as well as the safety of the therapy to humans.

Throughout the last five decades, European Honey bee (Apis mellifera) colonies have been heavily damaged by invading Varroa mites (Varroa destructor), and, more recently, small hive beetles (Aethina tumida). These pests infest A. mellifera colonies throughout Virginia, with V. destructor feeding upon the lipids of their hosts and spreading viruses, and A. tumida feeding extensively on hive products and brood. Because V. destructor has historically demonstrated acaricide resistance, this study examined V. destructor resistance to three common acaricides (amitraz, coumaphos, and tau-fluvalinate) throughout the three geographic regions of Virginia using glass vial contact bioassays; the results showed no resistance in the sites tested. To gain better insights into A. tumida pharmacology, several known acetylcholinesterase (AChE) inhibitors and three novel insecticides (previously shown to have low mammalian toxicity) were tested against an A. tumida laboratory colony through in vivo and in vitro bioassays. The results of these bioassays indicated that coumaphos was most selective and topically effective against A. tumida, while only one experimental compound was selective against A. tumida, with 29-fold less potency than coumaphos. These results can help apiculturists in making informed pest management choices and can lead to future studies further examining V. destructor resistance and optimizing A. tumida insecticide treatments. / Master of Science in Life Sciences / Beekeepers throughout the world have experienced great economic loss and observed a troubling decline in European Honey bee colonies over the past fifty years due to Varroa mite infestations. Varroa mites feed on the fat body of bees, depriving them of nutrients and infecting them with various diseases. Attempts made to control Varroa mites with synthetic chemicals throughout the years have led to acaricide resistance. To look at resistance in Virginia’s mite populations, resistance testing was performed on Varroa mite populations throughout the three geographic regions of Virginia, and these studies showed that there was not resistance in these populations. Another significant hive pest that is increasingly prevalent in the United States is the small hive beetle (SHB), which feeds on bee brood and hive products. SHB management tactics are still being explored, and this project tested various known insecticide treatments against small hive beetles and bees, as well as three insecticide treatments that were designed for mosquito control and have low toxicity to mammals. The results of this study showed that, of the insecticides tested, coumaphos was the most selective against SHB. This information can help beekeepers in Virginia make informed choices when deciding how to treat Varroa mite infestations, and can add to the knowledge base of those fighting small hive beetle infestations.

La sélection génétique d'abeilles mellifères (Apis mellifera) offre à l'industrie apicole la possibilité de combattre le parasite Varroa destructor et ainsi réduire la dépendance envers les acaricides. En effet, certaines populations d'abeilles possèdent des traits comportementaux hygiéniques héritables qui leur permettent de résister au Varroa. Cependant, les liens entre ces différents traits comportementaux ne sont pas encore bien définis, ce qui limite le progrès génétique. Dans ce contexte, nous avons mesuré les traits comportementaux de résistance au Varroa suivants : les tests de mort du couvain par congélation (freeze-kill brood assay, FKB) et de l'aiguille (pin-kill brood assay, PKB), le varroa-sensitive hygiene (VSH), le retrait des pupes, le mite non-reproduction (MNR) et la réoperculation des cellules de couvain. Ces mesures ont été utilisées pour calculer les corrélations et deux d'entre elles étaient négatives et significatives: (1) entre la réoperculation des cellules infestées par le Varroa et la réoperculation totale et (2) entre la réoperculation des cellules infestées par varroa et le varroa-sensitive hygiene (VSH). Nous avons également sélectionné le meilleur modèle prédictif des niveaux d'infestation par le varroa dans les colonies en utilisant l'approche « step-wise » basée sur le critère AIC. Notre modèle révèle que le MNR et le FKB sont significativement liés à la population de varroas avec une relation négative, tandis que la réoperculation était significativement liée à des niveaux d'infestation de varroas avec une relation positive. Ainsi, les scores MNR ou FKB plus élevés sont significativement reliés à de faibles niveaux d'infestation d'acariens dans les colonies à la fin août, tandis qu'une activité de réoperculation des cellules de couvain plus élevée est significativement reliée à un niveau d'infestation élevé d'acariens dans les colonies. Notre travail indique que le comportement de réoperculation pourrait être un trait de caractère utile pour aider la sélection de lignées d'abeilles résistante à Varroa mais que d'autres travaux doivent être faits pour mieux comprendre sa signification. / The genetic selection of honeybees (Apis mellifera) offers the beekeeping industry the possibility of combating the Varroa destructor parasite and thus reducing its dependence on acaricides. Indeed, some bee populations have heritable hygienic behavioural traits that allow them to resist Varroa infestation. However, the links between these different behavioural traits are not yet well defined, which limits genetic progress. In this context, we measured the following behavioural Varroa resistance traits: freeze-kill brood assay (FKB) and pin-kill brood assay (PKB), varroa-sensitive hygiene (VSH), pupae removal, mite non-reproduction (MNR) and recapping activity. Correlations between these measures show that two are negative and significant: (1) between the recapping of cells infested with Varroa and the total number of recapped cells and (2) between the recapping of cells infested with Varroa and varroa-sensitive hygiene (VSH). We also selected the best predictive model of varroa infestation levels using the "step-wise" approach based on the AIC criterion. Our model revealed that MNR and FKB were significantly related to the varroa population levels with a negative relationship, while recapping was significantly related to mite infestation levels with a positive relationship. Thus, a higher MNR or FKB score is significantly related to low levels of mite infestation in colonies at the end of August, while a higher recapping activity is significantly related to a high level of mite infestation. Our work indicates that recapping behavior could be a useful trait to aid the selection of Varroa-resistant bee lines but that further work needs to be done to better understand its significance.

A apicultura brasileira melhorou muito após a introdução da abelha africana em 1956 pelo geneticista Warwick Kerr e a ocorrência da sua hibridização com as abelhas europeias já presentes no país. Entre outras vantagens, esta abelha híbrida ou Africanizada é relativamente resistente às doenças e parasitas que normalmente afligem as abelhas. A apicultura depende de recursos naturais e apresenta oscilações de produção de acordo com as condições do clima e ambiente regionais. Em épocas de ausência de floradas, a reserva de alimento na colônia é insuficiente e o fornecimento de alimentação artificial às abelhas torna-se aconselhável. Vários estudos com suplementações proteicas para abelhas têm sido realizados com a finalidade de proporcionar maior nutrição nos períodos de escassez de alimento no campo. Entretanto, há de se avaliar também os efeitos destes suplementos nas populações parasitárias das abelhas, como a do ácaro Varroa destructor. Este ácaro constitui uma importante praga e está presente praticamente no mundo todo. Os objetivos principais deste estudo consistiram em avaliar a dinâmica da população de V. destructor quanto aos graus de infestação e reprodução em colônias de abelhas Africanizadas localizadas em um apiário de Ribeirão Preto-SP, relacionando com as principais variáveis climáticas (primeira etapa) e com o fornecimento de dieta proteica complementar (segunda etapa). De agosto de 2013 a outubro de 2016, foram realizados experimentos com abelhas operárias, tanto em adultas (1ª etapa) como em crias (1ª e 2ª etapas). Para a segunda etapa, considerou-se também as variáveis de mapeamento das colônias, como pólen, néctar, cria aberta e cria operculada e as variáveis de sazonalidade, levando-se em conta as quatro estações do ano. Para ambas as etapas observou-se a presença ou ausência natural de rainha nas colônias e sua influência sobre a infestação e reprodução de varroas. Os resultados mostraram, quanto às variáveis climáticas, relação significativa e negativa da temperatura do ar com a infestação de varroas nas abelhas adultas. A umidade relativa do ar apresentou relação significativa e positiva com a infestação do ácaro, tanto em adultas como nas crias. Nenhuma variável climática considerada neste estudo (temperatura, umidade ou precipitação), mostrou evidência de influência sobre a reprodução dos ácaros. Houve um aumento de mais de 3% no grau de infestação de varroas nas crias de abelhas em colônias que receberam a dieta proteica adicional (de 7,83% para 10,97%), em comparação às colônias controle. Entretanto, este aumento não foi significativo. Quanto à reprodução de varroas, o fornecimento da dieta proteica apresentou influência significativa sobre o aumento do número de ácaros encontrados por célula infestada, somente nos meses de setembro de 2015 e fevereiro de 2016. As variáveis de mapeamento apresentaram relação significativa com a infestação de varroas, sendo negativa quanto ao pólen ou crias abertas e positiva quanto ao néctar ou crias operculadas. Nenhuma dessas variáveis apresentaram efeitos significativos sobre a reprodução de varroas. As infestações de varroas foram maiores no outono, em seguida o verão, o inverno e a primavera. Houve diferença significativa entre os valores de infestação entre as estações, exceto entre verão e outono e entre inverno e primavera. A reprodução do ácaro foi maior no outono e em seguida o inverno, o verão e a primavera. Não houve diferença significativa na reprodução do ácaro somente entre as estações verão e primavera. A ausência de rainha influenciou significativamente no aumento da infestação de ácaros na segunda etapa dos experimentos. / Brazilian beekeeping improved considerably after the introduction of the African bee in 1956 by the geneticist Warwick Kerr and its hybridization with the European honey bees that had been introduced in the 1800s. Among other advantages, this hybrid or Africanized bee is relatively resistant to the diseases and parasites that normally affect bees. Apiculture depends on natural resources, which vary with climate and regional environment. When there is a lack of flowers in the field, food reserves in the colony can soon become insufficient. Under such conditions, it is advisable to offer artificial feed to the bees. Various studies with protein supplements have been conducted to provide improved nutrition, especially during dearth periods. However, it is important to determine how such supplements may affect bee health, including infestation with bee parasites, such as the mite Varroa destructor. This mite is an important pest worldwide. Our objectives were to examine the population dynamics of V. destructor in Africanized honey bee colonies in Brazil, as a function of climate and colony factors and of feeding with protein diets. From August 2013 to October 2016, infestations were investigated in adult bees and in honey bee brood. Maps were made of the allocations of pollen, nectar, open and sealed brood in the combs. Data was also taken concerning climate variables during the four seasons. The effect of the presence versus absence of the queen was also investigated through hive manipulations. There was a significant negative correlation of infestation on adult bees with air temperature. Relative humidity was significantly correlated with infestations of the mite on adult bees and in the brood. None of the three climate variables measured (temperature, humidity and rainfall) significantly affected mite reproduction. Brood infestation rates were increased in colonies that were fed a protein diet (10.9 versus 7.83%); however, this difference was not significant. The mean number of mites per bee brood cell was significantly greater in colonies fed a protein diet during only two months of the study, these being September 2015 and February 2016. Some of the mapping variables were significantly correlated with mite infestation. There was a negative correlation of pollen and unsealed brood area with infestation rate, while mite infestation rate was positively correlated with nectar and sealed brood areas. None of the mapping variables was significantly correlated with mite reproduction. Infestation rates were highest in autumn, followed by summer, winter and spring. Mite reproduction was highest in autumn, followed by winter, summer and spring. Mite reproduction did not differ significantly between spring and summer. Loss of the queen significantly increased infestation in the bee brood.

Darbo tema: „Bičių šeimos kaip gamybos priemonės tyrimai“. Duomenys rinkti 2012-2013 metais iš 10 bitynų, kurie yra šiaurės rytų Aukštaitijos regione. Apklausti 5 bitininkai profesionalai ir 5 bitininkai mėgėjai. Raktiniai žodžiai: bitės, Varroa destructor erkės. Apie 64 proc. Lietuvos bitininkų savo bitynuose nekeičia bičių motinėlių, todėl sumažėja bičių produktyvumas. Taip pat, didžiausia bitynų problema yra Varroa destructor erkės, kadangi jos ne tik nualina bičių šeimą, bet yra viena iš esminių priežasčių, dėl bičių mirtingumo po žiemojimo. Darbo tikslas yra įvertinti veiksnius, labiausiai įtakojančius bičių populiacijos mažėjimui ir bičių produktyvumui. Taip pat išanalizuoti bitininkų kompetenciją bitininkystės srityje mėgėjų ir profesionaliuose bitynuose. Darbo uždaviniai: įvertinti bičių šeimų produktyvumą profesionaliuose bitynuose ir mėgėjų bitynuose: • Įvertinti Varroa destructor erkių paplitimą bičių šeimose; • Įvertinti Varroa destructor įtaką bičių šeimų produktyvumui; • Palyginti veislinių ir mišrūnių bičių produktyvumą; • Nustatyti, bičių šeimų, kuriose buvo keistos motinėlės produktyvumą ir atsparumą Varroa destructor erkėms; • Įvertinti medaus kokybinius rodiklius tirtuose bitynuose pagal medaus techninio reglamento reikalavimus; Atlikus analizę paaiškėjo, kad: • Produktyviausios bičių šeimos, kuriose bičių motinėlė keičiama kas du metus, ir nesirgo varoze. • Bičių šeimos sergančios varoze yra mažiau produktyvios. Iš sergančios šeimos profesionaliame... [toliau žr. visą tekstą] / Topic of the paper: “Research of a beehive as a mean of production”. Data collected from 10 apiaries in the region of northeast Upper Lithuania in the year 2012-2013. 5 professional and 5 amateur beekeepers were interviewed. Key words: bees, Varroa destructor mites. It is argued that about 64% of Lithuanian beekeepers apiaries does not change the queen bee, which reduces the productivity of the bees. Also, the biggest problem of the apiaries is Varroa destructor mites, which not only exhausts a beehive, but it is one of the most significant reasons for bee mortality after hibernation. Aim of the paper is to evaluate the most influential factors in declining of bee population and productivity. Also to analyze beekeepers competency in the fields of amateur an professional apiaries. Tasks of the paper: evaluate the productivity of bee colonies in professional and amateur apiaries. • Evaluate the spread of Varroa destructor mites in beehives; • Evaluate the influence of Varroa destructor to the beehive productivity; • Compare the productivity of pedigree and hybrid bees; • Identify beehives that productivity and immunity were affected by Varroa destructor mites; • Evaluate qualitative indicators of honey according to honey technical regulation requirements; The analysis shows that: • The most productive beehives are the ones where the queen bee is substituted every two year and never had varroasis; • Beehives that had varroasis are less productive. 35 kg or 27% less honey is... [to full text]

Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-03-13T13:17:05Z No. of bitstreams: 1 FranklinAS_DISSERT.pdf: 1406892 bytes, checksum: 31ccee360ab84a9af3e75803363344c4 (MD5) / Made available in DSpace on 2017-03-13T13:17:05Z (GMT). No. of bitstreams: 1 FranklinAS_DISSERT.pdf: 1406892 bytes, checksum: 31ccee360ab84a9af3e75803363344c4 (MD5) Previous issue date: 2016-02-27 / Africanized honey bees (Apis mellifera) from the region of the Semiarid Potiguar has two main diseases: varroatose, whose agent is the mite Varroa destructor and, the Nosemosis disease, recently introduced in the state, whose agent was previously identified in the area of our experimental apiaries as being the microsporide Nosema ceranae. The objectives of this study were to evaluate the effects of direct insolation and shading on the hives, in relation to the mite infestation rate in the adult bees and in the worker brood; on hygienic behavior and on the Nosemosis disease. The experiment was conducted in CETAPIS / UFERSA in the Mossoró-RN city. It were used 10 beehives installed under a metallic structure covered by dry leaves of coconut, it was built on the east-west direction, and with a capacity to absorbed about 90% of the direct insolation. Ten other beehives were installed under the direct effect of insolation, about 15 meters in relation to the former group. The results showed that during the dry season period the hives installed in the shade had an average infestation rate (%) in adult bees significantly lower (P <0.01) than in hives installed in the sun. Although the results show a smaller infestation trend on the bee brood of hives installed in the shade, no significant differences were observed (P = 0.253). Already hygienic behavior was very low, considering that the bees were Africanized bees and it were captured in the region during the swarming season. However, there was a significant negative correlation between the hygienic behavior and the mite infestation rate in adult bees. The nosemosis disease showed one prevalence of 100% in the experimental apiary, however, the average number of spores per bee can be considered very low, being significantly higher during the harvest period than in the off season period's, however, this results did not show significant differences between the hives receiving direct insolation and that ones under shade / As abelhas africanizadas (Apis mellifera) da região do Semiárido Potiguar apresentam duas doenças principais: A varroatose cujo agente é o ácaro Varroa destructor, e a nosemose, recentemente introduzida no estado, cujo agente foi identificado anteriormente na região dos apiários experimentais como sendo o microsporídio Nosema ceranae. Os objetivos desta pesquisa foram avaliar os efeitos diretos da insolação e do sombreamento sobre colmeias em relação à taxa de infestação do ácaro em abelhas adultas e nas crias; sobre o comportamento higiênico e sobre a doença nosemose. O experimento foi realizado no CETAPIS/UFERSA em Mossoró, RN, onde, utilizou-se 10 colmeias instaladas sob uma latada construída no sentido leste-oeste, coberta com folhas de coqueiro que absorvia cerca de 90% da insolação e, outras 10 sob efeito direto da insolação. As coletas foram feitas no período da safra (chuvoso), nos dias 30/01, 20/03, 09/4 e 10/05, e no período da entressafra (seca), nos dias 18/08, 23/09, 07/10 e 30/11. Os resultados mostraram que durante o período de entressafra as colmeias instaladas na sombra apresentaram uma taxa de infestação média (%) (6,54 ± 0,59) em abelhas adultas menor (P<0.01) do que nas colmeias instaladas no sol (9,71 ± 1,02). Embora os resultados tenham mostrado uma tendência de infestação menor nas crias em colmeias instaladas na sombra, em relação as instaladas no sol, não foram observadas diferenças significativas (P=0.253). Já o comportamento higiênico (%) foi muito baixo para as colmeias na sombra e no sol (57, 61 ± 6,44 e 57,33 ± 7,96) respectivamente. No entanto, observou-se uma correlação negativa significativa entre este comportamento e a taxa de infestação do ácaro em abelhas adultas. Quanto à nosemose, foram encontrados esporos em todas as colmeias tanto no sol quando na sombra, mas no entanto, o número médio de esporos por abelha pode ser considerado muito baixo, sendo significativamente maior no período de safra (200.000 ± 40. 869) do que na entressafra (31.250 ± 3.900), no entanto, não se obteve diferenças significativas entre as colmeias na sombra e no sol / 2017-03-13