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Localization of deformed wing virus infection in queen and drone Apis mellifera L
Julie Fievet, Diana Tentcheva, Laurent Gauthier, Joachim de Miranda, Fran?ois Cousserans, Marc Colin, Max Bergoin
Virology Journal , 2006, DOI: 10.1186/1743-422x-3-16
Abstract: More than fifteen viruses have been described from honey bees (Apis mellifera L.) to date, most of which are 30 nm isometric particles containing a single positive strand RNA genome [1]. These viruses are widespread in honey bee colonies [2,3] with multiple virus infections in the same bee colony a common feature [3-7]. These infections are generally low level and symptomless [4,8], with occasional outbreaks producing clinical signs at individual bee or colony level [1]. Many infected bees remain asymptomatic and functional, although usually with a reduced life span [9]. This relatively benign scenario changed with the arrival of Varroa destructor which activates and transmits several of these viruses, resulting in greatly elevated incidence of these viruses [1,3,10]. Of these, deformed wing virus (DWV) appears to be closely associated with Varroa destructor infestation of bee colonies [11-14].Queen fecundity is a central element in colony performance for honey production that could be impaired by viral infections [6,15]. For instance, the undesired queen supersedure observed regularly by beekeepers may be related to viral infections. There are several reasons for untimely queen changing by workers in a colony, such as pathological impairment of its reproductive functions, lack of pheromone emission and lack of fully active spermatozoa in the spermatheca and decreasing sperm viability with the ageing of queens [16]. Very few investigations have been published regarding factors affecting the fertility of the queens and the drones [17].To study more precisely the etiology of DWV infection and to identify pathological effects on bee reproduction, we have attempted to localize DWV nucleic acid and viral particles in queen and drone organs by in situ hybridization and immunohistology. In parallel, tissue samples were analyzed by quantitative PCR to estimate the number of viral genome copies in the organs.DWV was detected by triplicate quantitative RT-PCR assays [14] in 6
Ovarian growth during larval development of queen and worker of Apis mellifera (Hymenoptera: Apidae): a morphometric and histological study
Reginato, R. D.;Cruz-Landim, C.;
Brazilian Journal of Biology , 2003, DOI: 10.1590/S1519-69842003000100016
Abstract: the present work reports the differences between the ovarian grow in queen and worker larvae of a. mellifera, from the start of differential feeding. the observations made of the growth rates in larvae of both castes showed that the queen and worker larvae have the same rates of cephalic capsule growth from one instar to another but the weight gain is greater in queens. in the same way, the draw areas of ovaries of queens increase more and continuously, while from the 5th instar on the ovaries of workers decrease in size. the decrease is due to a loss of ovariole numbers that starts early in the worker larvae and increases in the 4th-5th instar. the ovarian shape in queens and workers became different in the last larval instars.
Ovarian growth during larval development of queen and worker of Apis mellifera (Hymenoptera: Apidae): a morphometric and histological study  [cached]
Reginato R. D.,Cruz-Landim C.
Brazilian Journal of Biology , 2003,
Abstract: The present work reports the differences between the ovarian grow in queen and worker larvae of A. mellifera, from the start of differential feeding. The observations made of the growth rates in larvae of both castes showed that the queen and worker larvae have the same rates of cephalic capsule growth from one instar to another but the weight gain is greater in queens. In the same way, the draw areas of ovaries of queens increase more and continuously, while from the 5th instar on the ovaries of workers decrease in size. The decrease is due to a loss of ovariole numbers that starts early in the worker larvae and increases in the 4th-5th instar. The ovarian shape in queens and workers became different in the last larval instars.
Effects of queen ages on Varroa (Varroa destructor) infestation level in honey bee (Apis mellifera caucasica) colonies and colony performance  [cached]
Ethem Akyol,Halil Yeninar,Mustafa Karatepe,Bilge Karatepe
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2007.143
Abstract: This study was conducted to determine the effects of queen age on varroa population levels in hives and performance of honey bee (A. mellifera caucasica) colonies. Levels of varroa infestation and performances of the colonies which had 0, 1- and 2-year-old queens were compared in mild climate conditions. Varroa numbers on adults and drone brood, number of frames covered with bees and brood areas were determined every month between 10 May and 10 October 2004. Overall average (± S.E.) % infestation levels of varroa were found to be 5.96 ± 1.42, 11.58 ± 1.46 and 15.87 ± 1.39% on adult bees and 21.55 ± 1.43, 31.96 ± 1.44 and 37.55 ± 1.45% in drone brood cells for 0, 1- and 2-year-old queen colonies, respectively. The colonies which had 0, 1- and 2-year-old queens produced 2673.58 ± 39.69, 2711.75 ± 39.68, and 1815.08 ± 39.70 cm2 overall average (± S.E.) sealed brood and 10.35 ± 0.24, 10.43 ± 0.26 and 7.51 ± 0.21 numbers of frame adult bees, respectively. Honey harvested from 0, 1- and 2-year-old queen colonies averaged 21.60 ± 5.25, 22.20 ± 6.55, and 14.70 ± 2.50 kg/colony, respectively. The colonies headed by young queens had a lower level of varroa infestation, a greater brood area, longer worker bee population and greater honey yield in comparison to colonies headed by old queens.
SELECTION CRITERIA IN AN APIARY OF CARNIOLAN HONEY BEE (APIS MELLIFERA CARNICA) COLONIES FOR QUEEN REARING  [PDF]
Ale? Gregorc,Vesna Lokar
Journal of Central European Agriculture , 2011,
Abstract: Thirty six honey bee (Apis mellifera carnica) colonies were tested for gentleness, swarming behaviour, colony strength, racial characteristics, Cubital index (Ci), honey production, extension of capped brood, hygienic behaviour and the presence of Nosema spp. spores. The average value of Ci of all measures was 2.7 (±0.40). The average honey production was 9.5 kg (±6.6) and the area of capped brood was 7061 cm2 (±2813). Colonies expressed hygienic behaviour observed 24 hours after killing pupae twice in May and July at the level of 83.4% (±11.2). Each of twelve colonies uncapped and removed more than 90% of killed pupae, and of these, eight colonies cleaned more than 96% of killed pupae. The highest Nosema spp. spore load was found during September. We conclude that establishing the colony performance factors, with maximal level of 34 points, is a suitable tool for ranking and selection of colonies in each queen rearing apiary.
Effects of juvenile hormone and ecdysone on the timing of vitellogenin appearance in hemolymph of queen and worker pupae of Apis mellifera
Angel Roberto Barchuk,Marcia Maria Gentile Bitondi,Zilá Luz Paulino Sim?es
Journal of Insect Science , 2002,
Abstract: The caste-specific regulation of vitellogenin synthesis in the honeybee represents a problem with many yet unresolved details. We carried out experiments to determine when levels of vitellogenin are first detected in hemolymph of female castes of Apis mellifera, and whether juvenile hormone and ecdysteroids modulate this process. Vitellogenin levels were measured in hemolymph using immunological techniques. We show that in both castes the appearance of vitellogenin in the hemolymph occurs during the pupal period, but the timing was different in the queen and worker. Vitellogenin appears in queens during an early phase of cuticle pigmentation approximately 60h before eclosion, while in workers the appearance of vitellogenin is more delayed, initiating in the pharate adult stage, approximately 10h before eclosion. The timing of vitellogenin appearance in both castes coincides with a slight increase in endogenous levels of juvenile hormone that occurs at the end of pupal development. The correlation between these events was corroborated by topical application of juvenile hormone. Exogenous juvenile hormone advanced the timing of vitellogenin appearance in both castes, but caste-specific differences in timing were maintained. Injection of actinomycin D prevented the response to juvenile hormone. In contrast, queen and worker pupae that were treated with ecdysone showed a delay in the appearance of vitellogenin. These data suggest that queens and workers share a common control mechanism for the timing of vitellogenin synthesis, involving an increase in juvenile hormone titers in the presence of low levels of ecdysteroids.
Genomic analysis of post-mating changes in the honey bee queen (Apis mellifera)
Sarah D Kocher, Freddie-Jeanne Richard, David R Tarpy, Christina M Grozinger
BMC Genomics , 2008, DOI: 10.1186/1471-2164-9-232
Abstract: Differences in the behavior and physiology among groups correlated with the underlying variance observed in the top 50 predictive genes in the brains and the ovaries. These changes were correlated with either a behaviorally-associated pattern or a physiologically-associated pattern. Overall, these results suggest that the brains and the ovaries of queens are uncoupled or follow different timescales; the initiation of mating triggers immediate changes in the ovaries, while changes in the brain may require additional stimuli or take a longer time to complete. Comparison of our results to previous studies of post-mating changes in Drosophila melanogaster identified common biological processes affected by mating, including stress response and alternative-splicing pathways. Comparison with microarray data sets related to worker behavior revealed no obvious correlation between genes regulated by mating and genes regulated by behavior/physiology in workers.Studying the underlying molecular mechanisms of post-mating changes in honey bee queens will not only give us insight into how molecular mechanisms regulate physiological and behavioral changes, but they may also lead to important insights into the evolution of social behavior. Post-mating changes in gene regulation in the brains and ovaries of honey bee queens appear to be triggered by different stimuli and may occur on different timescales, potentially allowing changes in the brains and the ovaries to be uncoupled.Mating causes extensive short- and long-term modifications of physiology and behavior in females. In insects, mated females often become refractory to additional mating, their ovaries become activated, they form mature eggs, and they initiate egg-laying and/or foraging behavior [1-3]. However, there have been few studies that examine the molecular mechanisms underlying these post-mating changes, and all of these have been carried out using Drosophila melanogaster [1,3,4].The queen honey bee (Apis mellifera) p
A metallic impregnation technique adapted to study the honeybee Apis mellifera L. brain
Calábria, Luciana K;Teixeira, Renata R;Moraes, Viviane R A;Santos, Ana Alice D;Espindola, Foued S;
Neotropical Entomology , 2010, DOI: 10.1590/S1519-566X2010000500008
Abstract: in order to visualize the distribution pattern of the neuronal bodies and neurofibrils in the honeybee brain, we adapted a metallic impregnation technique first described for vertebrate nervous system by ramón y cajal. the honeybee brain constitution plays a key role in the development of learning and memory capacities. the general characteristics observed in the honeybee brain, stained by metallic impregnation, revealed its anatomical and morphological constitution in agreement with studies of other insect brains using different techniques. metallic impregnation evidenced the optic lobe neuropils, the ocelli fiber cells, the neuron extensions of the calyces, and the axon bundles that involve the antennal glomeruli, as well as the neuron extensions in the alpha lobe. we also observed that the antennal glomeruli were mainly formed by fibers. the optical lobes were impregnated distinctly in the monopolar neuron bodies and in the fibers. in the mushroom bodies, we observed the lip, collar and calyx basal areas. based on our results, the metallic impregnation technique is effective to visualize neuronal bodies and neurofibrils; moreover, is simpler and faster than other techniques, offering new insights for the investigation of the invertebrate nervous system.
The Effects of Pesticides on Queen Rearing and Virus Titers in Honey Bees (Apis mellifera L.)  [PDF]
Gloria DeGrandi-Hoffman,Yanping Chen,Roger Simonds
Insects , 2013, DOI: 10.3390/insects4010071
Abstract: The effects of sublethal pesticide exposure on queen emergence and virus titers were examined. Queen rearing colonies were fed pollen with chlorpyrifos (CPF) alone (pollen-1) and with CPF and the fungicide Pristine ? (pollen-2). Fewer queens emerged when larvae from open foraging ( i.e., outside) colonies were reared in colonies fed pollen-1 or 2 compared with when those larvae were reared in outside colonies. Larvae grafted from and reared in colonies fed pollen-2 had lower rates of queen emergence than pollen-1 or outside colonies. Deformed wing virus (DWV) and black queen cell virus were found in nurse bees from colonies fed pollen-1 or 2 and in outside colonies. The viruses also were detected in queen larvae. However, we did not detect virus in emerged queens grafted from and reared in outside colonies. In contrast, DWV was found in all emerged queens grafted from colonies fed pollen-1 or 2 either reared in outside hives or those fed pollen-1 or 2. The results suggest that sublethal exposure of CPF alone but especially when Pristine ? is added reduces queen emergence possibly due to compromised immunity in developing queens.
Effects of the Age of Grafted Larvae and the Effects of Supplemental Feeding on Some Morphological Characteristics of Iranian Queen Honey Bees (Apis mellifera meda Skorikov, 1929)
Ali Mahbobi , Mohammadbagher Farshineh-Adl , Jerzy Woyke , Saeed Abbasi
Journal of Apicultural Science , 2012, DOI: 10.2478/v10289-012-0010-1
Abstract: The research was conducted at the apiary of the Faculty of Agriculture, Zanjan University in Zanjan, Iran. Queens were reared in 24 Apis mellifera meda honey bee rearing colonies. The colonies were assigned to 4 grafting larvae age groups; 1 day old larvae, 2 day old larvae, and 3 day old larvae, and the last group reared emergency queen cells. The groups were divided into the 2 feeding groups: fed additionally and no fed. The effects of the age of the grafted larvae and the effects of supplemental feeding on 9 morphological characteristics of queens were measured. The results showed that the age of the larvae significantly affected the morphological characteristics of reared queens, and thus, their quality. Queens reared from 1 day old larvae were of the highest quality. These queens were significantly heavier (158.83 mg) and had significantly larger spermatheca (0.99 mm3) than queens reared from larvae 2 and 3 days old. Queens from emergency queen cells were of lower quality than queens reared from 1 day old larvae. However, queens from emergency queen cells were of higher quality than queens reared from 3 day old larvae. The supplemental feeding significantly increased most morphological characteristics of the reared queens. The different ages of the larvae did not significantly affect the wing length nor did supplemental feeding affect the wing length.
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