Publications

retrograde amnesia in honeybees (apis mellifera carnica).	after a single reward on a spectral color, freely flying honeybees show retrograde amnesia when an electroconvulsive shock, co2 narcosis, n2 narcosis, or cooling (to 1 degrees c) is applied after learning. retrograde amnesia is measurable with these four treatments up to 7 min after the reward. for none of the treatments was a consistent relationship found between the reaction tested and the time of testing after the treatment. prolonged application of the four treatments leads to a significant ...	1976	987070
sensitivity of ocellar interneurons of the honeybee to constant and temporally modulated light.	sinusoidally modulated and discrete light pulses, the parameters of which approximated natural light conditions, were used to determine the response characteristics of ocellar first-order interneurons of the worker honeybee (apis mellifera carnica). large ocellar interneurons which terminate within the brain (lb neurons) were recorded from intracellularly and were identified visually after dye injection. absolute sensitivity of lb neurons to light flashes ranges from 4 x 10(9) quanta/cm2s (q) fo ...	1989	2760607
[experimental studies of in vitro cultivation of the cells of kärtner honeybees (apis mellifera carnica pollmann, 1879)].	a synopsis about published methods and results on experiments to cultivate bee cells in vitro is given. experimental investigations were performed with haemocytes of larvae of the l-5 stage using many different media and methods for the preparation of primary tissue culture. monolayers could be prepared and a high rate of reproduction has been achieved, although subpassages could not be obtained. haemocytes could be kept alive up to 27 days by using bml-tc/7a medium according to gardiner and sto ...	1990	2220184
juvenile hormone titer in capped worker brood of apis mellifera and reproduction in the bee mite varroa jacobsoni.	juvenile hormone (jh) titers were recorded from fifth instar worker larvae of apis mellifera carnica, apis mellifera lamarckii, and africanized honeybees kept under temperate and tropical climatic conditions. no differences in hormone titer according to honeybee race or climatic conditions were determined. however, the rate of reproduction of the ectoparasitic mite, varroa jacobsoni, on larvae of the different honeybee races was highly variable. the possible role of honeybee jh in control of the ...	1990	2354762
transfer of paternal mitochondrial dna during fertilization of honeybee (apis mellifera l.) eggs.	strict maternal inheritance of mitochondrial (mt) dna is believed to be the rule in most eukaryotic organisms because of exclusion of paternal mitochondria from the egg cytoplasm during fertilization. in honeybees, polyspermic fertilization occurs, and many spermatozoa, including their mitochondria-rich flagellum, can completely penetrate the egg, thus allowing for a possibly high paternal leakage. in order to identify paternal mtdna in honeybee eggs, restriction fragment length polymorphisms (r ...	1993	8299176
relationship of the neutral sterols and ecdysteroids of the parasitic mite, varroa jacobsoni to those of the honey bee, apis mellifera.	the neutral sterols of the parasitic mite varroa jacobsoni were compared with apis mellifera carnica drone pupae. analysis by glc-mass spectrometry indicated mite sterols were reflective of the sterol composition of the drones; 24-methylenecholesterol was the major sterol in both species, with lesser amounts of sitosterol and isofucosterol. cholesterol accounted for less than 1% of the total sterols. ecdysteroid analyses indicated drones contained primarily makisterone a. in addition to makister ...	1997	12770416
mandibular gland volatiles and their ontogenetic patterns in queen honey bees, apis mellifera carnica.	extracts of mandibular glands taken from adult queens of the honey bee, apis mellifera carnica, were analysed by gas chromatography-mass spectroscopy. more than 100 compounds could be identified among which oxygenated fatty acids with six, eight, 10 and 12 carbon atoms are particularly interesting since they show structural relationships to the queen substance, (e)-9-oxo-2-decenoic acid. changes in the patterns of volatiles were followed up from emergence until the full dominant status of an egg ...	1997	12769892
glycogen in honeybee queens, workers and drones (apis mellifera carnica pollm.).	honey bees (apis mellifera carnica pollm.) have low glycogen reserves in summer. upon emergence drones have significantly larger amounts per unit weight when emerging, than workers; perhaps as adaption to the risk of not being fed as intensely as young workers. maximum content was 0.23mg for workers (28d), and 0.59mg for drones (after emergence). workers have relatively constant glycogen contents during their life, and very young drones have more glycogen than older ones. young queens are simila ...	1997	12769919
bees travel novel homeward routes by integrating separately acquired vector memories	the question of whether bees can take novel short cuts between familiar sites has been central to the discussion about the existence of cognitive maps in these insects. the failure of bees to show this capacity in the majority of previous studies may be a result of the training procedure, because extensive training to one feeding site may have eliminated or weakened memories for other sites that were previously trained. here we present a novel approach to this problem, by rewarding honey bees, a ...	1998	9480680
pharmacological dissociation between the reinforcing, sensitizing, and response-releasing functions of reward in honeybee classical conditioning.	reserpine depletes biogenic amines from their stores in the honeybee (apis mellifera carnica) brain and leads to impaired appetitive conditioning using sucrose as a reinforcer. compensatory injection of octopamine or dopamine directly into the brain restores these behavioral losses. dopamine rescues the slowing-down effect on motor patterns, but not sensitization or conditioning. octopamine leaves the motor patterns as well as sensitization unchanged but rescues conditioning. specifically, octop ...	1999	10495082
hypertrehalosaemic peptides in the honeybee (apis mellifera): purification, identification and function.	the corpora cardiaca (cc) of the italian race (including also the africanised variety) of the honeybee (apis mellifera ligustica) contain approximately 3 pmol of a hypertrehalosaemic peptide. this peptide is identical in structure to the adipokinetic hormone (akh) found in manduca sexta, mas-akh. the cc of the dark european race of the honeybee (apis mellifera carnica) contain no detectable mas-akh or any other adipokinetic/hypertrehalosaemic peptide. this is the first report of the occurrence o ...	1999	12770350
importance of proline and other amino acids during honeybee flight--apis mellifera carnica pollmann).	the levels of proline and other amino acids in the haemolymph and other body parts of honeybee foragers were investigated by hplc analysis. the concentrations of proline in the blood of glucose-fed or -injected bees finishing their exhaustive tethered flights on a roundabout were significantly reduced compared to bees that were fed and rested for one hour. this indicates some utilization of proline during flight metabolism. the levels of essential amino acids and of the sum of all amino acids ex ...	2000	10817408
thermoregulation of water collecting honey bees (apis mellifera).	honey bees (apis mellifera carnica, apidae, hymenoptera) visited a pond in order to collect water. during their stays at the pond the body surface temperature of water foragers was measured using contactless thermography. irrespective of the ambient temperature (t(a)) which ranged from 13.6 to 27.2 degrees c, the water carriers reached thoracic temperatures of 36-38.8 degrees c (mean values of the measuring periods). the maximum thoracic value of an individual bee was 44.5 degrees c. at higher t ...	2000	10818246
risk-indifferent foraging behaviour in honeybees.	we studied the influence of variance in reward volume on choice behaviour of honeybees, apis mellifera carnica, by training bees to collect sucrose solution from four newly developed artificial feeders. the feeders were electromechanical devices, each controlled by a microprocessor, which monitored the experiments, controlled reward delivery and stored the data. the parameters that varied between the feeders were the amount and variance of reward. the four feeders were arranged in two pairs, wit ...	2000	11082236
thermoregulation of dancing bees: thoracic temperature of pollen and nectar foragers in relation to profitability of foraging and colony need.	the thorax surface temperature of dancing honeybees (apis mellifera carnica) recruiting nestmates to natural sources of nectar and pollen around graz (austria) was measured by real-time infrared thermography without touching them or disturbing social interactions. thorax temperature during dancing was quite variable (31.4-43 degrees c). in the course of a foraging season it varied considerably and was always lower than in bees foraging from a highly profitable food source (2 molar sucrose 120 m ...	2001	11166303
free fatty acids digested from pollen and triolein in the honeybee (apis mellifera carnica pollmann) midgut.	honey bees satisfy their lipid requirement by consuming pollen. the free fatty acid content of the midgut was used to quantify fat digestion. midguts extracted from younger workers of known ages and from foragers were divided into three components: endoperitrophic region (peritrophic membrane with gut contents), extraperitrophic region and intestinal wall. both the total amount of pollen and the amount of free fatty acids in the endoperitrophic region and in the intestinal wall depend on the bee ...	2001	11409628
enantioselectivity of odor perception in honeybees (apis mellifera carnica).	the authors tested the ability of 60 free-flying honeybees (apis mellifera carnica) to discriminate a conditioning odor from an array of 26 simultaneously presented substances. the stimuli included 10 pairs of enantiomers and 6 essential oils. the bees (a) significantly distinguished between 98% of the 540 odor pairs tested, thus showing an excellent overall discrimination performance, and (b) were able to discriminate between the optical isomers of limonene, alpha-pinene, beta-citronellol, ment ...	2001	11439452
haemolymph sugar levels in foraging honeybees (apis mellifera carnica): dependence on metabolic rate and in vivo measurement of maximal rates of trehalose synthesis.	previous investigations of haemolymph sugar levels in honeybees have reported very different results, probably because different experimental conditions affected the activity levels of the animals. the present study investigated the dependence of haemolymph sugar levels in foraging honeybees on metabolic rate and whether the haemolymph sugar level is regulated. free-flying foraging bees were trained to collect controlled amounts of sucrose solution of different concentrations (15%, 30% or 50% su ...	2001	11533121
the possible role of varroa destructor in the spreading of american foulbrood among apiaries.	the aim of this investigation was to establish whether varroa destructor can play a role in the transmission of paenibacillus larvae larvae spores from infected to healthy bee colonies. mites, collected from an apis mellifera carnica colony heavily infected with american foulbrood and treated with apistan, were suspended in distilled water and treated in three different ways:homogenizing, shaking and stirring, or sonication. the resulting fluid samples were transferred onto selective agar medium ...	2002	12797406
the control of the proventriculus in the honeybee (apis mellifera carnica l.) ii. feedback mechanisms.	the mechanisms underlying the control of solution transport rates through the proventriculus in foraging honeybees were investigated in individuals trained to collect defined amounts of sugar solutions. following feeding, bees were injected either with metabolisable (glucose, fructose, trehalose), or non-metabolisable (sorbose) sugars, in order to distinguish between haemolymph osmolarity and haemolymph sugar levels as factors controlling the solution transport rates through the proventriculus. ...	2002	12770062
the control of the proventriculus in the honeybee (apis mellifera carnica l.) i. a dynamic process influenced by food quality and quantity?	the control of crop emptying in foraging honeybees was investigated in individuals trained to collect defined amounts of sugar solutions. following feeding, they were dissected after fixed periods of time in order to measure crop content and haemolymph sugar titers. between feeding and dissection, the metabolic rate of every investigated forager was measured using open-flow respirometry, so as to assess the effects of both food quality (concentration, molarity and viscosity of the fed sugar solu ...	2002	12770075
oxygen consumption and body temperature of active and resting honeybees.	we measured the energy turnover (oxygen consumption) of honeybees (apis mellifera carnica), which were free to move within warburg vessels. oxygen consumption of active bees varied widely depending on ambient temperature and level of activity, but did not differ between foragers (>18 d) and middle-aged hive bees (7-10 d). in highly active bees, which were in an endothermic state ready for flight, it decreased almost linearly, from a maximum of 131.4 microl o(2) min(-1) at 15 degrees c ambient te ...	2003	16256690
raman spectroscopic study of spatial distribution of propolis in comb of apis mellifera carnica (pollm.).	micro-raman spectroscopy and raman mapping are applied to investigate the spatial distribution and chemical composition of wax and propolis in the comb of apis mellifera carnica (pollm). a thick layer of propolis at the rim of some cells is identified by raman spectroscopy. raman mapping is applied to resolve the distribution of propolis and wax on a micron scale. both components are connected at the rim of the cell with a mixture of wax and propolis. a layer of almost pure propolis is found on ...	2003	12833475
effects of the beehive type and queen-bee descent on the development of the bee-diseases at apiaries.	an increased occurrence of disease at various members of the honeybee brood (queen-bee, workers, and drones) settled in the beehive, become evident recently. it is already known that various factors, primary ecological, determine disease development. the aim of the study was to discover which diseases at apiaries corresponds to similar ecological conditions at different beehive types. effects of the following factors were studied: beehive type and building material, type and descent of the queen ...	2003	12974169
a comparison of the dance language in apis mellifera carnica and apis florea reveals striking similarities.	honeybees have a dance language by which successful foragers inform nestmates about attractive food patches. the classical concept of dialects in the dance language of honeybees points to two differences in the dances by different species and races, firstly in the flight distance at which the dancers start performing waggle dances instead of round dances, and secondly in the circuit duration of the waggle dance performed for a given flight distance. however, recent findings have indicated that t ...	2004	14625781
respiration of individual honeybee larvae in relation to age and ambient temperature.	the co(2) production of individual larvae of apis mellifera carnica, which were incubated within their cells at a natural air humidity of 60-80%, was determined by an open-flow gas analyzer in relation to larval age and ambient temperature. in larvae incubated at 34 degrees c the amount of co(2) produced appeared to fall only moderately from 3.89 +/- 1.57 microl mg(-1) h(-1) in 0.5-day-old larvae to 2.98 +/- 0.57 microl mg(-1) h(-1) in 3.5-day-old larvae. the decline was steeper up to an age of ...	2004	15278398
influence of the beehive type on the quality of honey.	agricultural producers apply numerous technological procedures, and enlarging efforts to produce the high-quality products. this initiative is present in the beekeeping, too. the quality of the honey produced by the honey bee colonies depends of various factors, but prevailing are the ecological conditions and the floristic composition of the honeyfull plants. the aim of our research was to discover the influence of the beehive type on the quality of honey, which is produced at apiaries under th ...	2004	15636106
chemical composition and antibacterial activity of propolis collected by three different races of honeybees in the same region.	the chemical analysis and antibacterial activity of three types of propolis collected three different races of apis mellifera bee in the same apiary were investigated. propolis samples were investigated by gc/ms, 48 compounds were identified 32 being new for propolis. the compounds identified indicated that the main plant sources of propolis were populus alba, populus tremuloides and salix alba. the antimicrobial activity against staphylococcus aureus, escherichia coli, pseudomonas aeruginosa an ...	2005	15848022
effect of honeybee broods (queen-bee different lineage) moving on disease development at various beehive types and allergy reaction cause in humans.	the change of the location of the beehives on the diverse honeyfull pastures is the usual apiarists activity in the republic of croatia. the main reasons are the climatic and vegetation diversity, and richness of the floral composition, with numerous bee forage plants. our study aimed to detect consequences of honeybee broods (queen-bee of different lineage) moving, from one habitat to another at various type of beehives. the alberti-znidersic (az), langstroth-root (lr) and dadant-blatt (db) bee ...	2005	16117345
analysis of peptides in the brain and corpora cardiaca-corpora allata of the honey bee, apis mellifera using maldi-tof mass spectrometry.	the neuropeptide profiles and diversity of the brain and retrocerebral organs (corpora cardiaca-corpora allata; cc-ca) of adult workers of the honey bee apis mellifera carnica (dark european strain) were investigated using a combination of hplc and matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) with post-source decay (psd) and collision-induced dissociation (cid) fragmentation. using evidence from genomic sources, including blast searches of the honey ...	2006	16309791
reduced ability of ethanol drinkers for social communication in honeybees (apis mellifera carnica poll.).	foraging behavior was evaluated in honeybees trained to fly to a feeder containing sucrose only, 1% ethanol, 5% ethanol, or 10% ethanol. the results indicated that exposure to ethanol disrupted several types of honeybee social behavior within the hive. consumption of ethanol at the feeding site reduced waggle dance activity in foraging bees and increased occurrence of tremble dance, food exchange, and self-cleaning behavior. these ethanol-induced changes in behavior may reflect effects on the ce ...	2006	16905444
influence of carbon dioxide on nosema apis infection of honeybees (apis mellifera).	young workers of the honeybee apis mellifera carnica were individually inoculated with nosema apis spores subjected to carbon dioxide (co(2)) treatment. the spores were kept in a co(2) atmosphere for 30, 35 and 40 h. the course of the infection was evaluated on the basis of the survival rate of bee workers and the number of n. apis spores in their digestive tracts. co(2) treatment of n. apis spores resulted in faster proliferation of the parasite as well as higher mortality among workers infecte ...	2007	17386934
caps and gaps: a computer model for studies on brood incubation strategies in honeybees (apis mellifera carnica).	in addition to heat production on the comb surface, honeybee workers frequently visit open cells ("gaps") that are scattered throughout the sealed brood area, and enter them to incubate adjacent brood cells. we examined the efficiency of this heating strategy under different environmental conditions and for gap proportions from 0 to 50%. for gap proportions from 4 to 10%, which are common to healthy colonies, we find a significant reduction in the incubation time per brood cell to maintain the c ...	2007	17443307
molecular cloning and characterization of bombyx mori creb gene.	the camp response element binding protein (creb), as one of the best characterized stimulus-induced transcription factors, plays critical roles in activating transcription of target genes in response to a variety of environmental stimuli. to characterize this important molecule in the silkworm, bombyx mori, we cloned a full-length cdna of creb gene from b. mori brains by using race-pcr. the sequence of b. mori creb (named bmcreb1) gene contains a 88 bp 5' utr, a 783 bp open reading frame (orf) e ...	2009	19194985
residues of pesticides in honeybee (apis mellifera carnica) bee bread and in pollen loads from treated apple orchards.	honey bee (apis mellifera carnica) colonies were placed in two apple orchards treated with the insecticides diazinon and thiacloprid and the fungicide difenoconazole in accordance with a protection treatment plan in the spring of 2007. pollen and bee bread were collected from combs inside the hives. the residue of diazinon in pollen loads 10 days after orchard treatment was 0.09 mg/kg, and the same amount of residue was found in bee bread 16 days after treatment. in pollen loads 6 days after app ...	2009	19434347
sequential hygienic behavior in carniolan honey bees (apis mellifera carnica).	we examined the sequence, order or steps of hygienic behavior (hb) from pin-killed pupae until the removal of them by the bees. we conducted our study with four colonies of apis mellifera carnica in germany and made four repetitions. the pin-killing method was used for evaluation of the hb of bees. the data were collected every 2 h after perforation, totaling 13 observations. additionally, for one hygienic colony and another non-hygienic colony, individual analyses of each dead pupa were made at ...	2009	19554764
africanized honey bees more efficiently convert protein diets into hemolymph protein than do carniolan bees (apis mellifera carnica).	the superiority of africanized over european honey bees in tropical and subtropical regions of the new world is both well documented and poorly understood. as part of an effort to try to understand the process by which the displacement of european bees occurred, we examined the ability of these two types of bees and of hybrids between the two to convert natural and artificial diets into usable protein. newly emerged bees from colonies of tropically adapted africanized and temperate-origin carnio ...	2009	19876865
biogeographic study of the honey bee (apis mellifera l.) from serbia, bosnia and herzegovina and republic of macedonia based on mitochondrial dna analyses.	in this work, apis mellifera carnica and a. m. macedonica honey bees from serbia, bosnia and herzegovina and republic of macedonia were analysed using molecular techniques in order to improve our knowledge about biogeography of a. mellifera on the balkan peninsula. this is the first time that the indigenous honey bees from bosnia and herzegovina and republic of macedonia have been analyzed using a molecular approach. sampling was carried out from 560 stationary apiaries where bees were kept in t ...	2010	20583605
thermoregulation of water foraging honeybees--balancing of endothermic activity with radiative heat gain and functional requirements.	foraging honeybees are subjected to considerable variations of microclimatic conditions challenging their thermoregulatory ability. solar heat is a gain in the cold but may be a burden in the heat. we investigated the balancing of endothermic activity with radiative heat gain and physiological functions of water foraging apis mellifera carnica honeybees in the whole range of ambient temperatures (t(a)) and solar radiation they are likely to be exposed in their natural environment in middle europ ...	2010	20705071
the behavior and social communication of honey bees (apis mellifera carnica poll.) under the influence of alcohol.	in this study, the effects of ethanol on honey bee social communication and behavior within the hive were studied to further investigate the usefulness of honey bees as an ethanol-abuse model. control (1.5 m sucrose) and experimental (1.5 m sucrose, 2.5% w/v ethanol) solutions were directly administered to individual forager bees via proboscis contact with glass capillary tubes. the duration, frequency, and proportion of time spent performing social and nonsocial behaviors were the dependent var ...	2010	20712158
sensory evaluation of pralines containing different honey products.	in this study, pralines manufactured by hand were evaluated sensorially. these pralines were obtained from dark chocolate containing 60% cocoa components, filled with apis mellifera carnica poll drone larvae, blossom honey and a blossom honey/pollen mixture from the protected region of stara planina-eastern serbia (a specific botanical region). the objectives of this study were investigations related to the use of sensory analysis for quality assessment of new functional products with potential ...	2010	22163633
thermoregulation of foraging honeybees on flowering plants: seasonal variability and influence of radiative heat gain.	1. during nectar and pollen foraging in a temperate climate, honeybees are exposed to a broad range of ambient temperatures, challenging their thermoregulatory ability. the body temperature that the bees exhibit results from endothermic heat production, exogenous heat gain from solar radiation, and heat loss. in addition to profitability of foraging, season was suggested to have a considerable influence on thermoregulation. to assess the relative importance of these factors, the thermoregulatory ...	2011	22419834
development of a 44k snp assay focussing on the analysis of a varroa-specific defence behaviour in honey bees (apis mellifera carnica).	honey bees are exposed to a number of damaging pathogens and parasites. the most destructive among them, affecting mainly the brood, is varroa destructor. a promising approach to prevent its spread is to breed for varroa-tolerant honey bees. a trait that has been shown to provide significant resistance against the varroa mite is hygienic behaviour, a behavioural response of honey bee workers to brood diseases in general. this study reports the development of a 44k snp assay, specifically designe ...	2011	22212375
analysis of the waggle dance motion of honeybees for the design of a biomimetic honeybee robot.	the honeybee dance "language" is one of the most popular examples of information transfer in the animal world. today, more than 60 years after its discovery it still remains unknown how follower bees decode the information contained in the dance. in order to build a robotic honeybee that allows a deeper investigation of the communication process we have recorded hundreds of videos of waggle dances. in this paper we analyze the statistics of visually captured high-precision dance trajectories of ...	2011	21857906