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PubMed1994

[Effect of bee pollen on maternal nutrition and fetal growth].

Plant pollen collected by the honeybee is called bee pollen, which is a natural nutrient. We studied the effects of the bee pollen of Brassia campestres L. on maternal nutrition and fetal growth. Pregnant Sprague-Dawley rats at O-d were divided randomly into three groups. The control group (C) was fed with a diet. The other two groups (A) and (B) were fed with the diet plus bee pollen 20 g/kg.d-1 and 10 g/kg.d-1, respectively. All the dams in each group took a diet and drank water and libitm. Pollen-fed dams in both groups (A) and (B) had greater body weight and higher levels of haemoglobin, total protein, serum iron and albumin (P < 0.01, P < 0.05). Fetuses of pollen-fed dams had greater body weight (P < 0.01) and lower death rate (P < 0.005). No gross external, visceral and skeletal malformations were observed in the fetuses. These results suggested that bee pollen could improve maternal nutrition without affecting normal fetal development. It is a practical and effective nutrient during pregnancy.

Animal Nutritional Physiological Phenomena↗
PubMed1996

Influence of bee venom immunotherapy on degranulation and leukotriene generation in human blood basophils.

BACKGROUND: Rapid clinical tolerance can be induced over several hours by very fast bee venom immunotherapy (VIT) protocols. OBJECTIVE: To investigate the mechanisms underlying VIT we examined the changes of blood basophil responsiveness during VIT. METHODS: Seven bee venom allergic patients with a history of severe systemic reactions after a bee sting were investigated. A cumulative dose of 111.1 micrograms bee venom (BV) was administered sc over 3.5 h under intensive care conditions according to an ultra-rush protocol. The release of histamine and the formation of leukotrienes in response to BV, major BV allergen Phospholipase A2 (PLA), IgE receptor cross-linking with the use of monoclonal antibodies against IgE and IgE receptor, as well as IgE independent activation in response to C5a were determined in vitro before and after ultra-rush VIT. RESULTS: We demonstrated a decrease of total histamine in peripheral blood leucocytes just after VIT. Histamine release in response to all the stimuli used is not affected by ultra-rush VIT, if expressed as per cent release of total histamine. However, the absolute amount product released in response to stimulation was decreased, particularly with allergen (BV, PLA). We also found a significant reduction of LTC4 formation after VIT in samples stimulated with specific allergen (BV, PLA). CONCLUSION: Blood basophils are a target for VIT, which induces impaired release of both preformed and newly generated mediators. However, we believe the basic mechanisms of rapid clinical tolerance induced by ultra-rush VIT remain to be investigated.

Antibodies, Monoclonal↗
PubMed1996

Case reports and mini review of bee stings of the cornea.

Bee stings of the eye are not uncommon. Quite a few clinical case reports have documented the various ocular reactions to the venom of the bee stings, which may range from mild conjunctivitis to sudden loss of vision. This report presents 2 patients who suffered bee stings to the cornea and their different outcomes. The properties of bee venom as well as the treatment of various possible complications are also discussed.

Adult↗
PubMed1997

Increased specificity of diagnostic tests with recombinant major bee venom allergen phospholipase A2.

BACKGROUND: In diagnosis of type I allergy recombinant allergens have potential advantages over conventional allergenic extracts, both regarding specificity and reproducibility. OBJECTIVES: We therefore decided to study honey bee venom (BV) and its major allergen phospholipase A2 (PLA) in native and recombinant form for diagnosis of bee sting allergy. METHOD: We investigated 85 patients with a history of a recent systemic allergic bee sting reaction and positive intracutaneous skin test to BV, and 21 controls with no history of allergic bee sting reaction and negative skin test to BV. Intracutaneous skin tests and determination of specific IgE by ImmunoCAP(R) to BV, native PLA (nPLA) and recombinant PLA (rPLA) were done in all patients and controls. RESULTS: In skin testing 84 (99%) of the 85 patients reacted to nPLA and 81 (95%) to rPLA, while none of the 21 controls was positive with nPLA or rPLA. Specific serum IgE to BV could be detected in 82 of the patients (96%), to nPLA in 73 (86%) and to rPLA in 66 (78%). Four (19%) of the controls had a positive CAP to BV, one (4.8%) to nPLA and none to rPLA. Analysis of discordant results in CAP showed, that most patients with specific IgE to BV, but not to nPLA and rPLA, had positive skin tests to both PLA preparations and low levels of BV specific IgE. Patients with specific IgE to nPLA but not to rPLA were usually sensitized to minor allergens of BV which contaminated the commercial nPLA. CONCLUSIONS: PLA is the major allergen in BV. While diagnostic tests with BV are more sensitive, the specificity of tests with PLA, especially rPLA is clearly increased as compared with BV.

Allergens↗
PubMed1997

[Contamination of bee products and risk for human health: situation in France].

To meet the needs of a colony, bees collect honey, honey-dew, pollen and water from an environment exposed to various bacterial and chemical contaminants, which might be incorporated in products for human consumption. In addition to this environmental pollution, contamination of bee products may also occur during packing. In France, tests for various pollutants are performed more or less systematically, at the request of the Ministry of Agriculture, merchants or producers. Honey and royal jelly contain very little bacterial or chemical contamination, due to both the ability of colonies to eliminate pathogenic and non-pathogenic micro-organisms present in their environment, and to the physico-chemical properties of these products, as well as the role of bees in filtering chemical pollutants. To create the framework for European legislation on the testing of products, bacterial and chemical standards should be created and should be based on standardised techniques. The testing of imported bee products requires greater attention.

Animals↗
PubMedDate not supplied

Honeybee venom specific IgG subclass antibodies in Brazilian beekeepers and in patients allergic to bee stings.

Fifty-nine beekeepers who had been practicing apiculture for more than 2 years were selected in order to determine the distribution of bee venom specific IgG subclasses using ELISA. The assays were standardized into arbitrary units. For comparison, IgG subclasses were determined in eight individuals allergic to bee stings who did not receive specific treatment. No correlation was detected between beekeeping time and specific IgG1, IgG2 or IgG4 levels. There was a correlation between IgG2 levels and mean number of stings per month received by the beekeepers. Twenty-five percent of the beekeepers presented bee venom specific IgE class II or more in an ELISA assay. The IgG1 levels detected in beekeepers were similar to those detected in allergic individuals. IgG2 and IgG4 levels were significantly higher in beekeepers than in allergic individuals. IgG3 was not detected in any group studied. In conclusion, the maintenance of high levels of bee venom specific IgG2 and IgG4 represents a characteristic of beekeepers. These subclasses may be related to a modulatory effect of IgG on allergic reactions.

Adult↗
PubMed1999

Biogenic amines and division of labor in honey bee colonies: behaviorally related changes in the antennal lobes and age-related changes in the mushroom bodies.

Levels of the biogenic amines dopamine, serotonin, and octopamine were measured in different brain regions of adult worker honey bees as a function of age-related division of labor, using social manipulations to unlink age and behavioral state. In the antennal lobes, foragers had higher levels of all three amines than nurses, regardless of age. Differences were larger for octopamine than serotonin or dopamine. In the mushroom bodies, older bees had higher levels of all three amines than younger bees, regardless of behavioral state. These correlative results suggest that increases in octopamine in the antennal lobes may be particularly important in the control of age-related division of labor in honey bees.

Aging↗
PubMed2002

Bee-eaters ( Merops orientalis) respond to what a predator can see.

Two sets of experiments are reported that show that the small green bee-eater ( Merops orientalis, a small tropical bird) can appreciate what a predator can or cannot see. Bee-eaters avoid entering the nest in the presence of a potential nest predator. In the first set of experiments bee-eaters entered the nest more frequently when the predator was unable to see the nest from its position, as compared to an approximately equidistant position from which the nest could be seen. In the second set of experiments bee-eaters entered the nest more frequently when the predator was looking away from the nest. The angle of gaze from the nest was associated significantly positively with the probability of entering the nest whereas the angle from the bird was not. Birds showed considerable flexibility as well as individual variation in the possible methods of judging the predator's position and direction of gaze.

Animals↗
PubMed2000

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(A) (20.9-27.2 degrees C) head and abdomen were only about 3 degrees C and 2 degrees C on the average higher than the surroundings, respectively. In the lower range of T(A) (13.6-16.6 degrees C), however, the bees warmed their heads up to 29.2 degrees C (13 degrees C above T(A)) and the abdomen up to 23.3 degrees C (7.1 degrees C above T(A); mean values of the measuring periods).The head and abdomen were even provided independently of one another with heat from the thorax. At a higher T(A) only little heat came from the heated thorax into the abdomen, at a cooler T(A) (13.6-16.6 degrees C) more heat reached the abdomen. In all probability, at a higher T(A) only a small amount of haemolymph was pumped from the thorax into the abdomen; the most warm blood probably circulated in the head-thorax area. The average duration of stays at the pond decreased linearly from 110 to 42 s with rising T(A). Head and thorax showed great fluctuations of temperature. For example, the head was heated by 4.6 degrees C within 25 s, the thorax by 6.1 degrees C within 30 s.Foragers drinking sucrose solution are known to increase their thoracic temperature with rising concentration of the sucrose solution. The water foragers had thoracic temperatures similar to that of bees feeding on 0.5 molar sucrose solution. It is hypothesized that the foraging motivation of both groups was similar and therefore they regulated their thoraces at the same temperature level.

Journal Article↗
PubMed1997

Digestion of Pollen Components by Larvae of the Flower-Specialist Bee Chelostoma florisomne (Hymenoptera: Megachilidae).

Pollen digestion in larvae of the solitary bee Chelostoma florisomne (Megachilidae), a pollen-specialist (oligolectic) species on Ranunculus spp. (Ranunculaceae), was investigated using histological techniques. Serial sections from the anterior-, median-, and posterior-midgut/hindgut regions of the larval alimentary canal were selectively stained and examined for disappearance of lipids, proteins, and carbohydrates from ingested Ranunculus pollen grains. During digestion, pollen contents were observed to gradually extrude through the grain apertures. Most of the digestion of lipids and proteins occurred in the anterior- and median-midgut, whereas carbohydrates disappeared more slowly and mainly in the median- and posterior-midgut. In the hindgut, pollen comprised mainly empty exine shells, which were crushed and often broken, suggesting that some components of the wall are degraded during digestion, causing collapse of the outer, chemically resistant wall layer (exine). Lipids were completely digested, but small quantities of proteins and carbohydrates were often still present in grains in the posterior midgut/hindgut. The pollenkitt appeared to be completely absorbed, with none evident in the posterior midgut or in larval feces. The findings indicate that this oligolectic bee has the digestive equipment necessary to effectively remove and absorb the nutrients present in the pollen of its restricted food source. Comparison with similar studies in adult honey bees suggests that differing digestive abilities might be an underlying factor in pollen specialization in bees.

Journal Article↗
PubMed1997

Orientation-sensitive Neurons in the Brain of the Honey Bee (Apis mellifera).

Recent behavioural experiments have shown that bees are able to distinguish vertically presented patterns with orientation cues, although the locations of areas of black are randomized. To discriminate between two orientations, the bees must possess more than one orientation-sensitive neuron type. Therefore, the aim is to search for different types of orientation-sensitive cells of the honey bee, and measure their receptive field, velocity sensitivity and contrast sensitivity. Orientation-sensitive cells with two different types of orientation tuning-curves were recorded intracellularly in the mid-brain of the honey bee when the stimulus was a narrow bar (bar width = 5 degrees ). These cells are sensitive to bar movement within their large receptive field, which covers the visual field of one eye. They are quite distinct from the well-known directional motion detectors. The contrast sensitivity of the orientation-sensitive cells recorded in this study corresponds to results from behavioural experiments. The velocity-sensitivity curves of the orientation-sensitive cells differ from those of the direction-sensitive cells. Measurements of orientation sensitivity and contrast sensitivity when the stimulus is a wide bar (bar width = 10 degrees ), done in different eye regions, suggest that each orientation-sensitive cell receives visual signals from an array of orientational subunits within its receptive field. The correspondence between these physiological results and the results of recent behavioural experiments are discussed. Copyright 1997 Elsevier Science Ltd. All rights reserved

Journal Article↗
PubMed2003

Odor compound detection in male euglossine bees.

Male euglossine bees collect fragrances from various sources, which they store and use for as yet unknown purposes. They are attracted, often specifically, to single odor compounds and blends thereof. We used gas chromatography with electroantennographic detection (GC-EAD) and electroantennography (EAG) to investigate the response to 8 odor compounds by males of two euglossine species, Euglossa cybelia Moure and Eulaema polychroma (Mocsàry). In E. cybelia, we recorded EAD reactions in response to 1,8-cineole, methyl benzoate, benzyl actetate, methyl salicylate, eugenol, and methyl cinnamate. E. polychroma responded to the same compounds in EAG experiments, while (1s)(-)alpha-pinene and beta-pinene failed to trigger EAD or EAG responses in the bees. Blends of two compounds triggered larger responses than single compounds in EAG experiments with E. polychroma, however, when alpha-pinene was added, reactions decreased. In the light of existing data on the bees' behavior towards these odor compounds, our work indicates that both peripheral and central nervous processes influence the attraction of euglossine bees to odors.

Animals↗
PubMed2004

Multivariate discrimination among cryptic species of the mite genus Chaetodactylus (Acari: Chaetodactylidae) associated with bees of the genus Lithurgus (Hymenoptera: Megachilidae) in North America.

Twenty-seven morphological characters from 111 heteromorphic deutonymphs of the mite genus Chaetodactylus Rondani (Acari: Chaetodactylidae) were analyzed. The mites were collected from four species of bees of the genus Lithurgus Berthold (Hymenoptera: Megachilidae) in continental North America. Principal component and canonical variates analyses on Darroch and Mosimann shape and size-and-shape variables revealed the presence of three cryptic species. Chaetodactylus gibbosi sp. n. (Florida) is geographically isolated from C. lithurgi sp. n. distributed in Texas, New Mexico, Arizona, Colorado, and Idaho. Sympatric C. lithurgi and C. abditus sp. n. (USA: Arizona, Mexico: Socorro Is.) are seasonally isolated in Arizona. Chaetodactylus gibbosi is associated with a single bee species, Lithurgus gibbosus Smith in Florida. The host range of C. lithurgi includes bees flying predominantly in the spring: L. apicalis Cresson, L. littoralis Cockerell, and western L. gibbosus. Chaetodactylus abditus sp. n. is associated with L. planifrons Friese and L. echinocacti Cockerell, flying predominantly in the fall in Arizona. No distinct groups separated by geographic locality or size were detected in any species. A six-variable model developed by the canonical variates analysis and estimated using jackknife resampling and external validation (n = 100) is capable of classifying the three species with 100% accuracy. Factors that influenced speciation of cryptic species of Chaetodactylus associated with Lithurgus are discussed. Based on morphological and geographical data and data on mite associates, the western and eastern populations of the bee L. gibbosus are distinct. Therefore, the taxonomic status of L. gibbosus s. lat. should be reevaluated.

Animals↗
PubMed1982

The bee's map of the e-vector pattern in the sky.

It has long been known that bees can use the pattern of polarized light in the sky as a compass cue even if they can see only a small part of the whole pattern. How they solve this problem has remained enigmatic. Here we show that the bees rely on a generalized celestial map that is used invariably throughout the day. We reconstruct this map by analyzing the navigation errors made by bees to which single e-vectors are displayed. In addition, we demonstrate how the bee's celestial map can be derived from the e-vector patterns in the sky.

Journal Article↗
PubMed1994

Development of sun compensation by honeybees: how partially experienced bees estimate the sun's course.

Honeybees and some other insects, in learning the sun's course, behave as if they can estimate the sun's position at times of day when they have never seen it, but there are competing ideas about the computational mechanisms underlying this ability. In an approach to this problem, we provided incubator-reared bees with opportunities to fly and see the sun only during the late afternoon. Then, on a cloudy day, we allowed bees to fly for the first time during the morning and early afternoon, and we observed how they oriented their waggle dances to indicate their direction of flight relative to the sun's position. The clouds denied the bees a direct view of celestial orientation cues and thus forced them to estimate the sun's position on the basis of their experience on previous evenings. During the test days, experience-restricted bees behaved during the entire morning as if they expected the sun to be in an approximately stationary position about 180 degrees from the average solar azimuth that they had experienced on previous evenings; then from about local noon onward they used the evening azimuth. This pattern suggests that honeybees are innately informed of the general pattern of solar movement, such that they can generate an internal representation that incorporates spatial and temporal features of the sun's course that they have never directly seen.

Journal Article↗
PubMed1994

A comparative study of IgG subclass antibodies in patients allergic to wasp or bee venom.

IgG1 and IgG4 antivenom antibody responses were compared in groups of patients who had experienced systemic reactions to wasp (Vespula spp.) or bee stings. Pretreatment serum IgG4 antibody levels were low in both groups, but IgG1 antibodies were significantly raised in bee-allergic patients (P < 0.002), probably reflecting their greater exposure to stings than wasp-reactive patients. No direct or indirect relationships were found, in untreated bee or wasp patients, between IgG1, IgG4, or IgE antibody levels and the severity of a patient's last systemic reaction to a sting. After a 12-week course of venom immunotherapy (VIT), IgG1 antibodies increased significantly only in wasp-sensitive patients (P < 0.001), although both groups responded with marked increases in venom-specific IgG4 (P < 0.01). Wasp-allergic subjects who responded to VIT with high production of specific IgG4 showed the greatest increases (pre- to post-VIT) in IgE antibodies (P < 0.05). This group also demonstrated a direct correlation (P < 0.05) between post-VIT levels of IgE and IgG1 antibodies, a finding contrary to an IgE-immunoregulatory role for IgG1. High levels of venom-specific IgG1 alone, or in combination with IgG4, were not protective in three patients who suffered repeated adverse reactions to bee VIT, showing that absolute levels of IgG subclass antivenom antibodies are not reliably indicative of clinical responsiveness in individual patients.

Adult↗
PubMed2000

Flight activity and colony strength in the stingless bee Melipona bicolor bicolor (Apidae, Meliponinae).

Flight activity of Melipona bicolor bicolor, coming from Cunha (23o05'S, 44o55'W), Atlantic Forest, was studied in ten colonies, and in two periods: from July to September 1993 and from August to September 1995. The colonies were grouped in weak, medium and strong, according to the diameter of the combs, which can provide a good idea of the number of cells built. 855 observations were accomplished for 5 minutes, every half-hour, from 8 to 18 hours. The total number of bees that entered and left the hive and the number of bees that arrived with mud, pollen and resin, besides the number that went out with debris in that period were counted. It was also registered the temperature and the relative humidity of the air. The total external activity, as well as pollen collection, was maximum in the first hours of the morning, mainly in strong colonies. Weak colonies moved their maximum activity approximately to 12 hours. Pollen collection declined gradually, while mud and resin collection rose; removal of debris was greater in the beginning of the morning and in the end of the afternoon. Flight activity increased as relative humidity of the air rose, being optimum for strong colonies in the range between 80%-89%, and for the weakest colonies between 70%-79%. The minimum temperature observed for exit of the bees was 11oC, with optimum temperatures ranging between 17oC and 22oC. The results showed that the general state of the colony influences the different strategies of food collection and that these bees should be adapted to environments of high relative humidity as the Atlantic forest.

Journal Article↗
PubMed2001

Horizontal and vertical ectoparasite transmission of three species of Malophaga, and individual variation in european bee-eaters (Merops apiaster).

Dispersal of avian ectoparasites can occur through either vertical transmission from adult birds to their offspring in the nest or through horizontal transmission between adult birds or through phoresy. In this study, we investigated the importance of the 2 main transmission modes in the colonial European bee-eater and examined whether individual differences in ectoparasite intensity exist in relation to age, sex, and morphological features of the birds. The intensity of 3 chewing lice species was investigated. Almost all adult bee-eaters (98.3%, n = 176) were infested with 1 of the 3 ectoparasite species, whereas only 10.8% (n = 167) of all chicks were infested. Meropoecus meropis was the most frequent ectoparasite species on adult bee-eaters (prevalence 94.3%), whereas Meromenopon meropis was the most common species on chicks (prevalence 9.6%). Our results suggest that chewing lice are mainly horizontally transmitted among adult bee-eaters and mainly among pair members, whereas vertical transmission between parents and nestlings is less frequent. These conclusions were supported by a relation in ectoparasite intensity of pair members and a parasite removal experiment. Ectoparasite intensity was in general low in nestlings and did not correlate with ectoparasite intensity of their parents. Host age, sex, weight, and other morphological features did not explain variation in chewing lice infestation.

Age Factors↗