Effect of primer pheromones and pollen diet on the food producing glands of worker honey bees (Apis mellifera L.)

Cooperative brood care is highly developed in the honey bee such that workers called nurses use their hypopharyngeal and mandibular glands to biosynthesize proteinaceous secretions that are progressively provisioned to larvae. The role that honey bee primer pheromones play in the functional physiology of food producing glands was examined. The combined and separate effects of queen mandibular pheromone (QMP) and brood pheromone (BP) on amount of protein extractable from hypopharyngeal and mandibular glands of workers reared for 12 days with and without pollen diets was measured. In rearing environments with a pollen diet, BP, and QMP + BP pheromone treatments significantly increased extractable protein from both glands. Bees reared with QMP + pollen had amounts of protein extractable from both glands that were not significantly different from control bees (no pheromones, no pollen). Pollen in the diet alone significantly increased amounts of protein extractable from glands versus control. In rearing environments without pollen, QMP + BP had a synergizing effect on amount of protein in both glands. The QMP + BP treatment was the only rearing environment without a pollen diet where protein amounts were significantly greater than the control. The synergizing effect of QMP + BP on extractable mandibular and hypopharyngeal gland protein suggests a highly derived role for the combined effect of these two primer pheromones on honey bee cooperative brood care. Mandibular gland area was significantly and positively correlated with extractable protein. Amounts of extractable protein from both glands declined significantly with age of workers in all treatments. However, treatment significantly affected rate of decline. The adaptive significance of gland protein amounts in response to pheromones and pollen diet are discussed.     

Dwindling pollen resources trigger the transition to broodless populations of long-lived honeybees each autumn

Abstract.  1. Each autumn in northern regions, honeybee colonies shift from populations of short-lived workers that actively rear brood to broodless populations of long-lived winter bees. To determine if dwindling pollen resources trigger this transition, the natural disappearance of external pollen resources was artificially accelerated or delayed and colonies were monitored for effects on the decline in brood-rearing activity and the development of populations of long-lived winter bees.
2. Delaying the disappearance of pollen resources postponed the decline in brood rearing in colonies. Colonies with an extended supply of pollen reared workers longer into October before brood rearing ended than control colonies or colonies for which pollen supply was cut short artificially in autumn.
3. Colonies with extended pollen supply produced more workers throughout autumn than colonies with less pollen, but the development of the population of long-lived winter bees was delayed until relatively later in autumn. Colonies produced similar numbers of winter bees, regardless of the timing of the disappearance of pollen resources.
4. Mean longevity of autumn-reared workers was inversely related to the amount of brood remaining to be reared in colonies when workers eclosed. Consequently, long-lived workers did not appear in colonies until brood rearing declined, which in turn was controlled by the availability of pollen.
5. Dwindling pollen resources provide a powerful cue that initiates the transition to populations of broodless winter bees because it directly affects the brood-rearing capacity of colonies and indirectly indicates deteriorating environmental conditions associated with the approach of winter.     

The relationship between comb age and performance of honey bee (Apis mellifera) colonies

A study on the relationship between the age of comb and the activity of the hybrid Carniolan honey bee colonies in collecting pollen activity, worker brood production, colony strength, and honey yield was conducted. In comparison to colonies with combs aged 4-years, colonies with combs aged 1, 2 and 3-years significantly exceeded in the number returning workers, number returning workers with pollen loads, rate of storing pollen, rate of worker brood production, and size of colony population. Colonies with combs aged 1, 2 and 3-years produced significantly more honey than colonies with combs aged 4-years (5.25, 4.90 and 4.65 kg/colony vs. 4.45 kg/colony, respectively). It can be concluded that the foraging rate, gathering and storing pollen, brood production, colony population size, and honey yield significantly depended on the age of combs. Beekeepers can replace old combs with new ones to increase brood and honey production.     

Exposure to clothianidin seed-treated canola has no long-term impact on honey bees

We conducted a long-term investigation to ascertain effects on honey bee, Apis mellifera L., colonies during and after exposure to flowering canola, Brassica napus variety Hyola 420, grown from clothianidin-treated seed. Colonies were placed in the middle of 1-ha clothianidin seed-treated or control canola fields for 3 wk during bloom, and thereafter they were moved to a fall apiary. There were four treated and four control fields, and four colonies per field, giving 32 colonies total. Bee mortality, worker longevity, and brood development were regularly assessed in each colony for 130 d from initial exposure to canola. Samples of honey, beeswax, pollen, and nectar were regularly collected for 130 d, and the samples were analyzed for clothianidin residues by using high-performance liquid chromatography with tandem mass spectrometry detection. Overall, no differences in bee mortality, worker longevity, or brood development occurred between control and treatment groups throughout the study. Weight gains of and honey yields from colonies in treated fields were not significantly different from those in control fields. Although clothianidin residues were detected in honey, nectar, and pollen from colonies in clothianidin-treated fields, maximum concentrations detected were 8- to 22-fold below the reported no observable adverse effects concentration. Clothianidin residues were not detected in any beeswax sample. Assessment of overwintered colonies in spring found no differences in those originally exposed to treated or control canola. The results show that honey bee colonies will, in the long-term, be unaffected by exposure to clothianidin seed-treated canola.     

The provision of supplementary food to hive bees

Sucrose syrup is less satisfactory than honey as a winter and spring food for bees: a mixture of approximately equal parts of honey and syrup is of almost the same value as honey alone.
Feeding confined to early autumn induced the strongest spring development of colonies; syrup feeding in the spring may retard colony development, and food supplied at this time is apparently wasted. Feeding with syrup and pollen is advantageous only when a colony is lacking in stores of carbohydrate and protein.
A total of four British Standard brood combs full of pollen provides sufficient protein for a colony on B.S. equipment from autumn until April: the best results were obtained by providing colonies on eleven B.S. combs, in early autumn, with 35-40 lb. of honey, or honey and concentrated sucrose syrup, and four brood combs full of pollen.     

Performance evaluation of indigenous and exotic honey bee (Apis mellifera L.) races in Assir region,southwestern Saudi Arabia

This study was conducted in the Assir region of southwestern Saudi Arabia to compare the activities of honeybee colonies of indigenous Apis mellifera jemenitica (AMJ) and imported Apis mellifera carnica (AMC) during the late summer and autumn of 2009 and 2010. The results showed that the workers of the two races exhibited relatively similar forage timings throughout the period of study (August–November). The highest numbers of foraged workers were recorded at 6:00 am, 10:00 am and 6:00 pm, while the lowest numbers were recorded at 8:00 am, 12:00 pm and 4:00 pm. Although foraging activity was negatively affected by decreased temperature, AMJ was more resistant to cold than AMC. In the first season, the smallest amount of worker brood rearing was recorded in August, and the highest amount of rearing occurred in November in both races. In the second season, the smallest amount of brood was observed in October, and the largest amount of brood was observed in November. Brood rearing and pollen collecting was significantly (P < 0.05) higher in AMJ compared with AMC, while AMC stored significantly (P < 0.05) more honey than AMJ during the tested periods. In AMJ colonies, a positive significant correlation was observed between the area of the sealed worker brood and stored pollen, while a negative but nonsignificant correlation was observed between the area of the sealed worker brood and surplus honey. In the AMC colonies, a positive significant correlation was observed between the area of the sealed brood and the stored pollen and surplus honey.     

The impact of caging the queens during the flow season on some biological activities of honeybee colonies

This study was achieved in a private apiary located in a banana farm in Sa El Hagar, Basioun, Gharbia, Egypt from August 15, 2019 to May 25, 2020, including the banana (Musa sp., Musaceae) flow season (August and September) and extend to Egyptian clover (Trifolium alexandrinum L., Fabaceae) flow season (May). The study aimed to evaluate the effect of confining the queen during the banana flow season on the brood rearing, honey yield, and activation of worker's ovaries. Also, we determined the negative impact of caging the queen during the banana flow season on the activity of the colony in brood rearing, storing pollen, and honey yield after releasing the queen on 5 October, extending to the next flow season in May. The obtained results showed that the honeybee colonies with the caged queen produced significantly more honey yield and less brood production than the free queen ones during the banana flow season. Also, the caging of the queen did not affect the colony strength after releasing the queen despite the partial development of the ovaries of some workers, but they did not lay eggs. In addition, releasing the queens suppressed the ovaries of the laying workers. It can be concluded that caging the queen during the banana flow season helps the colonies to produce more honey yield without effect on the colony strength after releasing the queen despite the ovaries development of few workers without egg-laying.     

Effects of brood pheromone (SuperBoost) on consumption of protein supplement and growth of honey bee (Hymenoptera: Apidae) colonies during fall in a northern temperate climate

Honey bee, Apis mellifera L. (Hymenoptera: Apidae), nutrition is vital for colony growth and maintenance of a robust immune system. Brood rearing in honey bee colonies is highly dependent on protein availability. Beekeepers in general provide protein supplement to colonies during periods of pollen dearth. Honey bee brood pheromone is a blend of methyl and ethyl fatty acid esters extractable from cuticle of honey bee larvae that communicates the presence of larvae in a colony. Honey bee brood pheromone has been shown to increase protein supplement consumption and growth of honey bee colonies in a subtropical winter climate. Here, we tested the hypothesis that synthetic brood pheromone (SuperBoost) has the potential to increase protein supplement consumption during fall in a temperate climate and thus increase colony growth. The experiments were conducted in two locations in Oregon during September and October 2009. In both the experiments, colonies receiving brood pheromone treatment consumed significantly higher protein supplement and had greater brood area and adult bees than controls. Results from this study suggest that synthetic brood pheromone may be used to stimulate honey bee colony growth by stimulating protein supplement consumption during fall in a northern temperate climate, when majority of the beekeepers feed protein supplement to their colonies.     

Brood Pheromone Modulation of Pollen Forager Turnaround Time in the Honey Bee (<Emphasis Type="Italic">Apis mellifera</Emphasis> L.)

Foraging for pollen is an important behavior of the honey bee because pollen is their sole source of protein. Through nurse bees, larvae are the principal consumers of pollen. Fatty acid esters extractable from the surface of larvae, called brood pheromone, release multiple colony-level and individual foraging behaviors increasing pollen intake. In this study pollen forager turnaround time was measured in observation hives supplemented with brood pheromone versus a blank control treatment. Treatment with brood pheromone significantly decreased pollen forager turnaround time in the hive between foraging bouts by approximately 72%. Concurrently, brood pheromone increased the ratio of pollen to non-pollen foragers entering colonies. Brood pheromone has been shown to release most of the mechanisms known to increase pollen intake by colonies acting as an important regulator of colony foraging decisions and growth.     

THE INFLUENCE OF STORED POLLEN AND OF COLONY SIZE ON THE BROOD REARING OF HONEYBEES

Four hundred and thirty records of the numbers of bees in honeybee colonies and of the amounts of brood and pollen present have been kept during various months of the years 1945-53, and the data have been used to calculate total and partial regression coefficients showing the influence of stored pollen and of colony size on brood rearing throughout the year.
It was found that pollen storage and colony size were correlated but that, even allowing for this, colony size and pollen both independently influenced brood rearing.
The annual distribution of the total regression coefficients of brood on pollen was somewhat similar to the brood curve itself, rising from a minimum in October and November to a maximum in midsummer, while the partial regression coefficients showed less clearly marked but similar features.
Both total and partial regression coefficients showing the influence of colony size on the amount of brood reared were also at a minimum in October and November, but reached their peaks in May.
The quantities of brood present in these colonies at Aberdeen, Scotland, followed a pattern similar to that given by Nolan for colonies near Washington, D.C.     

Treatment with synthetic brood pheromone (SuperBoost) enhances honey production and improves overwintering survival of package honey bee (Hymenoptera: Apidae) colonies

We evaluated a year-long treatment regime testing synthetic, 10-component, honey bee, Apis mellifera L. (Hymenoptera: Apidae), brood pheromone (SuperBoost; Contech Enterprises Inc., Delta, BC, Canada) on the productivity and vigor of package bee colonies in the lower Fraser Valley of British Columbia, Canada. Fifty-eight newlyestablished 1.3-kg (3-lb) colonies treated three times with SuperBoost at 5-wk intervals starting 30 April 2009 were compared with 52 untreated control colonies. Treated colonies produced 84.3% more honey than untreated control colonies. By 8 September 2009, SuperBoost-treated colonies had 35.4% more adults than untreated colonies. By 28 September, net survival of treated and control colonies was 72.4 and 67.3%, respectively. On 5 October, treated and control colonies were divided into two additional groups, making up four cohorts: SuperBoost-treated colonies treated again during fall and spring build-up feeding with pollen substitute diet (BeePro, Mann Lake Ltd., Hackensack, MN; TIT); controls that remained untreated throughout the year (CCC); colonies treated with SuperBoost in spring-summer 2009 but not treated thereafter (TCC); and original control colonies treated with SuperBoost during the fall and spring build-up feeding periods (CTT). There was no difference among cohorts in consumption of BeePro during fall feeding, but TTT colonies (including daughter colonies split off from parent colonies) consumed 50.8% more diet than CCC colonies during spring build-up feeding. By 21 April, the normalized percentages of the original number of colonies remaining (dead colonies partially offset by splits) were as follows: CCC, 31.4%; CTT, 43.8%; TCC, 53.59%; and TTT, 80.0%. The net benefit of placing 100 newly established package bee colonies on a year-long six-treatment regime with SuperBoost would be US$6,202 (US$62.02 per colony). We conclude that treatment with SuperBoost enhanced the productivity and survival of package bee colonies and hypothesize that similar results could be achieved with established colonies.     

The influence of social structure on brood survival and development in a socially polymorphic ant: insights from a cross‐fostering experiment

Animal societies vary in the number of breeders per group, which affects many socially and ecologically relevant traits. In several social insect species, including our study species Formica selysi, the presence of either one or multiple reproducing females per colony is generally associated with differences in a suite of traits such as the body size of individuals. However, the proximate mechanisms and ontogenetic processes generating such differences between social structures are poorly known. Here, we cross‐fostered eggs originating from single‐queen (= monogynous) or multiple‐queen (= polygynous) colonies into experimental groups of workers from each social structure to investigate whether differences in offspring survival, development time and body size are shaped by the genotype and/or prefoster maternal effects present in the eggs, or by the social origin of the rearing workers. Eggs produced by polygynous queens were more likely to survive to adulthood than eggs from monogynous queens, regardless of the social origin of the rearing workers. However, brood from monogynous queens grew faster than brood from polygynous queens. The social origin of the rearing workers influenced the probability of brood survival, with workers from monogynous colonies rearing more brood to adulthood than workers from polygynous colonies. The social origin of eggs or rearing workers had no significant effect on the head size of the resulting workers in our standardized laboratory conditions. Overall, the social backgrounds of the parents and of the rearing workers appear to shape distinct survival and developmental traits of ant brood.     

The relationship between population size,amount of brood,and individual foraging behaviour in the honey bee,Apis mellifera L.

This study experimentally examines the relationship between colony state and the behaviour of individual pollen and nectar foragers in the honey bee, Apis mellifera L. In the first experiment we test the prediction that individual pollen foragers from colonies with higher brood quantities should exhibit a greater work effort for pollen resources than individual pollen foragers from colonies with low brood quantities. Eight colonies were assigned into two treatment groups; HIGH brood colonies were manipulated to contain 9600±480 cm² brood area; LOW brood colonies were manipulated to contain 1600±80 cm² brood area. We measured colony brood levels over the course of the experiment and collected individual pollen loads from returning pollen foragers. We found that, while colonies remained significantly different in brood levels, individual pollen foragers from HIGH brood colonies collected larger loads than individuals from LOW brood colonies. In the second experiment we investigated the influence of colony size on the behaviour of individual nectar foragers. We assigned eight colonies to two treatment groups; LARGE colonies were manipulated to contain 35000±1700 adult workers with 3500±175 cm² brood area, and SMALL colonies were manipulated to contain 10000±500 adult workers with 1000±50 cm² brood area. We observed foraging trips of individually marked workers and found that individuals from LARGE colonies made longer foraging trips than those from SMALL colonies (LARGE: 1666.7±126.4 seconds, SMALL: 1210.8±157.6 seconds), and collected larter nectar loads (LARGE: 19.2±1.0 l, SMALL: 14.6±0.8 l). These results indicate that individual nectar foragers from LARGE colonies tend to work harder than individuals from SMALL colonies. Both experiments indicate that the values of nectar and pollen resources to a colony change depend on colony state, and that individual foragers modify their behaviour accordingly.     

Sterol utilization in honey bees fed a synthetic diet: Effects on brood rearing

The dietary sterols, cholesterol, campesterol, sitosterol, stigmasterol and 24-methylenecholesterol, were tested for their ability to support brood rearing in the honey bee, Apis mellifera L., by adding them singly to a chemically-defined worker bee diet. Diet supplemented with 24-methylenecholesterol supported the greatest survival of worker bees, but diet supplemented with either 24-methylenecholesterol or cholesterol supported the production of nearly equivalent amounts of sealed brood and more than any of the other three sterols tested. Diets containing stigmasterol, sitosterol, campesterol, or no supplement produced less sealed brood, in decreasing order.     

Survival of honeybees in cold climates: the critical timing of colony growth and reproduction

Abstract. 1. The adaptive significance of the timing of growth and reproduction by honeybee, Apis mellifera L., colonies in cold climates was studied by describing the seasonal patterns of food storage, brood rearing, and swarming, and then observing the consequences of experimentally perturbing the seasonal cycles of brood rearing and swarming.
2. Colonies consume large amounts of food over winter (20+ kg of honey), but have only a brief period (about 14 weeks) for food collection each year.
3. The honeybee's striking habits of starting brood rearing in midwinter and swarming in late spring evidently help colonies achieve maximum use of the short summer season. Colonies whose onset of-brood rearing was experimentally postponed until early spring showed greatly retarded colony growth and swarming. Other experiments demonstrated that late swarms starve more often during winter than do early swarms.
4. We conclude that the timings of colony growth and reproduction are essential elements in the honeybee's suite of adaptations for winter survival.     

Field and semifield evaluation of impacts of transgenic canola pollen on survival and development of worker honey bees

A 2-yr field trial (2001 and 2002) and 1-yr semifield trial (2002) were conducted to evaluate the effect of transgenic herbicide (glyphosate) -tolerant canola Brassica napus L. pollen on larval and adult honey bee, Apis mellifera L., workers. In the field trial, colonies of honey bees were moved to transgenic or nontransgenic canola fields (each at least 40 hectares) during bloom and then sampled for larval survival and adult recovery, pupal weight, and hemolymph protein concentrations. No differences in larval survival, adult recovery, and pupal weight were detected between colonies placed in nontransgenic canola fields and those in transgenic canola fields. Colonies placed in the transgenic canola fields in the 2002 field experiment showed significantly higher hemolymph protein in newly emerged bees compared with those placed in nontransgenic canola field; however, this difference was not detected in the 2001 field experiment. In the semifield trial, bee larvae were artificially fed with bee-collected transgenic and nontransgenic canola pollen and returned to their original colonies. Larval survival, pupal survival, pupal weight, and hemolymph protein concentration of newly emerged adults were measured. There were no significant differences in any of the parameters measured between larvae that were fed transgenic canola pollen and those fed nontransgenic corn pollen. Results from this study suggest that transgenic canola pollen does not have adverse effects on honey bee development and that the use of transgenic canola dose not pose any threat to honey bees.     

Diet does not affect intercolonial fighting in Leptothoracine ants

Summary An experiment examined the effects of diet on brood rearing in colonies ofLeptothorax ambiguus andL. longispinosus and on fighting between colonies of the two species. Colonies fedDrosophila and honey reared more pupae than colonies fed the Bhatkar and Whitcomb (1970) diet. However, diet had no effect on intercolonial fighting.     

不同人工代花粉对蜂群群势和生产性能的影响

早春将群势、蜂王年龄和质量基本一致的25群意大利蜜蜂Apis melliferaL.,随机分为5个处理,分别饲喂纯花粉和4种不同的人工代用花粉,观测它们对蜂群群势和生产性能的影响。结果表明,含有添加剂的各代用花粉组与纯花粉组的蜂群的蜂子数量差异均不显著,但均显著高于纯豆粕组(P<0.01);各组产蜜量随着纯花粉所占比例的减少而呈现递减的趋势,但饲喂含有60%花粉+40%豆粕+添加剂1组与纯花粉组没有明显的差异;含有添加剂的各代用花粉组的王台接受率均显著高于纯花粉组(P<0.01);饲喂含有添加剂的各代用花粉组与饲喂纯花粉组相比,王浆产量及蜂王浆中的10-HDA、水分、蛋白质的含量及酸度均没有差异。     

Drone and Worker Brood Microclimates Are Regulated Differentially in Honey Bees,Apis mellifera

Background

Honey bee (Apis mellifera) drones and workers show differences in morphology, physiology, and behavior. Because the functions of drones are more related to colony reproduction, and those of workers relate to both survival and reproduction, we hypothesize that the microclimate for worker brood is more precisely regulated than that of drone brood.

Methodology/Principal Findings

We assessed temperature and relative humidity (RH) inside honey bee colonies for both drone and worker brood throughout the three-stage development period, using digital HOBO^® Data Loggers. The major findings of this study are that 1) both drone and worker castes show the highest temperature for eggs, followed by larvae and then pupae; 2) temperature in drones are maintained at higher precision (smaller variance) in drone eggs and larvae, but at a lower precision in pupae than the corresponding stages of workers; 3) RH regulation showed higher variance in drone than workers across all brood stages; and 4) RH regulation seems largely due to regulation by workers, as the contribution from empty honey combs are much smaller compared to that from adult workers.

Conclusions/Significance

We conclude that honey bee colonies maintain both temperature and humidity actively; that the microclimate for sealed drone brood is less precisely regulated than worker brood; and that combs with honey contribute very little to the increase of RH in honey bee colonies. These findings increase our understanding of microclimate regulation in honey bees and may have implications for beekeeping practices.