Bee Bread Production—A New Source of Income for Beekeeping Farms?

Bee bread, i.e., floral pollen collected and partially processed by honey bees, is a source of many compounds beneficial for the human health. So far, the level of bee bread production in apiaries has been low due to many factors. However, development of such production may be significant as a new source of income for beekeepers. In spring 2015 a three-year study was started to determine bee bread production scale in honey bee colonies and assess the economic efficiency of such production. The experiment included 28 honey bee colonies each year; the colonies were divided into four groups. Each group tested different brood nest configuration or frames’ placement against the hive entrance for the amount of harvested bee bread. All the costs, including labor input, were related to the process of bee bread production. Depending on the group, it was possible to harvest from 0.51 to 1.23 kg of bee bread from one colony. The average production amounted to 0.7 kg, and the entire apiary gave 20 kg of bee bread annually. Annual costs connected to bee bread production amounted to 679.5 EUR, while the estimated income from sales amounted to 1110 EUR. Thus, the profit was 430.5 EUR, i.e., 21.5 EUR per 1 kg of harvested bee bread. The highest costs were connected to labor and they may potentially comprise a factor limiting the development of bee bread production in apiaries.

Coping with the cold and fighting the heat: thermal homeostasis of a superorganism, the honeybee colony

The worldwide distribution of honeybees and their fast propagation to new areas rests on their ability to keep up optimal ‘tropical conditions’ in their brood nest both in the cold and in the heat. Honeybee colonies behave like ‘superorganisms’ where individuals work together to promote reproduction of the colony. Social cooperation has developed strongly in thermal homeostasis, which guarantees a fast and constant development of the brood. We here report on the cooperation of individuals in reaction to environmental variation to achieve thermal constancy of 34–36 °C. The measurement of body temperature together with bee density and in-hive microclimate showed that behaviours for hive heating or cooling are strongly interlaced and differ in their start values. When environmental temperature changes, heat production is adjusted both by regulation of bee density due to migration activity and by the degree of endothermy. Overheating of the brood is prevented by cooling with water droplets and increased fanning, which start already at moderate temperatures where heat production and bee density are still at an increased level. This interlaced change and onset of different thermoregulatory behaviours guarantees a graded adaptation of individual behaviour to stabilise the temperature of the brood.

Social Fever or General Immune Response? Revisiting an Example of Social Immunity in Honey Bees

Honey bees use several strategies to protect themselves and the colony from parasites and pathogens. In addition to individual immunity, social immunity involves the cumulative effort of some individuals to limit the spread of parasites and pathogens to uninfected nestmates. Examples of social immunity in honey bees that have received attention include hygienic behavior, or the removal of diseased brood, and the collection and deposition of antimicrobial resins (propolis) on interior nest surfaces. Advances in our understanding of another form of social immunity, social fever, are lacking. Honey bees were shown to raise the temperature of the nest in response to temperature-sensitive brood pathogen, Ascosphaera apis. The increase in nest temperature (−0.6 °C) is thought to limit the spread of A. apis infection to uninfected immatures. We established observation hives and monitored the temperature of the brood nest for 40 days. This observation period was broken into five distinct segments, corresponding to sucrose solution feedings—Pre-Feed, Feed I, Challenge, Feed II, and Post-Feed. Ascosphaera apis was administered to colonies as a 1% solution of ground sporulating chalkbrood mummies in 50% v/v sucrose solution, during the Challenge period. Like previous reports, we observed a modest increase in brood nest temperature during the Challenge period. However, all hives presented signs of chalkbrood disease, suggesting that elevation of the nest temperature was not sufficient to stop the spread of infection among immatures. We also began to explore the molecular mechanisms of temperature increase by exposing adult bees in cages to A. apis, without the presence of immatures. Compared to adult workers who were given sucrose solution only, workers exposed to A. apis showed increased expression of the antimicrobial peptides abaecin (p = 0.07) and hymenoptaecin (p = 0.04), but expression of the heat shock response protein Hsp 70Ab-like (p = 0.76) and the nutritional marker vitellogenin (p = 0.72) were unaffected. These results indicate that adult honey bee workers exposed to a brood pathogen elevate the temperature of the brood nest and initiate an immune response, but the effect of this fever on preventing disease requires further study.

Regulation of Microclimatic Conditions inside Native Beehives and Its Relationship with Climate in Southern Spain

In this study, the Wbee Sensor System was used to record data from 10 Iberian beehives for two years in southern Spain. These data were used to identify potential conditioning climatic factors of the internal regulatory behavior of the hive and its weight. Categorical principal components analysis (CATPCA) was used to determine the minimum number of those factors able to capture the maximum percentage of variability in the data recorded. Then, categorical regression (CATREG) was used to select the factors that were linearly related to hive internal humidity, temperature and weight to issue predictive regression equations in Iberian bees. Average relative humidity values of 51.7% ± 10.4 and 54.2% ± 11.7 were reported for humidity in the brood nest and in the food area, while average temperatures were 34.3 °C ± 1.5 in the brood nest and 29.9 °C ± 5.8 in the food area. Average beehive weight was 38.2 kg ± 13.6. Some of our data, especially those related to humidity, contrast with previously published results for other studies about bees from Central and northern Europe. Conclusively, certain combinations of climatic factors may condition within hive humidity, temperature and hive weight. Southern Iberian honeybees’ brood nest humidity regulatory capacity could be lower than brood nest thermoregulatory capacity, maintaining values close to 34 °C, even in dry conditions.

Nectar, humidity, honey bees ( Apis mellifera ) and varroa in summer: a theoretical thermofluid analysis of the fate of water vapour from honey ripening and its implications on the control of Varroa destructor

This theoretical thermofluid analysis investigates the relationships between honey production rate, nectar concentration and the parameters of entrance size, nest thermal conductance, brood nest humidity and the temperatures needed for nectar to honey conversion. It quantifies and shows that nest humidity is positively related to the amount, and water content of the nectar being desiccated into honey and negatively with respect to nest thermal conductance and entrance size. It is highly likely that honeybees, in temperate climates and in their natural home, with much smaller thermal conductance and entrance, can achieve higher humidities more easily and more frequently than in man-made hives. As a consequence, it is possible that Varroa destructor , a parasite implicated in the spread of pathogenic viruses and colony collapse, which loses fecundity at absolute humidities of 4.3 kPa (approx. 30 gm −3 ) and above, is impacted by the more frequent occurrence of higher humidities in these low conductance, small entrance nests. This study provides the theoretical basis for new avenues of research into the control of varroa, via the modification of beekeeping practices to help maintain higher hive humidities.

Estimating colonies of Plebeia droryana (Friese, 1900) (Hymenoptera, Apidae, Meliponini): adults, brood and nest structure

Estimate of stingless bee colonies including nest structures and quantitative brood and adult individuals are scarce. Here, we describe a new approach to estimate colonial parameters from nest structure, adults and brood. We used five colonies of Plebeia droryana (Friese, 1900) to evaluate colony size and weight of adult and brood. Nest architecture in P. droryana is similar to the species of the same genus but differ to the other stingless bees. In this species, we counted a total of 9 to 12 brood combs and a total of 19 to 25 food pots in the nests. The number of individuals in the colonies is considered small and our estimate was based on individual and group weight. Our study approach may contribute to further detailed studies of the species nest and considering the stingless bees to the pollination of agricultural crops and native flora of tropical regions, it is important to add information about the biology of P. droryana.

Thermoregulation in colonies of africanized and hybrids with Caucasian, Italian and Carniolan Apis mellifera honey bees

This experiment was carried out to study the internal temperature regulation of a colony of Africanized honey bees (AFR), compared with hybrid Caucasian (CAU), Italian (ITA), and Carniolan (CAR) bees, during the period of one year and different size hives located in a sub-tropical region. The instant internal temperature, 33.7 ± 1.5° C for the AFR, 33.5 ± 1.4° C for the CAU, 33.7 ± 1.5° C for the ITA and 33.8 ± 1.4° C for the CAR, did not show any significant difference (P>0.05). The maximum temperature (36.1 ± 2.3° C) was statistically different (P<0.05) from the minimum (27.6 ± 5.3° C). There was no difference (P>0.05) in the mean internal temperature, between the nucleus (31.7 ± 6.3° C) and the brood nest (32.1 ± 5.3° C) measured between two and four o'clock in the afternoon.