The authors thank Mona Chambers, Geoffrey Hidalgo and Maurissa Two Two for their technical assistance. We also thank Dr. Earl White for amino acid analysis, Dr. Roger Simonds for analysis of pollen for pesticides, and Drs. Stanley S. Schneider, Vanessa Corby-Harris and Kirk Anderson for their reviews and discussion of earlier versions of the manuscript and many helpful suggestions.

1. Obtaining Beebread from AHB and EHB Colonies
<ol>
	<li>Place pollen traps on honey bee colonies and collect pollen. Grind the pollen into a fine powder (similar to pollen shed from anthers) using a coffee grinder.</li>
	<li>Establish 5 colonies each of AHB and EHB in an enclosed flight area (EFA) so that bees forage only on the pollen provided. To prevent workers from drifting between EHB and AHB colonies, divide the EFA into separate sections so that bees cannot cross between them. Place individual EHB or AHB colonies with 3,500-4,000 worker bees, wax comb with nectar, honey, immature brood and empty comb in each section of the EFA. 
	NOTE: The colonies do not have stored pollen when established. The rate that pollen is stored can be increased by not including a laying queen in the colonies.</li>
	<li>Feed ground pollen to colonies by placing a tray with the pollen in each section of the EFA. Spreading about 60 g of pollen on each tray so that foraging bees can collect it as corbicular loads and store the pollen in their colonies as beebread. Continue providing fresh pollen on each tray daily for 3 weeks.</li>
	<li>Refer to beebread from the European colonies as European beebread (EBB), and from Africanized colonies as Africanized beebread (ABB).</li>
</ol>
2. Feeding Bees in Cages
<ol>
	<li>Place frames of sealed worker brood from AHB and EHB colonies in separate emergence cages in an environmental room set at 32-34 &#176;C and 40% relative humidity..</li>
	<li>When the workers emerge and are about 24 hr old, establish 12 Plexiglas bioassay cages (dimensions = 11.5 x 7.5 x 16.5 cm3) and add either 100 newly emerged EHB or 100 newly emerged AHB worker bees to each cage. Place a section of comb with a known number of either EBB or ABB cells (24-30 cells per cage) in each cage to generate the following treatment combinations: AHB fed ABB, EHB fed ABB, AHB fed EBB and EHB fed EBB. (4 treatments; 6 cages per treatment; 24 cages in total).</li>
	<li>Add vials of water and a 50% honey and water solution formulated by volume to each cage. Refill the honey and water vials daily for the 11 day study period.</li>
</ol>
3. Sampling Worker Bees and Beebread and Estimating Consumption
<ol>
	<li>Sample 10 newly emerged EHB and AHB workers prior to placing them in the cages. Refer to these as Day 0 bees and have them serve as a baseline for hemolymph protein concentrations.</li>
	<li>Remove 10 bees from each cage after they fed on EBB or ABB for 4, 7, and 11 days.</li>
	<li>Place the live bees in individual microcentrifuge tubes and set on ice packs. Select a subsample of four bees for analysis of hemolymph protein concentration.</li>
	<li>After sampling bees on Day-11, count the number of comb cells that still contain beebread. This is a relative measure of beebread consumption.</li>
	<li>Remove the remaining beebread from the cells in each cage and store in separate microcentrifuge tubes according to cage. Keep the beebread samples at -80 &#176;C until analyzed for pH, soluble protein concentration, and amino acid content.</li>
</ol>
4. Estimating pH of Pollen and Beebread
<ol>
	<li>Take six random 0.3 g samples of the pollen fed to bees in the EFA and dissolve it in 300 &#181;l of distilled water. Measure the pH using a waterproof double junction pH spear with an accuracy of +0.01.</li>
	<li>Take 0.3 g sample of beebread that remained after the 11-day feeding period in each cage. Dissolve the beebread in 300 &#181;l of distilled water and measure pH as described for pollen (4.1).</li>
</ol>
5. Protein Analysis
<ol>
	<li>Take six samples of the pollen and a sample of EBB and ABB from each cage. Store samples at -20 &#176;C until analyzed for soluble protein concentration.</li>
	<li>Mix 20 mg of either pollen or beebread with 1,000 &#181;l of 0.1 M phosphate buffer solution (PBS).</li>
	<li>Vortex the mixture for 10 sec and centrifuge at 571.2 x g for 1 min.</li>
	<li>Remove a 10 &#181;l sample of the supernatant and place in wells of a 96 well flat bottom EIA/RIA polystyrene plate. Replicate each sample in three wells.</li>
	<li>Draw hemolymph from bees collected from each cage by inserting a 20 &#956;l capillary tube (that had been heated and pulled to a needle-sharp point) into the right lateral portion of the thorax near the point of attachment of the wings. Collect additional hemolymph, if needed, by inserting the same tube into the membrane between the abdominal tergites.</li>
	<li>Add 1 &#956;l of hemolymph to 9 &#956;l of 0.1 M PBS. Store the hemolymph solution at -20 &#176;C until analysis for soluble protein.</li>
	<li>Determine total soluble protein concentrations in pollen, beebread, and hemolymph samples using a commercial Bradford protein assay kit. Follow the manufacturer&#8217;s instructions.</li>
	<li>Establish a standard curve to estimate soluble protein concentration in the samples by measuring protein absorbance with known protein concentrations in bovine serum albumin (BSA). Measure protein absorbance at 595 nm using a spectrophotometer.</li>
</ol>
6. Amino Acid Analysis
<ol>
	<li>Pool individual samples from comb cells of each colony to create a representative sample of EBB and ABB for analysis.</li>
	<li>Take a 50 mg pollen or beebread sample weighed into autosampler vials, and add 1 ml of distilled water to the vial, along with 100 &#181;l of a 50 ng/&#956;l internal standard solution consisting of d4-alanine, d23-lauric acid, 13C6-glucose and d39-arachidiac acid.</li>
	<li>Cap the sample and sonicate for 5 min.</li>
	<li>Condition an HLB cartridge by adding 1 ml of methanol, equilibrated by adding 1 ml of distilled water followed by the addition of 1 ml of the beebread or pollen sample. Wash the cartridge with 1 ml of 5.0% MeOH/H2O and elute with 1 ml of 80% MeOH/H2O.</li>
	<li>Evaporate the sample to dryness under a stream of nitrogen. Reconstitute the sample with 50 &#181;l of Pyridine and 100 &#181;l of N,O-Bis (trimethylsilyl)trifluoroacetamide + Trimethylchlorosilane (BSTFA + TMCS).</li>
	<li>Cap and incubate the sample at 70 &#176;C for 30 min.</li>
	<li>Allow the sample to cool and transfer it to a clean autosampler vial.</li>
	<li>Cap and place the sample into a Mass Selective Detector interfaced to a gas chromatograph to analyze the samples both for volatile compounds and organic acids. Separate the sugar and organic acids following TMS derivatization with BSTFA + TMCS using a column (30 m x 0.25 mm i.d.) with a 1.0 &#181;m film thickness.</li>
	<li>Set the column oven at 50 C for 2 min, then increase the temperature linearly to 290 &#176;C at 5 C/min. and hold for 7 min. Set the GC injector and GC/MS interface to 250 &#176;C and 290 &#176;C, respectively.
	<ol>
		<li>Use Helium as a carrier at a flow rate of 1.0 ml/min. Set the MS source temperature to 230 &#176;C.</li>
	</ol>
	</li>
	<li>Tune and calibrate the mass spectrometer daily with Perfluorotributylamine (PFTBA). Use a 1 &#181;l injection of PFTBA in the full scan (35-700 amu) positive ion mode to obtain data on the presence and concentrations of amino acids.</li>
</ol>

<ol>
	<li>Brodschneider, R., Crailsheim, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nutrition+and+health+in+honey+bees.">Nutrition and health in honey bees.</a> Apidologie. 41 (3), 278-294 (2010).</li><li>Spivak, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relative+success+of+Africanized+and+European+honey-bees+over+a+range+of+life-zones+in+Costa+Rica.">The relative success of Africanized and European honey-bees over a range of life-zones in Costa Rica.</a> J. Appl. Ecol. 29 (1), 150-162 (1992).</li><li>Schneider, S. S., McNally, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+foraging+patterns+and+colony+energy+status+in+the+African+honey+bee+Apis+mellifera+scutellata.">Spatial foraging patterns and colony energy status in the African honey bee Apis mellifera scutellata.</a> J. Insect Behav. 6 (2), 195-210 (1993).</li><li>Becerra-Guzman, F., Guzman-Novoa, E., Correa-Benitez, A., Zozaya-Rubio, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Length+of+life,+age+at+first+foraging+and+foraging+life+of+Africanized+and+European+honey+bee+(Apis+mellifera)+workers,+during+conditions+of+resource+abundance.">Length of life, age at first foraging and foraging life of Africanized and European honey bee (Apis mellifera) workers, during conditions of resource abundance.</a> J. Api. Res. 44 (4), 151-156 (2005).</li><li>Saltykova, E. S., Lvov, A. V., Ben&#8217;kovskaya, G. V., Poskryakov, A. V., Nikolenko, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interracial+differences+in+expression+of+genes+of+antibacterial+peptides,+Abaecin,+Hymenoptaecin,+and+Defensin,+in+bees+Apis+mellifera+mellifera+and+Apis+mellifera+caucasica.">Interracial differences in expression of genes of antibacterial peptides, Abaecin, Hymenoptaecin, and Defensin, in bees Apis mellifera mellifera and Apis mellifera caucasica.</a> J. Evol. Biochem. Phys. 41 (5), 506-510 (2005).</li><li>Decanini, L. I., Collins, A. M., Evans, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Variation+and+heritability+in+immune+gene+expression+by+diseased+honeybees.">Variation and heritability in immune gene expression by diseased honeybees.</a> J. Hered. 98 (3), 195-201 (2007).</li><li>Gilliam, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbiology+of+pollen+and+beebread:+the+genus+Bacillus.">Microbiology of pollen and beebread: the genus Bacillus.</a> Apidologie. 10 (3), 269-274 (1979).</li><li>Gilliam, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbiology+of+pollen+and+beebread:+the+yeasts.">Microbiology of pollen and beebread: the yeasts.</a> Apidologie. 10 (3), 43-53 (1979).</li><li>Gilliam, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+and+roles+of+non-pathogenic+microflora+associated+with+honey+bees.">Identification and roles of non-pathogenic microflora associated with honey bees.</a> FEMS Microbiology Letters. 155 (1), 1-10 (1997).</li><li>Loper, G. M., Standifer, L. N., Thompson, M. J., Gilliam, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemistry+and+microbiology+of+bee-collected+almond+(Prunus+dulcis)+pollen+and+beebread.+I.+Fatty+acids,+sterols,+vitamins,+and+minerals.">Biochemistry and microbiology of bee-collected almond (Prunus dulcis) pollen and beebread. I. Fatty acids, sterols, vitamins, and minerals.</a> Apidologie. 11 (1), 63-73 (1980).</li><li>Khachatryan, Z. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Predominant+role+of+host+genetics+in+controlling+the+composition+of+gut+microbiota.">Predominant role of host genetics in controlling the composition of gut microbiota.</a> PLoS ONE. 3 (8), e3064 (2008).</li><li>Turnbaugh, P. J., Ley, R. E., Mahowald, M. A., Magrini, V., Mardis, E. R., Gordon, J. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+obesity+associated+gut+microbiome+with+increased+capacity+for+energy+harvest.">An obesity associated gut microbiome with increased capacity for energy harvest.</a> Nature. 444 (7122), 1027-1031 (2006).</li><li>Ley, R. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Obesity+alters+gut+microbial+ecology.">Obesity alters gut microbial ecology.</a> Proc. Natl. Acad. Sci. 102 (31), 11070-11075 (2005).</li><li>Ley, R. E., Peterson, D. A., Gordon, J. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ecological+and+evolutionary+forces+shaping+microbial+diversity+in+the+human+intestine.">Ecological and evolutionary forces shaping microbial diversity in the human intestine.</a> Cell. 124 (4), 837-848 (2006).</li><li>Standifer, L. N., McCaughey, W. F., Dixon, S. E., Gilliam, M., Loper, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemistry+and+microbiology+of+pollen+collected+by+honey+bees+(Apis+mellifera+L.)+from+almond,+Prunisdulcis.+II.+Protein,+amino+acids+and+enzymes.">Biochemistry and microbiology of pollen collected by honey bees (Apis mellifera L.) from almond, Prunisdulcis. II. Protein, amino acids and enzymes.</a> Apidologie. 11 (2), 163-171 (1980).</li><li>Human, H., Nicolson, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nutritional+content+of+fresh,+bee-collected+and+stored+pollen+of+Aloe+greatheadii+var+davyana+(Asphodelaceae).">Nutritional content of fresh, bee-collected and stored pollen of Aloe greatheadii var davyana (Asphodelaceae).</a> Phytochem. 67 (14), 1486-1492 (2006).</li><li>Schneider, S. S., DeGrandi-Hoffman, G., Smith, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+African+honeybee:+Factors+contributing+to+a+successful+biological+invasion.">The African honeybee: Factors contributing to a successful biological invasion.</a> Ann. Rev. Entomol. 49, 351-376 (2004).</li><li>Winston, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+biology+and+management+of+Africanized+honey+bees.">The biology and management of Africanized honey bees.</a> Annu. Rev. Entomol. 37, 173-193 (1992).</li><li>Woyke, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brood-rearing+ef&#64257;ciency+and+absconding+in+Indian+honeybees.">Brood-rearing ef&#64257;ciency and absconding in Indian honeybees.</a> J. Apic. Res. 15 (3/4), 133-143 (1976).</li><li>Woyke, J., Fletcher, D. J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brood+rearing+and+absconding+of+tropical+honey+bees.">Brood rearing and absconding of tropical honey bees.</a> African Bees. , 96-102 (1977).</li><li>Winston, M. L., Otis, G. W., Taylor, O. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Absconding+behavior+of+the+Africanized+honey+bee+in.">Absconding behavior of the Africanized honey bee in.</a> South America. J. Api. Res. 18 (2), 85-94 (1979).</li><li>Schneider, S. S., McNally, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+in&#64258;uencing+seasonal+absconding+in+colonies+of+the+African+honey+bee,+Apis+mellifera+scutellata.">Factors in&#64258;uencing seasonal absconding in colonies of the African honey bee, Apis mellifera scutellata.</a> Insectes Soc. 39 (4), 402-423 (1992).</li><li>Hepburn, H. R., Reece, S. L., Neumann, P., Moritz, R. F. A., Radloff, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Absconding+in+honeybees+(Apis+mellifera)+in+relation+to+queen+status+and+mode+of+worker+reproduction.">Absconding in honeybees (Apis mellifera) in relation to queen status and mode of worker reproduction.</a> Insectes Soc. 46 (4), 323-326 (1999).</li><li>Harrison, J. F., Fewell, J. H., Anderson, K. E., Loper, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Environmental+physiology+of+the+invasion+of+the+Americas+by+Africanized+honeybees.">Environmental physiology of the invasion of the Americas by Africanized honeybees.</a> Integr. Comp. Biol. 46 (6), 1110-1122 (2006).</li><li>DeGrandi-Hoffman, G., Eckholm, B. J., Huang, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+bee+bread+made+by+Africaized+and+European+honey+bees+(Apis+mellifera)+and+its+effects+on+hemolymph+protein+titers.">A comparison of bee bread made by Africaized and European honey bees (Apis mellifera) and its effects on hemolymph protein titers.</a> Apidologie. 44 (1), 52-63 (2013).</li><li>Cappelari, F. A., Turcatto, A. P., Morais, M. M., DeJong, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Africanized+honey+bees+more+efficiently+convert+protein+diets+into+hemolymph+protein+than+do+Carniolan+bee+(Apis+melliferacarnica).">Africanized honey bees more efficiently convert protein diets into hemolymph protein than do Carniolan bee (Apis melliferacarnica).</a> Genet. Mol. Res. 8 (4), 1245-1249 (2009).</li><li>Human, H., Nicolson, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nutritional+content+of+fresh,+bee-collected+and+stored+pollen+of+Aloe+greatheadii+var+davyana+(Asphodelaceae).">Nutritional content of fresh, bee-collected and stored pollen of Aloe greatheadii var davyana (Asphodelaceae).</a> Phytochem. 67, 1486-1492 (2006).</li><li>Bonvehi, J. S., Jorda, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nutrient+composition+and+microbiological+quality+of+honeybee-collected+pollen+in+Spain.">Nutrient composition and microbiological quality of honeybee-collected pollen in Spain.</a> J. Agric. Food Chem. 45 (3), 725-732 (1997).</li><li>Anderson, K. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbial+ecology+of+the+hive+and+pollination+landscape:+Bacterial+associates+from+floral+nectar,+the+alimentary+tract+and+stored+food+of+honey+bees+(Apismellifera).">Microbial ecology of the hive and pollination landscape: Bacterial associates from floral nectar, the alimentary tract and stored food of honey bees (Apismellifera).</a> PLoS ONE. 8 (12), e83125 (2013).</li><li>Southwick, E. E., Roubik, D. W., Williams, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+energy+balance+in+groups+of+Africanized+and+European+honey+bees:+ecological+implications.">Comparative energy balance in groups of Africanized and European honey bees: ecological implications.</a> Comp. Biochem. Physiol. A. 97 (1), 1-7 (1990).</li><li>Spivak, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relative+success+of+Africanized+and+European+honey-bees+over+a+range+of+life-zones+in+Costa+Rica.">The relative success of Africanized and European honey-bees over a range of life-zones in Costa Rica.</a> J. Appl. Ecol. 29 (1), 150-162 (1992).</li><li>Francoy, T. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphometric+and+genetic+changes+in+a+population+of+Apis+mellifera+after+34+years+of+Africanization.">Morphometric and genetic changes in a population of Apis mellifera after 34 years of Africanization.</a> Genet. Mol. Res. 8 (2), 709-717 (2009).</li></ol>

The authors have nothing to disclose.

Using the methods described above, we found that the beebread made by AHB was consumed in greater amounts by both AHB and EHB. Though EHB and AHB consumed similar amounts of each type of beebread, AHB had higher hemolymph protein titers. Findings based on our methods were similar to previous reports where hemolymph protein levels in AHB were higher than in EHB though both were fed the same diets 26 . By measuring consumption of EBB and ABB which were consumed at different rates by both EHB and AHB, it was determined that hemolymph protein concentration in each subspecies could not be raised by increasing food consumption. There seems to be a plateau for hemolymph protein concentration in workers of nurse bee age and that the set point for the plateau is higher in AHB than EHB.
There are several important conditions for establishing colonies for beebread production that will optimize the rate of pollen storage. First, the colonies need frames with open brood. Without open brood to feed, workers will not collect much pollen. Secondly, the colony must be queenless so no additional brood is produced. Brood rearing requires large amounts of pollen, and only excess pollen is stored. In the small colonies established in EFA, there would be little pollen to be stored as beebread if brood areas were expanding so colonies need to be queenless. Finally, for beebread to be made, pollen must be collected as corbicular loads and stored in comb cells. If the pollen is collected in pollen traps, it must be ground to a fine powder before presenting it to the bees so they can collect it as corbicular loads.
The methods to measure the consumption of beebread generated qualitative rather than absolute estimates. The only consumption that was counted was when cells were completely emptied of bee bread. A more accurate estimate of total bee bread consumption might be obtained by removing the bee bread from the cells and making it into a patty that could be weighed before and after the study period. However, we wanted to keep the bee bread in the cells so that the bees could feed on it as they would in a colony and perhaps continue processing it during the study period. The difference in weight of the comb sections before and after the study was not used as an estimate of consumption because the weight might have increased because bees put the diluted honey fed to them in some cells.
The workers also might have added some of the diluted honey to the bee bread. For these reasons, cells containing approximately equal amounts of bee bread before and after the feeding period were counted and generated a qualitative measurement. Still, there was a striking difference between the two types of beebread in the number of empty ABB cells counted compared with EBB after 11 days.
Determining when stored pollen becomes beebread can be difficult because bees continually add pollen to cells. The colonies used for producing beebread were established with frames of open brood so bees would collect pollen. However, the colonies were queenless so there were larvae to feed for only about 9 days after the colony was established. For the remainder of the 3 week period when colonies were in the EFA, the pollen that the bees collected was stored and being converted to beebread. Keeping the stored pollen in the comb cells for an additional 11 days when feeding it to bees in cages also may have continued the processing of pollen to beebread. The conversion of pollen to bee bread takes about 7 days 8. The beebread fed to EHB and AHB had lower pH and reduced protein concentrations compared with the pollen fed. Similar findings of changes in pollen after conversion beebread have been reported by others 7,10,27. Our results differed from previous reports however, in that there were differences in concentrations of certain amino acids between beebread and pollen. The changes in both protein and amino acid concentrations could be due to the activity of proteolytic enzymes, the source of which might be the bees themselves or the microbial communities established in the beebread 7,8,28,29 .
The methods used to measure protein concentration were similar to those previously described to determine the effects of dietary protein on Africanized and European bees 26. As an extension of the methods, we were able to estimate soluble protein in the pollen and beebread. Those methods generated similar findings to previous reports 7,10,27. Our findings provide additional evidence that AHB more efficiently assimilate dietary protein than EHB, and that this could be a key factor in the ecological dominance of AHB in most regions where it has immigrated and become established 30-32.

Nutrition plays a fundamental role in the health and vigor of honey bee colonies and in their establishment as populations. Nutrients from food provide energy and the biochemical components needed for brood rearing, thermoregulation, foraging and immune response. For honey bee colonies, the nutrients needed to grow colony populations and maintain their health come from nectar and pollen. Nectar provides carbohydrates and pollen supplies the remaining dietary requirements such as protein, lipids, vitamins and minerals 1.
Subspecies of honeybees can differ in nutritionally based colony-level parameters such as worker longevity, brood rearing, and mechanisms of social immunity 2-6. These differences might be linked to how food, particularly pollen is processed by the colony and digested in individuals. Pollen is stored in comb cells and through microbially mediated lactic acid fermentation is chemically changed 7-10. The fermented pollen is called beebread. There might be genotypic differences among subspecies in their ability to acquire nutrients from the pollen they collect and store and this could affect colony growth and survival. Genotypic effects on food processing and nutrient acquisition have been documented in other organisms causing some individuals to obtain more nutrients and calories than others while consuming the same foods 11-14.
Here we describe methods used to compare the composition and consumption of beebread made by different subspecies of honey bees. Methods to measure the resulting hemolymph protein titers in worker bees also are described. Previous studies on the nutritional composition of beebread were done with European honey bees (EHB) 10,15,16. However, there may be differences in beebread made by bees of different subspecies even when they feed on the same pollen. EHB and AHB were compared because these subspecies have distinct behavioral and physiological differences that might be related to food processing and nutrient acquisition 17. Some of the most notable differences are that AHB collect and consume more pollen than EHB and seem to convert it more readily into brood 18. AHB colonies have higher swarming rates than EHB and abscond when food resources become limited 19-23. Absconding is rare in EHB. AHB also have higher metabolic rates than EHB 24. The nutritional basis for the colony-level differences between EHB and AHB might be related to the rate of pollen collection and also to its nutrient content (e.g., amino acids and protein) after it is converted to beebread. Beebread consumption and the resulting protein acquisition also might play a role in the colony-level differences between EHB and AHB. Using the developed methods, EHB and AHB made beebread from the same pollen source. The beebread was then fed back to the bees of each subspecies and could determine if bees acquire protein from beebread in a manner distinctive to their subspecies or to the source of the beebread.

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methods for comparing nutrients in beebread made by africanized and european honey bees and the effects on hemolymph protein titers

Honey bees obtain nutrients from pollen they collect and store in the hive as beebread. We developed methods to control the pollen source that bees collect and convert to beebread by placing colonies in a specially constructed enclosed flight area. Methods were developed to analyze the protein and amino acid composition of the pollen and beebread. We also describe how consumption of the beebread was measured and methods used to determine adult worker bee hemolymph protein titers after feeding on beebread for 4, 7 and 11 days after emergence. Methods were applied to determine if genotype affects the conversion of pollen to beebread and the rate that bees consume and acquire protein from it. Two subspecies (European and Africanized honey bees; EHB and AHB respectively) were provided with the same pollen source. Based on the developed methods, beebread made by both subspecies had lower protein concentrations and pH values than the pollen. In general, amino acid concentrations in beebread made by either EHB or AHB were similar and occurred at higher levels in beebread than in pollen. Both AHB and EHB consumed significantly more of the beebread made by AHB than by EHB. Though EHB and AHB consumed similar amounts of each type of beebread, hemolymph protein concentrations in AHB were higher than in EHB. Differences in protein acquisition between AHB and EHB might reflect environmental adaptations related to the geographic region where each subspecies evolved. These differences could contribute to the successful establishment of AHB populations in the New World because of the effects on brood rearing and colony growth.

Beebread was stored in -80 &#176;C for less than a month before being analyzed for pH and protein concentration, and for about 4 months before amino acid analysis. Beebread differed from the pollen in pH and protein concentration (Figure 1). The pH of beebread was lower than the pollen as was the protein concentration. Both EHB and AHB consumed more ABB than EBB (Figure 2).
Levels of soluble protein in the hemolymph of AHB were significantly higher than EHB regardless of the type of beebread they consumed (Figure 3). These differences in hemolymph protein levels occurred even though EHB and AHB consumed similar amounts of each type of beebread. The age of the bees at the time of sampling significantly affected soluble protein concentrations in the hemolymph. Protein concentrations were significantly lower in day-4 bees compared with day-7 or 11 which did not differ.
Of the 10 amino acids that are essential for honey bees, all but histidine were detected in the pollen. In most cases, amino acid concentrations measured in beebread were higher than in the pollen (Figure 4). For example, concentrations of leucine and threonine were about 60% higher in beebread compared with pollen, and valine concentrations were about 25% higher. Alanine, aspartic acid, glutamine, and methionine levels also were higher in beebread than in pollen. Amino acids concentrations did not differ greatly between ABB and EBB with the exception of phenylalanine and cysteine. Phenylalanine levels were about twice as high in ABB compared with either EBB or pollen. Cysteine concentrations were lower in EBB compared with ABB or pollen. Tryptophan was the only amino acid present in higher concentrations in pollen than in EBB or ABB. Concentrations of proline in pollen and ABB were higher than in EBB.
<img alt="Figure 1" fo:content-width="6in" src="/files/ftp_upload/52448/52448fig1highres.jpg" width="600" /> 
Figure 1: Comparisons of pH (A) and soluble protein concentrations (B) in pollen and the beebread made by European (EHB) or Africanized (AHB) honey bees. The pH of pollen was significantly higher than the beebread as determined by analysis of variance (F2,12 = 3725, p &#60;0.0001) followed by a Tukeys W- multiple comparison test. The protein concentration in pollen was significantly higher than in beebread made by EHB (EBB) or AHB (ABB) (F2,27 = 16.49; p &#60;0.0001). Means followed by the same letter are not significantly different at the 0.05 level.
<img alt="Figure 2" fo:content-width="6in" src="/files/ftp_upload/52448/52448fig2highres.jpg" width="600" /> 
Figure 2: The average percentage of cells containing beebread that were completely consumed over an 11 day interval by caged bees. The beebread was made by either European (EHB) or Africanized (AHB) bees using the same pollen source. Means were estimated from five cages of each treatment; those with the same letter are not significantly different at the 0.05 level as determined by a one way analysis of variance (F3,16 = 7.3, p = 0.003) and Tukey&#8217;s W test. This Figure has been modified from 25.
<img alt="Figure 3" fo:content-width="6in" src="/files/ftp_upload/52448/52448fig3highres.jpg" width="600" /> 
Figure 3: The average concentration of protein in hemolymph from European (EHB) or Africanized (AHB) honey bees fed beebread made by European (EBB) or Africanized (ABB) bees for 4, 7, and 11 days. A repeated measures analysis of variance indicated significant differences among the 4 treatment groups (F3,20 = 19.7, p &#60;0.001). Levels of soluble protein in AHB fed ABB were significantly higher than EHB fed ABB (p = 0.008) or EBB (p = 0.018). The age of the bees at the time of sampling significantly affected soluble protein concentrations in the hemolymph. Levels were significantly lower in day-4 bees compared with day-7 (p &#60;0.0001) or 11 (p = 0.001). Day 7 and day11 bees did not differ (p = 0.149). This figure has been modified from25 .
<img alt="Figure 4" fo:content-width="6in" src="/files/ftp_upload/52448/52448fig4highres.jpg" width="600" /> 
Figure 4: Concentrations of amino acids (&#181;g per gram of pollen or beebread) in pollen or the beebread made from it. EBB is beebread made by European bees and ABB was made by Africanized bees. Tryptophan, cysteine, phenylalanine and proline were plotted separately for purposes of clarity in presenting their amounts. This figure has been modified from 25.

Watch this Scientific Journal Video about Methods for Comparing Nutrients in Beebread Made by Africanized and European Honey Bees and the Effects on Hemolymph Protein Titers at JoVE.com

Methods for Comparing Nutrients in Beebread Made by Africanized and European Honey Bees and the Effects on Hemolymph Protein Titers

Here are methods to quantify nutrients in pollen before and after its conversion to beebread by two subspecies of honeybees. We describe techniques to measure beebread consumption and resulting protein titers in both subspecies.

Honey bees obtain nutrients from pollen they collect and store in the hive as beebread. We developed methods to control the pollen source that bees ...

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Universidad de Cartagena UDEC

Research

JoVE Journal

Biology

10.6K Views.  USDA-ARS. Here are methods to quantify nutrients in pollen before and after its conversion to beebread by two subspecies of honeybees. We describe techniques to measure beebread consumption and resulting protein titers in both subspecies. 

Video: Methods for Comparing Nutrients in Beebread Made by Africanized and European Honey Bees and the Effects on Hemolymph Protein Titers

Empirical, Metagenomic, and Computational Techniques Illuminate the Mechanisms by which Fungicides Compromise Bee Health

Growers often use fungicide sprays during bloom to protect crops against disease, which exposes bees to fungicide residues. Although considered &#34;bee-safe,&#34; there is mounting evidence that fungicide residues in pollen are associated with bee declines (for both honey and bumble bee species). While the mechanisms remain relatively unknown, researchers have speculated that bee-microbe symbioses are involved. Microbes play a pivotal role in the preservation and/or processing of pollen, which serves as nutrition for larval bees. By altering the microbial community, it is likely that fungicides disrupt these microbe-mediated services, and thereby compromise bee health. This manuscript describes the protocols used to investigate the indirect mechanism(s) by which fungicides may be causing colony decline. Cage experiments exposing bees to fungicide-treated flowers have already provided the first evidence that fungicides cause profound colony losses in a native bumble bee (Bombus impatiens). Using field-relevant doses of fungicides, a series of experiments have been developed to provide a finer description of microbial community dynamics of fungicide-exposed pollen. Shifts in the structural composition of fungal and bacterial assemblages within the pollen microbiome are investigated by next-generation sequencing and metagenomic analysis. Experiments developed herein have been designed to provide a mechanistic understanding of how fungicides affect the microbiome of pollen-provisions. Ultimately, these findings should shed light on the indirect pathway through which fungicides may be causing colony declines.

Microbial consortia within bumble bee hives enrich and preserve pollen for bee larvae. Using next generation sequencing, along with laboratory and field-based experiments, this manuscript describes protocols used to test the hypothesis that fungicide residues alter the pollen microbiome, and colony demographics, ultimately leading to colony loss.

Growers often use fungicide sprays during bloom to protect crops against disease, which exposes bees to fungicide residues. Although considered ...

Environment

Evaluating the Effect of Environmental Chemicals on Honey Bee Development from the Individual to Colony Level

The presence of pesticides in the beekeeping environment is one of the most serious problems that impacts the life of a honey bee. Pesticides can be brought back to the beehive after the bees have foraged on flowers that have been sprayed with pesticides. Pesticide contaminated food can be exchanged between workers which then feed larvae and therefore can potentially affect the development of honey bees. Thus, residual pesticides in the environment can become a chronic damaging factor to honey bee populations and gradually lead to colony collapse. In the presented protocol, honey bee feeding methods are described and applied to either an individual honey bee or to a colony. Here, the insect growth regulator (IGR) pyriproxyfen (PPN), which is widely used to control pest insects and is harmful to the development of honey bee larvae and pupae, is used as the pesticide. The presenting procedure can be applied to other potentially harmful chemicals or honeybee pathogens for further studies.

Herein we present a method to feed pesticide contaminated food to both an individual honey bee and a beehive colony. The procedure evaluates the pesticide effect on individual honey bees by in vivo feeding of basic larval diet and also on the natural condition of beehive colony.

The presence of pesticides in the beekeeping environment is one of the most serious problems that impacts the life of a honey bee. Pesticides can be ...

In Vitro Rearing of Solitary Bees: A Tool for Assessing Larval Risk Factors

Although solitary bees provide crucial pollination services for wild and managed crops, this species-rich group has been largely overlooked in pesticide regulation studies. The risk of exposure to fungicide residues is likely to be especially high if the spray occurs on, or near host plants while the bees are collecting pollen to provision their nests. For species of Osmia that consume pollen from a select group of plants (oligolecty), the inability to use pollen from non-host plants can increase their risk factor for fungicide-related toxicity. This manuscript describes protocols used to successfully rear oligolectic mason bees, Osmia ribifloris sensu lato, from egg to prepupal stage within cell culture plates under standardized laboratory conditions. The in vitro-reared bees are subsequently used to investigate the effects of fungicide exposure and pollen source on bee fitness. Based on a 2 &#215; 2 fully crossed factorial design, the experiment examines the main and interactive effects of fungicide exposure and pollen source on larval fitness, quantified by prepupal biomass, larval developmental time, and survivorship. A major advantage of this technique is that using in vitro-reared bees reduces natural background variability and allows the simultaneous manipulation of multiple experimental parameters. The described protocol presents a versatile tool for hypotheses testing involving the suite of factors affecting bee health. For conservation efforts to be met with significant, lasting success, such insights into the complex interplay of physiological and environmental factors driving bee declines will prove to be critical.

In Vitro Rearing of Solitary Bees: A Tool for Assessing Larval Risk Factors

Fungicide sprays on flowering plants may expose solitary bees to high concentrations of pollen-borne fungicide residues. Using laboratory-based experiments involving in vitro-reared bee larvae, this study investigates the interactive effects of consuming fungicide-treated pollen derived from host and non-host plants.

Although solitary bees provide crucial pollination services for wild and managed crops, this species-rich group has been largely overlooked in pesticide ...

Measuring Hypopharyngeal Gland Acinus Size in Honey Bee (Apis mellifera) Workers

The nurse hypopharyngeal glands produce the protein fraction of the worker and royal jelly that is fed to developing larvae and queens. These paired glands that are located in the head of the bee are highly sensitive to the quantity and quality of pollen and pollen substitutes that the nurse bee consumes. The glands get smaller when nurses are fed deficient diets and are large when they are fed complete diets. Because nurse hypopharyngeal gland size is a robust indicator of nurse nutrition, it is essential that those studying honey bee nutrition know how to measure these glands. Here, we provide detailed methods for dissecting, staining, imaging, and measuring nurse bee hypopharyngeal glands. We present comparisons of unstained and stained tissue and data that were used to study the impact of pollen on gland size. This method has been used to test how diet impacts hypopharyngeal gland size but has further use for understanding the role of these glands in hive health.

Measuring Hypopharyngeal Gland Acinus Size in Honey Bee Apis mellifera Workers

Hypopharyngeal gland acinus size is a robust measure of nurse honey bee nutrition. Here, we provide a detailed protocol for dissecting, staining, imaging, and measuring nurse bee hypopharyngeal gland acini.

The nurse hypopharyngeal glands produce the protein fraction of the worker and royal jelly that is fed to developing larvae and queens. These paired ...

A Novel Behavioral Assay to Investigate Gustatory Responses of Individual, Freely-moving Bumble Bees (Bombus terrestris)

Generalist pollinators like the buff-tailed bumble bee, Bombus terrestris, encounter both nutrients and toxins in the floral nectar they collect from flowering plants. Only a few studies have described the gustatory responses of bees toward toxins in food, and these experiments have mainly used the proboscis extension response on restrained honey bees. Here, a new behavioral assay is presented for measuring the feeding responses of freely-moving, individual worker bumble bees to nutrients and toxins. This assay measures the amount of solution ingested by each bumble bee and identifies how tastants in food influence the microstructure of the feeding behavior.
The solutions are presented in a microcapillary tube to individual bumble bees that have been previously starved for 2-4 hr. The behavior is captured on digital video. The fine structure of the feeding behavior is analyzed by continuously scoring the position of the proboscis (mouthparts) from video recordings using event logging software. The position of the proboscis is defined by three different behavioral categories: (1) proboscis is extended and in contact with the solution, (2) proboscis is extended but not in contact with the solution and (3) proboscis is stowed under the head. Furthermore the speed of the proboscis retracting away from the solution is also estimated.
In the present assay the volume of solution consumed, the number of feeding bouts, the duration of the feeding bouts and the speed of the proboscis retraction after the first contact is used to evaluate the phagostimulatory or the deterrent activity of the compounds tested.
This new taste assay will allow researchers to measure how compounds found in nectar influence the feeding behavior of bees and will also be useful to pollination biologists, toxicologists and neuroethologists studying the bumble bee&#39;s taste system.

A Novel Behavioral Assay to Investigate Gustatory Responses of Individual, Freely-moving Bumble Bees Bombus terrestris

A novel behavioral assay is described for investigating the short term gustatory responses of the mouthparts of freely-moving bumble bees (Bombus terrestris) toward nutrients and toxins in solution.

Generalist pollinators like the buff-tailed bumble bee, Bombus terrestris, encounter both nutrients and toxins in the floral nectar they collect from ...

Neuroscience

Preparation of Single-cohort Colonies and Hormone Treatment of Worker Honeybees to Analyze Physiology Associated with Role and/or Endocrine System

Honeybee workers are engaged in various tasks related to maintaining colony activity. The tasks of the workers change according to their age (age-related division of labor). Young workers are engaged in nursing the brood (nurse bees), while older workers are engaged in foraging for nectar and pollen (foragers). The physiology of the workers changes in association with this role shift. For example, the main function of the hypopharyngeal glands (HPGs) changes from the secretion of major royal jelly proteins (MRJPs) to the secretion of carbohydrate-metabolizing enzymes. Because worker tasks change as the workers age in typical colonies, it is difficult to discriminate the physiological changes that occur with aging from those that occur with the role shift. To study the physiological changes in worker tissues, including the HPGs, in association with the role shift, it would be useful to manipulate the honeybee colony population by preparing single-cohort colonies in which workers of almost the same age perform different tasks. Here we describe a detailed protocol for preparing single-cohort colonies for this analysis. Six to eight days after single-cohort colony preparation, precocious foragers that perform foraging tasks earlier than usual appear in the colony. Representative results indicated role-associated changes in HPG gene expression, suggesting role-associated HPG function. In addition to manipulating the colony population, analysis of the endocrine system is important for investigating role-associated physiology. Here, we also describe a detailed protocol for treating workers with 20-hydroxyecdysone (20E), an active form of ecdysone, and methoprene, a juvenile hormone analogue. The survival rate of treated bees was sufficient to examine gene expression in the HPGs. Gene expression changes were observed in response to 20E- and/or methoprene-treatment, suggesting that hormone treatments induce physiological changes of the HPGs. The protocol for hormone treatment described here is appropriate for examining hormonal effects on worker physiology.

Here we describe our detailed protocol for the preparation of single-cohort honeybee colonies&#160;&#8211; a useful tool for analyzing the role-associated worker physiology. We also describe detailed protocols for treating workers with juvenile hormone and ecdysone to evaluate the involvement of these hormones in the regulation of worker behavior and/or physiology.

Honeybee workers are engaged in various tasks related to maintaining colony activity. The tasks of the workers change according to their age (age-related ...

Obtaining Specimens with Slowed, Accelerated and Reversed Aging in the Honey Bee Model

Societies of highly social animals feature vast lifespan differences between closely related individuals. Among social insects, the honey bee is the best established model to study how plasticity in lifespan and aging is explained by social factors.
The worker caste of honey bees includes nurse bees, which tend the brood, and forager bees, which collect nectar and pollen. Previous work has shown that brain functions and flight performance senesce more rapidly in foragers than in nurses. However, brain functions can recover, when foragers revert back to nursing tasks. Such patterns of accelerated and reversed functional senescence are linked to changed metabolic resource levels, to alterations in protein abundance and to immune function. Vitellogenin, a yolk protein with adapted functions in hormonal control and cellular defense, may serve as a major regulatory element in a network that controls the different aging dynamics in workers.
Here we describe how the emergence of nurses and foragers can be monitored, and manipulated, including the reversal from typically short-lived foragers into longer-lived nurses. Our representative results show how individuals with similar chronological age differentiate into foragers and nurse bees under experimental conditions. We exemplify how behavioral reversal from foragers back to nurses can be validated. Last, we show how different cellular senescence can be assessed by measuring the accumulation of lipofuscin, a universal biomarker of senescence.
For studying mechanisms that may link social influences and aging plasticity, this protocol provides a standardized tool set to acquire relevant sample material, and to improve data comparability among future studies.

In honey bee workers, aging depends on social behaviors rather than on chronological age. Here we show how worker-types with very different aging patterns can be obtained and analyzed for cellular senescence.

Societies of highly social animals feature vast lifespan differences between closely related individuals. Among social insects, the honey bee is the best ...

Monitoring Colony-level Effects of Sublethal Pesticide Exposure on Honey Bees

The effects of sublethal pesticide exposure to honey bee colonies may be significant but difficult to detect in the field using standard visual assessment methods. Here we describe methods to measure the quantities of adult bees, brood, and food resources by weighing hives and hive parts, by photographing frames, and by installing hives on scales and with internal sensors. Data from these periodic evaluations are then combined with running average and daily detrended data on hive weight and internal hive temperature. The resulting datasets have been used to detect colony-level effects of imidacloprid applied in a sugar syrup as low as 5 parts per billion. The methods are objective, require little training, and provide permanent records in the form of sensor output and photographs.

Sublethal doses of pesticides may affect colonies in ways that are difficult to detect using only periodic or visual methods. Methods to measure total adult bee mass, brood, and food resources by weighing hives and hive parts, photographing frames, and installing sensors, are provided. Data analysis is also addressed.

The effects of sublethal pesticide exposure to honey bee colonies may be significant but difficult to detect in the field using standard visual assessment ...

A 3D Printed Pollen Trap for Bumble Bee (Bombus) Hive Entrances

To verify the plant sources from which bumble bees forage for pollen, individuals must be collected to remove their corbicular pollen loads for analysis. This has traditionally been done by netting foragers at nest entrances or on flowers, chilling the bees on ice, and then removing the pollen loads from the corbiculae with forceps or a brush. This method is time and labor intensive, may alter normal foraging behavior, and can result in stinging incidents for the worker performing the task. Pollen traps, such as those used on honey bee hives, collect pollen by dislodging corbicular pollen loads from the legs of workers as they pass through screens at the nest entrance. Traps can remove a large quantity of pollen from returning forager bees with minimal labor, yet to date no such trap is available for use with bumble bee colonies. Workers within a bumble bee colony can vary in size making size selection of entrances difficult to adapt this mechanism to commercially reared bumble bee hives. Using 3D printing design programs, we created a pollen trap that successfully removes the corbicular pollen loads from the legs of returning bumble bee foragers. This method significantly reduces the amount of time required by researchers to collect pollen from bumble bee foragers returning to the colony. We present the design, results of pollen removal efficiency tests, and suggest areas of modifications for investigators to adapt traps to a variety of bumble bee species or nest box designs.

A 3D Printed Pollen Trap for Bumble Bee Bombus Hive Entrances

We present a non-lethal and automated mechanism to collect pollen from bumble bee (Bombus) workers returning to a hive. Instructions for producing, preparing, installing and using the devices are included. By using 3D-printed objects, modification to the design was timely, efficient and allowed for quick turnaround for testing.

To verify the plant sources from which bumble bees forage for pollen, individuals must be collected to remove their corbicular pollen loads for analysis.  ...

Assessing Agrochemical Risk to Mated Honey Bee Queens

Current risk assessment strategies for honey bees rely heavily upon laboratory tests performed on adult or immature worker bees, but these methods may not accurately capture the effects of agrochemical exposure on honey bee queens. As the sole producer of fertilized eggs inside a honeybee colony, the queen is arguably the most important single member of a functioning colony unit. Therefore, understanding how agrochemicals affect queen health and productivity should be considered a critical aspect of pesticide risk assessment. Here, an adapted method is presented to expose honey bee queens and worker queen attendants to agrochemical stressors administered through a worker diet, followed by tracking egg production in the laboratory and assessing first instar eclosion using a specialized cage, referred to as a Queen Monitoring Cage. To illustrate the method&#39;s intended use, results of an experiment in which worker queen attendants were fed diet containing sublethal doses of imidacloprid and effects on queens were monitored are described.

This protocol was developed to enhance the understanding of how agrochemicals affect honey bee (Apis mellifera) reproduction by establishing methods to expose honey bee queens and their worker caretakers to agrochemicals in a controlled, laboratory setting and carefully monitoring their relevant responses.

Current risk assessment strategies for honey bees rely heavily upon laboratory tests performed on adult or immature worker bees, but these methods may not ...

Methods for Comparing Nutrients in Beebread Made by Africanized and European Honey Bees and the Effects on Hemolymph Protein Titers

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Empirical, Metagenomic, and Computational Techniques Illuminate the Mechanisms by which Fungicides Compromise Bee Health

Evaluating the Effect of Environmental Chemicals on Honey Bee Development from the Individual to Colony Level

In Vitro Rearing of Solitary Bees: A Tool for Assessing Larval Risk Factors

Measuring Hypopharyngeal Gland Acinus Size in Honey Bee (Apis mellifera) Workers

A Novel Behavioral Assay to Investigate Gustatory Responses of Individual, Freely-moving Bumble Bees (Bombus terrestris)

Preparation of Single-cohort Colonies and Hormone Treatment of Worker Honeybees to Analyze Physiology Associated with Role and/or Endocrine System

Obtaining Specimens with Slowed, Accelerated and Reversed Aging in the Honey Bee Model

Monitoring Colony-level Effects of Sublethal Pesticide Exposure on Honey Bees

A 3D Printed Pollen Trap for Bumble Bee (Bombus) Hive Entrances

Assessing Agrochemical Risk to Mated Honey Bee Queens