Methods for comparing beebread made by Africanized and European honey bees and the effects on hemolymph protein titers

Authors: DeGrandi-Hoffman, Gloria; ECKHOLM, BRUCE - Non ARS Employee; HUANG, MING HUA - Eurofins Scientific, Inc

Submitted to: Journal of Visualized Experiments
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/25/2014
Publication Date: 3/17/2015
Publication URL: http://handle.nal.usda.gov/10113/61777
Citation: Hoffman, G.D., Eckholm, B., Huang, M. 2015. Methods for comparing beebread made by Africanized and European honey bees and the effects on hemolymph protein titers. Journal of Visualized Experiments. doi: 10.3791/52448.

Interpretive Summary: Nutrition plays a key role in the health of all organisms. There are genetic factors that influence an organism’s ability to obtain nutrients from their food. Honey bees obtain their nutrients from pollen and nectar. Pollen is stored in comb cells and converted to a fermented honey and pollen mixture called beebread. We used two genetically different races of honey bees; European (EHB) and African (AHB) and fed them the same pollen to test for genetic influences on the conversion to beebread. We also examined the consumption of the beebread made by both races and resulting hemolymph protein levels. We found that beebread made by both races was more acidic than the pollen. Beebread made by EHB was slightly more acidic than AHB. The protein concentration in the beebread made by either race was similar and significantly lower than in the pollen. In general, amino acid concentrations were higher in beebread made by either race compared with pollen. The only exception was tryptophan. The concentrations of amino acids were similar in beebread made by either race except for phenylalanine and cysteine. Levels of phenylalanine were higher in beebread made by AHB than in either the pollen or bee bread made by EHB. Cysteine concentrations were lower in beebread made by EHB compared with pollen or beebread made by AHB. Both AHB and EHB consumed more beebread made by AHB. Protein concentrations in AHB were higher than in EHB regardless of the source of beebread. Differences in the ability to acquire protein from beebread between AHB and EHB might contribute to the successful establishment of AHB populations. This is because higher protein levels in workers can result in greater rates of brood rearing and colony growth.

Technical Abstract: The influence of genotype on the conversion of pollen to beebread and on the ability of bees to acquire protein from it was examined using European and Africanized honey bees (EHB and AHB respectively). Both subspecies were provided with the same pollen source. Pollen stored and converted to beebread by either subspecies had lower protein concentrations and lower 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 compared with 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.