Bee Health Research (National Honey Board Production Research)
2008 Research Projects
Physiological changes in migratory and non-migratory honey bees: a comparative study
Zachary Huang
Michigan State University
The objectives of this study were to determine whether bees undergoing long distance migration have higher juvenile hormone (JH) levels (aging prematurely) and whether their hypopharyngeal glands are smaller due to less pollen consumption. 2220 samples from bees in California, Florida, Georgia and Michigan were measured. Hypopharyngeal gland size was the most sensitive parameter responding to stresses during migration. JH titer was not a good measurement, because no consistent differences were shown between the migratory and stationary groups. There is a plan to publish the effect of long distance migration on honey bee physiology.
2008 Research Projects
Development of Reproductive Technologies to Facilitate the Safe International Exchange of Genetics
Dr. John Pollard, Dr. Claire Plante and Susan Cobey
UC Davis
Development of Reproductive Technologies to Facilitate the Safe International Exchange of Genetics in the Honey Bee
Objectives
The objective of this project was to develop methods to improve honey bee semen processing and pathogen testing for use in the establishment of import/export protocols. The testing and application of technologies were designed to allow for the development of standardized international protocols for the controlled movement of honey bee germplasm for use in domestic breeding programs. Tech transfer courses offered to the beekeeping community were designed to provide advanced training in honey bee stock improvement techniques.
Specific objectives for this project include:
- Development and testing of semen extenders that include new prophylactic antibiotic mixtures designed specifically for the honeybee.
- Development and testing of molecular diagnostic procedures for the screening of honey bee pathogens.
- Development and testing of an import/export protocol for North America in collaboration with the USDA, APHIS utilizing the results and technologies developed in this proposal.
- Development of annual tech. transfer courses for beekeepers and researchers at the University of California, Davis.
This project is on-going and part of a long term program focused on honey bee stock improvement. A major focus is encouraging, promoting and supporting industry based breeding programs. Other aspects of this program are currently supported by the California State Beekeepers Association and The California Almond Board.
The National Honey Board has funded this continuing work in its 2009 budget.
2008 Research Projects
Quantifying Pesticides in Bees from Declining Colonies and Assessing Gamma irradiation
Jim Frazier, Maryann Frazier and Chris Mullin
Penn State University
Quantifying Pesticides in Bees from Declining Colonies and Assessing Gamma irradiation as a Tool for Pesticide Reduction
The declining health of honey bees in the US has been clearly documented. The cause or causes of CCD and declining health appears to be a combination of factors including mites, diseases, stress and pesticide exposure. Our previous work to survey pesticides in bee bread and wax (funded by AHB) has revealed a chronic toxic chemical burden for honey bees that is a combination of both in-hive and out-of-hive pesticide exposures, the latter from residues in pollen and likely nectar brought into the hive.
Previous sampling of colonies undergoing CCD and control colonies included brood and adult bees for which pesticide analyses were lacking. Funds from this project allowed the pesticide analyses of 24 brood and 16 adult bee samples to be completed and the data added to the large database for the complete CCD study in which 61 different variables were investigated for correlation to CCD. The levels of coumaphos in bee brood from control colonies varied significantly from the levels in CCD colonies and was one of only two factors that covaried with CCD. Results of this study have recently been submitted for publication in the scientific journal, PLoS Biology.
The second objective of this study was to evaluate gamma irradiation as a potential tool for mitigating pesticide residues in honey bee colonies, using wax, pollen, and bee bread samples with measured amounts of pesticide contamination. The Breazeale Nuclear Reactor at Penn State University and a commercial radiation facility Steris Isomedix Services Inc. in South Plainfield, New Jersey were utilized in these studies. Radiation treatment using 27Co60 of individual wax foundation, pollen, and bee bread samples gave highly variable and sporadic decreases of pesticide levels from 6-64% reduction with a dose of 10kiloGrays (kGy)/hr (total dose 25 kGy). Samples spiked with known amounts of the miticides fluvalinate and coumaphos, and the fungicide, chlorothalonil at 100 ppm indicated that even with the higher water content of bee bread that should increase the efficiency of radiation effects, the reduction of pesticides was not reproducible across multiple replicates. While gamma radiation has the potential to mitigate pesticide levels in wax, pollen, and bee bread in colonies, an extensive effort will be required to fully evaluate this potential and to determine if it can be done in a cost effective manner for beekeepers.
Published Paper: vanEngelsdorp D, Evans JD, Saegerman C, Mullin C, Haubruge E, et al. (2009) Colony Collapse Disorder: A Descriptive Study. PLoS ONE 4(8): e6481.doi:10.1371/journal.pone.0006481
Abstract Background: Over the last two winters, there have been large-scale, unexplained losses of managed honey bee (Apis mellifera L.) colonies in the United States. In the absence of a known cause, this syndrome was named Colony Collapse Disorder (CCD) because the main trait was a rapid loss of adult worker bees. We initiated a descriptive epizootiological study in order to better characterize CCD and compare risk factor exposure between populations afflicted by and not afflicted by CCD.
Methods and Principal Findings: Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels), no single measure emerged as a most-likely cause of CCD. Bees in CCD colonies had higher pathogen loads and were co-infected with a greater number of pathogens than control populations, suggesting either an increased exposure to pathogens or a reduced resistance of bees toward pathogens. Levels of the synthetic acaricide coumaphos (used by beekeepers to control the parasitic mite Varroa destructor) were higher in control colonies than CCD-affected colonies.
Conclusions/Significance: This is the first comprehensive survey of CCD-affected bee populations that suggests CCD involves an interaction between pathogens and other stress factors. We present evidence that this condition is contagious or the result of exposure to a common risk factor. Potentially important areas for future hypothesis-driven research, including the possible legacy effect of mite parasitism and the role of honey bee resistance to pesticides, are highlighted.
2008 Research Projects
Improving Honey Bee Health and Reducing Pesticide Use with Mite-Resistant Bees
Greg Hunt
Purdue University
This goal of this project was to breed for bees that are resistant to Varroa mites using the two most important resistance mechanisms, grooming behavior and Varroa-sensitive hygienic behavior (VSH). The long term goal is to foster a Midwestern queen breeding industry and an increase in the number of beekeepers that produce their own queens (micro-breeders).
The researchers monitored 105 colonies for grooming behavior and VSH over the course of the project. One queen was instrumentally inseminated with drones from another selected colony and daughters were also raised from these. Most of the colonies were re-queened during the season from selected stock. Three beekeeper cooperators raised several thousand queens primarily from the Purdue breeding program. These were used to re-queen their hives and sold in nucs, or just as queens to beekeepers in Indiana and nearby states. Several workshops were held to talk to beekeepers about queen rearing and selection for mite resistance, and the National Honey Board was cited as the funding agency for our breeding program. A survey was conducted to determine which breeders Indiana beekeepers usually buy their queens from. Funding for 3 years of continued research has been provided by NCR Sustainable Agriculture Research and Extension (SARE).
2008 Research Projects
Nutritional Changes caused by pollen exposure to Miticides and colony health implications
Dennis vanEngelsdorp and Maryann Frazier
Penn State University
NOTE: As progress has been made in the time between grant application and receiving these funds the objectives of this study have been refined to maximize the significance. This work was also funded by the Florida and Pennsylvania Departments of Agriculture, the USDA_ARS Beltsville bee lab, Penn State University, and the NHB grant: “Treatment and monitoring regimes to ensure colony vigor and prevent fall dwindle disease (now called Colony Collapse Disorder)”
Objectives
1. Conduct an epidemiological survey into the long term consequences of entombed pollen in monitored hives.
2. Quantify and describe the entombed pollen condition
3. Attempt to replicate the entombed pollen condition in the lab.
Progress has been made on objective 1 and 2 and are summarized largely in (vanEngelsdorp, Evans et al.). Using samples collected in this project, Dr Chris Mullin’s team has conducted initial work to identify the pigment(s) responsible for the discoloration of entombed pollen. Further samples have been provided to a team to identify the volatiles in entombed pollen. This work may help identify the cause or processes involved in making entombed pollen.
Attempts to replicate entombed pollen in the lab gave mixed results. Initial attempts to recreate entombed pollen in colonies, supervised by Dr. Jeff Pettis at USDA Beltsville lab have not been successful.
Published Paper: vanEngelsdorp, D., et al. ‘‘Entombed Pollen”: A new condition in honey bee colonies associated with increased risk of colony mortality. J. Invertebr. Pathol. (2009), doi:10.1016/j.jip.2009.03.008
Abstract
Here we describe a new phenomenon, entombed pollen, which is highly associated with increased colony mortality. Entombed pollen is sunken, capped cells amidst ‘‘normal”, uncapped cells of stored pollen, and some of the pollen contained within these cells is brick red in color. There appears to be a lack of microbial agents in the pollen, and larvae and adult bees do not have an increased rate of mortality when they are fed diets supplemented with entombed pollen in vitro, suggesting that the pollen itself is not directly responsible for increased colony mortality. However, the increased incidence of entombed pollen in reused wax comb suggests that there is a transmittable factor common to the phenomenon and colony mortality. In addition, there were elevated pesticide levels, notably of the fungicide chlorothalonil, in entombed pollen. Additional studies are needed to determine if there is a causal relationship between entombed pollen, chemical residues, and colony mortality.
2008 Research Projects
Honey Industry
En Español