Since 1987 Varroa mite infestations have caused substantial financial losses to beekeepers. Mite infestations are known to decrease size, strength, and productivity and are associated with Colony Collapse Disorder. Currently the majority of the beekeeping industry uses chemical controls for mite and disease problems.
Mite resistant honeybees would ideally eliminate beekeepers/farm hands exposure to pesticides. Recently, a honeybee behavioral trait defined as “varroa sensitive hygiene” (VSH), which effectively breaks the life cycle of the Varroa mite. This is vital tool for an IPM approach to the problem.
We were awarded SARE grants in 2011, and 2012 for field evaluations of several genetic lines of honeybees. In 2013, we were awarded a grant for Artificial Insemination (AI) of queen daughters from these selected genetic lines which are Karnica (K), Ontario Buckfast (OB) and Pennsylvania Survivor Stock (PSS) using select drone semen. We successfully produced 16 AI Queens which then headed nucleus colonies, and which were then measured for Quality Score (QS) and compared to a control group. The QS values are as follows: AI=9.0, OB=10.3, and K=7.5; OB is slightly superior to AI. By applying a size compensation factor of 1.6 the QS for the AI=14.4, which better that OB. Based on these limited data the AI group measured slightly superior than the control. Qualitatively the AI colonies appeared have high vigor and low parasites, although the data shows that they are only slightly superior to the control group. Originally we planned on the open mated OB and K 2012 colonies living through the winter and building up normally during so they could be used for as 2013 control group, but instead they died off or superseded their queens. Therefore the 2012 quality scores were used for the control group, because the concept of quality score is to be able to measure vigor and continued improvement not only from hive to hive, but year over year. To date 4 AI Queens remain alive and will be used for 2014 state breeding programs.
One of our project goals was to share these genetics with other beekeepers; we did this raising and distributing queen-daughters from these AI Queens. Outreach was by power point presentation to the Pennsylvania State Beekeepers Association, Eastern Apiculture Society meetings, website (www.AlwaysSummerHerbs.com), Forum/blog (www.VSHBreeders.com), Facebook (Pennsylvania Queen Bee Improvement Project) and several other smaller conferences. This 2013 breeding program will contribute foundation stock to the 2014/2015 Pennsylvania Queen Bee Improvement Program.
Varroa mite infestations are a documented as link to decreased size, strength, health, and sometimes Colony Collapse Disorder. Weakened colonies are susceptible to secondary, opportunistic diseases such as foulbrood, viruses or Nosema. Currently the majority of commercial beekeeper use treatments of selective insecticide/miticides for Varroa parasites. These treatment methods have come under scrutiny as to their long-term efficacy because of mites developing resistance, and the side effects on bee’s reproductive abilities (brood rearing). Our approach is to develop and use genetically superior, mite resistant (VSH) queens/stock to significantly reduce or eliminate the use of manmade mite chemicals.
The Pennsylvania Queen Bee Improvement Project was established when we were awarded SARE grants (2011 and 2012) for the field evaluations of genetic lines Karnica (K), Ontario Buckfast (OB) and Pennsylvania Survivor Stock (PSS). In 2013, the project was further progressed by using artificial insemination (AI) of select OB and K queen-daughters with PSS/VSH drone semen to control the genetic cross and test whether AI improved the quality of the stock.
The overall objective of the Pennsylvania Queen Bee Improvement Project is twofold: 1) improve the productivity, mite resistance/tolerance, and winter hardiness of Pennsylvania honeybees, and 2) distribute this stock to project participating beekeepers and share the benefits of this research.
Objective one began in 2011 by evaluating Russian (OWA) and Carniolan Karnica (K) stocks of honeybees, and continued in 2012 by evaluating K and OB. These mite tolerant stocks were open mated with our winter hardy PSS drones in relatively isolated bee yards. The results of this research showed that K and OB stock were the highest quality.
In 2013, the project was further progressed by using artificial insemination (AI) of select K and OB queen-daughters and PSS/VSH drone semen to control the genetic cross and test whether AI improved the quality of the stock. Colonies were produced and empirically measured against a control group.
Objective two is to share the best results of our breeding efforts to date with other beekeepers. We grafted over 400 daughter queens from our 2013 AI Queens. These queens were distributed to 5 other beekeepers.
The 2013 project evaluated AI Queens against a control group (C). Sixteen (16) AI Queens were created from K, OB and PSS genetic lines. The AI Queens headed up nucleus colonies at 4 separate bee yards located in Warren, Slippery Rock, Saxonburg, and Dover, PA. The first measurement date occurred when the AI Queens started laying eggs and the nucleus increased in population. The hive strength and mite count was measured. The hive strength was be determined by counting and recording the number of frames of eggs and brood (FB), and frames of honey (FH) in the colony. The mites were counted by the “powder sugar” method. As the powdered sugar coated the bees, they respond by grooming each other, which causes a percentage of the parasitic Varroa mites to fall onto the bottom board. A piece white Integrated Pest Management (IPM) counting board was placed on the bottom of the colony, and the number of mites was counted and recorded. From these field measurements, the Quality Score (QS) was calculated by:
QS= FB + FH – (Mites)
These QS were compared against Control group (C) which is the data from the 2012 colonies.. Originally we planned on the open mated OB and K 2012 colonies living through the winter and building up normally so they could be used as the 2013 control group, but instead they died off or superseded their queens. Therefore the 2012 quality scores were used for the control group, because the concept of quality score is to be able to measure vigor and continued improvement not only from hive to hive, but year over year. The use of QS from year to year is a well established method used by the Buckfast Breeders in the European Union
Note: QS is usually a positive number for 8 and 10 frame boxes. A compensation multiplier of 8/5 (1.6) was applied to 5 frame nucleus colonies to adjust for a smaller geometry/population and normalize the data. This normalization is included on Sheet 1 but was not used to create Graphs 1 and 2 for consistency between the 2012 control group and 2013 data.
AI was used for this study to control the genetic crosses. The process was coordinated by Jeff Berta with the help of Mark Gingrich and Adam Finkelstein and Kelly Rausch from VP Queen Bees. The following photos describe the timeline of the process:
Photo A- Frames of sealed (unemerged) drones were extracted from the target colonies.
Photo B- Drone frames were placed in brood boxes above a drone excluder screen in working colonies, so the drones would not be able to escape after emerging.
Photo C- Drones were captured, and then gently squeezed to expose the semen sac, for semen extraction.
Photo D- Semen was emplaced using special instruments and procedure by VP Queen Bees’ technicians.
Photo E- Close up of insemination equipment.
Photo F- Close up of AI procedure.
Photo G- AI Queen is marked with a number disc, and wings clipped.
Photo H- AI Queens are inspected after CO2 treatment for health and vigor.
Photo I- AI Queens are caged for transport.
Photo J- Jeff Berta and Adam Finkelstein and Kelly Rausch of VP Queen Bees record AI info and pack queens.
Photo K- Jeff Berta is introducing an AI Queen into a nucleus colony.
Photo L- AI Queen number 38 has been accepted and is laying eggs.
Table 1- Summary of 2013 AI Queens documents the AI work performed in June and August.
Table 2- Queen grafting example worksheet, shows the time line used for grafting eggs from the AI Queens to create queen daughters.
The AI Queens were used to create queen daughter by standard grafting methods documented by the following photos:
Photo M- Jeff Berta is selecting and grafting bee larvae to create queen daughters.
Photo N- Example of typical grafting tool with larvae on tip, ready to be transferred to queen cup.
Photo O- Virgin queen cells containing daughter queens.
Photo P- Typical queen bank with caged virgins being fed by nurse bees.
- Table 1 Summary of 2013 Artificially Inseminated Queens
- Picture A-Drone Brood
- Picture B Drones Restricted Above Excluder Screen
- Picture C Extracting Semen from Drone
- Picture F Queen Being Insemenated by VP Queen Bees
- Picture G AI Queen with Number Disc and Clipped Wings
- Picture H AI Queen Being Inspected After CO2 Treatment
- Picture I AI Queens Are Caged
- Photo O Virgin queen cells of queen daughters
- Photo P Caged queen daughters being fed by nurse bees
- Picture D Performing AI Procedure by VP Queen Bees
- Picture E- Equipment for AI Procedure at Gingrich Apiaries
- Picture J Jeff Berta helping Adam Finkelstein and Kelly Rausch from VP Queen Bees
- Table 2- Example of Queen Grafting Worksheet
- Photo M Jeff Berta grafting/transferring larvae into queen cups
- Photo N Grafting tool used to transfer larvea into queen rearing cups
- Picture K Jeff Berta Introducing AI Queens in AlwaysSummer Herbs Apiary in Slippery Rock
- Picture L AI Queen Sucessfully Laying Eggs in Nucleus Colony
2013 AI Queens were created from the best remaining genetics of the 2011 and 2012 field evaluations. A total of 16 AI Queens were produced: six (6) were inseminated on June 22, 2013, and another ten (10) on August 3, 2013, Table 1.
The AI Queens then headed nucleus colonies and began laying eggs. From these eggs, larvae grafts were made to produce daughter queens. Queens were grafted from July through September 2013 by a team of project participant bee keepers. The grafting was performed in Slippery Rock and Dover, PA by Jeff Berta, Mark Gingrich, Bobby Lee Hawranko, Rob Hawranko, and Kathlene Berta. Grafting began about three weeks after the AI procedure so that as many larvae as possible could be obtained before the queens died. 15-30 daughters were grafted from each AI Queen mother, totaling between 60-120 cells per grafting event. The project team grafted over 400 daughter queen cells.
The nurse bees built the queen cells and cared for them. However, a few days before they hatched, the majority of cells were destroyed by the worker bees. Even though cell protector cages were placed around them, workers were still able to get to the cells, leaving only 100 viable daughter queen cells. From these 100 cells, 50 cells were lost during shipping from Slippery Rock to Dover, Saxonburg, and Warren, PA.
The remaining 50 cells were placed in mating nucs and open mated with drones in our breeding yards. From these 50 cells only three (3) daughter queens established successful colonies. Problems with daughter queens establishing colonies were in part due to timing (late in the season) and a high mite count on the bees in mating nucs which caused the colony to collapse.
Poor production of queens was attributed to low hormone levels in AI queens and eggs. This a common problem with AI because the pheromones are different from an open mated queen. Also, the eggs of the AI Queen have a different/lower vitagellin-hormone level, and often signal the worker to supersede the queen. Additional factors contributing to mortality include poor honey flows during grafting and nucleus build up, and possible poisoning by agrochemicals.
Project colonies were measured by counting the number of frames of brood, and honey, and counting the mite, Sheet 1. The 2013 AI Queen and 2012 field measurements are presented in Sheet 1. Sheet 1 was used to create Graph 1 and 2. Graph 1 compares the mite and frame counts between the AI Queens versus the 2012 OB and K breeding lines; mite measured are: AI=2.0, OB=1.1 and K=2.6. Mite counts for OB were slightly superior to AI. Frame counts presented in Graph 1 are: AI=4.2, OB=4.0 and K=3.9; AI is slightly superior to OB. Graph 2 presents the QS (QS=FB+FH-M) calculated from the field data, results are: AI=9.0, OB=10.3, and K=7.5; OB is slightly superior to AI. By applying a size compensation factor of 1.6 the QS for the AI=14.4, which better that OB.
Qualitatively, the AI colonies appeared to have high vigor and low parasites. Quantitatively, however, the data shows that they are only slightly superior to the control group. This discrepancy may be due to the small data set. Continued improvement of AI protocols in 2014 will produce a larger data set which may support the qualitative observations.
The many project accomplishments include:
1) Developed a protocol for selecting breeding stock and sequestering mature drones for subsequent semen collection.
2) Trained 4 participants on AI Queen introduction and queen cell grafting procedures in a collaborative setting.
3) Produced 16 AI queens, and 400 daughter queens for the statewide breeding program.
4) Educated National (JCEP/SARE), Regional (EAS), State (PSBA), and local bee organizations about the project.
5) Connected to worldwide web using Facebook, VSHbreeders.org, and AlwaysSummerHerbs.com.
7) Created an ongoing interest and discussion of future breeding and cooperation in the state between bee keepers and lay persons alike.
Education & Outreach Activities and Participation Summary
The queen bee improvement project was well supported by an increasing number of participants, and more have signed up for 2014.
Outreach was performed by presenting the Queen Bee Improvement Project Power Point presentation at:
Home and Garden Show, Pittsburgh, PA March 10-12, 2013, and
Farm to Table Conference, Pittsburgh, PA March 23, 2013, and
EAS Regional Conf. (Eastern Apiculture Soc.) W. Chester, PA Aug 8, 2013, and
JCEP Galaxy IV (Joint Conf. of Extension Prof.), Pittsburgh, PA Sept 19, 2013, and
PSBA (Pa State Bee Assoc.), Lewisburg, PA Nov 8, 2013.
Online we have a Facebook page: Pennsylvania Queen Bee Improvement Program.
Online Forum participant for state breeding projects at: VSHbreeder.org.
The Pennsylvania Queen Improvement Project continues to gain grass roots support across the state, especially after our presentation to the EAS and the PSBA meetings. We plan on continuing our research in 2014 to create a hardy mite resistant stock for PA potentially savings bee keepers thousands of dollars in replacement stock and chemical mite treatments, and increasing sustainable honey production. Outreach will continue to educate bee keepers on the viability of chemical-free beekeeping. Currently, we have seven (7) beekeepers and two (2) bee clubs committed to next year’s grafting and field trials.
Lessons learned are:
1-Daughter queens should be emerged before shipping because of substantial losses in transit.
2-Nucleus colonies starter bees should be from relatively mite free stock to prevent CCD during queen introduction.
3-Styrofoam Nuc boxes should be purchased for overwinter of AI queens and selected stock.
4-Queen cells should be removed after capping and placed in incubator to prevent nurse bees from destroying them during dearth periods.
5-Mite treatments should be considered for Drone brood colonies because of extreme high mite counts during emergence is overwhelming, and collapses the colony.