- Animals: bees
- Animal Production: livestock breeding
- Farm Business Management: feasibility study
- Pest Management: genetic resistance
- Production Systems: organic agriculture
Selective breeding of honey bees for multiple traits with a priority on nosema disease resistance should improve production of colonies and reduce the need for the antibiotic fumagillin. Starting a beekeeper initiated breeding program from the nationally recognized, USDA-ARS VSH line of bees should improve this stock to be more productive under local conditions, since these bees were developed under a different climate and operational needs. Demonstrating that individual bee breeders can improve stocks from nationally recognized breeding programs in disease resistance or production under local conditions should encourage more beekeepers to participate in breeding for stock improvement. Improved stock will help beekeepers maintain healthy, sustainable honey bee populations. I propose to conduct a honey bee stock improvement program that selects colonies for important economic traits (rapid spring population growth, production, good brood pattern) and established methods for varroa and brood disease resistance (hygienic behavior and mite suppression). Additionally, this breeding program will evaluate if improvements can be made in the amount of incidences and severity of nosema disease infection. As a requirement of the selection program, measures for the above traits will occur. This will generate economic data on costs and time associated with sampling and trials. If improvements in the areas of selection occur, this will outline the costs associated with these improvements.
Project objectives from proposal:
The selection program will use standardization of management and blocking on starting date to reduce variation, so that genetic based performance can be measured. Selection will use ranking and elimination schedules.
Over 4 weeks, 20 queens per week (80 total) will be raised from 4 breeder queens incorporating the VSH mite resistant line. Daughter queens will be open mated, ensuring considerable genetic variation. Queens will be selected from each 20 queen group. The mother of each daughter queen will be documented.
First stage evaluation: Daughter queens will be started in small, equal sized colonies with 3 combs. Room for colonies to build more combs will be provided. After a period of 21 days, the new queen should be mated, laying, and all brood will be from the new queen that is being evaluated. Starting measures for frames of bees, brood, drawn comb, and food stores will be measured by proportion of coverage of frames. At 42 days after establishment, all emerging bees should be from the new queen. At 63 days after establishment, colonies will again be evaluated for a change in population and strength. Brood disease will be measured at this time by presence or absence of brood dead in cells. The top 10 performing colonies for each 20 colony group will be retained.
Stage two evaluations: The 40 selected colonies will be sampled for varroa mite levels and Nosema spore levels from natural infection. Infection is historically endemic. Mites will be measured by the sugar roll method outlined by the University of Minnesota. Nosema spore sampling will use the standard hemocytometer method by Cantwell (1970). After three months, mites and Nosema spore levels will again be measured so change in infestations can be determined. Four colonies from each group (16 colonies) with the smallest growth in Nosema spores, and secondarily varroa mites, will be selected. These 16 colonies will be evaluated for hygienic behavior using the freeze killed brood method.
Stage three evaluations. If possible, varroa and nosema treatments will be withheld for these 16 colonies. In spring 2013, these colonies will be evaluated for nosema disease, mites, brood disease, and strength. The top 4 performing colonies based on these measures, and hygienic behavior, will be selected as mothers for queens produced in 2013. The selection process for 2012 will be repeated on new, 2013 queens.
Measures of stock improvement: In 2013, an additional 20 queens will be raised from one or more of the original 4 breeder queens used in 2012, depending on how many survive. These daughter queens will be placed into the evaluation scenario. This will create a reference population of 1st generation daughters to compare with 2nd generation daughters within the same year. This will prevent differences in disease pressure during different years from affecting the results. Statistical comparisons will be made to compare colony measures between generations.
Breeder queen evaluation: all breeder queens used (8) will be evaluated for the same measures to look for correlations with daughters, indicating heritable traits.