Honeybee Health

• Status: Ongoing
• Description: Little is currently known about foulbrood strains in Canadian apiaries. Although our 2016 National Honey Bee Health Survey results revealed EFB symptoms in only 0.58% of hives (18 out of 3,097 surveyed colonies), the presence of the bacterium was detected by molecular methods in 40% of surveyed apiaries. This indicates that the potential for outbreak is very real and should be addressed and studied. This study will generate new knowledge on the infectivity, pathogenicity and virulence of two devastating honey bee brood diseases, American Foulbrood (AFB) and European Foulbrood (EFB). NBDC will use the results of this study to develop more effective diagnostic techniques for the identification of foulbrood and improve the ability to predict disease outbreaks.
• Partners: Alberta Beekeepers Commission , Manitoba Beekeepers Association , BC Honey Producers, Honey Bee Centre
• Funding: Alberta Agriculture and Forestry, British Columbia Honey Producers’ Association, Alberta Beekeepers’ Commission, Manitoba Beekeepers’ Association

Primary Researchers

Patricia Wolf Veiga and Dr. Stephen Pernal

Background

American foulbrood (AFB) is a devastating brood disease affecting honey bees caused by spore-forming bacteria. AFB has been studied intensively in Canada, with most experiments focusing on infection levels and disease management.

European foulbrood (EFB) is another common bacterial brood disease. Although it is considered less prevalent and less severe in North America than AFB, its occurrence is on the rise in some beekeeping areas with potential for a serious outbreak if conditions permit.

Little is currently known about foulbrood strains in Canadian apiaries. Although the 2016 National Honey Bee Health Survey results revealed EFB symptoms in only 0.58% of hives (18 out of 3,097 surveyed colonies), the presence of the bacterium was detected by molecular methods in 40% of surveyed apiaries. This indicates that the potential for outbreak is very real and should be addressed and studied.

Objectives

This project aims to:

1. Develop more effective AFB and EFB diagnostic techniques;
2. Establish the likelihood of developing the disease by studying propagation means in the hive, analyzing infection levels in adult bees and correlating with the development of symptoms; and
3. Genotype local strains, establish relatedness, compare virulence, and assess resistance to oxytetracycline.

Strategy

This three-year study will involve...

• Year 1: NBDC will collect samples from across Western Canada (AB, BC, MB), culture foulbrood strains on selective media, and detect and quantify the bacteria using molecular techniques. We will also apply a Next Generation Sequencing (NGS) analysis to individual foulbrood strains isolated in this study, providing some insights on the difference of infectivity, pathogenicity and virulence possible found among foulbrood isolates. NBDC will develop a new diagnostic protocol of EFB by real-time qPCR (a molecular method)
• Year 2: Established foulbrood cultures will be used for a small-scale AFB and EFB infectivity trial of up to 10 hives each. Adult bees and larvae from infected hives will be evaluated for pathogen levels during the growing season. This evaluation will identify the best practice and conditions to establish a diseased hive for experimentation.
• Year 3: NBDC will conduct a field trial using infected AFB and EFB apiaries in separate locations at least 2 miles apart from one another. Management of colonies will follow standard commercial practices, including control treatments for other diseases and parasites. Disease progression will be monitored, establishing correlation between bacteria levels identified in the lab and presence of symptoms in the field. Our results will provide us with superior ability to assess whether AFB spores and EFB presence in adult bees from apparently healthy colonies could develop into an overt infection.

Outcomes

• Generation of new knowledge on infectivity, pathogenicity and virulence of local bacterial strains causing foulbrood in Canada
• Development of better diagnostic techniques for the identification of AFB and EFB
• Improved ability to predict likelihood of disease outbreaks in the field
• Creation of an essential tool for the implementation of Integrated Pest Management (IPM) practices, giving Veterinaries essential information needed to prescribe antibiotic treatments.

Project Funding

• Alberta Agriculture and Forestry
• British Columbia Honey Producers’ Association
• Alberta Beekeepers’ Commission
• Manitoba Beekeepers’ Association
• Honeybee Centre