Honey bee testing at the Animal Health Laboratory

The AHL offers quantitative detection of honey bee (Apis mellifera) pathogens as a routine testing service.  The test results can be used to identify the presence of pathogens, and to assist in the distinction between low-grade latent infection and high-level infection that can lead to disease and declines in honey bee health.  The quantitative PCR test methods for honey bee pathogens listed below are accredited by Standards Council of Canada (SCC) under the AHL flexible scope for PCR assays, as listed on Lab Services ISO/IEC 17025 SCC scope of accreditation.  These assays include:

  • Acute bee paralysis virus (ABPV)
  • Black queen cell virus (BQCV)
  • Chronic bee paralysis virus (CBPV)
  • Deformed wing virus (DWV)
  • Israeli acute paralysis virus (IAPV)
  • Kashmir bee virus (KBV)
  • Sacbrood virus (SBV)

The AHL also offers:

  • Microscopy examination for tracheal mites (Acarapis woodi).
  • Visual detection of Varroa mites (Varroa destructor).
  • PCR detection and DNA sequencing confirmation for small hive beetles.
  • PCR detection of Lotmaria passim, Nosema apis and N. ceranae, Apocephalus borealis.
  • Crithidia mellificae PCR.
  • Spiroplasma apis, Spiroplasma melliferum PCR.
  • Tropilaelaps spp. PCR.
  • Culture and PCR detection of Paenibacillus larvae (American Foulbrood).
  • Culture and PCR detection of Melissococcus plutonius (European Foulbrood).
  • Antimicrobial susceptibility of Paenibacillus larvae.
  • Quantitative detection of vitellogenin (a biomarker for honey bee health).

For research project sample testing, please contact the AHL:


Tel: 1 519 824-4120 ext 54320 or 54976

For field samples submitted through the OMAFRA Apiarist or Apiary Inspectors, please contact:


Tel: 1 519 826-3595


Animal Health Laboratory – University of Guelph testing protocols for honey bees.

Paul Kozak (OMAFRA), Hugh Cai (AHL)

AHL receives calls directly from beekeepers with a variety of questions.  Although we have expertise in the tests themselves, we do not have expertise in determining testing protocols nor the application of results to provide direction for actions in management of bee hive and honey production.

AHL, as a veterinary diagnostic lab, does not have a veterinarian-client-patient relationship with owners and cannot directly provide advice to owners around treatment and management.  AHL does have many tests available.  The details of the tests available can be found in the AHL LabNote 32:

If you do not currently have a VCPR with a veterinarian, there are several veterinarians in Ontario that are interested in bees. There are two options for finding veterinarians:

  1. From the website (The veterinary licensing body) 

(if you go to show more options and chose bees from the patient species)

  1. For beekeepers making a connection with a veterinarian, there is also this series of links from the Ontario Beekeepers’ Association:

General Management Principles – Ontario Apiary Program (Ontario Ministry of Agriculture, Food and Affairs) – including local apiary inspectors and the Provincial Apiarist

A) Winter Mortality:

i) If the beekeeper suspects that the honey bee colony died due to potential pesticide exposure (spring and into the active beekeeping season), contact the following organizations:

  • The OMAFRA Apiary Program – may respond to any underlying pest and disease issues.
  • The Ministry of Environment, Conservation and Parks – addressing pesticide issues and use of pesticides.
  • The Pest Management Regulatory Agency – Health Canada – Provincial Inspection – addressing pesticide issues and use of pesticides.

This following questionnaire gathers all information and is submitted to the organizations listed above:

Managed Honey Bee Mortality Report

  • Further questions may be addressed through the OMAFRA Agricultural Information Contact Centre by calling 1-877-424-1300

ii) Beekeepers may also raise any serious pest or disease to a local apiary inspector (OMAFRA): 

iii) For general guidance on what may have contributed to the death of a honey bee colony(ies) this is a very good document from the Ontario Beekeepers’ Association Technology Transfer Program covering many of the common causes of winter mortality: 

iv) Two relevant OMAFRA documents:

They are both intended as advance material for managing honey bees into winter, and in general.

v) For diagnostics related to winter loss here are the best options:

  • American Foulbrood: If there is a concern with this please have them contact the local apiary inspector (first contact): or the Provincial Apiarist.
  • European Foulbrood: If there is a concern with this please have them contact the local apiary inspector (first contact): ( or the Provincial Apiarist.
  • Nosema: This may be something that beekeepers wish to know more about in relation to winter mortality.  It has been given a lot of attention and some other jurisdictions consider it to be a major factor in winter mortality.  Research in Ontario (Dr. Guzman, U of G) has demonstrated that nosema is not a primary factor in most winter mortality and that it is more an issue in the development of the colony in spring.
  • Viruses: The only testing that would be relevant for winter mortality would be examining bees from adjacent surviving colonies and compare results.  However, there are no thresholds for viruses at this time.
  • Varroa mites: Colony infestation levels for varroa mites can be determined by the beekeeper processing and filtering samples of dead bees to estimate the ratio of mites to bees.
  • Resistant varroa mites: There are discussions taking place between apiary programs in Canada on how to address the risk of amitiraz resistance in varroa mites (see below).  If the beekeeper feels that resistance could be a factor, please have them contact the local apiary inspector ( ) or the Provincial Apiarist.
  • Tracheal mites: may be relevant to winter mortality.
  • Pesticides: It would be very difficult to make any conclusion based on anything that occurred before winter.  In general, any pesticide begins to break down quite rapidly after a day or two. The Agriculture and Food Lab is the source of testing on pesticides for beekeepers and researchers and have a lot of great experience.  They can test various matrices (bees, pollen, honey, wax, water, plant materials, etc.).  There are beekeepers who are interested in getting their bees tested in spring for pesticide exposure that took place in the previous fall or earlier.  This may not yield much usable information.
  • Other issues such as starvation: can sometimes be determined through photographs and questions relevant to the beekeeping management.  See also: Managed Honey Bee Mortality Report

    • Further questions may be addressed through the OMAFRA Agricultural Information Contact Centre by calling 1-877-424-1300

B) For diagnostics on honey bee pests and diseases during the beekeeping season:

There are no validated recommendations at this time.