Samples for laboratory diagnosis of bee diseases
A guide on how beekeepers can prepare and submit samples for laboratory diagnosis of American foulbrood, European foulbrood and nosema in honey bees.
The collection of samples from hives may agitate hive bees including guard bees.
People inexperienced in handling bees and collecting samples should first read Safe beekeeping practices.
It is essential that adequate protective clothing, including a bee veil, is worn and techniques for safe handling of bees are understood before opening hives and collecting samples.
Collecting samples for diagnosis of American and European foulbrood
How to collect larval smears:
- Label a clean, glass microscope slide at one end with your registered brand. This is the brand allotted to you by the department when you registered as a beekeeper. Write an identification for the hive and the apiary (if you have more than one apiary). This will enable you to identify the hive when you receive the diagnosis. Use a spirit-based waterproof pen, or if the slide is frosted at one end, use a pencil.
- Remove a single diseased or suspect diseased honey bee larva (or its remains) from its cell and place it on the labelled glass slide. A clean match can be used to lift the larva from the cell.
- Use the same match to crush and pulp the larva on the slide.
- Use the length of the match to make a thin smear by pushing the pulped remains to the unlabelled end of the slide, and then off the slide.
- Leave the match in the hive or place it in the barrel of the smoker to prevent it from spreading disease to other hives.
- Allow the smear to air dry out of direct sunlight.
- Do not cover the smear with a glass slide or cover slip. Damp larval remains act like glue making removal of the cover in the laboratory almost impossible without shattering the glass.
- Dried smears can be placed in plastic slide carriers or individually wrapped in paper and then placed in a strong cardboard box to prevent them breaking when mailed to the laboratory. An Australia Post box the size of an A5 size book is ideal for this purpose.
- Dried larval remains (scales) are difficult to smear and don't stick to the slide. A scale mixed with a drop of distilled water and smeared when soft, overcomes this problem. Alternatively, the dried remains should be forwarded to the laboratory in a small, clean and unused vial.
Collecting comb samples:
- Cut out a 5×10 cm piece of brood comb containing several diseased or suspect diseased larvae.
- The comb must not contain any honey.
- Wrap the comb in absorbent paper towel. Don't use plastic wrap or airtight containers because condensation will cause fungi and moulds to grow making it difficult for the laboratory diagnostician to find the suspect larvae.
- Use a strong cardboard box (that does not squash the comb) for mailing the sample. If the comb is crushed it will be impossible for the laboratory diagnostician to find the larvae.
- If it is not possible to send the comb immediately — keep the sample fresh by chilling it in a refrigerator.
- After cutting the comb, thoroughly clean the knife to avoid possible spread of disease to other colonies.
Collection of samples for diagnosis of nosema disease
- Collect 30 sick or freshly dead bees from the ground near the hive entrance and place them in a small plastic vial. It does not matter if the bees are dead when they arrive at the laboratory.
- If sick or dead bees cannot be found on the ground near the hive, collect 30 foragers when they land at the hive entrance. If the entrance is closed for a brief period, foragers will land at the entrance and can be easily caught.
- If none of the above options are available, collect bees from top bars of the frames inside the hive, preferably in the honey super where older bees are likely to be found. Spores of nosema are more likely to be found in older bees.
- Chill the samples in a refrigerator to keep them as fresh as possible until forwarded to the laboratory. This will help prevent growth of fungi and moulds.
Information to provide with the samples
Include a note with the sample to provide the laboratory with:
- your name and contact details (address, telephone, fax, email) so the diagnosis can be sent to you
- beekeeper registration brand number allotted by the department
- date sample was collected
- hive number to enable you to identify where the sample was taken
- location (district) of the apiary
- the disease you suspect may be present.
Where to send the samples
Post the samples to:
Veterinary Sample Reception
Gribbles Veterinary Pathology
1868 Dandenong Road
Clayton VIC 3168
For information on fees for these diagnostic services, contact Gribbles directly on 1300 307 190.
It is possible for more than one brood disease to occur in the brood nest of a hive or even in a single comb.
Be sure you get a correct diagnosis by sending samples to the laboratory. There have been instances when well meaning beekeepers have incorrectly diagnosed a disease in a hive resulting in unnecessary loss of colonies and honey production.
Field diagnosis of honey bee brood diseases provides notes and illustrations to assist the field diagnosis of brood diseases including European foulbrood and American foulbrood.
Nosema disease in honeybees provides further details about nosema in bees — laboratory diagnosis will often be the only way of ensuring a diagnosis is correct.