3.1.2. Icing sugar
Icing sugar can be used to detach mites from their host collected in a jar (Macedo et al., 2002) or still in the colony.
Material needed: a wide mouthed canning jar with a lid of which the centre part is replaced by a 2 mm hardware cloth or mesh (Fig. 6a).
1. Place 300 bees in the canning jar and close the lid.
2. Pour 1 heaping table spoon (at least 7 g) of powdered sugar through the mesh or cloth (Fig. 6a).
3. Roll the jar to cover all the bees with sugar (Fig. 6b).
4. Let stand for 1 min.
5. Turn jar upside down over a white surface (Fig. 6c).
6. Shake for 1 min.
7. Place the fallen mites and sugar (Fig. 6d) in a sieve and rinse with 1X phosphate-buffered saline (or other similar saline solution) to rid them of icing sugar particles (Fig. 6e).
8. Place mites on absorbent paper to help them dry up (Fig. 6f).
9. Place the mites collected in a mite-tight container to prevent them escaping.
Place a source of humidity in the container to prevent the mites desiccating until they are used for experiments.
This can also be done using the entire colony fitted with a mesh floor:
1. Remove each frame containing adult bees.
2. Sprinkle with icing sugar so that the frames are all covered.
3. Place back into the colony.
4. Remove the excess icing sugar with the mites from the floor at 10-20 min intervals.
5. Pour over a sieve to remove the sugar and collect the mites.
6. Rinse with 1X phosphate-buffered saline (or other similar saline solution) to rid them of icing sugar particles.
7. Place mites on absorbent paper to help them dry up (Fig. 6f).
8. Place the mites collected in a mite-tight container to prevent them escaping.
Place a source of humidity in the container to prevent the mites desiccating.
Pros: fast and allows for several hundreds of mites to be collected in short time. The treatment is bee-friendly since few individuals die during the process. Workers collected in the jars can be placed back in their colonies where they will be cleaned by their nestmates.
Cons: decreases lifespan of mites (Macedo et al., 2002). This can be a problem if they need to be used for long lasting experiments (> 3 days).
Fig. 6. Collecting mites with icing sugar: a. a heaped table spoon of powdered sugar is poured on 300 honey bees kept in a jar through the lid equipped with a mesh; b. rolling the jar on its side ensures that bees are covered with the sugar; c. the jar is turned upside down and shaken to dislodge the mites; d. mites (2 darker points) and sugar fallen through the mesh on the paper; e. the mites and sugar collected are placed in a sieve over which saline solution is poured to rid the mites from sugar particles; f. the mites are placed on an absorbing paper to accelerate their drying. Photos: Vincent Dietemann.