HEATTREATMENT
Skrevet af: Camilla J. Brødsgaard & Henrik Hansen. Danmarks Jordbrugs-Forskning, Projektgruppe Biavl
HEAT TREATMENT OF BROOD FRAMES
AN EFFECTIVE PHYSICAL METHOD
- Heat treatment of sealed brood provides an effective control of the varroa mite
- The varroa mite is more sensitive than bee brood to temperatures that lie above the normal brood temperature
- Heat treatment can be carried out in various types of thermostatically controlled boxes
- Only frames without dead brood should be treated
- Below the Borgstadter -Thermo- Box and Apitherm boxes are described.
BORGSTADTER – THERMO – BOX
- One can heat treat 16 -17 day old brood frames from queen caged frames (see previous article
- Treatment lasts for four hours at 44°C
- Few brood injuries – some shortening of the bees life
APITHERM BOX
- Varroa can be treated exclusively with this apparatus
- treatment can be carried out at any time on sealed brood, irrespective of the honey flow, e.g. at the end of May or June
- One makes a decision about how many treatments are required from the results of monitoring surveys.
- One treats brood frames where at least 75% of the cells are sealed. The open brood dies.
- Up to 18 frames can be treated at any one time
- The treatment is carried out for three hours, under which the temperature gradually rises to just under 44° C.
- The bees develop normally and their lifespan is not shortened.
- An Apitherm box, for which the electricity in generated by solar cells, is under development in Germany.
THE EFFECT
- Borgstadter-Thermo- Box: 100% mite mortality immediately
- Apitherm Box: varroa females and nymphs are injured under treatment. The main part die within 24 hours. Those that survive lose their ability to procreate.