5.2.1. Oomen test

This test, even if never ring-tested, is a requirement in Europe and it is based on the method outlined in Oomen et al. (1992).

- In this in-hive method, experimental units are free flying colonies.

- The artificial contamination with AI is ensured using a syrup feeder of 1 litre fitted to the hive for 24 hours.

- Brood development is followed by weekly inspection of individual brood cells.

- Due to environmental variations, this method may not be easily reproducible since the test product may be stored in the combs and not immediately dispensed to the brood by nurse bees.  It may also be diluted by external nectar. No quantitative data can be provided by this test due to the fact that exposure is not controlled.