The prophylaxis of Nosema disease in bees by laboratory methods - microscopic testing of the beehive products

摘要

The purpose of this study was to monitor the load of Nosemaspp. spores in honey andpollen samples and to evaluate the pertinence of the method in the prophylaxis of Nosema spp.infestation by eliminating contaminated sources used in bee fed. We investigated 26 apiariesfor a period of 3 years at the end of the active bee season, the collected samples consisting inhoney (85 samples), pollen (85 samples) and reserve honeycombs (80 samples). The sampleswere processed and tested for spores of Nosema spp. through the method OIE/2008, adaptedfor samples of honey, honeycomb and pollen. In the beginning and at the end of each activebee season, the infestation degree and the evolution of the disease amongst monitored beeswere investigated. The samples originated from apiaries suspected of nosema disease. Withinthe lot with pollen samples (85 samples), a number of 50 pollen samples belonging to the 4dominant floral categories in Romania (fruit trees, rape, sun-flower, linden) were chosen inorder to determine the infestation level with Nosema spp. spores. Most of the Nosema spp.spores positive samples were represented by the rape and sunflower pollen samples. Testsevidenced the presence of Nosema spp. spores in 220 samples of honey, pollen andhoneycombs of the total of 250 examined samples during the monitoring process. The testsmade on bee samples collected at the end of the beekeeping season, by comparison to the onescollected in the beginning of the following season, demonstrated a significant reduction in theinfestation degree (72%) in bees by eliminating from consumption the sources of infestation(honey and pollen) in the winter season. Testing before the inactive season for Nosema spp.spores in the reserve honey and pollen represents an important prophylactic method againstNosema spp. infestation in bees.