Detection of Nosema spp. in Worker Bees of Different Ages During the Flow Season

Abstract

S u m m a r yThe aim of this study was to identify which Nosema species infect those Apis mellifera worker bees performing different functions in the colony. Samples were taken from different places inside and outside the hive, in the honey fl ow season. In February 2010, winter hive debris from 30 colonies was analyzed, and based on the microsporidian species identifi ed by multiplex PCR. The following bee colonies (none of which displayed clinical symptoms of the disease) were selected for further analyses to determine the occurrence of microsporidian parasites: 1) colony A/C infected with Nosema apis and N. ceranae (mixed infection), 2) colony A infected with N. apis, 3) colony C -infected with N. ceranae, and 4) colony K -the control, which was free of infection. Between April and August, 20 nurse bees from frames of open brood, and 20 forager bees returning to the hive from pollen-collecting trips were randomly selected from each colony at 30-day intervals. The results of the study indicate that the microsporidian species is determined not only by the type of worker bee (sampling site), but also by the period (month) of the sample collection. Our fi ndings also suggest that regardless of the type of initial infection, bees infected by different microsporidian species and bees free from infection can coexist in colonies.

Evaluation of the Effectiveness of Selected Treatments of Nosema Spp. Infection by the Hemocytometric Method and Duplex Pcr

“…Duplex PCR confi rmed the presence of different microsporidia species in worker bees sampled from the same colony on different dates. The above results validate our previous observations [21] that worker bees infected with different Nosema species can inhabit the same colony [25]. Meana et al [26] also demonstrated that the origin of the sampled material plays an important role in the identifi cation of N. ceranae spores.…”

“…The effectiveness of the analyzed treatments was evaluated by the hemocytometric technique based on the number of spores, but this method was not used to identify Nosema pathogens to species level because it does not enable species identifi cation [21]. Microsporidia species were validated by duplex PCR.…”

Detection of Nosema spp. in worker bees, pollen and bee bread during the honey flow season

“…Every month from April to September 60 hive bees (HB) were sampled randomly directly from honey combs in the central part of the nest, and 60 forager bees returning to the hive with pollen (FB) were sampled from the beehive entrance using a special tool. Multiplex PCR was used to separately analyse worker bees and pollen brought by them (Sokół and Michalczyk 2012). Pollen grains from forager bees were collected using sterile tweezers.…”