EPIZOOTIC STATUS OF APIARIES WITH MASSIVE LOSSES OF BEE COLONIES (2008-2009)

Abstract

Summary In 2008 and 2009, winter bee colony mortality in apiaries showed losses which ranged from 30% to 100%. Analyses of tests results obtained from 1000 colonies (from 142 apiaries) were performed to determine the impact of pathogens on the winter bee colony mortality in apiaries. Relationships between individual pathogens were also determined. Dead bees were sampled separately from an average of 7 colonies in each apiary, and the presence of V. destructor, Nosema spp. and viruses: ABPV, CBPV, IAPV, DWV was detected. Co-infection with 3 or 4 pathogens was detected in over 60% of bee colonies. Infestation of V. destructor was found in 88.7% of the colonies while infection of deformed wing virus (DWV) in 76%. A similar number of colonies (74%) were infected with Nosema spp. parasites. Acute bee paralysis virus (ABPV) was detected in 35% of the examined colonies and chronic bee paralysis virus (CBPV) was found in only 7,8% of the colonies. The level of Varroa destructor and Nosema spp. infestation was high (averaged 192 mites per sample and 18 million Nosema spores per bee). Severe colony losses in examined apiaries could be attributed to the wide prevalence of V. destructor with DWV and ABPV infections, and/or Nosema spp. infestation. Losses can also be attributed to the co-occurrence of these pathogens in bee colonies and their total negative impact on the bees.