Characteristics of Nosema ceranae infection in Serbian honey bee colonies

The incidence, symptoms and consequences of Nosema ceranae infection were monitored in 200 honey bee colonies in Serbia over 5 years (2008–2012) to reveal if they display characteristics described for nosemosis type C. Continual high frequency of N. ceranae-positive colonies was recorded within each study year, ranging from 73 to 98 %. A seasonal pattern in N. ceranae incidence was observed over 4 years (2008–2011). Symptoms traditionally attributed to Nosema apis infection were observed in the majority of N. ceranae-infected colonies, both among surviving and those that died. These symptoms could not serve as predictive markers for colony losses, as they were significantly more frequently observed among surviving colonies in 2010, 2011 and 2012. No clear association between N. ceranae infection and colony losses was affirmed neither during the winter nor during the summer season. Thus, N. ceranae infection in Serbian bees do not fit the characteristics for nosemosis type C.