A scientific note on incidence of Nosema apis and Nosema ceranae in Slovakia during the years 2009 and 2010

Abstract

During the last few years a new kind of nosemosis was diagnosed in the bee colonies in the territory of Europe. In Slovakia the causative agent Nosema ceranae was confirmed in 2008. The aim of our study was to monitor the prevalence of mono infection and co-infection of both species N. apis and N. ceranae by using polymerase chain reaction (PCR). The analysis was performed on 72 samples of dead bees, which were collected from bee colonies representing all regions of the country in the years of 2009 and 2010. Prior to PCR analyses positive samples were selected by microscopic examination, confirming the presence of Nosema sp. spores. In the year 2009, N. apis mono infection was diagnosed overall in one sample. The N. ceranae mono infection was diagnosed in 16 samples, while N. apis + N. ceranae co-infection was diagnosed in 2 samples. In three samples causative agent was not identified by differential diagnostics and those were considered as Nosema spp. positive. The ascertained prevalence of N. apis and N. ceranae was 14.3 % and 85.7 %, respectively. In the year 2010, the N. apis mono infection was not diagnosed, while N. ceranae mono infection was diagnosed in 27 samples and N. apis + N. ceranae co-infection was confirmed in 3 samples. The ascertained prevalence of N. apis and N. ceranae was 9.1 % and 90.9 %, respectively. During the period of two years (2009 - 2010), a gradual increase in the prevalence of Nosema ceranae and decrease in the prevalence of Nosema apis was recorded in Slovakia.