Iranian J Parasitol: Vol. 6, No.3, 2011, pp.89 -95 Iranian J Parasitol Open access Journal at http:// ijpa.tums.ac.ir Iranian Society of Parasitology http:// isp.tums.ac.ir Tehran University of Medical Sciences Publication http:// tums.ac.ir Short Communication First Detection of Nosema ceranae, a Microsporidian Protozoa of European Honeybees (Apis mellifera) In Iran *S Nabian1, K Ahmadi2, MH Nazem Shirazi2, A Gerami Sadeghian1 1Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, Iran 2 Veterinary Organization of Iran, Tehran, Iran (Received 17 Feb 2011; accepted 21 July 2011) ABSTRACT Background: Nosemosis of European honey bee (Apis mellifera) is present in bee colonies worldwide. Until recently, Nosema apis had been regarded as the causative agent of the disease, that causes heavy economic losses in apicultures. Nosema ceranae is an emerging microsporidian parasite of European honeybees, A. mellifera, but its distribution is not well known. Previously, nosemosis in honeybees in Iran was attributed exclusively to N. apis. Methods: Six Nosema positive samples (determined from light microscopy of spores) of adult worker bees from one province of Iran (Savadkouh- Mazandaran, northern Iran) were tested to determine Nosema species using previously- developed PCR primers of the 16 S rRNA gene. As it is difficult to distinguish N. ceranae and N. apis morphologically, a PCR assay based on 16 S ribosomal RNA has been used to differentiate N. apis and N. ceranae. Results: Only N. ceranae was found in all samples, indicating that this species present in Iran apiaries. Conclusion: This is the first report of N. ceranae in colonies of A. mellifera in Iran. It seems that intensive surveys are needed to determine the distribution and prevalence of N. ceranae in differ- ent regions of Iran. Keywords: Honeybee, Nosema apis, Nosema ceranae, PCR *Corresponding Author: Tel: +98-021-66924469. nabian@ut.ac.ir 89