CYTOMORPHOLOGICAL MODIFICATIONS OF INTESTINAL EPITHELIUM OF BEE (APIS MELLIFERA) PARASITED BY NOSEMA SPP. R zvan-Marius VL GIOIU 1 , Gabriela CHIOVEANU 2 , Nicolae CORNIL 1 , Florica BARBUCEANU 2 1 University of Agronomic Sciences and Veterinary Medicine of Bucharest, 59 Mr ti Blvd, District 1, 011464, Bucharest, Romania 2 Institute of Diagnostic and Animal Health, Bucharest (IDAH), Romania Corresponding author email: razvanvlagioiu@yahoo.com Abstract The work aims to investigate the histological changes produced by the parasite Nosema spp. in bee species Apis mellifera, using as a liquid fixative Dubosq-Brasil and Masson modified coloration. Key words: histological techniques, intestinal epithelium, bees, Nosema spp.. INTRODUCTION Apis mellifera is a pollinating insect constantly exposed of different pathogens especially parasites (Webster et al., 2008, Bailey and Ball, 1991). Among these parasites are microsporidians from Nosema genre. This represents a numerous group of endoparasites with intracellular localisation, who presents a unicellular structure and have the capacity to make spores (Forsgren and Fries 2010). The election place of all species from Nosema genre is represented by the cytoplasm of epithelial cells of digestive mucous tube of adult bee (Webster et al., 2004). MATERIALS AND METHODS Initially, we aimed to realise the histopathological examination on living bees samples with scope to observe tissue modifications as consequence of viral pathogens agents possible transferred by Nosema spp, by kind of Morison corps. In order to determinate existent modifications at intestinal epithelium level, consecutive hemolymph depletion produced by parasitism with Nosema, it was created a probe stamp with living bees gathered from study apiary, respective experimental apiary of Institute for Diagnosis and Animal Health (IDAH) and have been created two samples, sample I which consisted in bees with no clinical signs of any diseases, where parasitological, bacteriological and mycological examinations, didn’t evidenced the evolution of specifically disease and sample II, which consisted in bees from colonies with nosemosis . The samples have been obtained at the end of active season, in October 2012. Every sample, for each Apiary consisted in 25 g living adult bees parasitized by Nosema. For sample creating there have been selected bees which has inserted 1-2 Nosema parasites between abdominal tergites, and one of them presented wings malformations or small abdomen. All bees in the Group II were from honeybee colonies that had isolated brood cells presenting irreversible changes in physical characteristics, of the nymphs and the hatching of bees. Digestive system samples collected from bees belonging to consignment have been fixed in the effectiveness of the jumpers: formalin, Dubosq-Brasil, Carnoy and Lille and at the optimal time interval, i.e. at least 72 hours. 33 Scientific Works. Series C. Veterinary Medicine. Vol. LIX (1) ISSN 2065-1295, ISSN CD-ROM 2343-9394, ISSN Online 2067-3663, ISSN-L 2065-1295