Nosema Ceranae DNA in Honey Bee Haemolymph and Honey Bee Mite Varroa Destructor/DNK Nosema Ceranae U Hemolimfi Pčela I Pčelinjem Krpelju Varroa Destructor

Abstract

Honey bee mite Varroa destructor and microsporidium Nosema ceranae are currently considered the most important threats to honey bees and beekeeping. It has been believed that both N. apis and N. ceranae invade exclusively epithelial cells of the honey bee ventriculus. However, some fi ndings suggest that these microsporidia may infect other tissues of honey bees. There are indications that these pathogens could be found in honey bee haemolymph, as the medium for its distribution to anatomically distant tissues. Knowing that V. destructor being an ectoparasitic mite feeds on the honey bee’s haemolymph, the aim of this study was to investigate if DNA of Nosema spp. microsporidia could be found in honey bee haemolymph and in V. destructor.The study was conducted on bee haemolymph and V. destructor mites from 44 Apis mellifera colonies. From each hive five mite individuals and 10 μL of haemolymph (from 4-5 bees) were used as samples for DNA isolation and PCR detection of Nosema spp.The DNA of N. ceranae was confi rmed in 61.36% of V. destructor mites and 68.18% of haemolymph samples. This is the first report of N. ceranae DNA in honey bee haemolymph and in V. destructor mites. The finding of DNA of N. ceranae in V. destructor could be interpreted as the result of mite feeding on N. ceranae infected bee haemolymph. However, for a full confi rmation of the vector role of V. destructor in spreading of nosemosis, further microscopy investigations are required for the detection of spores in both investigated matrices (haemolymph and V. destructor internal tissues).Pčelinji krpelj Varroa destructor i mikrosporidija Nosema ceranae su najznačajniji faktori rizika po zdravlje pčela i pčelarstvo. Dugo se smatralo da N. apis i N. ceranae infi ciraju isključivo ćelije crevnog epitela pčela, međutim neki nalazi ukazuju na prisustvo ovih mikrosporidija i u drugim tkivima. Postoje indikacije da se ovi patogeni mogu naći i u hemolimfi pčela, kao medijumu za njihovu distribuciju do anatomski udaljenih tkiva. S obzirom na to da se V. destructor kao ektoparazit hrani hemolimfom pčela, cilj ovog rada bio je ispitivanje prisustva DNK mikrosporidija roda Nosema u hemolimfi pčela i pčelinjem krpelju V. destructor.Istraživanje je obavljeno na uzorcima pčelinje hemolimfe i pčelinjim krpeljima V. destructor iz 44 društva Apis mellifera. Iz svake košnice je uzorkovano pet krpelja i 10 μL hemolimfe (sakupljene iz 4-5 pčela) koji su korišćeni kao uzorci za izolaciju DNK i ispitivanje prisustva Nosema spp. putem PCR metode.Prisustvo DNK N. ceranae je potvrđeno u 61,36% analiziranih krpelja V. destructor i 68,18% uzoraka hemolimfe pčela, što predstavlja prvu detekciju prisustva DNK N. ceranae u hemolimfi pčela i krpeljima V. destructor. Nalaz DNK N. ceranae u V. destructor može se tumačiti kao rezultat ishrane V. destructor hemolimfom pčela koja je infi cirana sa N. ceranae. Međutim, da bi se potvrdila vektorska uloga V. destructor u širenju nozemoze, potrebna su dalja mikroskopska istraživanja radi detekcije spora u oba ispitivana medijuma (hemolimfi i unutrašnjim tkivima V. destructor krpelja).