Fylaktou A., Liakos B., Iliadis N.

The resistance of 53 Paenibacillus larvae larvae (White) strains to eleven antibacterial substances included penicillin, streptomycin, erythromycin, gentamicin, kanamycin, oxytetracycline, neomycin, chloramphenicol, sulfamethoxazole-trimetoprim, and furamycin was tested. These strains derived from an equal number of apiaries of Cyprus, were isolated during an epidemiological research. The results of this research showed that 32 out of the 53 strains, were sensitive to all antibacterial substances tested. The rest 21 strains were found resistant to only some of them. Eight strains were resistant to streptomycin, two to chloramphenicol, one to gentamicin, nine to sulfathiazole and one to soulfamethoxazole-trimethoprim. No strain was found to oxytetracycline that is used almost exclusively to control American foulbrood in Cyprus.

Key words: Paenibacillus larvae, American foulbrood, resistant strains, antibiotics, sulfonamides, nitrofurines