Abstract
The minimal inhibitory concentrations (MICs) of tylosin were determined to 67 strains of Paenibacillus larvae subsp. larvae, the causal agent of American Foulbrood (AFB) disease, from different geographical origins. MIC values obtained ranged from 0.0078 to 0.5 microg/ml. These very low values imply that no resistance to tylosin was found in any isolate of the Foulbrood pathogen. The measurement of diseased larvae with AFB-clinical symptoms in three different field studies demonstrated that tylosin treatment could be effective in vivo. No negative effects in colonies were noted at any dosage rates or forms of application. These studies demonstrate that tylosin, as tartrate, can be used to treat AFB in honeybee colonies.
Highlights
American Foulbrood (AFB) disease caused by the spore-forming bacterium Paenibacillus larvae subsp. larvae (P.l. larvae) (Heyndrickx et al, 1996)
The purposes of the present work were to evaluate the susceptibility of 67 strains of P.l. larvae from diverse geographical areas to tylosin by determining their minimal inhibitory concentrations (MIC), since the information about their efficacy in vitro is quite limited (Alippi, 1994; Kochanski et al, 2001; Okayama et al, 1996) and to determine the response of colonies with clinical signs of AFB to tylosin at different doses and forms of application in order to determine the most effective dose for disease control and lack of recurrence of the disease
MYPGP probed adequate for growth and interpretation of MIC values of P.l. larvae and results for P. aeruginosa, E. coli and S. aureus are within the acceptable limits for quality control strains (NCCLS, 1999)
Summary
American Foulbrood (AFB) disease caused by the spore-forming bacterium Paenibacillus larvae subsp. larvae (P.l. larvae) (Heyndrickx et al, 1996) AFB is one of the few bee diseases capable of killing a colony, and has unique problems for prevention and control because the spores can remain viable for long periods. The purposes of the present work were to evaluate the susceptibility of 67 strains of P.l. larvae from diverse geographical areas to tylosin by determining their minimal inhibitory concentrations (MIC), since the information about their efficacy in vitro is quite limited (Alippi, 1994; Kochanski et al, 2001; Okayama et al, 1996) and to determine the response of colonies with clinical signs of AFB to tylosin at different doses and forms of application in order to determine the most effective dose for disease control and lack of recurrence of the disease
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
