Title: ANALYSIS OF OXYTETRACYCLINE IN EXTENDER PATTIES
Submitted to: Apidologie
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 7, 2000
Publication Date: N/A
Interpretive Summary: European and American foulbrood are serious diseases of honey bees, which can be treated or prevented by the application of the antibiotic oxytetracycline (OTC). One of the application methods uses an "extender patty" composed of OTC, shortening, and sugar. The large amount of shortening present makes it difficult to determine the antibiotic concentration. We have developed a separation method which makes it possible to separate the antibiotic in a form that can be easily analyzed. Since resistance to OTC has been observed, it is of interest to extension personnel, bee equipment suppliers, and bee scientists to be able to determine he concentration of this antibiotic.
Antibiotic extender patties, consisting of sugar, vegetable shortening, and oxytetracycline (OTC), are used for treatment/prevention of foulbrood in honey bees. An analytical method was developed to determine the concentration in the patties and to allow a study of deterioration over time. Trituration of a sample with EDTA-treated C18 silica gel, removal of the shortening with isooctane, and elution of the OTC with methanol acetonitrile gave a solution that could be analyzed by HPLC. Different concentrations and total amounts of OTC have been recommended by different authors. Not all newly-procured samples contained the desired level of OTC, and the concentration decreased slowly with time of storage.