Semduramicin in the chicken: tissue residue depletion studies
1992
Lynch, M.J. | Frame, G.M. | Ericson, J.F. | Illyes, E.F. | Nowakowski, M.A.
When biosynthetically prepared 14C-semduramicin sodium, a new anticoccidial ionophore, was fed at 25 ppm in feed to broilers for 7 days, the tissue containing the highest total residues at all withdrawal times was liver. These residues were comprised mainly of unchanged semduramicin sodium (approximately 45%) and an array of more polar, low-level (<O.1 ppm) metabolites in liver of poultry sacrificed six hours after withdrawal. Two metabolites were isolated from chicken bile. They were identified by FAB mass spectrometry and confirmed by proton NMR as A-ring O-desmethyl, and G-ring O-desmethyl compounds. Based on a chemical assay procedure utilizing HPLC with post-column derivatization, unchanged residues of semduramicin sodium declined from 0.166 microgram/g at 6 hours withdrawal to less than 0.017 microgram/g by 24 hours in liver of poultry fed drug in feed at 25 ppm for 44 days.
显示更多 [+] 显示较少 [-]