Medication with fenbendazole in feed: plasma concentrations and effects on hepatic xenobiotic metabolizing enzymes in swine

MIRÓ, MARÍA VICTORIA; LIFSCHITZ, ADRIÁN; ICHINOSE, PAULA; LANUSSE, CARLOS; LARSEN, KAREN; VIRKEL, GUILLERMO

VETERINARY RESEARCH COMMUNICATIONS

SPRINGER

Año: 2022

0165-7380

Fenbendazole (FBZ), a benzymidazole (BZD) anthelmintic drug, is used for in-feed medication in pigs. BZD-containingdrugs may induce cytochrome P450 isozymes (CYPs), particularly those members of the CYP1A subfamily. The currentresearch evaluated the plasma and liver availability and metabolism of FBZ and its metabolites, oxfendazole (OFZ) andfenbendazole sulphone (FBZSO2), after the administration of the parent drug in feed, and characterized the effect of thesustained administration of the anthelmintic on the catalytic activities of xenobiotic metabolizing enzymes in pig liver.Five female Landrace piglets remained untreated (controls), and other six were treated with a pre-mix of FBZ, combinedwith feed, for 9 consecutive days as usually is recommended. Blood samples were collected from each treated animal upto day 9 and analyzed by HPLC; all animals were slaughtered for preparation of liver microsomes. Plasma concentrationratios OFZ/FBZ and FBZSO2/OFZ increased significantly (p