title: Analytical determination of the distribution of flumethrin on the body surface of cattle following topical pour-on application.
abstract: By means of chemical analysis, the distribution behaviour of flumethrin was determined in the hair coat of cattle following topical pour-on application. Flumethrin was applied at 1 mg active ingredient (a.i.) kg-1 body weight along the backline of cattle. It was demonstrated that this compound could be recovered from all hair samples taken on Day 1 following application from dorsal, lateral, ventral and distal body regions in concentrations ranging from 670 to 1 micrograms a.i. g-1 hair, depending on the distance from the site of application. On Days 3, 5 and 10 after treatment, the corresponding concentrations were 125.0-1.5, 23.0-1.0, and 44.0-0.9 micrograms a.i. g-1 hair, respectively. When correlating these values to the body surface of cattle, it is evident that on all sample days and body regions, a concentration of more than 0.01 microgram a.i. cm-2 body surface was present. This amount of active substance is sufficient for effective acaricidal action, as shown by laboratory and field data.
authors.affiliation: Bayer AG, Agrochemicals Centre, Monheim, Leverkusen, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Stendel
authors.forename: H D
authors.initials: HD
authors.lastname: Hamel
authors.forename: H U
authors.initials: HU
authors.lastname: Sieveking
authors.forename: D
authors.initials: D
authors.lastname: Brühne
mesh_terms: D000287:Administration, Topical; D000818:Animals; D002417:Cattle / Q000378:metabolism*; D006197:Hair / Q000737:chemistry / Q000378:metabolism*; D011722:Pyrethrins / Q000008:administration & dosage / Q000493:pharmacokinetics*
chemical_list: D011722:Pyrethrins; C041392:flumethrin