title: Pharmacokinetic differences in exposure to camphor after intraruminal dosing in selectively bred lines of goats.
abstract: A pharmacokinetic dosing study with camphor was used to determine whether selection lines of high-juniper-consuming goats (HJC, n = 12) and low-juniper-consuming goats (LJC, n = 12) differed in their respective disposition kinetics. Postdosing plasma camphor concentrations were used to examine whether a timed single blood sample collected after intraruminal administration of camphor would be a useful screening test to aid in the identification of HJC. Yearling female Boer x Spanish goats (n = 24) received a single intraruminal dose of monoterpene cocktail (0.270 g/kg of BW) containing 4 different monoterpenes that represented their composition previously reported for Ashe juniper (Juniperus ashei). Camphor, the predominant monoterpene in Ashe juniper, was 49.6% of the mix and was the monoterpene analyzed for this study. Blood samples were taken at 15 time points from 0 to 8 h after dosing. Concentrations of camphor were measured in plasma using solid phase extraction and gas chromatography/flame-ionization detection analysis. Maximal plasma concentration of camphor was greater for LJC than HJC (P = 0.01), and area under the curve extrapolated to infinity was greater for LJC than HJC (P < 0.01). Total systemic exposure (area under the curve) to camphor was 5 times less in HJC goats. We conclude that 1) HJC goats possess internal mechanisms to reduce the bioavailability of camphor, and 2) a blood sample taken at 45 min or at 60 min after intraruminal administration of camphor may be useful for identifying HJC individual animals from within large populations of goats.
authors.affiliation: Texas AgriLife Research Center, Sonora, TX 76950, USA. erika@sonoratx.net
authors.forename: E J
authors.initials: EJ
authors.lastname: Campbell
authors.forename: R A
authors.initials: RA
authors.lastname: Frost
authors.forename: T K
authors.initials: TK
authors.lastname: Mosley
authors.forename: J C
authors.initials: JC
authors.lastname: Mosley
authors.forename: C J
authors.initials: CJ
authors.lastname: Lupton
authors.forename: C A
authors.initials: CA
authors.lastname: Taylor
authors.forename: J W
authors.initials: JW
authors.lastname: Walker
authors.forename: D F
authors.initials: DF
authors.lastname: Waldron
authors.forename: J
authors.initials: J
authors.lastname: Musser
mesh_terms: D000818:Animals; D001947:Breeding; D002164:Camphor / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D004777:Environment; D005247:Feeding Behavior; D005260:Female; D005502:Food; D006041:Goats / Q000378:metabolism*; D018653:Juniperus; D012417:Rumen; D013045:Species Specificity
chemical_list: D002164:Camphor