Pharmacokinetic differences in exposure to camphor after intraruminal dosing in selectively bred lines of goats1

• Published in: Journal of animal science 2010-08, Vol.88 (8), p.2620-2626
• Main Authors: Campbell, E. J., Frost, R. A., Mosley, T. K., Mosley, J. C., Lupton, C. J., Taylor, C. A., Walker, J. W., Waldron, D. F., Musser, J.
• Format: Article
• Language: English
• Subjects: Animal sciences; Goats; Kinetics; Resins; Trees
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/jas.2009-2585

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 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 either at 45 or 60 min after intraruminal administration of camphor may be useful for identifying HJC individual animals from within large populations of goats. [PUBLICATION ABSTRACT]