title: Pharmacokinetics and tissue disposition of meloxicam in beef calves after repeated oral administration.
abstract: The objective of this study was to investigate the pharmacokinetics and tissue disposition of meloxicam after repeated oral administration in calves. Thirteen male British × Continental beef calves aged 4 to 6 months and weighing 297-392 kg received 0.5 mg/kg meloxicam per os once daily for 4 days. Plasma meloxicam concentrations were determined in 8 calves over 6 days after first treatment. Calves were randomly assigned to be euthanized at 5, 10, 15 (n = 3/timepoint), and 19 days (n = 4) after final administration. Meloxicam concentrations were determined in plasma (LOQ= 0.025 μg/mL) and muscle, liver, kidney, and fat samples (LOQ = 2 ng/g) after extraction using validated LC-MS-MS methods. The mean (± SD) Cmax , Cmin , and Caverage plasma meloxicam concentrations were 4.52 ± 0.87 μg/mL, 2.95 ± 0.77 μg/mL, and 3.84 ± 0.81 μg/mL, respectively. Mean (± SD) tissue meloxicam concentrations were highest in liver (226.67 ± 118.16 ng/g) and kidney samples (52.73 ± 39.01 ng/g) at 5 days after final treatment. Meloxicam concentrations were below the LOQ in all tissues at 15 days after treatment. These findings suggest that tissue from meloxicam-treated calves will have low residue concentrations by 21 days after repeated oral administration.
authors.affiliation: Agricultural Practices Section, Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
authors.forename: J F
authors.initials: JF
authors.lastname: Coetzee
authors.affiliation: Agricultural Practices Section, Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Mosher
authors.affiliation: Agricultural Practices Section, Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
authors.forename: G R
authors.initials: GR
authors.lastname: Griffith
authors.affiliation: Agricultural Practices Section, Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
authors.forename: R
authors.initials: R
authors.lastname: Gehring
authors.affiliation: Agricultural Practices Section, Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Anderson
authors.affiliation: Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
authors.forename: B
authors.initials: B
authors.lastname: KuKanich
authors.affiliation: Agricultural Practices Section, Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
authors.forename: M
authors.initials: M
authors.lastname: Miesner
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry; D000284:Administration, Oral; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*; D002417:Cattle; D007668:Kidney / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008297:Male; D000077239:Meloxicam; D018482:Muscle, Skeletal / Q000737:chemistry; D013843:Thiazines / Q000008:administration & dosage / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*; D013844:Thiazoles / Q000008:administration & dosage / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D000900:Anti-Bacterial Agents; D013843:Thiazines; D013844:Thiazoles; D000077239:Meloxicam