Residue depletion profiles and withdrawal interval estimations of meloxicam in eggs and ovarian follicles following intravenous (Meloxicam solution for injection) and oral (Meloxidyl®) administration in domestic chickens (Gallus domesticus)

• Published in: Regulatory toxicology and pharmacology 2022-07, Vol.132, p.105170-105170, Article 105170
• Main Authors: Yuan, Long, Lin, Zhoumeng, Dutch, Rachel S., Richards, Emily D., Clapham, Maaike O., Burmas, Nathaniel, Wetzlich, Scott E., Tell, Lisa A.
• Format: Article
• Language: English
• Subjects: Drug residue; Egg withdrawal time; Meloxicam; Pharmacokinetics; Tissue residue depletion
• ISSN: 0273-2300; 1096-0295
• DOI: 10.1016/j.yrtph.2022.105170

Meloxicam is a non-steroidal anti-inflammatory drug (NSAID) commonly prescribed in an extralabel manner for treating chickens in urbanized settings. The objectives of this study were to determine meloxicam depletion profiles in eggs and ovarian follicles and to estimate associated withdrawal intervals (WDI) in laying hens following a single intravenous or repeated oral administration. The observed peak concentration of meloxicam in ovarian follicles were consistently higher than in egg yolk and egg white samples. Terminal half-lives were 31-h, 113-h and 12-h in ovarian follicles, egg yolk and egg white samples, respectively, for repeated oral administrations at 1 mg/kg for 20 doses at 12-h intervals. The terminal half-life following a single intravenous administration at 1 mg/kg was 50-h for ovarian follicles. Meloxicam WDI estimations using ovarian follicle and egg yolk concentration data following 20 doses at 12-h intervals were 36 and 12 days, respectively. Meloxicam WDI estimation using egg yolk concentration data following 8 doses at 24-h intervals was 12 days. These results improve our understanding on the residue depletion of meloxicam from chickens’ reproductive tracts and egg products and provide WDIs to help ensure food safety for humans consuming eggs from treated laying hens. •Meloxicam residue depletion kinetics in eggs and follicles of chickens was studied.•Maximum concentration in ovarian follicles was higher than in egg yolk and white.•Withdrawal interval (WDI) was 12 days in egg yolk after repeated oral exposures.•WDI was 36 days based on follicle data after repeated oral administrations.•The results help derive extralabel WDI to provide safe egg products.