title: Clenbuterol Distribution and Residues in Goat Tissues After the Repeated Administration of a Growth-Promoting Dose.
abstract: This study was conducted to investigate the deposition and depletion process of clenbuterol (CL) in goat tissues, plasma and urine after the repeated administration of a growth-promoting dose. The experiment was conducted in 24 goats (21 treated and 3 controls). Treated animals were administered orally in a dose of 16 µg/kg body mass once daily for 21 consecutive days and randomly sacrificed on days 0.25, 1, 3, 7, 14, 21 and 28 of the withdrawal period. CL in goat tissues was extracted with organic solvents and determined using liquid chromatography tandem mass spectrometry. The depletion rates of tissue differed significantly. The highest concentrations of CL in all tissues are detected on day 0.25 of treatment discontinuation. After administration had been discontinued for 28 days, CL still residues in all tissues, especially, in whole eye, where the concentrations reach 363.29 ± 31.60 μg/kg. These findings confirmed that the whole eye, which are rich in pigment, showed a much higher concentration than any other studied tissue during the withdrawal period.
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 10081, PR China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 10081, PR China.
authors.forename: Ting
authors.initials: T
authors.lastname: Yao
authors.affiliation: Institute of Food and Nutrition Development, Ministry of Agriculture, Beijing 10081, PR China.
authors.forename: Yuchang
authors.initials: Y
authors.lastname: Qin
authors.affiliation: Supervision Institute of Veterinary Medicine and Feed of Tianjin, Tianjin 300402, PR China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Yang
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 10081, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 10081, PR China.
authors.forename: Junguo
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 10081, PR China guxu@caas.cn.
authors.forename: Xu
authors.initials: X
authors.lastname: Gu
mesh_terms: D045930:Anabolic Agents / Q000008:administration & dosage / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D000818:Animals; D002681:China; D002853:Chromatography, Liquid; D002976:Clenbuterol / Q000008:administration & dosage / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D004305:Dose-Response Relationship, Drug; D004350:Drug Residues / Q000032:analysis* / Q000378:metabolism; D006041:Goats; D008297:Male; D013058:Mass Spectrometry; D008460:Meat / Q000032:analysis*
chemical_list: D045930:Anabolic Agents; D002976:Clenbuterol