The depletion of residual amoxicillin (AMO) and its metabolites, amoxicillin acid (AMA) and 2,5-diketopiperazine (DIKETO), in Jinghai chickens was studied. Chicken tissue samples (muscle, liver and kidney) were deproteinized with acetonitrile and water and extracted with saturated dichloromethane, and the supernatants were analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). After the drug was withdrawn, the depletion times of AMA and DIKETO were longer in the liver and kidneys than in muscle. In the chicken tissue, the AMA residue levels were higher than the AMO and DIKETO residue levels, and the concentrations of AMA were highest in the kidney and liver. Because AMA is an allergen, we recommend monitoring AMA levels even though maximum residue limits (MRLs) for the metabolites of AMO have not been specified. In addition, the calculated withdrawal times for AMO at doses of 30 and 60 mg/kg chicken body weight were 4.01 and 4.33 days in muscle, 5.17 and 5.78 days in the liver, and 3.92 and 5.19 days in the kidney, respectively. To guarantee food safety, AMO withdrawal times of 6 days are required for doses of 30 or 60 mg/kg chicken body weight.

To Cite This Article: Zhang Y, Xie X, Pang M, Zhao M, Xie K, Wang B, Zhao X, Wang Y, Wang R, Wu H, Zhang G, Zhang T, Dai G and Wang J, 2019. Depletion of residual amoxicillin and its major metabolites in muscle, liver and kidney of chicken. Pak Vet J, 39(1): 19-24. http://dx.doi.org/10.29261/pakvetj/2018.120