Residue Depletion of Florfenicol and Florfenicol Amine in Broiler Chicken Claws and a Comparison of Their Concentrations in Edible Tissues Using LC–MS/MS

Abstract

Antimicrobial residues might persist in products and by-products destined for human or animal consumption. Studies exploring the depletion behavior of florfenicol residues in broiler chicken claws are scarce, even though claws can enter the food chain directly or indirectly. Hence, this study intended to assess the concentrations of florfenicol (FF) and florfenicol amine (FFA)—its active metabolite—in chicken claws from birds that were treated with a therapeutic dose of florfenicol. Furthermore, concentrations of these analytes in this matrix were compared with their concentrations in edible tissues at each sampling point. A group of 70 broiler chickens were raised under controlled conditions and used to assess residue depletion. Sampling points were on days 5, 10, 20, 25, 30, 35, and 40 after ceasing treatment, thus extending beyond the withdrawal period established for muscle tissue (30 days). Analytes were extracted using HPLC-grade water and acetone, and dichloromethane was used for the clean-up stage. Liquid chromatography coupled to mass spectroscopy detection (LC–MS/MS) was used to detect and quantify the analytes. The analytical methodology developed in this study was validated in-house and based on the recommendations described in the Commission Decision 2002/657/EC from the European Union. Analyte concentrations were calculated by linear regression analysis of calibration curves that were fortified using an internal standard of chloramphenicol-d5 (CAF-d5). The depletion time of FF and FFA was set at 74 days in claws, based on a 95% confidence level and using the limit of detection (LOD) as the cut-off point. Our findings show that FF and FFA can be found in chicken claws at higher concentrations than in muscle and liver samples at each sampling point.

Risk to Public Health Regarding Doxycycline Residues in Chicken Claws

“…20 In the second research, the depletion of florfenicol (FF) and florfenicol amine (FFA) was studied. 12 For OTC and 4-epi-OTC, the concentration in claws 3 days after ceasing treatment was 2997 μg/kg. FF and FFA were determined in claws 5 days post-treatment at the level of 651 μg/kg, while doxycycline in the presented study was found at the concentration of 3505 μg/kg 4 day after the last antibiotic dose.…”

“…11 Chile reported the exportation of 14 990 tons of chicken claws in 2014. 12 Nowadays, an upward trend in the trade of this product is still observed. 11 Considering that claws have become a highprofit export byproduct for the poultry sector, attention should be paid to the presence of antimicrobial residues.…”

“…16−19 However, for antibiotic residues in claws, there are very few, limited studies. 12,20 No data published have been presented in the literature on the presence of doxycycline in claws thus far, but the official report of the control in the European Union (EU) on the presence of antibiotics in poultry production indicates the most common usage of doxycycline in the treatment of chickens.…”

“…In 2007, broiler claws were in the 15th position of agricultural products most imported by China, while the United States exported about 2.72 million metric tons in 2013 . Chile reported the exportation of 14 990 tons of chicken claws in 2014 . Nowadays, an upward trend in the trade of this product is still observed .…”

Assessment of Three Antimicrobial Residue Concentrations in Broiler Chicken Droppings as a Potential Risk Factor for Public Health and Environment

“…Not long ago, [62] identified FF and FFa residues in broiler chicken feathers up to day 40 after ceasing treatment, detecting concentrations that exceeded 100 μg/kg. Similarly, [63] detected them in chicken claws up to day 25 after ceasing treatment. Thus, the fact that these residues could be identified in our work up to day 10 after ceasing treatment might be a consequence of such prolonged bioaccumulation within feathers and claws, as well as the rapid excretion of these metabolites [64].…”