The relationship between blood and muscle samples to monitor for residues of the antibiotic enrofloxacin in chickens

Abstract

In 2005, the US Food and Drug Administration withdrew approval for use of enrofloxacin in poultry, thus effectively imposing zero tolerance for residues of this antibiotic in poultry. Conventional residue monitoring for most antibiotics, including enrofloxacin, involves removing poultry carcasses from the processing line and collecting muscle tissues for analysis. Because of the loss of valuable edible products and the difficulties and expense of sampling all the carcasses, only a small portion of carcasses are tested for violative residues. Unlike muscle tissue, blood is readily available from all birds at the beginning of processing and may be used to screen for illegal residues in all poultry carcasses. It is unknown, however, if enrofloxacin concentrations in blood are predictive of muscle concentrations. In an effort to evaluate this relationship, 156 broiler chickens, 5 wk of age, were dosed with either 25 or 50 µg/mL of enrofloxacin for 3 or 7 d, respectively, in the drinking water. Blood and muscle samples were collected at 0, 1, 3, 6, 12, and 24 h (n = 6 birds/group) during the first dosing day, every 48 h during the dosing period, and every 12 h during the withdrawal period for up to 60 h after withdrawal. Enrofloxacin residues were determined in all blood and tissue samples during the dosing periods and in most of the withdrawal period for both doses. These results support the potential to use blood to screen for illegal enrofloxacin residues in edible poultry tissues in an effort to protect the human food supply.

Effect of doxycycline concentrations in chicken tissues as a consequence of permanent exposure to enrofloxacin traces in drinking water

“…The highest doxycycline concentration was observed in the liver, and similar results have previously been reported by other authors (2,11,15,34). In contrast to Reyes-Herrera et al (28), we observed only small differences between the enrofloxacin concentrations in the breast and thigh muscles. This discrepancy may be due to differences in the applied doses.…”

Evaluation of the Presence and Levels of Enrofloxacin, Ciprofloxacin, Sulfaquinoxaline and Oxytetracycline in Broiler Chickens after Drug Administration

“…and consequently increase the infection rate in humans [41]. Because of this, the FDA imposed a zero-tolerance policy for residues of enrofloxacin and ciprofloxacin in broilers, with the target tissue used for monitoring these residues being muscle; this is the tissue with the greatest antibiotic concentration and persistence, with the highest concentration of residues found in the breast muscle [11]. …”

“…However, most published studies that have evaluated the pharmacokinetics or the withdrawal period of enrofloxacin in broiler chickens used microbiological assays [9–11] or high-performance liquid chromatography (HPLC) methods [12–14]. These studies also did not employ the quantitative and confirmatory methods recommended by regulatory agencies for the study of veterinary drugs in animal tissues, such as liquid chromatography-tandem mass spectrometry (LC-MS/MS).…”

Formation of inclusion complex of enrofloxacin with 2-hydroxypropyl- β -cyclodextrin

“…It can be used to treat specific infections and against a broad spectrum of Gram-negative and Gram-positive bacteria in both stationary and growth phases of bacterial replication (Scheer, 1987). Its wide in vivo distribution, unique antimicrobial effect, high bioavailability, less toxicity, and side effects, make it one of the most commonly used antibiotics for treatment of various animal infectious diseases, and a desirable antibiotic choice for difficult-to-treat infections, particularly those that need long-term antibiotic treatment (Divers et al, 2008;Ebert et al, 2011;Reyes-Herrera et al, 2011;Jerjomiceva et al, 2014;Lin et al, 2014;Rico et al, 2014;Andrieu et al, 2015;Nguyen Dang Giang et al, 2015;Phillips et al, 2015;Piras et al, 2015;Carrascosa et al, 2017;Foster et al, 2017;Roth et al, 2017;Strze R pa et al, 2017;Zhu et al, 2017;Rico et al, 2018). The bactericidal activity of enrofloxacin is concentration-dependent, with susceptible bacterial cell death occurring within 20-30 minutes of exposure.…”