Tissues Of Food-producing Animals Research Articles

The "steric-like" inhibitory effect and mechanism of doxycycline on florfenicol metabolism: Interaction risk.

Most of the studies on doxycycline (DOX) and florfenicol (FF) remain focused on the improvement of antimicrobial activity and antimicrobial spectrum, and there is no relevant report on whether there is interaction between the two drugs after the combination. This research study evaluated the effect of DOX on FF metabolism in vitro and its mechanisms. The findings of this study showed that DOX inhibits FF metabolism in two ways. Firstly, DOX significantly inhibits the expression of CYP3A29, leading to the slower metabolism of FF; secondly, DOX affects the binding of FF to R106 and R372 by competing for the R372 and/or by a "steric-like effect", thus slowing down FF metabolism, which may increase the residual concentration of FF in edible tissues of food producing animals.

A rapid analysis of Bisphenol A using MISPE coupled with HPLC-FLD in tissues of food-producing animals

Bisphenol A (BPA) is a highly-produced organic compound of anthropogenic origin with a wide-range use and is ubiquitously present in both living organisms and the environment. A previously published analytical method for testing of the free (aglycone) BPA in foodstuffs was simplified and optimized for sheep muscle tissue, kidney and liver, by using only a single MISPE purification step allied with HPLC-FLD analysis. The recovery rates and RSD values over a concentration range of 1–10 µg/kg were in the range of 67‒86% and 3‒34%, respectively, while linearity in the matrix, represented by the r2, was ≥0.999. LOD values were 0.5‒1 µg/kg and LOQ values were 1 µg/kg. The analytical method used is a contribution to the field of veterinary toxicology and food testing and also proved to be applicable for other food-producing animal species, e.g. pigs, poultry and freshwater fish. The MISPE sorbent material for testing of BPA was reusable, with up to five re-use cycles without significant loss in performance characteristics.•The paper reports on a rapid determination of free (aglycone) BPA in tissues of food-producing animals by HPLC-FLD and presents a substantial improvement of analytical performance with regard to time- and cost-savings, as well as environmental protection.•MISPE is an advanced analytical technology, and the results proved that in a single and simplified SPE step it had good performance characteristics such as selectivity, recovery and precision, allied with low LOD and LOQ values.•It was proved that MISPE BPA cartridges could be used at least five times without significant loss of methodological recovery and precision.

Multi-residues UHPLC–MS/MS analysis of 53 antibacterial compounds in poultry feathers as an analytical tool in food safety assurance

Under the EU official monitoring programs, the antibiotics are controlled in tissues of food producing animals. However, regarding the overuse of medicines in veterinary practice, there is a strong need to find an alternative to post-mortem analysis of antibiotics. The use of feathers, as an unconventional matrix, enable to control of birds treatment during breeding.Thus, a novel ultra-high performance liquid chromatography–tandem mass spectrometry method for the analysis of 53 compounds from 11 groups of antibacterials, including penicillins, cephalosporins, macrolides, tetracyclines, quinolones, sulfonamides, aminoglycosides, pleuromutilins, diaminopirymidynes, diaminopirymidynes derivatives and lincosamides in chicken feathers has been developed. The isolation of analytes by solvent extraction method with oxalic acid, Na2EDTA and acetonitrile was performed. The extracts were cleaned by filtration with OASIS HLB cartridges. Chromatographic separation was achieved on a Zorbax SB-C18 analytical column using mobile phase consisting of 0.025% heptafluorobutyric acid and acetonitrile. All compounds were successfully validated, with good sensitivity, accuracy and precision. The developed method gives an opportunity to effective monitoring, whether chickens have been given antibiotics, as well as let to identify the medicines that were used.

Application of the AhR Reporter Gene Assay for the Determination of PCDD/Fs and DL-PCBs in Feed Samples.

IntroductionPolychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) belong to a well-known group of pollutants. Present in feedstuffs, they bioaccumulate in tissues of food-producing animals. Food is the source of over 90% of human PCDD/Fs and DL-PCBs intake. Thus, feed control is one of the pillars of the EU strategy and a mean of reducing human exposure. The article presents AhR based reporter gene bioassay method for PCDD/Fs and DL-PCBs analysis in feed and its validation results.Material and MethodsAnalytes were extracted from samples with fat. Subsequently, fat and other interferences were removed from extract using sulphuric acid modified silica. Extract was further cleaned and PCDD/Fs separated from DL-PCBs using carbon column. Contaminants detection was performed using H1L6.1c3 cell line, which produces luciferase in response to AhR ligands present in extract.ResultsPerformance characteristics (repeatability, reproducibility, and apparent recovery) fulfil the requirements of Regulation 2017/771/EU. The positive correlation between bioassay and reference HRGC-HRMS method was confirmed. Moreover, the role of screening method used in connection with the confirmatory HRGC-HRMS method in providing feed and food safety has been discussed.ConclusionBioassay is a useful method for dioxin and DL-PCBs analysis, allowing cost reduction of monitoring programmes with minimal risk of false negative results.

Antibiotic residues in broiler and layer meat in Chittagong district of Bangladesh

Aim: The present study was described thin layer chromatography (TLC) and ultra-high performance liquid chromatography (UHPLC) method for the detection of antibacterial substances in poultry muscle (breast and thigh), kidney, and liver. Materials and Methods: TLC method was used for screening detection of tetracycline, amoxicillin, ciprofloxacin, and enrofloxacin residues in poultry tissues. The samples were extracted with trichloroacetic acid (30%), diethyl ether, followed by detection in pre-coated TLC paper on ultraviolet detector. The UHPLC method was used for the quantification of antimicrobial residues in poultry tissues. Results: The residues of tetracycline were 48% in livers, 24% in kidneys, 20% in thigh muscles, and 24% in breast muscles. Ciprofloxacin residues were found 44% in liver, 42% in kidneys, 34% in thigh muscles and 30% in breast muscles. Enrofloxacin residues were found 40% in liver, 34% in kidneys, 22% in thigh muscles, and 18% in breast muscles. Amoxicillin residues were found 42% in liver, 30% in kidneys, 26% in thigh muscles and 22% in breast muscles. Most of the cases highest residues were found in liver such as tetracycline (48%), ciprofloxacin (44%), enrofloxacin (40%) and amoxicillin (42%) and almost lowest in breast muscles. In addition, nine positive samples from broiler were selected for amoxicillin residue quantification by UHPLC. It was observed that the concentration of amoxicillin residue in liver was ranging from 16.92 μg/kg to 152.62 μg/kg and in breast muscle was 45.38 μg/kg to 60.55 μg/kg, respectively. The maximum and minimum peak time was 4.7-5.2 min. Among the poultry tissues, liver had the highest level of antibiotic residues in comparison to other samples but the variation was not significant (p>0.05). Conclusions: Evidence suggests that more judicious use of antimicrobials in food animals will reduce the selection of resistant bacteria and help to preserve these valuable drugs for both human and veterinary medicine. The method described in this study is a simple, easy inexpensive which can be readily adopted by any laboratory for the detection of antibiotic residues in tissues of food-producing animals.

Comparison of Four Microbiological Inhibition Tests for the Screening of Antimicrobial Residues in the Tissues of Food-Producing Animals

The study compares two existing microbiological inhibition tests, Screening Test for Antibiotic Residues (STAR) and Premi®Test with two recently introduced tests, Nouws Antibiotic Test (NAT) and Total Antibiotics for the screening of antimicrobial residues in the tissues of food-producing animals. In the negative or positive sample classification based on inhibition of the growth of test strain sensitive to many antibiotics and sulphonamides, out of 142 samples obtained from slaughterhouses and retail operations, 39 samples yielded a positive result in one or more tests: 4 samples in four tests, 14 samples in three tests, 13 samples in two tests, and 8 samples in one test. As for the numbers of observed positive samples, the descending sequence of tests was: STAR, Total Antibiotics, Premi®Test, NAT. The growth inhibition was observed in three out of seven test strains, namely Bacillus cereus ATCC 11778, Kocuria rhizophila ATCC 9341, and Bacillus stearothermophilus var. calidolactis. Considering the test strains sensitivity and no inhibition on the Bacillus pumilus NCIMB 10822 NAT test plates, our preliminary conclusion is that the animal samples are suspected for the presence of tetracycline, macrolide, and β-lactam antibiotics.

Development and validation of an immunochromatographic assay for the rapid detection of quinoxaline-2-carboxylic acid, the major metabolite of carbadox in the edible tissues of pigs

A new method was developed for the determination of quinoxaline-2-carboxylic acid, the marker residue of carbadox, in the edible tissues of food-producing animals using a colloidal gold probe-based immunochromatographic assay. The highly specific polyclonal antibody (PcAb), which was very sensitive to N-butylquinoxaline-2-carboxylic acid (BQCA) with an IC50 value of 2.38 ng ml−1, was selected for the development of an immunochromatographic assay (ICA). Only 5 min were required to perform this assay; it had a visual detection limit of 25 ng g−1 for quinoxaline-2-carboxylic acid. The results of the analysis of quinoxaline-2-carboxylic acid in animal tissues using the immunochromatographic assay showed good agreement with those obtained by HPLC. In conclusion, the method was rapid and accurate for screening residues of carbadox in the edible tissues of food-producing animals.

Antibiotic Residues - A Global Health Hazard

Use of Antibiotic that might result in deposition of residues in meat, milk and eggs must not be permitted in food intended for human consumption. If use of antibiotics is necessary as in prevention and treatment of animal diseases, a withholding period must be observed until the residues are negligible or no longer detected. The use of antibiotics to bring about improved performance in growth and feed efficiency, to synchronize or control of reproductive cycle and breeding performance also often lead to harmful residual effects. Concern over antibiotic residues in food of animal origin occurs in two times; one which produces potential threat to direct toxicity in human, second is whether the low levels of antibiotic exposure would result in alteration of microflora, cause disease and the possible development of resistant strains which cause failure of antibiotic therapy in clinical situations. A withdrawal period is established to safeguard human from exposure of antibiotic added food. The withdrawal time is the time required for the residue of toxicological concern to reach safe concentration as defined by tolerance. It is the interval from the time an animal is removed from medication until permitted time of slaughter. Heavy responsibility is placed on the veterinarian and livestock producer to observe the period for a withdrawal of a drug prior to slaughter to assure that illegal concentration of drug residue in meat, milk and egg do not occur. Use of food additives may improve feed efficiency 17% in beef cattle, 10% in lambs, 15% in poultry and 15% in swine. But their indiscriminate use will produce toxicity in consumers. WHO and FAO establish tolerances for a drug, pesticide or other chemical in the relevant tissues of food producing animals. The tolerance is the tissue concentration below, which a marker residue for the drug or chemical must fall in the target tissue before that animal edible tissues are considered safe for human consumption. Tolerances are established based on extensive toxicological studies of potential hazards of consumption to human.

Development and validation of an HPLC confirmatory method for residue analysis of ten quinolones in tissues of various food‐producing animals, according to the European Union Decision 2002/657/EC

The aim of this work was to develop an HPLC method for the simultaneous determination of ten quinolones: enoxacin, ofloxacin, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, oxolinic acid, nalidixic acid, and flumequine, in various tissues of food-producing animals. Separation was achieved on a PerfectSil Target column (250 mm x 4 mm, ODS-3, 5 microm), by MZ-Analysentechnik (Germany), at room temperature. The mobile phase consisted of 0.1% TFA-CH(3)OH-CH(3)CN and was delivered by a gradient program of 35 min. The detection and quantitation was performed on a photodiode array detector at 275 and 255 nm. Caffeine (7.5 ng/microL) was used as the internal standard (IS). Analytes were isolated from tissue samples by 0.1% methanolic TFA solution. SPE, using LiChrolut RP-18 cartridges, was applied for further purification. The extraction protocol was optimized and the final recoveries varied between 92.0 and 107.4%. The method was fully validated according to Commission Decision 2002/657/EC. Limits of quantitation for the examined quinolones extracted from each tissue were much lower than the respective Maximum Residue Levels, ranging between 30 and 50 microg/kg for bovine tissue, between 30 and 55 microg/kg for ovine tissue, and between 40 and 50 microg/kg for porcine tissue.

An Analytical Method to Screen for Six Thyreostatic Drug Residues in the Thyroid Gland andMuscle Tissues of Food Producing Animals by Liquid Chromatography with Ultraviolet Absorption Detection and Liquid Chromatography/Mass Spectrometry

A method was developed and validated to screen for residues of the thyreostatic drugs, tapazole (TAP), mercaptobenzimidazole (MBI), thiouracil (TU), methylthiouracil (MTU), propylthiouracil (PrTU), and phenylthiouracil (PhTU) in bovine, equine, ovine, and porcine thyroid and muscle tissues at concentrations > or = 5 ng/g using 2-methoxy-mercaptobenzimidazole (MeMBI) and dimethylthiouracil (DMTU) as internal standards. In this method, the drugs were solvent extracted from thyroid and muscle tissue and cleaned up on an amino-propyl solid-phase extraction (SPE) cartridge. The unretained fraction containing TAP and MBI and the internal standard, MeMBI, was collected as Fraction 1. The retained fraction containing TU, MTU, PrTU, PhTU, and the internal standard, DMTU, was eluted with 3% acetic acid-isopropanol as Fraction 2. Fraction 1 was further cleaned up on an alumina B SPE cartridge and analyzed by gradient elution on a C18 high-performance liquid chromatography (HPLC) column with ultraviolet detection at wavelengths of 255 and 300 nm. Fraction 2 was taken to dryness, derivatized with 4-chloro-7-nitrobenzo-2-furazan at pH 8, and analyzed by gradient elution on a C18 LC column with mass spectrometry (MS) detection. Any "presumptive positive" test results were submitted for further analysis by LC/MS/MS. The validated method was applied to the analysis of over 300 thyroid tissue samples.

Monitoring Chlorinated Pesticides and Toxic Elements in Tissues of Food-Producing Animals in Yugoslavia

According to the established monitoring program in Yugoslavia, 941 swine, 561 cattle, and 358 lamb samples collected during a 5-year period were analyzed for chlorinated pesticide residues. Less than 10% of the examined samples contained residues of HCB (hexachlorobenzene), HCH (hexachlorocyclohexane), lindane (gamma-hexachlorocyclohexane), and total DDT (p,p'-DDT and metabolites) at concentrations greater than the lowest detectable limit. None of the swine and cattle samples exceeded the residue limit (RL). Among lamb samples, 2.5% contained lindane residues exceeding the RL, with a mean of 4.75 mg/kg. This finding suggests lindane's improper use as a veterinary pesticide, probably as a sheep-dip for destroying ectoparasites. During the same period, 849 swine, 584 cattle, and 350 lamb samples also were analyzed for toxic elements (Pb, Cd, Hg, and As). In the majority of samples, toxic elements were present at levels less than 50% of RLs. Only Cd and Pb RLs were exceeded in several cases. Differences in trace element contents of samples from different animals were not significant. The data indicate that residues in tissues of food-producing animals do not have a great potential impact on public health.

Liquid Chromatographic Assay of Tetracyclines in Tissues of Food-Producing Animals

A survey of the literature is presented on liquid chromatographic (LC) determination of tetracyclines in plasma, urine, and tissues of food-producing animals. Food Safety and Inspection Service (FSIS) research on tetracyclines during 1973-1984 is discussed, including the thin layer chromatographic qualitative identification method for tissues. Research on development of LC column packings for trace level chromatography of tetracyclines and anhydrotetracyclines is also discussed. Data are shown for recovery, ruggedness testing, and analyst qualification studies on the tentative version of the LC method.

Safety assessment of animal drugs

The Food and Drug Administration has published a proposal ( Chemical Compounds in Food-Producing Animals: Criteria and Procedures for Evaluating Assays for Carcinogenic Residues, Federal Register 44, 17070–17114 March 20 1979 ) to establish procedures and minimum criteria to ensure the absence of cancer-causing residues in edible products of food-producing animals to which drugs, food additives, or color additives have been administered. Section III of the proposed rule (termed the Sensitivity of the Method Document or SOM) would require that metabolism and comparative metabolism studies be conducted in target (food-producing) and test (laboratory) animals, respectively. As a practical matter, current agency policy prescribes that information from such studies would be required whether the compound was considered to be a suspect carcinogen or a noncarcinogen. Metabolism studies to determine what drug-derived residues may be present in the tissues of food-producing animals at a particular withdrawal time as well as comparative metabolism studies to determine the appropriateness of the laboratory animal as a test species, and the relationship of the two studies to each other, are discussed in terms of the procedures used for the human safety assessment of animal drugs.