What can we learn from past and recent Bavarian knowledge for the future development of European veterinary herbal medicine? An ethnoveterinary study.

ETHNOPHARMACOLOGICAL RELEVANCE: While the interest in finding medical solutions for the worldwide antibiotics crisis is rising, the legal possibility of simplified authorization of herbal veterinary medicinal products is dwindling. An important basis for both the preservation and development of knowledge in veterinary herbal medicine are pharmacological and clinical studies on the performance of herbal remedies, based on historical written sources on the treatment of farm animals with medicinal plants, as well as current ethnoveterinary research. Nevertheless, there is only limited systematic ethnoveterinary research in Europe, with the exceptions of the Mediterranean region, Switzerland and Austria. We conducted a survey on the ethnoveterinary knowledge of farmers in Bavaria, and analyzed two regional historical textbooks. AIM OF THE STUDY: We documented the local veterinary knowledge about livestock in Bavaria based upon local historical textbooks and upon ethnoveterinary interviews to discover opportunities for the future development of European veterinary herbal medicine. MATERIAL AND METHODS: In 2018/2019 we conducted 77 semi-structured interviews with 101 farmers from different types of farms. Detailed information about homemade herbal remedies (plant species, plant part, manufacturing process, source of knowledge) and the corresponding use reports (target animal species, category of use, route of administration, dosage, source of knowledge, frequency of use, last time of use and farmers' satisfaction) were collected. To compare our data with the literature, the use reports of two local historical textbooks were analyzed and compared with the data from the interviews. RESULTS: 716 homemade remedy reports (HRs) for altogether 884 use reports (URs) were documented in this study. We picked the 363 HRs that consisted of a single plant species with or without other natural products (HSHRs) for a deeper analysis. These HSHRs were prepared from 108 plant species that belonged to 57 botanical families. The most URs were documented for the families of: Asteraceae, Linaceae and Urticaceae. Calendula officinalis L. (Asteraceae), Linum usitatissimum L. (Linaceae) and Urtica dioica L. (Urticaceae) were the most often documented single species. A total of 448 URs were gathered for the 363 HSHRs. The largest number of URs was for treatments of gastrointestinal disorders and metabolic dysfunctions, followed by skin alterations and sores. For nearly half of the URs the source of knowledge was family and friends. For 80 URs the source of knowledge was different from that of the corresponding HSHRs. For 68% of the URs farmers mentioned at least one use during the last 5 years. Half of the plant species that were mentioned in the historical literature were also mentioned in URs by the interviewees. CONCLUSION: In Bavaria, medicinal plants are actively used by farmers to treat their livestock with a high level of satisfaction. The knowledge is not passed on from generation to generation in a purely static way, but is dynamically developed by the users in almost one fifth of the URs. Ethnoveterinary research combined with data from regional historical textbooks may facilitate pharmacological and clinical studies in veterinary medicine, and the discussion about a simplified registration for traditional herbal veterinary medicinal products.

Development of a modified quick, easy, cheap, effective, rugged, and safe method based on melamine sponge for multi-residue analysis of veterinary drugs in milks by ultra-performance liquid chromatography tandem mass spectrometry.

The purpose of this study was to develop a modified QuEChERS method based on melamine sponge for rapid determination of multi-class veterinary drugs in milks by UPLC-MS/MS. Through simple infiltration and extrusion, fast and convenient matrix purification could be achieved within several seconds, and there was no need of extra phase separation operations. Good linearity with correlation coefficient (R2) ≥0.999 was obtained for all drugs in the range of 2~500 µg·kg-1. The obtained matrix effects were within ±20% for all monitored drugs. The recoveries of all monitored drugs ranged from 60.7% to 116.0% at three spiked levels (50, 100, and 200 µg·kg-1), with relative standard deviations less than 7.4%. Comparatively low LODs and LOQs were obtained in the ranges of 0.1~3.8 µg·kg-1 and 0.2~6.3 µg·kg-1, respectively. Compared with conventional purification adsorbents, melamine sponge yielded an equal or higher purification performance with matrix removal rate as high as 52.5% and acceptable recoveries in range of 60%-120% for all monitored drugs. The satisfactory results have demonstrated the good potential of melamine sponge in matrix purification for rapid determination of multiclass residues in food safety.

Bioactive Compounds from Marine Sponges: Fundamentals and Applications.

Marine sponges are sessile invertebrates that can be found in temperate, polar and tropical regions. They are known to be major contributors of bioactive compounds, which are discovered in and extracted from the marine environment. The compounds extracted from these sponges are known to exhibit various bioactivities, such as antimicrobial, antitumor and general cytotoxicity. For example, various compounds isolated from Theonella swinhoei have showcased various bioactivities, such as those that are antibacterial, antiviral and antifungal. In this review, we discuss bioactive compounds that have been identified from marine sponges that showcase the ability to act as antibacterial, antiviral, anti-malarial and antifungal agents against human pathogens and fish pathogens in the aquaculture industry. Moreover, the application of such compounds as antimicrobial agents in other veterinary commodities, such as poultry, cattle farming and domesticated cats, is discussed, along with a brief discussion regarding the mode of action of these compounds on the targeted sites in various pathogens. The bioactivity of the compounds discussed in this review is focused mainly on compounds that have been identified between 2000 and 2020 and includes the novel compounds discovered from 2018 to 2021.

Development and validation of a multi-residue analytical method for veterinarian and human pharmaceuticals in livestock urine and blood using UHPLC-QTOF.

The aim of this work is to contribute to the assessment of multi-residue analysis of veterinarian and human pharmaceuticals using UHPLC-QTOF in livestock urine and blood (cattle, chicken, sheep and pig). Firstly, an in-house database including compound name, monoisotopic mass, chemical formula, retention time, chemical structure, and three CID MS-MS spectra of the 234 selected drugs were built for qualitative detection. Secondly, the method validation result showed that all the 234 drugs exhibited good linearity with determination coefficients (R2) higher than 0.999. Then, the distribution of the drugs recoveries, intra-day RSD and inter-day RSD results for all seven matrices were tested. Finally, after a carefully cross check, 150 veterinarian and human pharmaceuticals could meet the methodological requirements (recovery, 50-120%; intra-day RSD ≤ 15%, inter-day RSD ≤ 20%) in all seven matrices. Our results suggested that although the main applications of UHPLC-QTOF are directed towards detection and identification of the compounds, this method should be also applied for quantitative purposes.

A systematic review on the ethnoveterinary uses of mediterranean salt-tolerant plants: Exploring its potential use as fodder, nutraceuticals or phytotherapeutics in ruminant production.

ETHNOPHARMACOLOGICAL RELEVANCE: Salt-tolerant plants are well adapted to the harsh conditions of the Mediterranean region, where have been used traditionally as food and medicines for human and animals. In addition, various species are currently recognized as sources of metabolites with pharmacological, cosmetical and nutraceutical interest. Nevertheless, ethnoveterinary data on salt-tolerant plants are dispersed in the literature and there are few discussions on its veterinary potential. Having in mind the rising interest on organic farming, alternatives to chemical substances in livestock production and concern for animal health and welfare practices, these plants may represent an untapped resource for animal management and veterinary purposes. In this sense, the purpose of this work is to summarize the ethnoveterinary knowledge on salt-tolerant plants described in the Mediterranean region, raising awareness to the potential of this group of plants to be used in veterinary science, targeting especially ruminants. MATERIAL AND METHODS: Literature search (2000-2020) was conducted using Web of Science and Science Direct databases. Ethnoveterinary reports (EVR) concerning salt-tolerant plants were summarized and filtered for ruminants. From the final 29 publications, EVR concerning therapeutic uses were categorized according to its ATCvet code and results analyzed. RESULTS: A total of 221 EVR were identified from 39 plants, belonging to 21 plant families, targetting ruminants. Ten EVR (4.5%) concerned uses of salt-tolerant species as animal feed, while around 75% of therapeutic uses was represented by three categories: alimentary tract and metabolism (QA; n = 75), dermatologicals (QD; n = 53) and genitourinary system and sex hormones (QG; n = 41). Pistacia lentiscus L., Foeniculum vulgare Mill., Dittrichia viscosa (L.) Greuter, Plantago major L. and Hordeum vulgare L. were the most cited species in the latter categories. CONCLUSIONS: The ethnoveterinary knowledge on salt-tolerant species hints some plants of veterinary pharmacological potential, but other species deserve further notice. This information should serve as a basis and, coupled with the currently available scientific data on bioactive properties and chemical composition of salt-tolerant species, inspire additional research on the exploitation of this botanical group, as sources of novel products for ruminant nutrition, health and quality of its products.

Multiclass, Multiresidue Method for the Quantification and Confirmation of 112 Veterinary Drugs in Game Meat (Bison, Deer, Elk, and Rabbit) by Rapid Polarity Switching Liquid Chromatography-Tandem Mass Spectrometry.

An analytical program for multiclass, multiresidue residue analysis to qualitatively and quantitatively determine veterinary drug compounds in game meats by LC-MS/MS has been developed and validated. The method was validated for the analysis of muscle from bison, deer, elk, and rabbit to test for 112 veterinary drug residues from the following drug classes: ß-agonists, anthelmintics, anti-inflammatory drugs, corticosteroids, fluoroquinolones, ß-lactams, macrolides, nitroimidazoles, phenicols, polypeptides, sulfonamides, tetracyclines, thyreostats, and tranquilizers. Muscle was extracted using a simple and quick procedure based on a solvent extraction with 80% ACN/water and sample cleanup with dispersive solid-phase extraction. The compounds of interest were separated using a Waters HSS T3 column and detected by tandem mass spectrometry with rapid polarity switching to detect both negatively and positively charged ions in a single run. Recoveries were calculated using extracted matrix-matched calibration curves for each type of matrix. The average accuracy of fortified compounds ranged from 95.6 to 101% at the target quantitative validation level in the four matrices. The method was also validated as a qualitative screening method where all sample responses were compared with a single extracted matrix-matched calibrant at the target testing level (5 or 25 ng/g). Samples demonstrating a presumptive positive above the threshold value were re-extracted and analyzed with a five-point matrix-matching extracted calibration curve. Since the beginning of this survey program, 360 samples have been analyzed for veterinary drug residues in game meats. Antibiotic or tranquilizer residues have been identified in deer (chlortetracycline, haloperidol, and tulathromycin) and rabbit (sulfadiazine).

High-Throughput Mega-Method for the Analysis of Pesticides, Veterinary Drugs, and Environmental Contaminants by Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry and Robotic Mini-Solid-Phase Extraction Cleanup + Low-Pressure Gas Chromatography-Tandem Mass Spectrometry, Part 1: Beef.

In this work, a new mega-method of sample preparation called "QuEChERSER" (more than QuEChERS) is being presented for the first time. Fast, efficient, and cost-effective analysis of chemical contaminants in meat is useful for international trade, domestic monitoring, risk assessment, and other purposes. The goal of this study was to develop and validate a simple high-throughput mega-method for residual analysis of 161 pesticides, 63 veterinary drugs, 24 metabolites, and 14 legacy environmental contaminants (polychlorinated biphenyls) in bovine muscle for implementation in routine laboratory analyses. Sample preparation of 2 g test portions entailed QuEChERS-based extraction with 10 mL of 4:1 (v/v) acetonitrile/water, and then 204 µL was taken, diluted, and ultracentrifuged prior to analysis of veterinary drugs and pesticides by ultra-high-performance liquid chromatography-tandem mass spectrometry. The remaining extract was salted out with 4:1 (w/w) anhydrous MgSO4/NaCl, and 1 mL was transferred to an autosampler vial for automated mini-cartridge solid-phase extraction (Instrument Top Sample Preparation) cleanup with immediate injection using fast low-pressure gas chromatography-tandem mass spectrometry analysis. The automated cleanup and both instruments were all operated in parallel in 13-15 min cycle times per sample. Method validation according to United States Department of Agriculture requirements demonstrated that 221 (85%) of the 259 analytes gave average recovery between 70 and 120% and interday relative standard deviation of ≤25%. Analysis of a certified reference material for veterinary drugs in freeze-dried bovine muscle was also very accurate, further demonstrating that the QuEChERSER mega-method can be implemented to save time, labor, and resources compared to current practices to use multiple methods to cover the same analytical scope.

High-Throughput Mega-Method for the Analysis of Pesticides, Veterinary Drugs, and Environmental Contaminants by Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry and Robotic Mini-Solid-Phase Extraction Cleanup + Low-Pressure Gas Chromatography-Tandem Mass Spectrometry, Part 2: Catfish.

The goal of this study was to develop and validate a new method for simultaneous determination of 106 veterinary drugs and 227 pesticides and their metabolites plus 16 polychlorinated biphenyls (PCBs) at and below their regulatory levels established for catfish muscle in the European Union and U.S.A. To do this, two different QuEChERS-based methods for veterinary drugs and pesticides and PCBs were modified and merged into a single mega-method dubbed "QuEChERSER" (more than QuEChERS), which is presented here for the first time. The mega-method was validated in catfish at four different spiking levels with 10 replicates per level. Sample extraction of 2 g test portions was made with 10 mL of 4:1 (v/v) acetonitrile/water, and then an aliquot was taken for ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis of 106 veterinary drugs and 125 pesticides, including metabolites. The remaining extract after salting out was subjected to automated mini-solid-phase extraction cleanup (Instrument Top Sample Preparation) for immediate injection in low-pressure gas chromatography-tandem mass spectrometry (LPGC-MS/MS). The cleanup was conducted in parallel with the 10 min LPGC-MS/MS analysis for 167 PCBs, pesticides, and metabolites, which was conducted in parallel with the 10 min UHPLC-MS/MS analysis for 231 analytes to increase sample throughput (49 analytes were included in both techniques). In MS/MS, three ion transitions were monitored for nearly all targeted analytes to provide unambiguous identification as well as quantification. Satisfactory recoveries (70-120%) and relative standard deviations of ≤20% were achieved for 98 (92%) of the veterinary drugs and their metabolites and for 222 (91%) of pesticides, metabolites, and PCBs, demonstrating that the developed method is applicable for the analysis of these contaminants in fish as part of regulatory monitoring programs and other purposes.

Simultaneous extraction and determination of 45 veterinary antibiotics in swine manure by liquid chromatography-tandem mass spectrometry.

A multiresidue method for identification and quantification of 45 veterinary antibiotics (VAs) belonging to 5 different drug classes has been developed, which is the first comprehensive method for pig manure. The proposed method used mixed liquor with methanol: acetonitrile: citrate buffer ratio of 1:1:2 to extract the target VAs from freeze-dried manure. The extracting solution passed through solid-phase extraction (SPE) procedure with Oasis HLB cartridges, which could isolate the target VAs and clean the samples in a single step. After blow-drying and concentrating, the samples were analyzed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in one single injection with a run time of 12 min. The average recovery rates for most of the VAs were in the range of 50-120% with relative standard deviations below 15%. Linearity was studied in the range between 2 and 1000 µg/kg using matrix-matched calibration and pure solvent calibration, to evaluate the matrix effects (MEs). The limits of detection (LDs) and quantification (LQs) were in the range of 0.01-1.54 µg/kg and 0.03-5.13 µg/kg respectively, except for penicillin G. Finally, the proposed method was used to quantify VA residues in real swine manure from three farms with different scales; tetracyclines, sulfonamides, quinolones and macrolides were the most frequently detected compounds.

Determination of 62 veterinary drugs in feedingstuffs by novel pressurized liquid extraction methods and LC-MS/MS.

A fast and simple method for the determination of 62 veterinary drugs in feedingstuffs was developed, optimized, validated, and applied to real samples. Sample preparation was based on a pressurized liquid extraction method using a hard cap coffee machine, which was compared to a commercial pressurized liquid extraction system. Extraction was performed with diatomaceous earth, acetonitrile (20%), and formic acid (0.1%). A central composite design was used to optimize the composition of the extraction solvent. The extracts were analyzed using two chromatographic modes (reversed phase with C18 and HILIC). Analytical limits were set to 25 (limit of detection) and 75 µg kg-1 (limit of quantitation). For banned substances, a salting-out step was included, achieving LOQ lower as 1 µg kg-1 for ractopamine. Other figures of merit such as precision, trueness, decision limit (CCα), method capability (CCß), matrix effects, stability, recovery, and measurement uncertainty were also reported for analytical validation. The method was successfully applied to hundreds of real samples demonstrating its fitness-for-purpose for the analysis of sulfonamides, tetracyclines, fluoroquinolones, avermectins, quinolones, beta-agonists, beta-lactams, amphenicols, benzimidazoles, coccidiostats, lincosamides, macrolides, nitrofurans, quinoxalines, melamine, and trimethoprim.

Detection of azithromycin residue in broiler feathers by liquid chromatography-tandem mass spectrometry.

In the study, a sensitive and reproducible method for the quantitative analysis of azithromycin in broiler feather samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. Feather samples were rinsed after being wrapped in medical gauze, then chopped and then added to 5% (v/v) ammonia in methanol solution for ultrasonic extraction. The extract was purified by the combination of commercial polymeric microparticles (Oasis MCX) and Fe3O4 nanoparticles. The LC separation was performed on an Agilent Eclipse plus C18 column. Multiple reaction monitoring was used for the selective detection of azithromycin. The good linearity curve of azithromycin in feather sample was in the range from 1.0 µg kg-1 to 100.0 µg kg-1 with 0.9935 of correlation coefficient. And the limit detection and limit of quantification was 0.5 µg kg-1 and 2.0 µg kg-1 in spiked feather samples. The recoveries of azithromycin were 85.2-94.7% with the relative standard deviation less than 10%. The established method is simple, rapid, sensitive and specific, and could meet the need of government and enterprises to monitor the illegal use of azithromycin in livestock and poultry breeding.

Plant and natural product based homemade remedies for veterinary uses by the Peul community in Benin.

ETHNOPHARMACOLOGICAL RELEVANCE: Across Africa, Peul community typically rely on plant-based veterinary knowledge to manage common livestock health problems. Unfortunately, their nomadic life-style being affected by conflicts, land tenure constraints, and drought, they have been shifting to a sedentary life. The process of their settlement led to the erosion of the vast ethnoveterinary skills they had acquired over centuries and forced them to replace the plant and other species they used by commercial products. AIM OF THE STUDY: 1) To collect comprehensive data from the Benin Peul community on common plant-based remedies used to treat livestock diseases and document their preparation and administration. 2) To evaluate the differences and consensus among the Peul community across ecological regions in Benin. MATERIALS AND METHODS: We conducted semi-structured interviews among 88 Peul camps, three (03) bioclimatic zones, and 225 transhumant dialog partners, including agro-pastoralists, healers and pastoralists from mid-July to end of December 2015. Detailed information about homemade herbal remedies (plant species, plant part, manufacturing process) and the corresponding use reports (target animal species, category of use and route of administration) was collected. RESULTS: A total of 418 homemade remedies were reported, of which 235 involved only one plant species (Homemade Single Species Herbal Remedy Reports; HSHR). Information on a total of 310 use reports (UR) were mentioned for the 235 HSHR, and they included 116 plant species belonging to 39 botanical families. Among them, 229 UR were indicated for cattle, 43 UR for poultry, and 38 UR for sheep and goats. The most cited plant species were Khaya senegalensis (19 HSHR; 8.08%), Parkia biglobosa (14 HSHR; 5.95%), Euphorbia unispina (11 HSHR; 4.68%), and Anogeissus leiocarpus (6 HSHR; 2.55%). The URs were indicated for the treatment of viral, parasitic and bacterial diseases but also for multifactorial disorders like diarrhoea, fever, threatened abortion, agalactia etc. The number of plants referred to HSHR decreased from Sudanian to Guineo-congolian zones in concordance with the presence of Peuls. CONCLUSION: The Peul community holds a huge ethnoveterinary knowledge, which needs to be documented, valorised, and promoted. It appears vital to assess phytochemical and pharmacological properties of the most reported species, and their availability across the ecological zones in order to ensure their sustainable use and before this indigenous knowledge disappears completely.

Multiclass and multiresidue screening of veterinary drugs and pesticides in infant formula using Quadrupole-Orbitrap MS with PRM scan mode.

A multiclass and multiresidue method for screening veterinary drugs and pesticides in infant formula was developed and validated using ultrahigh-performance liquid chromatography coupled to Quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-HRMS). A total of 49 veterinary drugs and pesticides investigated belong to 11 classes including antivirals, anticoccidials, macrolides, pyrethroids, insecticides, sulfonamides, beta-agonists, sedatives, thyreostats, nonsteroidal anti-inflammatory drugs, and other pharmacologically active substances. A generic sample preparation and highly selective acquisition mode of parallel reaction monitoring (PRM) were deliberately incorporated to perform efficient screening analysis. As a result, the screening target concentrations of the analytes varied from 1 to 500 µg/kg with ≤5% of false compliant rate as specified in Decision 2002/657/EC for screening analysis. The average recoveries ranged from 40.7 to 124.9% as well as the relative standard deviations from 4.2 to 26.6%, respectively. The matrix effects and interferences were effectively controlled by integrated application of dispersive solid phase extraction, PRM scan mode, and matrix-matched standard calibration. The proposed method will be helpful to provide applicable strategy for screening residues in infant formula with surveillance purpose.

Determination of veterinary drug/pesticide residues in livestock and poultry excrement using selective accelerated solvent extraction and magnetic material purification combined with ultra-high-performance liquid chromatography-tandem mass spectrometry.

An ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method based on selective accelerated solvent extraction and magnetic material purification was established to analyze the residues of various veterinary antibiotics and agricultural fungicides and insecticides in livestock and poultry excrement. Methanol-acetonitrile (4:1, V/V) was used as the extraction solvent and static extraction was conducted three times in 5 min. Preliminary purification was achieved by adding 0.5 g acidic alumina-florisil (1:1, W/W) to the extraction cell while the extraction was conducted. This preliminarily-purified extract was further purified using magnetic material, then analyzed using UPLC-MS/MS. Under optimal conditions, 33 types of antibiotics, including 3 amphenicols, 8 macrolides, 17 sulfonamides and 5 nitroimidazoles, as well as 37 types of pesticides, including 27 insecticides and 10 fungicides, were detected. Recoveries ranged from 60.3% to 110.0% at three spiked concentrations (10 µg/kg, 20 µg/kg and 50 µg/kg), the detection limits ranged from 0.2 to 3.5 µg/kg and the quantitative limits ranged from 0.5 to 11.5 µg/kg. This newly-established method was tested using 30 livestock and poultry excrement samples and confirmed its use for determining veterinary drugs and pesticides in practical samples.

Restricted access magnetic imprinted microspheres for directly selective extraction of tetracycline veterinary drugs from complex samples.

A novel restricted access media-magnetic molecularly imprinted polymers (RAM-MMIPs) was prepared as magnetic-solid phase extraction (M-SPE) material for tetracyclines (TCs). The RAM-MMIPs can not only specifically adsorb target molecules in samples, but also effectively eliminate the interference of protein macromolecules. The protein exclusion rate is 99.4%. Besides, RAM-MMIPs have a uniform imprinted and hydrophilic layer (600 nm), rapid binding kinetic (35 min), high selectivity and larger adsorption capacity. The M-SPE was coupled with HPLC/UV to extract TCs from untreated milk and egg samples, and several major factors affecting M-SPE efficiency were optimized. Under optimized conditions, the developed method achieved good linearity (R2>0.9989), lower limits of detection (LOD) and higher recoveries of TCs. For milk samples, the LOD is 1.03-1.31 µg L-1 and the recovery is 86.7% to 98.6% with relative standard deviation (RSD) of 1.4-5.7%. For the egg samples, the LOD, recovery and RSD are 2.21-2.67 µg L-1, 84.2-96.5% and 1.7-5.9%, respectively. Consequently, this work provides an improved strategy for the selective extraction and detection of target molecules directly from complex samples with proteins.

Comparison of Solid-Phase Microextraction to Solvent Extraction and QuEChERS for Quantitative Analysis of Veterinary Drug Residues in Chicken and Beef Matrices.

A fully automated high-throughput method using solid-phase microextraction (SPME) was developed and validated for quantitative analysis of more than 100 veterinary drugs in chicken and beef tissue. The work also encompassed a comparison of the SPME method to two well-documented sample preparation procedures, solvent extraction (SE) and quick, easy, cheap, effective, rugged, and safe (QuEChERS). SPME showed considerably less matrix effects, with only two compounds showing significant matrix effects in comparison to 30% of analytes in QuEChERS and 42% in SE in beef tissue. Excellent accuracy and precision results were achieved with all methods in the chicken matrix, with more than 91% of analytes falling within the 70-120% range of their true concentrations and relative standard deviation of ≤25% at 0.75X and 1.5X, where X is the maximum residue level. Similar results were achieved in beef tissue. All methods were able to meet regulatory limit of quantitation levels for the majority of target analytes.

Rapid simultaneous determination of 160 drugs in urine and blood of livestock and poultry by ultra-high-performance liquid chromatography-tandem mass spectrometry.

In order to address the specific question of food safety in livestock and poultry, it is imperative to monitor veterinary drugs at every moment in the process of livestock and poultry breeding. Thus, multi-residue analysis of a wide variety of drugs using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) has become a tool of critical significance, especially for veterinary drug monitoring programs. A total of 160 compounds, belonging to 17 different families of veterinary drugs, were investigated in the urine and blood of livestock and poultry. Drug samples were extracted using a slightly acidic acetonitrile solution. The QuEChERS (quick, easy, cheap, effective, rugged, and safe) preparation method, combined with dispersive solid phase extraction (d-SPE) was compared with the approach of solid phase extraction (SPE). In the end, the QuEChERS extraction procedure was selected to reduce matrix effects and efficiently extract target veterinary drugs, and d-SPE was applied as a cleanup step. Electrospray ionization coupled with positive dynamic multiple reaction monitoring (dMRM) was utilized for the analysis of 160 different drugs in a single chromatographic run of 24 min. The efficiency of this method was evaluated using 7 matrices (pig blood, cattle blood, sheep blood, chicken blood, pig urine, cattle urine, and sheep urine). Good linearity was obtained for the analytes in a concentration range of 1-100 ng/mL, with correlation coefficients higher than 0.990. Most of the 160 drugs studied gave estimated limits of detection (LOQs) of 1 ng/mL, with some LOQs reaching as much as 5 ng/mL. The mean recoveries at four spike-in levels of 1, 5, 10, and 50 ng/mL, ranged from 60% to 120%. The intra-day precision measurements had coefficients of variation (n = 6) <15%, and the inter-day precision measurements were below 25%. Our method was applied in real samples and proved to be adequate for routine analysis. The proposed method proved to be simple, rapid and reliable for monitoring 160 drugs in the urine and blood of livestock and poultry, and can also be used for food safety monitoring.

Ultra-high-performance liquid chromatography coupled to quadrupole orbitrap high-resolution mass spectrometry for multi-residue screening of pesticides, (veterinary) drugs and mycotoxins in edible insects.

A generic extraction and UHPLC-Q-Orbitrap™-HRMS method was developed for four insect species (mealworm, grasshopper, house cricket and black soldier fly) analyzing a large spectrum of organic chemical contaminants, including pesticides (n = 25), (veterinary) drugs (n = 29), and mycotoxins (n = 23). To prove the method as 'fit-for-purpose', a successful validation was performed, both qualitatively, by determining the screening detection limit (SDL), selectivity and specificity, as well as semi-quantitatively, by assessing the within-day precision (relative standard deviation (RSD)) and recovery. For both the mealworm, grasshopper, house cricket and black soldier fly, 64, 61, 59 and 62 compounds were detected at the respective SDL levels (1-100 µg kg-1), predominantly below existing maximum residue limits for other edible matrices. Mean recoveries ranged between 70% and 120% and RSD-values were in line with European regulations (CD 2002/657/EC; SANCO). Finally, the potential of the screening methodology was demonstrated on real insect samples, revealing minor to no contamination.

A new extraction procedure to abate the burden of non-extractable antibiotic residues in manure.

Through agricultural soil fertilization using organic manure, antibiotic residues can accumulate in the environment. In order to assess the risks of environmental pollution by veterinary drugs, monitoring of manure for antibiotic residues is necessary. As manure is a complex matrix, extraction of antibiotics proved to be challenging. In this study, 24 extraction solvents were assessed for the extraction of residues from manure representing ten antibiotics from the antibiotic classes tetracyclines, quinolones, macrolides, lincosamides and sulfonamides. Especially for the tetracyclines and quinolones the extraction solvent selection is critical, due to high fractions of non-extractable residues especially when using aqueous solvents (62-77% and 90-95% respectively when using milli-Q water). In contrast, sulfonamides can effectively be extracted with aqueous solvents. Overall, 0.125% trifluoroacetic acid in acetonitrile in combination with McIlvain-EDTA buffer proved to be the most effective extraction solvent. A longitudinal study pointed out that most antibiotics bind to solid manure particles instantaneously after addition. Trimethoprim is an exception, but because by using the optimal extraction solvent, the optimum fraction of bound residues is desorbed, this does not hamper quantitative analysis when using spiked manure quality control samples. Based on these new insights, the current in-house multi-residue LC-MS/MS method for manure analysis, containing 48 antibiotics, was revised, additionally validated and applied to 34 incurred manure samples.

Application of the Mechanical High-Pressure Method Combined with High-Performance Liquid Chromatography-Tandem Mass Spectrometry for Determination of Veterinary Drug Residues in Incurred Chicken and Rabbit Muscle Tissues.

Rapid sample preparation is a key step in the field of food safety. A mechanical high-pressure method using a laboratory-made meat press machine was first introduced in this study to process the incurred muscle samples of chicken and rabbit. By applying high pressure to animal muscle, the meat juice was obtained. After extraction and purification, veterinary drug residues in the juice were qualitatively and quantitatively analyzed by using high-performance liquid chromatography-tandem mass spectrometry. The sample press conditions and extraction solvents were optimized. Under the optimal conditions, all veterinary drug residues, including tetracycline, enrofloxacin, clenbuterol, ampicillin, lincomycin, erythromycin, and sulfadiazine, in the incurred samples were detected. The residual concentration of drugs in samples obtained by using the mechanical high-pressure method can reach up to 94.0% of that obtained by using the common homogenization method, suggesting that drug residues exist in the tissue juice, which justifies the use of the mechanical high-pressure method. Moreover, with the mechanical high-pressure method, the sample preparation time was shortened by five times, and the consumption of the extraction solvent was reduced by 50%, relative to the homogenization method.