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As milk should be free from harmful substances before leaving the farm, this study provides the results of the analysis of the presence of β-lactam and tetracycline residues and Aflatoxin M1 (AFM1) in milk samples obtained within one year from Ireland and Slovakia. To evaluate the presence of β-lactam and tetracycline residues, Duplex BT Scan assay, produced by Zeulab S. L. was used. For the detection of AFM1, AflaM1 Scan (Zeulab S. L.) tests were used. Of a total of 69 raw cow’s milk samples analysed, 40 samples were obtained from the farms in Slovakia and 29 samples from the farms in Ireland. Among the 69 analysed samples, 17 (24.6 %) samples were tested positive for the presence of β-lactam residues, 12 (17.4 %) samples for tetracycline residues and 59 (88.4 %) samples for AFM1. Milk samples positive for antibiotic residues and mycotoxins were not acceptable and it is important that the reputation of milk as a healthy and safe food is protected worldwide. Dairy farmers and consumers want to be confident that milk and milk products are of high quality and free of all pharmacologically active substances and toxins.

Milk used for human consumption must comply with the European Union legislative requirements for residues of inhibitory substances in milk, the values of which must not exceed the established maximum residue limit. In order to ensure the quality and safety of milk and milk products placed on the market, the presence of residues of inhibitory substances should be monitored and verified. The aim of our study was to select the most reliable method for the analysis of residues of inhibitory substances in milk. In the search for the most reliable method, a total of 49 milk samples were tested in the form of raw milk, skimmed milk and skimmed-milk powder throughout the agri-food chain. For comparison, the microbial inhibition tests Eclipse 50, Eclipse Farm, Explorer 2.0, Delvotest®, Premi®Test and the fast receptor screening test TwinSensor were used. The most relevant results were obtained by the Eclipse 50 and Eclipse Farm tests, the reliability of which were also confirmed by the Explorer 2.0 and Premi®Test tests. Moreover, according to the State Veterinary and Food Administration of the Slovak Republic, Eclipse 50 is an official reference method for the determination of residues of inhibitory substances in milk. Therefore, we can only state that of all the methods used, the Eclipse 50 seems to be the most reliable for routine control analysis of residues of inhibitory substances in all types of milk.

The objective of this study was to use the “Screening test for antibiotic residues” (STAR) as a broad-spectrum detection method for antibiotic residues in poultry meat. The STAR method is a microbiological inhibition assay (a five plate test) where the development of inhibition zones (IZs) indicates the presence of antibiotic residues in meat samples. By using the STAR method, in a total of 13 poultry products providing 18 meat samples (14 muscle and 4 skin) and 18 corresponding juice samples, 11 out of the 18 samples were positive for containing antibiotic residues. Based on muscle alone (which is the matrix validated for use in the STAR method), 6 of the 14 muscle samples were positive for antibiotic residues. The STAR method as a screening technique proves advantageous as it is relatively easy to perform and of a low cost. Furthermore, the STAR method not only indicates the presence or absence of antibacterial substances, but simultaneously, a positive sample gives an indication of the antibiotic family present due to the use of five different bacterial test organisms. Families of antibiotics pre-identified due to positive samples in the results of this study include aminoglycosides (one out of 18), beta-lactams and sulphonamides (6 out of 18), and macrolides (5 out of 18). Such pre-identification of the antimicrobial families allows for a targeted confirmatory analysis. However, one could argue that the STAR method is laborious and time consuming. Overall, given the potential for false positive/negative results, further confirmatory method analysis of the samples must be performed to ensure that the results and conclusions drawn here are true.

Eggs belong to the most frequently consumed products of animal origin worldwide, and therefore the safety of eggs is a substantiated issue. Conventional poultry rearing involves the use of antimicrobials added to their feed or potable water particularly for disease treatment, however, in some countries also for the prevention of diseases, promotion of growth and better utilisation of the feed. Thus, effective control of residues of such substances in eggs is very important for the protection of the public health. The aim of this study was to detect the potential presence of antimicrobial residues in fresh hen eggs using commercially available rapid screening methods (Premi®Test and EXP Ampulle test) and compare the results of both of these tests. We examined 22 samples randomly selected from among 66 samples purchased in 11 European countries. We respected the procedures as supplied by the manufacturers of the tests together with their respective test kits. The examination of eggs by the Premi®Test did not detect the presence of antimicrobial residues in the samples, while the EXP Ampulle test provided 8 positive and 6 dubious results. Our results allowed us to conclude that the EXP Ampulle appears to be more sensitive and allows one to carry out more effective control of the presence of antimicrobial residues in hen eggs intended for human consumption.

Undesirable substances enter the organism of animals mostly via feed, water or veterinary medicines and their residues pass subsequently into the products of animal origin. In dairy cows, sheep and goats these residues are eliminated particularly in milk. Milk intended for human consumption must comply with safety criteria also with respect to residues of antibiotics. The aim of this study was to determine the presence or absence of antibiotic residues in the milk using the tests Milchtest and Premi®Test. While the Milchtest was developed for the determination of antibiotic residues in cow, sheep and goat milk, the Premi®Test is intended for the determination of antibiotic residues in meat juice, liver, kidneys, fish, eggs and in the urine of animals treated with antibiotics. As examined matrices, we used 45 samples of raw cow’s milk collected at 3 agricultural farms and 10 samples of milk offered to consumers at grocery stores. When using the Milchtest, 8 samples tested positive and 10 provided dubious results while testing with the Premi®Test showed that only 6 samples were positive for antibiotics. Comparison of the results confirmed a higher detection sensitivity of Milchtest reflected in higher numbers of positive samples and the detection of dubious results in samples of raw cow’s milk. However, it should be noted that even the Premi®Test, although not intended preferably for the determination of antibiotics in milk, can be used, if needed, for the preliminary screening of antibiotic residues in such a matrix.

The Total Antibiotics test is a microbial inhibition test which has been recently introduced for the detection of antibiotics in meat. The aim of this study was to determine whether it would be suitable for the detection of coccidiostats in poultry meat. A comparison with the Premi®Test was assessed also for the suitability of the detection of coccidiostats in poultry meat. A selection of poultry meat samples of different organ parts were assessed with 14 samples from Slovakian farms that had previously been tested for coccidiostats by the Veterinary and Food Institute in Košice. In addition, another 8 samples from varied Slovakian supermarkets such as Lidl, Billa and Tesco with samples of chicken or duck meat, were tested. Each prepared sample was added to the Total Antibiotics kit tubes and incubated. The samples from all sources showed a mixture of positive and negative results for the detection of coccidiostats.

Silver(I) complexes with proline and hydroxyproline were synthesized and structurally characterized and crystal structure analysis shows that the formulas of the compounds are {[Ag 2 (Pro) 2 (NO 3 )]NO 3 } n (AgPro) (Pro = L-proline) and {[Ag 2 (Hyp) 2 (NO 3 )]NO 3 } n (AgHyp) (Hyp = trans -4-hydroxy-L-proline). Both complexes crystallize in the monoclinic lattice with space group P 2 1 with a carboxylate bidentate-bridging coordination mode of the organic ligands Pro and Hyp (with NH 2 + and COO - ) geometry around one silver(I) ion with 2v ) geometry around one silver(I) ion with τ 4 values of 58% (AgPro) and 51% (AgHyp). Moreover, the results of spectral and thermal analyses correlate with the structural ones. 1 H and 13 C NMR spectra confirm the complexes species' presence in the DMSO biological testing medium and their stability in the time range of the bioassays. In addition, molar conductivity measurements indicate complexes' behaviour like 1 : 1 electrolytes. Both complexes showed higher or the same antibacterial activity against Bacillus cereus , Pseudomonas aeruginosa (MIC = 0.063 mM) and higher than silver(I) sulfadiazine (AgSD) (MIC > 0.5 mM) against Staphylococcus aureus as AgNO 3 (MIC = 0.063 mM) and higher than silver(I) sulfadiazine (AgSD) (MIC > 0.5 mM) against Pseudomonas aeruginosa . In addition, complex AgPro exerted a strong cytotoxic effect against the tested MDA-MB-231 and Jurkat cancer cell lines (IC 50 values equal to 3.7 and 3.0 μM, respectively) compared with AgNO 3 ) of AgPro and AgHyp complexes with bovine serum albumin (BSA) were determined at four different temperatures, and the zeta potential of BSA in the presence of silver(I) complexes was also measured. The 50 = 6.1 (5.7) μM) and even significantly higher selectivity than cisplatin (cisPt) against MDA-MB-231 cancer cell lines (SI = 3.05 (AgPro); 1.16 (cisPt), SI - selectivity index). The binding constants and the number of binding sites ( n ) of AgPro and AgHyp complexes with bovine serum albumin (BSA) were determined at four different temperatures, and the zeta potential of BSA in the presence of silver(I) complexes was also measured. The in ovo method shows the safety of the topical and intravenous application of AgPro and AgHyp. Moreover, the complexes' bioavailability was verified by lipophilicity evaluation from the experimental and theoretical points of view.

Salinomycin is a coccidiostat approved as a feed additive for the prevention of coccidiosis in poultry. Official control of its residues is set by the Commission Delegated Regulation (EU) 2022/1644. The aim of our study was to assess the suitability of three microbial inhibition tests (MITs), Premi ® Test, Explorer 2.0, and the Screening Test for Antibiotic Residues (STAR) linked to the enzyme-linked immunosorbent assay (ELISA), for the screening of salinomycin residues in the tissues of broiler chickens (breast and thigh muscle, heart, liver, gizzard, kidneys, lungs, spleen, skin, and fat) fed commercially produced feed containing 70 mg.kg -1 of salinomycin in the complete feed. The first residue screening (Sampling A) was performed on the last day of administration of the salinomycin-medicated feed (day 30), and the second screening (Sampling B) was performed on the day of slaughter (day 37) after the expiry of the withdrawal period with the feeding of non-medicated feed. Based on the quantitative confirmation of salinomycin residues in the examined chicken tissues by the ELISA method (Sampling A from 0.025 to 0.241 mg.kg -1 ; Sampling B from 0.003 to 0.076 mg.kg -1 ), all the MITs with the preference of the bacterial strain Bacillus stearothermophilus var. calidolactis ATCC 10149 demonstrated the ability to detect the residues of salinomycin in the examined tissues of broiler chickens at the level of the maximum residue limits set from 0.015 to 0.150 mg.kg -1 by Commission Implementing Regulation (EU) 2017/1914 and confirmed the relevance of their sensitivity to the coccidiostat salinomycin.

The presence of antimicrobial residues in products of animal origin is a constant problem for consumer health. The aim of this study was to observe the effect of the addition of humic substances (H), fermented products (F) and a mixture of both (FH) to feed supplemented with the coccidiostat salinomycin, compared with a control group (C), on the content of salinomycin residues in the edible tissues of broiler chickens using two microbial inhibition screening methods, Explorer 2.0 test and the Screening Test for Antibiotic Residues (STAR), and a confirmatory competitive enzyme immunoassay analysis (Salinomycin ELISA Kit). The results of the microbial inhibition tests showed a gradual decline in the positive results in the tissue samples from the last day of salinomycin administration (30th day) tothe last day of fattening (37th day, day of slaughter) in group C and no positive results in the tissue samples from experimental groups H, F and FH slaughtered on the last day of fattening. Using the Salinomycin ELISA Kit, salinomycin was detected in the chicken muscle tissues of all the control and experimental groups. However, no sample from any group contained salinomycin at a concentration exceeding the maximum residue limits set by European law. The high level of significance ( p < 0.001) confirmed the positive influence of the administration of humic substances and fermented products on the content of salinomycin residues in chicken tissues.

Humic substances are organic ubiquitous components arising in the process of chemical and microbiological oxidation, generally called humification, the second largest process of the carbon cycle. The beneficial properties of these various substances can be observed in many fields of life and health, whether it is the impact on the human organism, as prophylactic as well as the therapeutic effects; animal physiology and welfare, which is widely used in livestock farming; or the impact of humic substances on the environment and ecosystem in the context of renewal, fertilization and detoxification. Since animal health, human health and environmental health are interconnected and mutually influencing, this work brings insight into the excellence of the use of humic substances as a versatile mediator contributing to the promotion of One Health.

The work deals with the issue of standardization and more accurate methodology for the isolation of gluten DNA in gluten-free products of plant origin, which is more demanding due to the more complex structure of plant cells. Three isolation methods were compared, of which the combination of glass and zirconium beads, Proteinase K and a commercially produced isolation kit was confirmed to be the most effective procedure. The given isolation procedure was more effective in one-component gluten-free foods, where the concentration of the obtained DNA ranged from 80.4 ± 0.7 to 99.0 ± 0.0 ng/µL. The subsequent PCR reaction revealed the presence of gluten not only in guaranteed gluten-free products (40%), but also in naturally gluten-free foods (50%). These were mainly gluten-free sponge cakes, gluten-free biscuits "Cranberries", cocoa powder, coffee "3in1", and instant coffee.

Lasalocid is a polyether ionophoric coccidiostat used for the prevention of coccidiosis in poultry at a prescribed concentration and during a certain time interval. Due to a public health concern about the presence of coccidiostat residues in poultry, the aim of the present study was to determine the levels of lasalocid residues in the edible tissues of broiler chickens (breast muscle, thigh muscle, heart, liver, gizzard, kidneys and skin/fat) fed commercially produced feed containing 100 mg kg⁻¹) of lasalocid in complete feed throughout the 5-day withdrawal period (WP). The residues were investigated by liquid chromatography coupled with electrospray ionisation (ESI) tandem mass spectrometry (MS/MS) with triple quadrupole. The limit of detection (LOD) and the limit of quantification (LOQ) of the method were 0.47 and 1.44 µg kg⁻¹, respectively. The average recovery based on the matrix-fortified calibrations for chicken tissues ranged between 79% and 98%. Lasalocid was found to accumulate in the liver, followed by the heart, skin/fat, kidneys, thigh muscle and gizzard. The lowest concentrations of lasalocid residues were found in the breast muscle. On day 5 of the WP, residue concentrations of lasalocid did not decline below the LOQ of the method, but were far below the maximum residue level (MRL) established for lasalocid in poultry from 20 to 100 µg kg⁻¹ by European Commission Regulation (EU) No. 37/2010. The results confirmed that the WP established for lasalocid is sufficient to ensure the decline of its residues in the tissues of broiler chickens to the safe residue level.

In this study changes in the concentrations of lactate, phosphates, and pH values of water extracts of muscles of transported and hunted rabbits during ripening were determined. Concentrations of lactate were higher in the muscles of hunted rabbits. The highest differences were obtained 24h after kill/hunt. Concentrations of lactate in the muscles of hunted rabbits were decreasing, while in the muscles of transported rabbits we observed it to increase in the 7th day and then decrease in the 14th day. Higher concentrations of phosphates were found in the muscles of transported wild rabbits. During the ripening process concentrations of phosphates were decreasing in muscles of both groups. Muscles of hunted rabbits had lower pH values during the whole ripening process. Our research showed that concentrations of lactate, phosphates and pH value post-mortem depended on the perimortal situations., (Copyright © 2011 Elsevier Ltd. All rights reserved.)