Suchergebnisse

AbstractThe residual patterns of 23 target antibiotics in five classes of compound in catchment sediments of a rapidly urbanizing city in east China were studied. A total of 14 antibiotics were detected in the catchment. The dominant classes were tetracyclines and fluoroquinolones and these occurred at substantial concentrations. High environmental risk at the sites sampled may be associated with antibiotics detected at high concentrations. For example, at one site chlortetracycline was found to occur at concentrations ≤ 4496 ng/g. Source traceability indicates that high intensity of urbanization (e.g. hospitals and livestock farms) had a high spatial relationship with sites of high antibiotic contaminations. Urban and suburban areas had some impacts on antibiotic residues in the catchment, especially on veterinary antibiotics such as chlortetracycline in suburban areas. Moreover, antibiotics detected at high concentrations in urban areas included fluoroquinolones associated with human medicine.

Over the past few decades quinolones are the most dynamically developed group of synthetic antimicrobials. They are also known as 4-quinolone, quinolone carboxylic acids and fluoroquinolones. They have excellent activity against gram-negative and gram-positive bacteria. Therefore they are the most commonly used classes of antibiotics in clinical medicine. Problem of most importance in fish is the effective control of infectious diseases. Thus the essential strategy is the use of antimicrobial agents. In the same time quinolones are preferred group for treatment of bacterial diseases in fish. Literature data show a disturbing perspective – the increase of cases of uncontrolled use of antimicrobials, which leads to danger for consumers, despite of definitive legislation in this area. Data of many authors show a great number of productive animals receive antimicrobials for food and therapeutic purposes. This is in connection to the uncontrolled sale of antibiotics in the veterinary pharmacies and their use by owners to treat their animal. The withdrawal periods are not respected. Therefore, the presence of residues of antimicrobial substances in meat and meat products, milk and dairy products, fish, eggs and honey are not uncommon. In series of studies enrofloxacin and ciprofloxacin residues have been identified in meat of two fish species: rainbow trout (Oncorhynhus mykiss) and common (cultural) carp (Cyprinus carpio) during storage. Pharmacokinetic studies have been carried out during storage. The results for enrofloxacin residues in trout meat during frozen storage determined a distinguished decrease after 180th day, while ciprofloxacin residues established a long time reduction to 270th day of the storage. Otherwise, the presence of enrofloxacin and ciprofloxacin residues in common carp meat showed the amount of enrofloxacin in 1st month of the study changed scarcely. In three months at a temperature of minus 18 ° C it was established a distinguished decrease of enrofloxacin. It was maintained until the end of ...

Monitoring of food products from animal origin for the presence of antimicrobial residues is preferably done using microbial screening methods because of their high cost-effectiveness. Traditionally applied methods fail to detect the maximum residue limits which were established when EU Council Regulation 2377/90 came into effect. Consequently, during the last decade this has led to the development of improved microbial screening methods. This review provides an overview of the efforts expended to bring antibiotic screening methods into compliance with EU legislation. It can be concluded that the current situation is still far from satisfactory.

Tesis por compendio ; In Mediterranean countries, sheep and goat's milk production has traditionally been destined for the manufacture of cheese, often as raw milk. Cheese quality is closely related to milk composition but also to hygienic aspects such as somatic cell count, bacteriology or presence of antibiotic residues, currently regulated by European legislation. The implications of the presence of antibiotic residues in milk as a result of veterinary treatments include negative effects on consumer's health such as allergies or antibiotic resistance and problems on the manufacturing processes of fermented products. For the screening of milk samples for antimicrobial residues, there are various methods available, microbial inhibitor tests and assays based on specific receptors, both widely used, especially in farms, the dairy industry and control laboratories. Screening methods have been validated for the use in raw milk from cows, but information on the performance of these tests in sheep and goat's milk is rather limited. The aim of this study was to evaluate the performance of some microbial and receptor-binding screening tests to detect antibiotics in sheep and goat's milk according to Commission Decision 2002/657/EC to determine their suitability to monitor the presence of antibiotic residues in milk and establish the most convenient analytical strategy in Spain. The Detection capability (CCβ) of microbial screening tests, the BRT MRL, the Delvotest MCS SP-NT, the Delvotest MCS Accelerator and the Eclipse 100, was at or below the maximum residue limits (MRLs) for most beta-lactam antibiotics assessed and other non-beta-lactam drugs such as neomycin, tylosin, sulfadiazine and sulfadimethoxine. However, they were less sensitive in the detection of quinolones and tetracyclines at safety levels. When individual milk samples were analysed, microbiological tests showed a higher occurrence of non-compliant results in sheep milk than in goat's milk, being related in all cases to an elevated somatic cell count ...

The use of antibiotics to treat mastitis and other infectious diseases in dairy sheep and goats is a widespread practice nowadays that can, when not properly applied, result in the contamination of the milk supply. Spanish legislation establishes the control of the presence of antibiotic residues in sheep and goat's milk using screening methods that detect, at least, beta-lactam drugs. Microbial inhibitor tests using Geobacillus stearothermophilus var. calidolactis and specific receptor-binding assays are most widely employed for this purpose. The detection rates of screening tests routinely used in Spain have been calculated considering the frequency of use of veterinary drugs commonly applied in ovine and caprine livestock to treat and prevent mastitis as well as the test sensitivity toward these substances at safety levels. In general, the use of a single test allows detecting 62.8-82.4% of the antibiotics employed. For sheep milk, the total detection range achieved with microbial tests was significantly higher than that reached with rapid receptor tests. However, no significant differences between the two types of methods were found when goat's milk was analysed. In both types of milk, the simultaneous use of two screening tests with a different analytical basis increases the total detection range significantly, reaching values ≥ 90% in some cases (81.5-90.1% for sheep and 84.7-92.6% for goats). However, the periodical use of screening tests able to detect quinolones, macrolides or aminoglycosides would be recommended to carry out more efficient screening and ensure the safety of milk and dairy products from sheep and goats.

© INIA. Manuscripts published are the property of the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria SJAR is an Open Access Journal. All articles are distributed under the terms of the Creative Commons Attribution License (CC by-nc/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ; [EN] The use of antibiotics to treat mastitis and other infectious diseases in dairy sheep and goats is a widespread practice nowadays that can, when not properly applied, result in the contamination of the milk supply. Spanish legislation establishes the control of the presence of antibiotic residues in sheep and goat s milk using screening methods that detect, at least, beta-lactam drugs. Microbial inhibitor tests using Geobacillus stearothermophilus var. calidolactis and specific receptor-binding assays are most widely employed for this purpose. The detection rates of screening tests routinely used in Spain have been calculated considering the frequency of use of veterinary drugs commonly applied in ovine and caprine livestock to treat and prevent mastitis as well as the test sensitivity toward these substances at safety levels. In general, the use of a single test allows detecting 62.8-82.4% of the antibiotics employed. For sheep milk, the total detection range achieved with microbial tests was significantly higher than that reached with rapid receptor tests. However, no significant differences between the two types of methods were found when goat s milk was analysed. In both types of milk, the simultaneous use of two screening tests with a different analytical basis increases the total detection range significantly,reaching values ≥ 90% in some cases (81.5-90.1% for sheep and 84.7-92.6% for goats). However, the periodical use of screening tests able to detect quinolones, macrolides or aminoglycosides would be recommended to carry out more efficient screening and ensure the safety of milk and dairy products from sheep and ...

The feeding of waste milk containing antibiotic residues (WMA) to calves has been associated with the shedding of antibiotic-resistant bacteria by calves. However, little is known regarding farmers' intrinsic factors affecting this practice, and on which it would be relevant to intervene in order to change this practice. The objectives of this study were (1) to describe the farmers' intrinsic factors, such as perceived benefits, risks, and social norms related to the feeding of WMA to calves, antibiotic resistance, and antibiotic use, and (2) to evaluate how the feeding of WMA to calves is related to farmers' personal values and perceptions related to WMA feeding and antibiotic resistance. Answers to an online survey were collected from 233 Swiss dairy producers (38.3% response rate). The proportion of respondents who fed WMA to calves was 48.3%. In a hierarchical logistic regression model, only perception factors extracted by factor analysis were associated with the feeding of WMA to calves, namely (in decreasing order of magnitude): farm-level benefits of WMA feeding, the interaction of farm-level benefits with support from governmental authorities, and causes and threats of antibiotic resistance. The results suggest that, in order to reduce the feeding of WMA to calves, communications to dairy producers should focus on changing the perceived benefits of this practice in comparison to those of alternative WMA disposal methods carrying a lower risk of antibiotic resistance. The involvement of veterinarians and governmental authorities in these communications and in supporting producers may increase the successful adoption of alternative WMA disposal methods.

The feeding of waste milk containing antibiotic residues (WMA) to calves has been associated with the shedding of antibiotic-resistant bacteria by calves. However, little is known regarding farmers' intrinsic factors affecting this practice, and on which it would be relevant to intervene in order to change this practice. The objectives of this study were (1) to describe the farmers' intrinsic factors, such as perceived benefits, risks, and social norms related to the feeding of WMA to calves, antibiotic resistance, and antibiotic use, and (2) to evaluate how the feeding of WMA to calves is related to farmers' personal values and perceptions related to WMA feeding and antibiotic resistance. Answers to an online survey were collected from 233 Swiss dairy producers (38.3% response rate). The proportion of respondents who fed WMA to calves was 48.3%. In a hierarchical logistic regression model, only perception factors extracted by factor analysis were associated with the feeding of WMA to calves, namely (in decreasing order of magnitude): farm-level benefits of WMA feeding, the interaction of farm-level benefits with support from governmental authorities, and causes and threats of antibiotic resistance. The results suggest that, in order to reduce the feeding of WMA to calves, communications to dairy producers should focus on changing the perceived benefits of this practice in comparison to those of alternative WMA disposal methods carrying a lower risk of antibiotic resistance. The involvement of veterinarians and governmental authorities in these communications and in supporting producers may increase the successful adoption of alternative WMA disposal methods.