No abstract

No abstract

EFSA was requested to: 1) assess the risk for the development of antimicrobial resistance (AMR) due to feeding on farm of calves with colostrum potentially containing residues of antibiotics; 2) assess the risk for the development of AMR due to feeding on farm of calves with milk of cows treated during lactation with an antibiotic and milked during the withdrawal period, and 3) propose possible options to mitigate the risk for the development of AMR derived from such practices. Treatment of dairy cows during the dry period and during lactation is common in the EU Member States. Penicillins, alone or in combination with aminoglycosides, and cephalosporins are most commonly used. Residue levels of antimicrobials decrease with the length of the dry period. When the interval from the start of the drying-off treatment until calving is as long as or longer than the minimum specified in the Summary of Product Characteristics of the antimicrobial, faecal shedding of antimicrobial-resistant bacteria will not increase when calves are fed colostrum from treated cows. Milk from cows receiving antimicrobial treatment during lactation contains substantial residues during the treatment and withdrawal period. Consumption of such milk will lead to increased faecal shedding of antimicrobial-resistant bacteria by calves. A range of possible options exist for restricting the feeding of such milk to calves, which could be targeting the highest priority critically important antimicrobials. b-Lactamases can reduce the concentration of b-lactams which are the most frequently used antimicrobials in milking cows. Options to mitigate the presence of resistant bacteria in raw milk or colostrum are mainly based on thermal inactivation. An editorial correction was carried out that does not materially affect the contents or outcome of this scientific output. To avoid confusion, the older version has been removed from the EFSA Journal, but is available on request, as is a version showing all the changes made.

No abstract

No abstract

No abstract

No abstract

The STAR protocol is a Five Plate Test (FPT) developed several years ago at the 24 Community Reference Laboratory (CRL) for the screening of antimicrobial residues in milk and muscle. This paper presents the validation of this method according to the European 26 Decision 2002/657/EC and to an internal guideline for validation. A validation protocol based 27 on "simulated tissues" and on a list of 16 representative antimicrobials to be validated has 28 been implemented in our laboratory during several months for the STAR protocol. The 29 performance characteristics of the method have been determined (specificity, detection 30 capabilities CCβ, applicability, ruggedness). In conclusion, the STAR protocol is applicable to 31 the broad spectrum detection of antibiotic residues in muscles of different animal species 32 (pig, cattle, sheep, poultry). The method has good specificity (false positive rate 4%). The 33 detection capabilities have been determined for 16 antibiotics from different families in 34 relation to their respective Maximum Residue Limit (MRL): beta-lactams (penicillins and 35 cephalosporins ≤ MRL), tetracyclines (≤MRL and ≤ 2.5 MRL), macrolides (2 MRL), 36 quinolones (≤ 2 MRL), some sulphonamides (≤ 3 MRL), trimethoprim (2 MRL). However, the 37 sensitivity of the STAR protocol towards aminoglycosides (> 8 MRL) and florfenicol (≤ 10 38 MRL) was unsatisfactory (>> MRL). The two objectives of this study have been met: firstly to 39 validate the STAR protocol according to the European decision 2002/657/EC, then 40 demonstrate that the validation guideline (Anonymous 2010) developed to implement this 41 decision is applicable to microbiological plate tests even for muscle. The use of "simulated 42 tissue appeared as a good compromise between spiked discs with antibiotic solutions and 43 incurred tissues. In addition, the choice of a list of representative antibiotics allowed the 44 reduction of the scope of the validation, which was already costly in time and effort.