Antimicrobial resistance in bacterial isolates from production animals and the possibilities of control

The contribution of food-producing animals or foods to public health risks by ESBL and/or AmpC producing bacteria is related to specific plasmid-mediated ESBL and/or AmpC genes encoded by a number of organisms. The predominant ESBL families encountered are CTX-M, TEM, and SHV, the predominant AmpC family is CMY. The most common genes associated with this resistance in animals are bla CTX-M-1 (the most commonly identified ESBL), and bla CTX-M-14, followed by bla TEM-52 and bla SHV-12. The bacterial species most commonly identified with these genes are Escherichia coli and non-typhoidal Salmonella. ESBL/AmpC transmission is mainly driven by integrons, insertion sequences, transposons and plasmids, some of which are homologous in isolates from both food-production animals and humans. 
The use of antimicrobials is a risk factor for the selection and spread of resistant clones, resistance genes and plasmids. Since most ESBL- and AmpC-producing strains carry additional resistances to other commonly-used veterinary drugs and it is not restricted specifically to the use of cephalosporins.
The present point of view presents some of the most important theoretical component of antimicrobial resistance and some of the current topics which are debated in EU.