Antibiotic Consumption on Dairy and Beef Cattle Farms of Central Italy Based on Paper Registers.

The overuse of antibiotics in livestock contributes to the antibiotic resistance pandemic. The assessment of the actual antibiotic consumption is crucial in limiting the expansion of the problem effectively. The aim of this study was to provide the first qualitative and quantitative analysis of antimicrobial usage using data from paper-based registers on dairy and beef farms located in the Umbria region, Italy. Antimicrobial therapies of a one-year period were collected from 101 farms with at least 50 cattle each. Defined daily doses (DDDvet) and defined course doses (DCDvet) were calculated per administration route and antimicrobial class. The total courses administered were fewer in beef (330.7 × 10-3 DCDvet/year) than in dairy farms (1034.1 × 10-3 DCDvet/year). The use of the highest priority critically important antimicrobials (HPCIAs) was higher (p = 0.0033) in dairy than in beef herds. In terms of DDDvet, the parenteral fluoroquinolone administration ranked second and fourth on dairy and beef farms, respectively; the consumption of beta-lactams was ten times higher on dairy than on beef farms. Our results confirm that intensive dairy management practices are associated with increased antibiotic consumption and highlight the necessity to strengthen the existing stewardship programs by involving all stakeholders in effective antimicrobial resistance reduction plans.

Antibiotic resistance pattern and virulence genesin avian pathogenic Escherichia coli (APEC) from different breeding systems.

Colibacillosis is the most frequent bacterial disease in avian species and antimicrobials are the main weapon to reduce incidence and mortality associated to it. However, indiscriminate use of antibiotics may lead to therapy failure and economic losses for the breeder. The aims of this study were to, determine the antibiotic resistance of Escherichia coli isolates, evaluate the correlation between E. coli isolation and systems of breeding included in this study, and identify the avian pathogenic E.coli (APEC) amongst the E. coli strains isolated. A total of 51 E. coli strains were subjected to antimicrobial susceptibility test and they were screened for the presence of virulence genes through PCR. Resistance was most frequently detected against ampicillin and nalidixic acid meanwhile E. coli isolates showed less resistance to the cephalosporins. Overall, 40% of the isolates showed resistance to at least three or more antimicrobials and 16/51 isolates were defined APEC strains. The virulence genes iucD, cvi/cva, irp2 and iss were detected from all 16 APEC strains. The virulence genes tsh, vat, papC, and astA were detected from 11, 7, 5 and 3 APEC strains, respectively. Results demonstrated the importance of studies on APEC and antibiotic resistance genes in Italy, and it was shown that the systems of breeding might influence the antibiotic resistanc.