Exploring Antibiotic Resistance Patterns in Isolates from Domestic Animals in Southern Italy

Background/Objectives: Surveillance studies focusing on clinically relevant infections confirm that antimicrobial resistance (AMR) is widespread among bacterial isolates from European households and livestock domestic animals. Due to the shared interface between humans and these animals, as well as an increasing trend in the number of pets per person, the spread of AMR is of concern. Methods: In this study, antibiogram reports issued at the bacteriology laboratory of the Department of Veterinary Medicine of the University of Bari from 2020 to 2025 were reviewed and analyzed using descriptive and statistical methods to explore the AMR patterns. Results: Two hundred and twenty-eight results were included, comprising 2599 individual tests. A total of 76 molecules across 25 antibiotic classes were tested. Ear swabs were the most common sample type, and Staphylococcus spp. and E. coli were the most isolated bacteria. Two-thirds of the isolates were susceptible to at least one substance classified by the European Medicine Agency (EMA) as category D. Fairly low non-susceptibility (NS) results were obtained for sulfamethoxazole-trimethoprim (D category), gentamicin (C category), and enrofloxacin (B category). Conclusions: An increase in the NS trend was observed over the five-year period. Overall, the results support the need for continuous antibiotic stewardship.