The aim of this study was to investigate the drug resistance profile of Escherichia coli (E. coli) isolated from Tibetan piglets having white score diarrhea in Qinghai Tibetan Plateau of China. A total of 81 E. coli strains were isolated from 83 fecal samples. While commonly used antimicrobial drugs and polymerase chain reaction (PCR) were used to detect the drug resistant and representative drug resistance genes. The results showed that the isolated E. coli was highly resistant to medemycin (100%), aztreonam (87.65%), tobramycin (55.56%), and kanamycin (46.91%), and lower resistant to cefoxitin (40.74%) and ceftazidime (30.86%). Isolates tolerant to 3 or more than 3 antimicrobial drugs accounted for 87.65% and were classified as multidrug resistant (MDR). The prevalent genes detected were bla_TEM and aac-Im, belonging to beta-Lactamases and aminoglycosides, class respectively. In conclusion, the antimicrobial resistance of E. coli from free-ranging Tibetan piglets showed a high tolerant rate than other regions of China. The results of the present study revealed that, the use of single antibiotic for a long period of time was the main reason that increased the antibiotic resistance in Tibetan pigs. Therefore, the insensitive antimicrobial drugs should be avoided in clinical treatment of bacterial diseases.

Key words: Antimicrobial resistance, Escherichia coli (E.coli), Tibetan piglets, Tolerance, White score diarrhea