Khả năng nhạy với kháng sinh của vi khuẩn gây bệnh đốm trắng nội tạng trên cá lóc (Channa striata) ở Trà Vinh

Abstract

This study was conducted to investigate the susceptivity of bacterial pathogens Aeromonas schubertii causing white spot disease on snakehead fish (Channa striata) in intensive ponds in Tra Vinh province. All 24 isolates were tested for physiological, biochemical indicators before proceeding antibiotic susceptibility with 15 antimicrobial agents. Then 4 representative isolates were chosen to determine the minimal inhibitory concentration (MIC) with 4 antibiotics (colistin, doxycycline, erythromycin, amoxicillin) by method with broth dilution. The results showed that A. schubertii was highly susceptible with doxycycline (83,33%) and colistin (79,17%), highly resistance to oxytetracycline (79,17%), florfenicol (79,17%), erythromycin (70,83%) and novobiocin (62,5%). A. schubertii isolates showed fully resistant to ampicillin, amoxicillin and rifampicin. The results from determining the MIC values showed that 4 isolates were highly susceptible to colistin (MIC = 0,25-0,5 μg/mL) and doxycycline (MIC = 4 μg/mL), resistant to erythromycin (MIC = 8 μg/mL) and fully resistant to amoxicillin (MIC = 512 μg/mL).