Analysis of the Situation of Drug Resistance of Aeromonas from River Crabs in Jiangsu Province in 2021

In order to investigate the prevalent rules and characteristics of Aeromonas bacteria from river crabs in Jiangsu Province, the samples of river crabs were collected from the 20 counties (cities, districts) in Jiangsu Province, such as Sihong, Wuzhong and Xiangcheng, etc., for the isolation and cultivation of Aeromonas. The genus identification was conducted by using the PCR-amplified sequencing method of 16 S rRNA gene-specific primers, and the in vitro chemosensitivity test was also carried out. The results showed that a total of 182 strains of Aeromonas were isolated and identified from hepatopancreas, gill filaments and intestinal samples of river crabs, among which Aeromonas veronii accounted for the largest proportion (64%). The results of in vitro chemosensitivity test showed that the isolated strains of Aeromonas from river crabs had the lowest resistance rate to enrofloxacin, only 4.95%, while the sensitivity rate was the highest (86.81%). By comparing the data of drug resistance from 2019 to 2021, it was found that the resistance rate of Aeromonas from river crabs to enrofloxacin has remained at a relatively low level in the past three years. Compared with the other four representative species such as Macrobrachium nipponense, Carassius auratus, Ctenopharyngodon idella and Procambarus shrimp in the aquaculture in Jiangsu Province, the overall conditions of the drug resistance of Aeromonas from river crabs was generally good, and the degree of drug resistance was relatively low. The research results could provide a certain basis for the prevention and treatment of bacterial diseases caused by Aeromonas from river crabs in the region.