膨腹海马嗜环弧菌的分离鉴定、药敏分析及治疗案例OA

In March 2024,a disease outbreak occurred in 60-day-old big-belly seahorses(Hippocampus abdomi-nalis)in an indoor industrialized farm in Dalian,Liaoning Province.The diseased seahorses showed symptoms such as slow movement,anorexia,and significant swim bladder enlargement,with continuous sporadic mortality.To identify the pathogen,a dominant bacterium(strain No.12)was isolated from the internal organs(liver,gall-bladder,spleen,and swim bladder)of the diseased seahorses.The strain was identified as Vibrio cyclitrophicus based on colony morphology observation,selective culture medium cultivation,physiological and biochemical tests,and 16S rDNA sequence analysis.The results of the antimicrobial susceptibility test showed that the strain was highly sensitive to enrofloxacin,compound sulfamethoxazole,and chloramphenicol;moderately sensitive to furazoli-done,polymyxin B,erythromycin,norfloxacin,cefazolin,amikacin,and gentamicin;and resistant to penicillin and ampicillin.According to the drug sensitivity results,enrofloxacin powder(aquaculture use,100g:5g)was mixed into the feed and administered at a dose of 0.3g per kilogram of seahorse body weight,once daily for 5 con-secutive days,accompanied by water quality management and environmental regulation.After 4 days of treatment,the diseased seahorses showed significant improvement in condition,with restored feeding activity and vitality,and mortality ceased.This study is the first to report that Vibrio cyclitrophicus can cause swim bladder enlargement and related symptoms in big-belly seahorses,providing a basis for the diagnosis and precise medication of this disease.