1. Isolation and identification of vapA-absent Aeromonas salmonicida in diseased snakehead Channa argus in China.
- Author
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Sun XN, Wang Q, Wang YF, Tao Y, Zheng CL, Wang MH, Che MY, Cui ZH, Li XL, Zhang Q, Xu MX, Wang S, Nie P, and Sun YL
- Subjects
- Animals, China, Bacterial Proteins genetics, Perciformes microbiology, Microbial Sensitivity Tests, Fishes, Aeromonas salmonicida genetics, Aeromonas salmonicida isolation & purification, Aeromonas salmonicida drug effects, Aeromonas salmonicida pathogenicity, Aeromonas salmonicida classification, Fish Diseases microbiology, Phylogeny, Anti-Bacterial Agents pharmacology, Gram-Negative Bacterial Infections microbiology, Gram-Negative Bacterial Infections veterinary
- Abstract
Aeromonas salmonicida is the typical pathogen causing furunculosis, reported widely in salmonids. Because of multiple serotypes, the control of A. salmonicida-caused disease has increasingly received much attention. Recently, A. salmonicida infection was reported in non-salmonid fish species. Here, a pathogenic A. salmonicida, named as As-s, was isolated from cultured snakehead (Channa argus) in a local fish farm in Shandong, China. As-s displayed clear hemolysis, amylase, and positive catalase activities, and grew at a wide range of temperatures (10-37 °C) and pH values (5.5-8.5). As-s was highly sensitive to cefuroxime sodium, ceftriaxone, ceftazidime, piperacillin, and cefoperazone and also apparently sensitive to chloramphenicol, erythromycin, and 25% cinnamaldehyde. The Virulence array protein gene cloning' results suggested that As-s has this gene compared with the other two vapA-containing strains, despite a close relationship of these strains via phylogenetic analysis. Severe ulcers on skin, muscle, and abnormal liver, and hemorrhage in pectoral/ventral fins and anal region were observed, and exophthalmos were also noticed in infected juvenile snakehead, as well as necrosis and infiltration of blood cells emerged in the internal organs using pathological section. In addition, As-s caused high mortality in snakehead, consistently with its immune gene response. This study reports the first isolation of vapA-absent A. salmonicida in snakehead., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
- Published
- 2024
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