Characteristics and antibiotic sensitivity of Streptococcus iniae isolated from sturgeon (Acipenser baerii)
Vol. 135 No. 3B (2026), Original Article
Vol. 135 No. 3B (2026)

Characteristics and antibiotic sensitivity of Streptococcus iniae isolated from sturgeon (Acipenser baerii)

Original Article
https://doi.org/10.26459/hueunijard.v135i3B.7687
Published 2026-05-22
Nguyen Thi Xuan Hong
University of Agriculture and Forestry, Hue University, 102 Phung Hung St., Hue, Vietnam
Nguyen Thi Thu Giang
Agricultural Extension Center, 14 Phung Hung St. Hue, Vietnam

Keywords

Acipenser baerii
bệnh xuất huyết
độ nhạy kháng sinh
Streptococcus iniae Acipenser baerii
antibiotic sensitivity
hemorrhagic disease
Streptococcus iniae

Abstract

This study aimed to identify and evaluate the antibiotic susceptibility of the bacterial pathogen causing hemorrhagic disease in cultured sturgeon (Acipenser baerii) at the nursing stage in A Luoi, Hue city. Bacterial isolates were characterized using biochemical tests (API 20 Strep) and species-specific PCR The results that all isolates were Streptococcus iniae, showing typical characteristics including Gram-positive cocci, negative oxidase and catalase reactions, and hemolytic activity. PCR amplification yielded a specific product of approximately 870bp. Antibiotic susceptibility testing using the disk diffusion method demonstrated that S. iniae isolated from 12 sturgeon disease samples exhibited high sensitive to most tested antibiotics, with inhibition zone diameters ranging from 16,0 to 38,0 mm. The greatest antibacterial activity was observed for Cephalexin (30 µg) and Amoxicillin (10 µg), which produced inhibition zone of 38.0 and 36.0 mm, respectively.

https://doi.org/10.26459/hueunijard.v135i3B.7687

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