학술논문

Isolation and Classification of a Nocardiaspecies from Diseased Giant Gourami Osphronemus goramy
Document Type
Article
Source
Journal of Aquatic Animal Health; June 1989, Vol. 1 Issue: 2 p154-162, 9p
Subject
Language
ISSN
08997659; 15488667
Abstract
An enzootic caused by bacteria occurred among cultured giant gourami in two freshwater fish farms in Kagoshima, Japan, in 1982. Typical external characteristics of the diseased fish were sloughed scales, exophthalmia, and opaque eyes. Internally, numerous creamy white nodules were found in the gills, spleen, kidney, and liver and a lesser number in the bladder and stomach. Nocardiasp. was isolated from spleen and kidney tissues of all diseased fish examined. To clarify the taxonomic position of the isolates, 164 tests were performed, and results were compared to reference strains of six species of Nocardiaand one species of Rhodococcus. The isolates formed a homogenous group in a single taxon at a similarity of 98.7% based on an average linkage analysis and were clearly separated from the reference strains. The isolated strains were more similar to Nocardia kampachithan to the other representative species. However, 12 distinct differences were found between the isolates and N. kampachi, including growth on nutrient agar, sensitivity to 250 and 500 µg hydroxylamine/mL and 0.01% phenol, tolerance of 0.05% salicylate and 0.1% picric acid in brain-heart infusion medium, hydrolysis of starch, nicotinamidase reaction, and acid from fructose, sucrose, and dextrin. Accordingly, the isolates from the diseased giant gourami were classified as a new species of Nocardia.