Experimental Mycobacteriosis in Striped Bass Morone Saxatilis

Authors

D. T. Gauthier, Old Dominion UniversityFollow
M. W. Rhodes
W. K. Vogelbein
H. Kator
C. A. Ottinger

Document Type

Article

Publication Date

2003

DOI

10.3354/dao054105

Publication Title

Diseases of Aquatic Organisms

Volume

54

Issue

2

Pages

105-117

Abstract

Striped bass Morone saxatilis were infected intraperitoneally with approximately 10⁵ Mycobacterium marinum, M. shottsii sp. nov., or M. gordonae. Infected fish were maintained in a flow-through freshwater system at 18 to 21°C, and were examined histologically and bacteriologically at 2, 4, 6, 8, 17, 26, 36 and 45 wk post-infection (p.i.). M. marinum caused acute peritonitis, followed by extensive granuloma development in the mesenteries, spleen and anterior kidney. Granulomas in these tissues underwent a temporal progression of distinct morphological stages, culminating in well-circumscribed lesions surrounded by normal or healing tissue. Mycobacteria were cultured in high numbers from splenic tissue at all times p.i. Standard Ziehl-Neelsen staining, however, did not demonstrate acid-fast rods in most early inflammatory foci and granulomas. Large numbers of acid-fast rods were present in granulomas beginning at 8 wk p.i. Between 26 and 45 wk p.i., reactivation of disease was observed in some fish, with disintegration of granulomas, renewed inflammation, and elevated splenic bacterial densities approaching 10⁹ colony-forming units g^-1. Infection with M. shottsii or M. gordonae did not produce severe pathology. Mild peritonitis was followed by granuloma formation in the mesenteries, but, with 1 exception, granulomas were not observed in the spleen or anterior kidney. M. shottsii and M. gordonae both established persistent infections in the spleen, but were present at densities at least 2 orders of magnitude less than M. marinum at all time points observed. Granulomas in the mesenteries of M. shottsii- and M. gordonae-infected fish resolved over time, and no reactivation of disease was observed.

Original Publication Citation

Gauthier, D. T., Rhodes, M. W., Vogelbein, W. K., Kator, H., & Ottinger, C. A. (2003). Experimental mycobacteriosis in striped bass Morone saxatilis. Diseases of Aquatic Organisms, 54(2), 105-117. doi:10.3354/dao054105

Repository Citation

Gauthier, D. T.; Rhodes, M. W.; Vogelbein, W. K.; Kator, H.; and Ottinger, C. A., "Experimental Mycobacteriosis in Striped Bass Morone Saxatilis" (2003). Biological Sciences Faculty Publications. 167.
https://digitalcommons.odu.edu/biology_fac_pubs/167

ORCID

0000-0002-7075-8453 (Gauthier)