Journal
JOURNAL OF FISH DISEASES
Volume 44, Issue 5, Pages 541-551Publisher
WILEY
DOI: 10.1111/jfd.13344
Keywords
Aeromonas hydrophila; Centrarchidae; Epistylis; phylogenetics; red sore disease
Funding
- Georgia Department of Natural Resources and Alabama Agricultural Research Station
Ask authors/readers for more resources
The causative agents of red sore disease are a species of Epistylis and Aeromonas hydrophila, identified through morphological features and genetic sequences. The ciliate was classified as Epistylis cf wuhanensis, while the bacterium was identified as Aeromonas hydrophila. Lesions in affected fish showed various tissue damage, with this being the first nucleotide sequence information for the symbionts associated with RSD.
The aetiological agents of red sore disease (RSD) reportedly comprise a taxonomically ambiguous stalked ciliate (a species of Epistylis) and Aeromonas hydrophila. The taxonomic identity of each pathogen remains provisional: using supra-specific morphological features for the ciliate and culture-based methods that cannot delineate bacterial strain. On 7 and 9 November 2017 and 28 May 2020, biologists and anglers reported a local epizootic (Hiwassee and Chattahoochee river basins; Georgia) wherein some moribund fish presented RSD-like lesions. The ciliates were assigned to Epistylis by morphology. The ciliate is regarded as Epistylis cf wuhanensis, as nucleotide sequences from its small subunit ribosomal DNA were identical to those of Epistylis wuhanensis. The bacterium was identified as Aeromonas hydrophila by phenotypic markers and nucleotide sequences from the DNA gyrase subunit B; our sequences comprised 3 strains and phylogenetically were recovered sister to strains of Eurasian origin. Histological sections of lesions revealed effacement or partial deterioration of the epithelium covering scales, scale loss, haemorrhaging, necrosis, oedema, and extensive inflammatory infiltrate in the dermis. This is the first nucleotide sequence information for the symbionts implicated in RSD.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available