title: Histologic and molecular characterization of Edwardsiella piscicida infection in largemouth bass (Micropterus salmoides).
abstract: The genus Edwardsiella is composed of a diverse group of facultative anaerobic, gram-negative bacteria that can produce disease in a wide variety of hosts, including birds, reptiles, mammals, and fish. Our report describes the isolation and identification of Edwardsiella piscicida associated with chronic mortality events in 2 separate captive largemouth bass (Micropterus salmoides) populations in New York and Florida. Wet-mount biopsies of skin mucus, gill, kidney, and spleen from several affected largemouth bass contained significant numbers of motile bacteria. Histologic examination revealed multifocal areas of necrosis scattered throughout the heart, liver, anterior kidney, posterior kidney, and spleen. Many of the necrotic foci were encapsulated or replaced by discrete granulomas and associated with colonies of gram-negative bacteria. Initial phenotypic and matrix-assisted laser desorption ionization-time of flight mass spectrometric analysis against existing spectral databases of recovered isolates identified these bacteria as Edwardsiella tarda Subsequent molecular analysis using repetitive sequence mediated and species-specific PCR, as well as 16S rRNA, rpoB, and gyrB sequences, classified these isolates as E. piscicida As a newly designated taxon, E. piscicida should be considered as a differential for multiorgan necrosis and granulomas in largemouth bass.
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim) fogelsb@uga.edu.
authors.forename: Susan B
authors.initials: SB
authors.lastname: Fogelson
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Barbara D
authors.initials: BD
authors.lastname: Petty
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Reichley
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Cynthia
authors.initials: C
authors.lastname: Ware
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Paul R
authors.initials: PR
authors.lastname: Bowser
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Crim
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Rodman G
authors.initials: RG
authors.lastname: Getchell
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Sams
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Hélène
authors.initials: H
authors.lastname: Marquis
authors.affiliation: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (Fogelson)North Florida Aquatic Veterinary Services, Fort White, FL (Petty)Thad Cochran National Warmwater Aquaculture Center, Aquatic Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS (Reichley, Ware, Griffin)Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (Bowser, Getchell, Sams, Marquis)IDEXX BioResearch, Columbia, MO (Crim)Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO (Crim).
authors.forename: Matt J
authors.initials: MJ
authors.lastname: Griffin
mesh_terms: D000818:Animals; D001492:Bass; D020594:Edwardsiella / Q000235:genetics / Q000302:isolation & purification*; D004756:Enterobacteriaceae Infections / Q000453:epidemiology / Q000662:veterinary*; D005393:Fish Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D005431:Florida / Q000453:epidemiology; D009518:New York / Q000453:epidemiology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D013045:Species Specificity
chemical_list: D012336:RNA, Ribosomal, 16S
keywords: Edwardsiella piscicida; Micropterus; gyrB; histopathology; largemouth bass