Pathological changes in cultured channel catfish Ictalurus punctatus spontaneously infected with Streptococcus iniae

• Published in: Diseases of aquatic organisms Vol. 95; no. 3; pp. 203 - 208
• Main Authors: CHEN, De-Fang, WANG, Kai-Yu, YI GENG, JUN WANG, HUANG, Xiao-Li, MING HE
• Format: Journal Article
• Language: English
• Published: Oldendorf Inter-Research 12.07.2011
• Subjects: Animal and plant ecology; Animal aquaculture; Animal productions; Animal, plant and microbial ecology; Animals; Biological and medical sciences; Fish Diseases - microbiology; Fish Diseases - pathology; Fresh water ecosystems; Freshwater; Fundamental and applied biological sciences. Psychology; Ictaluridae; Ictalurus punctatus; Kidney - microbiology; Liver - microbiology; Spleen - microbiology; Streptococcal Infections - microbiology; Streptococcal Infections - pathology; Streptococcal Infections - veterinary; Streptococcus - classification; Streptococcus iniae; Synecology; Freshwater environment; Vertebrata; Histopathology; Channel catfish; Streptococcus iniae; Pisces; Ictalurus punctatus
• ISSN: 0177-5103; 1616-1580
• DOI: 10.3354/dao02354

The pathological changes present in channel catfish Ictalurus punctatus spontaneously infected by Streptococcus iniae are described. The most consistent gross findings were marked petechial hemorrhages of the skin and congestion of internal organs, particularly the liver, spleen and kidneys. Other features included color fading at the edge of fin rays, enteritis and ascites. Histological examination showed oedema, degeneration and necrotic changes in many organs. Further, hepatitis, splenitis, interstitial nephritis, and meningitis with numerous monocyte and neutrocyte infiltrates were evident. Intact S. iniae cells were seen in macrophages. Apparently, spontaneous S. iniae infection caused acute septicaemia in channel catfish. This is the first histopathological report on channel catfish naturally infected with S. iniae.