title: Pathological changes in cultured channel catfish Ictalurus punctatus spontaneously infected with Streptococcus iniae.
abstract: 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.
authors.affiliation: Department of Basic Veterinary, College of Veterinary Medicine, University, Ya'an 625014, Sichuan, PR China.
authors.forename: De-fang
authors.initials: DF
authors.lastname: Chen
authors.forename: Kai-yu
authors.initials: KY
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Geng
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Huang
authors.forename: Ming
authors.initials: M
authors.lastname: He
mesh_terms: D000818:Animals; D005393:Fish Diseases / Q000382:microbiology / Q000473:pathology*; D007059:Ictaluridae; D007668:Kidney / Q000382:microbiology; D008099:Liver / Q000382:microbiology; D013154:Spleen / Q000382:microbiology; D013290:Streptococcal Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D013291:Streptococcus / Q000145:classification*