title: Mass mortality in ornamental fish, Cyprinus carpio koi caused by a bacterial pathogen, Proteus hauseri.
abstract: Moribund koi carp, Cyprinus carpio koi, from a farm with 50% cumulative mortality were sampled with the aim of isolating and detecting the causative agent. Three bacterial species viz., Citrobacter freundii (NSCF-1), Klebsiella pneumoniae (NSKP-1) and Proteus hauseri [genomospecies 3 of Proteus vulgaris Bio group 3] (NSPH-1) were isolated, identified and characterized on the basis of biochemical tests and sequencing of the 16S rDNA gene using universal bacterial primers. Challenge experiments with these isolates using healthy koi carp showed that P. hauseri induced identical clinical and pathological states within 3 d of intramuscular injection. The results suggest P. hauseri (NSPH-1) was the causative agent. In phylogenetic analysis, strain NSPH-1 formed a distinct cluster with other P. hauseri reference strains with ≥99% sequence similarity. P. hauseri isolates were found sensitive to Ampicillin, Cefalexin, Ciprofloxacin and Cefixime and resistant to Gentamycin, Oxytetracycline, Chloramphenicol, and Kanamycin. The affected fish recovered from the infection after ciprofloxacin treatment.
authors.affiliation: National Bureau of Fish Genetic Resources Cochin Unit, CMFRI Campus, P.O. Number 1603, Kochi 682018, Kerela, India.
authors.forename: Raj
authors.initials: R
authors.lastname: Kumar
authors.affiliation: National Bureau of Fish Genetic Resources Cochin Unit, CMFRI Campus, P.O. Number 1603, Kochi 682018, Kerela, India. Electronic address: rajathanga@yahoo.co.in.
authors.forename: T Raja
authors.initials: TR
authors.lastname: Swaminathan
authors.affiliation: National Bureau of Fish Genetic Resources Cochin Unit, CMFRI Campus, P.O. Number 1603, Kochi 682018, Kerela, India.
authors.forename: Rahul G
authors.initials: RG
authors.lastname: Kumar
authors.affiliation: National Bureau of Fish Genetic Resources Cochin Unit, CMFRI Campus, P.O. Number 1603, Kochi 682018, Kerela, India.
authors.forename: Arathi
authors.initials: A
authors.lastname: Dharmaratnam
authors.affiliation: National Bureau of Fish Genetic Resources Cochin Unit, CMFRI Campus, P.O. Number 1603, Kochi 682018, Kerela, India.
authors.forename: V S
authors.initials: VS
authors.lastname: Basheer
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226002, India.
authors.forename: J K
authors.initials: JK
authors.lastname: Jena
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002347:Carps / Q000382:microbiology*; D016971:Citrobacter freundii / Q000235:genetics / Q000302:isolation & purification; D004275:DNA, Ribosomal / Q000235:genetics; D004196:Disease Outbreaks; D004756:Enterobacteriaceae Infections; D005393:Fish Diseases / Q000401:mortality*; D005398:Fisheries; D007194:India; D007710:Klebsiella Infections; D007711:Klebsiella pneumoniae / Q000235:genetics / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D011511:Proteus / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D011512:Proteus Infections / Q000401:mortality*
chemical_list: D000900:Anti-Bacterial Agents; D004275:DNA, Ribosomal
keywords: Cyprinus carpio koi; Koi carp; Phylogeny; Proteus hauseri; Tail rot; Treatment