Pathology attributed to Mycobacterium chelonae infection among farmed and laboratory-infected Atlantic salmon Salmo salar.
This study was promoted following concern over increasing mortality on 2 farms rearing Atlantic salmon Salmo salar in the Shetland Isles, Scotland. A Mycobacterium sp. was isolated from moribund, market-sized Atlantic salmon. Biochemical tests, lipid analysis and PCR (polymerase chain reaction) techniques confirmed the bacterium to be Mycobacterium chelonae. Multiple greyish-white miliary granuloma-like nodules were observed in several tissues. Dense hard-packed nodules contained abundant acid-fast bacteria. Atlantic salmon injected with M. chelonae remained sub-clinically infected, demonstrating the chronic nature of this disease. The source of the pathogen was not identified.
FRS Marine Laboratory, Aberdeen, Scotland, UK. brunodw@marlab.ac.uk
D W
DW
Bruno
J
J
Griffiths
C G
CG
Mitchell
B P
BP
Wood
Z J
ZJ
Fletcher
F A
FA
Drobniewski
T S
TS
Hastings
D000818:Animals; D005393:Fish Diseases / Q000382:microbiology / Q000473:pathology*; D005398:Fisheries; D005880:Gills / Q000473:pathology; D007668:Kidney / Q000382:microbiology / Q000473:pathology; D008099:Liver / Q000382:microbiology / Q000473:pathology; D009165:Mycobacterium Infections, Nontuberculous / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D016926:Mycobacterium chelonae / Q000302:isolation & purification*; D012474:Salmon; D012606:Scotland; D013154:Spleen / Q000382:microbiology / Q000473:pathology