Experimental handling stress as infection-facilitating factor for the goldfish ulcerative disease.
Experimental handling stress (EHS) was applied to clinically asymptomatic farmed goldfish (Carassius auratus L.). EHS affected the gills and skin integrity of the fish and was accompanied by increased levels of plasma glucose, cortisol and interleukin-10 (IL-10). EHS application was followed by highly significant enhancement of the rate of infection with a virulent Aeromonas salmonicida isolate. Cumulative ulceration at the initial phase of the ensuing goldfish ulcerative disease (GUD) evidenced a facilitating role of EHS in the onset of GUD. Host susceptibility to the pathogen increased from 40% in unstressed fish to 90% in the stressed fish. A. salmonicida could be reisolated from the early-stage skin lesions only, whereas opportunistic strains, other than A. salmonicida (A. sobria and A. hydrophila), were recovered from progressive-stage ulcers. The implication of these findings in fish aquaculture is discussed.
Dror
Moti
M
Laboratory of Fish Immunology and Genetics, Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
Sinyakov
Michael S
MS
Okun
Eitan
E
Dym
Michal
M
Sredni
Benjamin
B
Avtalion
Ramy R
RR
D048409:Aeromonas salmonicida / Q000276:immunology*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology*; D006054:Goldfish; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D006854:Hydrocortisone / Q000097:blood; D016753:Interleukin-10 / Q000097:blood; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012883:Skin Ulcer / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D013312:Stress, Physiological / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*
D001786:Blood Glucose; D004269:DNA, Bacterial; D016753:Interleukin-10; D006854:Hydrocortisone