Effects of short-term acid and aluminum exposure on the parr-smolt transformation in Atlantic salmon (Salmo salar): Disruption of seawater tolerance and endocrine status

Piscirickettsia salmonis, the etiological agent of the Salmon Rickettsial Septicemia (SRS), is one the most serious health problems for the Chilean salmon industry. Typical antimicrobial strategies used against P. salmonis include antibiotics and vaccines, but these applications have largely failed. A few years ago, the first attenuated-live vaccine against SRS (ALPHA JECT LiVac® SRS vaccine) was released to the market. However, there is no data about the agents involved in the activation of the immune response induced under field conditions. Therefore, in this study we evaluated the expression profile of a set of gene markers related to innate and adaptive immunity in the context of a cellular response in Atlantic salmon (Salmo salar) reared under productive farm conditions and immunized with a live-attenuated vaccine against P. salmonis. We analyzed the expression at zero, 5-, 15- and 45-days post-vaccination (dpv). Our results reveal that the administration of the attenuated live SRS LiVac vaccine induces a short-term upregulation of the cellular-mediated immune response at 5 dpv modulated by the upregulation of ifnα, ifnγ, and the cd4 and cd8α T cell surface markers. In addition, we also registered the upregulation of il-10 and tgfβ. Altogether, the results suggest that a balanced activation of the immune response took place only at early times post-vaccination (5 dpv). The scope of this short-term upregulation of the cellular-mediated immune response against a natural outbreak in fish subjected to productive farm conditions deserves further research.

Download Full-text

A COMPARATIVE STUDY OF SMOLTIFICATION IN SEA TROUT (SALMO TRUTTA L.) AND ATLANTIC SALMON (SALMO SALAR L.): SEAWATER TOLERANCE AND THYROID HORMONE TITRES

Biology & Environment Proceedings of the Royal Irish Academy ◽

10.1353/bae.2006.0017 ◽

2006 ◽

Vol 106B (1) ◽

pp. 35-47

Author(s):

D.T.G. Quigley ◽

M.J. Harvey ◽

T.J. Hayden ◽

C. Dowling ◽

M.P. O'Keane

Keyword(s):

Thyroid Hormone ◽

Atlantic Salmon ◽

Comparative Study ◽

Salmo Salar ◽

Salmo Trutta ◽

Sea Trout ◽

Atlantic Salmon Salmo Salar ◽

Seawater Tolerance

Download Full-text

Influence of fluoride on aluminum toxicity to Atlantic salmon (Salmo salar)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-834 ◽

1995 ◽

Vol 52 (11) ◽

pp. 2432-2444 ◽

Cited By ~ 5

Author(s):

Steven J. Hamilton ◽

Terry A. Haines

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Aluminum Toxicity ◽

Gill Tissue ◽

Fish Length ◽

Aluminum Exposure ◽

Fluoride Treatment ◽

Atlantic Salmon Salmo Salar ◽

Secondary Lamellae ◽

Gill Lamellae

Atlantic salmon (Salmo salar) alevins were exposed to various aluminum (0–4700 μg/L) and four fluoride (0–500 μg/L) concentrations at two pH values (5.5 and 6.5) for 4- and 30-d periods. In the 4-d tests, aluminum with fluoride was less toxic at pH 6.5 than at pH 5.5, whereas without fluoride, pH had no effect. In the 30-d test, mortality in all treatments was 17–21% at pH 5.5, but only 3–7% at pH 6.5. Fish length and weight after 30 d were reduced in all fluoride–aluminum treatments at pH 5.5, but only in the 200-μg/L aluminum without fluoride treatment at pH 6.5. At pH 5.5 and 6.5 without aluminum, histomorphological examinations revealed no abnormalities in gill tissue. However, in aluminum exposure with no fluoride, gill filaments and secondary lamellae were swollen and thickened. Addition of fluoride at pH 6.5 alleviated some gill damage. At pH 5.5 and 200 μg/L aluminum, addition of 100 μg/L fluoride reduced swelling of gill lamellae, but 200 μg/L fluoride did not reduce swelling. Low fluoride concentrations (< 100 μg/L) may reduce gill morphological damage in fish exposed to aluminum in acidic waters, whereas high fluoride concentrations (> 100 μg/L) may not reduce aluminum-induced effects.

Download Full-text

Congruence between automatic fish counter data and rod catches of Atlantic salmon (Salmo salar) in Scottish rivers

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2005.01.016 ◽

2005 ◽

Vol 62 (4) ◽

pp. 808-817 ◽

Cited By ~ 16

Author(s):

J.L. Thorley ◽

D.M.R. Eatherley ◽

A.B. Stephen ◽

I. Simpson ◽

J.C. MacLean ◽

...

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Spatial Scales ◽

Short Term ◽

Atlantic Salmon Salmo Salar ◽

Residual Variation ◽

Term Variation ◽

Temporal And Spatial ◽

Counter Data

Abstract The potential utility of rod catch and automatic fish counter data as measures of Atlantic salmon (Salmo salar) abundance in Scottish rivers was assessed. The trend (long-term) and residual (short-term) variation in the net annual count for 12 counters were compared with the trend and residual variation in either the annual or spring (February–May) rod catch, as appropriate, for the fisheries district in which the counter is located. Trends were fitted using a cubic smoothing spline and compared using reference bands. In eight of the 12 short-term comparisons, the residuals were significantly correlated. The four incongruent short-term comparisons involved the shortest time-series (≤12 years) or lowest rod catches. In eight of the 12 long-term comparisons, the trends fell within the reference bands in 50% or more of the years. Rod catch and counter data both contain useful information about Atlantic salmon abundance, albeit on different temporal and spatial scales, which should be integrated into assessment schemes.

Download Full-text