Comparison, using minisatellite DNA profiling, of secondary male contribution in the fertilisation of wild and ranched Atlantic salmon (Salmo salar) ova

1998 ◽  
Vol 55 (9) ◽  
pp. 2011-2018 ◽  
Author(s):  
C E Thompson ◽  
W R Poole ◽  
M A Matthews ◽  
A Ferguson
Keyword(s):  
Reproductive Success ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Minisatellite Dna ◽  
Atlantic Salmon Salmo Salar ◽  
The Difference ◽  
Western Ireland ◽  
Minimum Numbers ◽  
Representative Samples ◽  
Male Genotype

Secondary males, either subdominant adults or, more usually, parr which mature in freshwater, are known to successfully fertilise Atlantic salmon (Salmo salar) ova. This study has estimated the reproductive success of such secondary males in redds formed by pairs of wild and sea-ranched adults. Eight wild and 11 ranched redds were sampled from the Burrishoole system, western Ireland, in two consecutive years. Representative samples of fertilised ova were screened at three minisatellite loci to reconstruct the genotypes of putative anadromous parents and to estimate the proportion of eggs fertilised by secondary males. Multiple paternal genotypes were detected in 18 of the 19 samples, and of the 1484 progeny examined, 593 could not have been derived from the primary adult male genotype. The level of secondary male contribution detected among wild redds from Burrishoole (mean 28.9%) was similar to that found in previous published studies. The level among ranched redds was significantly higher (mean 48.2%) (P = 0.042). The difference was greater when data from 1995 were considered alone, with the average level of secondary male contribution in ranched redds being almost twice that in wild redds. Minimum numbers of secondary males were not significantly different between wild (mean 2.6) and ranched (mean 2.7) redds.

Permeability of the Isolated Atlantic Salmon (Salmo salar) Chorion to Ions as Estimated by Diffusion Potentials

1987 ◽  
Vol 44 (9) ◽  
pp. 1635-1639 ◽  
Author(s):  
R. H. Peterson ◽  
D. J. Martin-Robichaud
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Ion Pairs ◽  
Atlantic Salmon Salmo Salar ◽  
Environmental Perturbations ◽  
Hen’S Egg ◽  
Anions And Cations ◽  
Potential Impact ◽  
Diffusion Potentials ◽  
The Difference

The properties of the teleost chorion and perivitelline fluid may allow the embryo to develop in an ionic medium which differs from ambient. A knowledge of these properties facilitates assessment of the potential impact of environmental perturbations (e.g. low-pH episodes) on the developing embryo. Diffusion potentials are created when differing concentrations of a salt solution are imposed upon the opposite sides of isolated Atlantic salmon (Salmo salar) chorions. These diffusion potentials are related to the mobilities of the cations and anions. The magnitude of the diffusion potentials were measured with NaCl, CaC2, H2SO4, and HCl solutions. The results indicate that both anions and cations permeate the chorion. Chloride appears to have greater mobility through the chorion than does sodium, although the difference in mobility of such ion pairs moving through the chorion is not as great as the difference in their mobilities in aqueous solution. Diffusion potentials obtained with CaCl2 solutions, on the other hand, indicate reduced calcium mobility through the chorion relative to chloride. The decreased mobility of Ca2+ is probably due to adsorption to fixed negative charges on the chorion. The properties of the perivitelline potential of the intact egg could be simulated qualitatively by placing a solution of negatively charged colloid (hen's egg albumin) inside the isolated chorion.

Spawning behaviour and success of mature male Atlantic salmon (Salmo salar) parr of farmed and wild origin

2005 ◽  
Vol 62 (5) ◽  
pp. 1153-1160 ◽  
Author(s):  
Laura K Weir ◽  
Jeffrey A Hutchings ◽  
Ian A Fleming ◽  
Sigurd Einum
Keyword(s):  
Reproductive Success ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
First Generation ◽  
Large Male ◽  
Mature Male ◽  
Atlantic Salmon Salmo Salar ◽  
Spawning Behaviour ◽  
Mature Male Parr ◽  
Variance In Reproductive Success

We examined genetic differences in the reproduction of an alternative maturation phenotype in Atlantic salmon (Salmo salar) by comparing the spawning behaviour and success among farmed, first-generation hybrid, and wild mature male parr raised in similar environments. Parr competed for spawning opportunities in the presence of either wild or farmed large males. There were no consistent differences among groups in aggression; however, there were differences in spawning participation with respect to large male origin and among parr types. There was a strong negative temporal effect on mature male parr spawning participation that differed by parr type; wild and farmed parr were most likely to participate in early spawnings, with hybrids being the most likely to participate in late spawnings. Overall, parr were also less likely to participate in spawnings involving large farmed males. Variance in reproductive success was higher among parr than among large males. Our results are consistent with the hypothesis that there are genetically based behavioural differences among mature male parr of farmed and wild origin that may potentially lead to differences in reproductive success.

A minisatellite DNA marker for discriminating between European and North American Atlantic salmon (Salmo salar)

1995 ◽  
Vol 52 (11) ◽  
pp. 2305-2311 ◽  
Author(s):  
John B. Taggart ◽  
Eric Verspoor ◽  
Paul T. Galvin ◽  
Paloma Morán ◽  
Andrew Ferguson
Keyword(s):  
Atlantic Salmon ◽  
Allele Frequency ◽  
Salmo Salar ◽  
North American ◽  
Nuclear Dna ◽  
Dna Marker ◽  
Low Frequency ◽  
Geographic Range ◽  
Minisatellite Dna ◽  
Atlantic Salmon Salmo Salar

A highly discriminatory and practical nuclear DNA genetic marker that can distinguish between Atlantic salmon (Salmo salar) of European and North American origin is described. Screening of 2847 European and 247 North American Atlantic salmon from much of its geographic range for variability at a minisatellite locus, Ssa-A45/2/2, revealed the continental stocks to be almost fixed for two different-sized, easily discernable alleles. Virtually all European Atlantic salmon were homozygous for a 3.00-kb allele (frequency > 0.999), while a smaller 2.77-kb allele (frequency = 0.946) predominated in all North American populations. Whereas the 2.77-kb allele was found exclusively in North American salmon, an allele indistinguishable in size from the 3.00-kb European diagnostic allele was also observed at low frequency (0.036) in North American fish. Eight other continent-specific rare alleles (highest frequency = 0.006) were also observed. The results suggest that little, if any, natural gene flow occurs between the two continental groups of Atlantic salmon.

Spawning of Escaped Farmed Atlantic Salmon (Salmo salar): Hybridization of Females with Brown Trout (Salmo trutta)

1993 ◽  
Vol 50 (9) ◽  
pp. 1986-1990 ◽  
Author(s):  
A. F. Youngson ◽  
J. H. Webb ◽  
C. E. Thompson ◽  
D. Knox
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Brown Trout ◽  
Salmo Trutta ◽  
F1 Hybrids ◽  
Fish Farms ◽  
Atlantic Salmon Salmo Salar ◽  
Brown Trout Salmo Trutta ◽  
The Difference ◽  
Farmed Atlantic Salmon

Atlantic salmon (Salmo salar) and F1 hybrids between Atlantic salmon and brown trout (Salmo trutta) were distinguished among juvenile salmonids sampled at emergence from rivers in western and northern Scotland. Hybrids were present in samples obtained from seven of the 16 rivers examined. Salmon fry and hybrid fry that were demonstrably the progeny of female salmon that had escaped from fish farms were identified by detecting the presence of maternal canthaxanthin, a synthetic flesh colorant, in the juveniles' pigment load. Canthaxanthin was detected in 101 (4%) of the 2350 salmon and eight (35%) of the 23 hybrids examined. The difference in the frequencies of salmon and hybrids carrying canthaxanthin was significant. Escaped female salmon hybridized with trout more frequently than did wild females.

Evidence for sea lice-induced marine mortality of Atlantic salmon (Salmo salar) in western Ireland from experimental releases of ranched smolts treated with emamectin benzoate

2012 ◽  
Vol 69 (2) ◽  
pp. 343-353 ◽  
Author(s):  
P.G. Gargan ◽  
G. Forde ◽  
N. Hazon ◽  
D.J.F. Russell ◽  
C.D. Todd
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Salmo Trutta ◽  
Conservation Status ◽  
Sea Lice ◽  
Control Fish ◽  
Emamectin Benzoate ◽  
Sea Trout ◽  
Atlantic Salmon Salmo Salar ◽  
Western Ireland

Sea trout ( Salmo trutta ) stock collapses in coastal areas of western Ireland subject to salmon aquaculture were contemporaneous with high abundances of larval sea lice ( Lepeophtheirus salmonis ) on juvenile sea trout. Whereas sea trout remain in near-shore waters throughout their marine migration, Atlantic salmon ( Salmo salar ) smolts typically move quickly offshore into oceanic waters. It might therefore be predicted that salmon smolts would be less vulnerable to coastal stressors and less likely to be negatively affected by infestations of sea lice early in their marine phase. Groups of microtagged, hatchery-reared Atlantic salmon smolts were fed either untreated pellets or pellets incorporating the in-feed sea louse treatment SLICE (emamectin benzoate) prior to eight experimental releases in three marine locations over a 3-year period. In total, 74 324 smolts were released and analysis of tag recaptures from returning adult salmon showed that emamectin-treated smolts experienced increased survivorship and were 1.8 times more likely to return compared with control fish. These results suggest that sea lice-induced mortality on adult Atlantic salmon returns in Ireland can be significant, and that sea lice larvae emanating from farmed salmon may influence individual survivorship and population conservation status of wild salmon in these river systems.

Effects of habitat on individual reproductive success of mature male parr of Atlantic salmon Salmo salar

2010 ◽  
Vol 77 (10) ◽  
pp. 2460-2466 ◽  
Author(s):  
D. Grimardias ◽  
N. Merchermek ◽  
A. Manicki ◽  
J. Chebaux ◽  
P. Gaudin ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Mature Male ◽  
Atlantic Salmon Salmo Salar ◽  
Mature Male Parr
Sign in / Sign up

Export Citation Format

Share Document