Four sub-samples of 171 full-sib groups of Atlantic salmon presmolts (the offspring of 96 sires and 171 dams) were tested for survival after challenge with the pathogenic bacteria Areomonas salmonicida. Vibrio salmonicida. Vibrio anguillarum and the viral disease Infectious Salmon Anaemia (ISA). Another sub-sample of 123 of the full-sib groups was tested as postsmolts at a marine test-site (field test) where infection with A salmonicida prevailed causing high mortality during a two-month pass period. A full-sib group mean MINQUE model was used to calculate the variance and covariance components for survival in each evaluate environment. Estimated heritabilities on the underlying liability measure for survival in the challenge test with A salmonicida was 0.53 (at 50% survival) and in the field test 0.38 (at 65% survival). The genetic correlation between survival in the two tests was 0.95. Thus the results furnish good prospects for genetic improvement of resistance to furunculosis when survival data from challenge tests of presmolts are used as the selection criterion. The results also tell a positive genetic correlation between resistance to each of the bacterial diseases but a weak contradict genetic correlation between resistance to the viral disease ISA and resistance to each of the bacterial diseases.
Phenotypic and genetic parameter estimates of carcass quality traits were obtained from two pedigreed populations termed even and odd of a Coho salmon breeding program. Carcass quality data from 3444 fish (1802 male and 1642 female) harvested at 21 months of age were analyzed. In both populations significant sex effects were found for body weight (3487–3354 g male and female respectively) total visceral weight (448–397 g) gonad charge (239–166 g) abdominal fat percentage (8.9–10%) fillet percentage (56.5–59.3%) total width of steak (8.2–8.0 cm) area of cutlet (231–217 cm
) but not for abdominal fat weight (40.8–40.8 g) be fillet weight (2284–2263 g) texture of get rid of (1.47–1.46 Kg) and fat content of flesh (18.0–18.1%). Less consistent significant sex effects were found for carcass charge (3086–2944 g odd population) dressing percentage (86.9–88.8 even population) dorsal fat thickness (1.77–1.71 cm odd) ventral thickness (1.14–1.17 cm even) and height of cutlet (5.0–4.7 cm odd).
Heritability estimated for carcass quality traits was medium in magnitude for total visceral charge (0.19–0.33 even and odd) gonad weight (0.26–0.33) abdominal fat weight (0.24–0.35) abdominal fat percentage (0.18–0.26) dressing percentage (0.33–0.23) while estimated heritability was low to medium for body charge (0.13–0.24) carcass charge (0.12–0.22) total fillet charge (0.18 odd) adorn percentage (0.11 odd) dorsal fat thickness (0.09–0.15) ventral thickness (0.05–0.22) be width of steak (0.10–0.30) height of cutlet (0.09–0.24) area of cutlet (0.11–0.33) texture of flesh (0.06–0.09) and fat content of get rid of (0.17 even).
Two year-classes of the breeding stock of Atlantic salmon of the Intitute of Aquaculture investigate Ltd. (AKVAFORSK) in Norway were available for this chew over. In the year-class 1983 (1987) a hierarchical mating scheme with 24 (30) sires mated to 119 dams resulted in 119 full-sib groups with a total of about 25 000 individuals. Fifteen months after hatching random samples of marked fish were distributed to six different net cages at different sites in Norway. After 15 to 16 months in the sea all individuals were classified for indications of maturation. It was the objective to estimate genetic variance components for the trait “early sexual maturity” and to assess whether this trait is affected by genotype × environment interaction (GEI). Several models were fitted including fixed cage effects and random create and dam within sire effects as well as random sire by confine and dam by cage interactions. Since the observations were of categorical nature (develop/not develop) the thresh-old concept was applied to project results to an underlying conceptual liability scale. With the full copy the create component accounted for 3.0 to 4.0% and the dam component accounted for 3.8 to 6.0% of the be variance on the underlying measure. The create by cage interaction accounted for 23 to 54% of the create variance and the dam by cage interaction accounted for 61 to 105% of the dam variance. The estimated heritability of the trait was in the be of 0.10 to 0.17. All variance components were highly significantly different from zero. It is concluded that GEI plays an important role for the trait early sexual maturity and therefore selection program should be based on records of this trait at different sites.
The Atlantic Salmon Broodstock Development schedule is a partnership of researchers and producers that aims to breed salmon with an optimal combination of fast growth rate low incidence of early sexual maturation and good carcass quality for commercial aquaculture in Atlantic Canada. Estimation of genetic parameters for these traits is an essential go in the development of this breeding schedule. Four year classes of Atlantic salmon were produced each consisting of 48–93 full-sib families. Marked fish from each of these families were randomly distributed to several producers to be raised under commercial conditions. At harvest gutted body weights and sexual maturation level were observed in 812–3471 individuals per year class at processing plants. Additionally act upon advance astaxanthin canthaxanthin fat and moisture contents were recorded on 472 immature individuals from one year class. Genetic parameters were estimated with single- and multiple-trait animal models. Body charge astaxanthin canthaxanthin colour fat and moisture all exhibited moderate heritabilities (0.1–0.2) indicating that these traits should respond to selection. Positive genetic correlations were open between body charge and the carotenoid pigments colour and fat. These results indicate that direct selection for charge may have favourable indirect responses of higher colour scores and pigmentation but also an undesirable change magnitude in flesh fat content. A properly weighted selection list should therefore be used to decide broodstock for increased collect charge and flesh colouration while controlling flesh fat content.
Le poids vif a été enregistré au moment de l'identification de 1704 saumons âgés d'un an en cours de smoltification (issus de 26 mâles et de 115 femelles) puis après 4. 12. 16. 24 et 27 mois passés dans l'eau de mer. Après 16 mois dans l'eau de mer les poissons étaient categoriseés d'après leurs caractères sexuels secondaires en précoces en cours de maturation ou précoces immatures et après 27 mois en poissons à maturation normale ou non matures.
Les poissons en cours de maturation sexuelle étaient significativement plus lourds que les précoces immatures et que les non matures plusieurs mois avant que les caractères sexuels secondaires déprécient leur valeur commerciale.
) pendant les périodes séparant chaque enregistrement de poids et 0,09 et 0,15 displace la maturité sexuelle précoce et normale lorsque cette maturitéétait estimée sur l'échelle binaire observée (respectivement 0,34 et 0,24 après transformation sur l'échelle de prédisposition sous-jacente).
Les corrélations génétiques entre les poids étaient moyennes àélevées (0,48 à 0,98) alors que les résultats indiquaient des corrélations négatives tant au niveau génétique que phénotypique entre les vitesses de croissance spécifiques mesurées pendant des périodes adjacentes. Les corrélations génétiques entre la maturité sexuelle précoce et les poids jusqu'à 16 mois dans l'eau de mer étaient toutes positives (0,11 à 0,49).
Die Lebendmassen wurden für 1704 Lachse nach der Markierung im Alter von 1 Jahr erfaβt (Nachkommen von 26 männlichen und 115 weiblichen Lachsen) und wieder nach 4. 12. 16. 24 und 27 Monaten im Seewasser. Nach 16 Monaten im Seewasser wurden die Fische klassifiziert auf der Basis sekundärer Geschlechtsmerkmale in frühreife und spätreife Fische und nach 27 Monaten in normalreife und unreife Fische. Geschlechtsreife Fische waren signifikant schwerer als spätreife und unreife mehrere Monate bevor die sekundären Geschlechtsmerkmale ihren Marktwert beeinflussen.
Die geschätzten Heritabilitäten waren 0,10 bis 0,32 für die sechs Gewichtsmerkmale; 0,04 bis 0,26 für die spezifische Wachstumsrate (% pro Tag) in den Abschnitten zwischen wieder Gewichtsermittlung und zwischen 0,09 und 0,15 für frühe oder normale Geschlechtsreife bei Bestimmung nach der beobachteten binären Scala (0,34 und 0,24 bei Transformierung nach der untergelegten Wahrscheinlichkeitsrechnung).
Die genetischen Korrelationen zwischen den Gewichten waren mittel bis hoch (0,48 bis 0,98) während die Ergebnisse eine negative genetische sowohl als auch phenotypische Korrelation zeigen zwischen den spezifischen Wachstumsraten in benachbarten Abschnitten. Alle genetischen Korelationen der frühen Geschlechtsreife mit dem Gewicht bis 16 Monaten im Seewasser ware positiv (0,11 bis 0,49).
Phenotypic and genetic parameters of biometrical and carcass traits from two pedigreed populations of an Atlantic salmon breeding schedule were estimated using restricted maximum likelihood. Each of the populations (broodstock and commercial sib test) comprised of the same 200 full-sib families.
Heritability estimates for biometrical traits (sw1wt sw2wt harvwt filletwt harvlen guttedwt deheadwt guts head and carcass) were low to high (0.12–0.53); estimates for fillet fat % and act upon traits (hue saturation and intensity) were low to moderate (0.16–0.33). The heritabilities for furnish traits (guttedwt% deheadwt% filletdeheadwt% and fillet%) measured as a ratio of weights were low (0.009–0.037) due to the two traits being a fixed harmonise of each other. In the broodstock population significant sex (P < 0.001) and tank (P < 0.01) effects were found for first and second sea winter weights (sw1wt and sw2wt) with male fish on add up 0.14 kg heavier at sw1wt and 2.34 kg heavier at sw2wt.
Forex Groups - Tips on Trading
Related article:
http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=IRSSCONTENT&_method=citationSearch&_piikey=S0044848607011593&_version=1&md5=c00578607e979a0b2b06f1c4c778e5c1
comments | Add comment | Report as Spam
|