The Experts below are selected from a list of 3285 Experts worldwide ranked by ideXlab platform
Christopher J Donohoe - One of the best experts on this subject based on the ideXlab platform.
-
identifying the contribution of wild and hatchery chinook salmon oncorhynchus tshawytscha to the ocean fishery using otolith microstructure as natural tags
Canadian Journal of Fisheries and Aquatic Sciences, 2007Co-Authors: Rachel Barnettjohnson, Churchill B Grimes, Chantell F Royer, Christopher J DonohoeAbstract:Quantifying the contribution of wild (naturally spawned) and hatchery Chinook salmon (Oncorhynchus tshawytscha) to the mixed-stock ocean fishery is critical to understanding their relative importance to the persistence of salmon stocks. The inability to distinguish hatchery and wild salmon has inhibited the detection of declines or recover- ies for many wild populations. By using Chinook salmon of known hatchery and wild origin, we established a baseline for separating these two sources using otolith microstructure. Otoliths of wild salmon contained a distinct exogenous feeding check likely reflecting an abrupt transition in food resources from maternal yolk not experienced by fish reared in hatcheries. Daily growth increments in otoliths from hatchery salmon immediately after the onset of exogenous feed- ing were wider and more uniform in width than those in wild fish. The discriminant function that we used to distin- guish individuals reared in hatcheries or in the wild was robust between years (1999 and 2002), life history stages (juveniles and adults), and geographic regions (California, British Columbia, and Alaska) and classified fish with ~91% accuracy. Results from our mixed-stock model estimated that the contribution of wild fish was 10% ± 6%, indicating hatchery supplementation may be playing a larger role in supporting the central California coastal fishery than previ- ously assumed. Resume : La mesure des contributions des saumons chinook (Oncorhynchus tshawytscha) reproduits en nature (sauva- ges) et en Pisciculture a la peche commerciale marine de stock mixte est essentielle pour comprendre leur importance relative dans la persistance des stocks de saumons. L'impossibilite de distinguer entre les saumons de Pisciculture et les saumons sauvages a empeche la detection des declins et des recuperations chez de nombreuses populations sauvages. En utilisant des saumons chinook d'origine connue en nature ou en Pisciculture, nous avons etabli des criteres de base pour separer les deux sources d'apres la microstructure des otolithes. Les otolithes des saumons sauvages portent une marque distincte exogene d'alimentation qui reflete sans doute une transition abrupte dans les ressources alimentaires apres l'epuisement du jaune d'oeuf maternel, ce qui ne survient pas chez les poissons eleves en Pisciculture. Les zones de croissance journaliere dans les otolithes des saumons de Pisciculture immediatement apres le debut de l'alimentation exogene sont plus larges et d'epaisseur plus uniforme que celles des poissons sauvages. La fonction discriminante que nous utilisons pour distinguer les individus eleves en Pisciculture et en nature est robuste en fonction des annees (1999 et 2002), des stades du cycle biologique (jeunes et adultes) et des regions geographiques (Californie, Colombie-
Michael S. Blouin - One of the best experts on this subject based on the ideXlab platform.
-
No evidence for large differences in genomic methylation between wild and hatchery steelhead (Oncorhynchus mykiss)
Canadian Journal of Fisheries and Aquatic Sciences, 2010Co-Authors: Michael S. Blouin, Virginie Thuillierv. Thuillier, Becky Cooper, Vindhya Amarasinghe, Laura Cluzell. Cluzel, Hitoshi Araki, Christoph Grunauc. GrunauAbstract:When salmonid fish that have been raised in hatcheries spawn in the wild, they often produce fewer surviving adult offspring than wild fish. Recent data from steelhead (Oncorhynchus mykiss) in the Hood River (Oregon, USA) show that even one or two generations of hatchery culture can result in dramatic declines in fitness. Although intense domestica- tion selection could cause such declines, it is worth considering alternative explanations. One possibility is heritable epige- netic changes induced by the hatchery environment. Here, we show, using methylation-sensitive amplified fragment length polymorphism, that hatchery and wild adult steelhead from the Hood River do not appear to differ substantially in overall levels of genomic methylation. Thus, although altered methylation of specific DNA sites or other epigenetic processes could still be important, the hatchery environment does not appear to cause a global hypo- or hypermethylation of the ge- nome or create a large number of sites that are differentially methylated. Resume´ : Lorsque des poissons salmonideseleves en Pisciculture se reproduisent en nature, ils produisent souvent moins de rejetons survivants que les poissons sauvages. Des donnees recentes sur la truite arc-en-ciel anadrome (Oncorhynchus mykiss) dans la riviere Hood (Oregon, E ´ .-U.) montrent que meme une ou deux generations en Pisciculture peuvent en- traoˆner des reductions spectaculaires de fitness. Bien qu'une selection intense relieeala domestication puisse causer de tels declins, il est important d'examiner les hypotheses de rechange. Parmi les possibilites, il y a les changements epigene ´- tiques heritables causes par l'environnement de Pisciculture. Nous montrons ici, al'aide du polymorphisme de la longueur des fragments amplifies sensible a la methylation, que les truites arc-en-ciel anadromes de Pisciculture et les truites sau- vages de la Hood ne semblent pas differer de maniere importante dans leurs niveaux globaux de methylation genomique. Ainsi, alors que la methylation alteree de certains sites d'ADN ou d'autres processus epigenetiques pourraient quand meme etre importants, le milieu de Pisciculture ne semble causer ni une hypo-, ni une hyper-methylation globale du ge ´- nome, ni creer un nombre elevede sites amethylation distincte. (Traduit par la Redaction)
-
The influence of family-correlated survival on Nb/N for progeny from integrated multi- and single-generation hatchery stocks of coho salmon (Oncorhynchus kisutch)
Canadian Journal of Fisheries and Aquatic Sciences, 2007Co-Authors: Gregory R. Moyer, Michael S. Blouin, Michael A. BanksAbstract:There exist surprisingly few data on the final variance and mean of family sizes for hatchery-born fish at the adult stage. Thus, it is difficult to predict, for a conservation hatchery operation that minimizes the variance in progeny number, how much lower the true effective population size (Ne) of a cohort of hatchery-born adults will be than Ne predicted simply by the number of parents that produced them. We used parentage analysis to estimate the survival and Ne for two integrated stocks of hatchery coho salmon (Oncorhynchus kisutch). One hatchery is a multigeneration stock obtained by spawning 70% hatchery with 30% naturally reproducing fish, whereas the second is a single-generation stock derived from naturally reproducing coho. There was no significant difference in average overall survival between stocks, but observed Ne was significantly less than expected for each stock. Family-correlated survival contributed to roughly a 20% reduction in Ne over the freshwater and marine life stages. This reduction is similar to previous esti- mates and suggests a value that can be used when estimating the effective number of hatchery parents in applications of the Ryman-Laikre formula (at least for programs such as ours that attempt to equalize sex ratios and family sizes). Resume : Il existe etonnamment peu de donnees sur la variance et la moyenne finales des tailles des familles au stade adulte chez les poissons nes en Pisciculture. Il est ainsi difficile, dans une Pisciculture de conservation qui minimise la va- riance des nombres dans la progeniture, de predire de combien inferieure sera la veritable taille effective de la population (Ne) d'une cohorte d'adultes nes en Pisciculture par rapport au Ne predit simplement par le nombre des parents qui les ont produits. Nous utilisons une analyse de parente pour estimer la survie et le Ne chez deux stocks integres de saumons coho (Oncorhynchus kisutch) de Pisciculture. Une des Piscicultures utilise un stock de plusieurs generations obtenu en croisant 70 % de poissons de Pisciculture avec 30 % de poissons a reproduction naturelle, alors que l'autre est forme d'un seul stock de saumons coho a reproduction naturelle. Il n'y a pas de difference de survie globale entre les stocks, mais le Ne observe est significativement inferieur a la valeur attendue pour chacun des stocks. La survie en fonction de la famille contribue grosso modo 20 % de la reduction de Ne au cours des stades du cycle en eau douce et en mer. Cette reduction est semblable a celle des estimations anterieures, ce qui fournit une valeur qui peut etre utilisee pour calculer le nombre effectif de parents de Pisciculture lors de l'application de la formule de Ryman-Laikre (au moins dans les programmes comme le notre qui cherchent a egaliser les rapports mâles-femelles et les tailles des familles). (Traduit par la Redaction) Moyer et al. 1265
John E Joyce - One of the best experts on this subject based on the ideXlab platform.
-
variation of agonistic behavior among juvenile chinook salmon oncorhynchus tshawytscha of hatchery hybrid and wild origin
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Maria Lang Wessel, William W Smoker, Robert Fagen, John E JoyceAbstract:Agonistic behavior and ability to dominate were compared among juveniles from a hatchery stock of Chi- nook salmon (Oncorhynchus tshawytscha) that has experienced five generations of hatchery culture, juveniles derived from the wild founding stock but produced from parents cultured in the same hatchery environment as the hatchery stock, and second-generation hybrids between the two lines. Equal numbers of parr (18) from equal numbers of fami- lies (5) from each fish line (3) were tested, and all lines were raised in a similar hatchery environment. During 20 min of observation in replicate artificial stream tanks, hatchery-derived fish made significantly greater numbers of charges, displays, and nips than wild-derived fish. Hybrids also made significantly greater numbers of charges, displays, and nips than wild-derived fish but significantly fewer displays than hatchery-derived fish. No difference was detected in the ability of fish lines to win dyadic dominance contests. These results suggest that the differences detected are ge- netic in origin and are consistent with divergence of the hatchery stock from the founding wild stock. Resume : Nous avons compare le comportement agoniste et l'habilete a dominer chez des jeunes d'un stock de pisci- culture de saumons quinnat (Oncorhynchus tshawytscha) qui a connu cinq generations d'elevage en Pisciculture, chez des jeunes issus du stock fondateur sauvage, mais nes de parents eleves dans le meme milieu de Pisciculture que le stock de Pisciculture et chez des hybrides de seconde generation issus des deux lignees. Nous avons evalue des nom- bres egaux de tacons (18) d'un meme nombre de familles (5) de chaque lignee de poissons (3) et toutes les lignees ont ete elevees dans un meme environnement de Pisciculture. Lors d'observations de 20 min dans des bassins artificiels ap- paries, les poissons provenant de la Pisciculture font significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons issus du stock sauvage. Les hybrides font aussi significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons d'origine sauvage, mais significativement moins de pri- ses de position de bravade que les poissons de Pisciculture. Il n'y a pas de difference entre l'habilete des differentes lignees de poissons a gagner des epreuves dyadiques de dominance. Ces resultats laissent croire que les differences observees sont d'origine genetique et qu'elles s'accordent avec une divergence du stock de Pisciculture a partir du stock fondateur sauvage. (Traduit par la Redaction) Wessel et al. 447
-
Variation of agonistic behavior among juvenile Chinook salmon (Oncorhynchus tshawytscha) of hatchery, hybrid, and wild origin
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Maria Lang Wessel, William W Smoker, Robert Fagen, John E JoyceAbstract:Agonistic behavior and ability to dominate were compared among juveniles from a hatchery stock of Chi- nook salmon (Oncorhynchus tshawytscha) that has experienced five generations of hatchery culture, juveniles derived from the wild founding stock but produced from parents cultured in the same hatchery environment as the hatchery stock, and second-generation hybrids between the two lines. Equal numbers of parr (18) from equal numbers of fami- lies (5) from each fish line (3) were tested, and all lines were raised in a similar hatchery environment. During 20 min of observation in replicate artificial stream tanks, hatchery-derived fish made significantly greater numbers of charges, displays, and nips than wild-derived fish. Hybrids also made significantly greater numbers of charges, displays, and nips than wild-derived fish but significantly fewer displays than hatchery-derived fish. No difference was detected in the ability of fish lines to win dyadic dominance contests. These results suggest that the differences detected are ge- netic in origin and are consistent with divergence of the hatchery stock from the founding wild stock. Resume : Nous avons compare le comportement agoniste et l'habilete a dominer chez des jeunes d'un stock de pisci- culture de saumons quinnat (Oncorhynchus tshawytscha) qui a connu cinq generations d'elevage en Pisciculture, chez des jeunes issus du stock fondateur sauvage, mais nes de parents eleves dans le meme milieu de Pisciculture que le stock de Pisciculture et chez des hybrides de seconde generation issus des deux lignees. Nous avons evalue des nom- bres egaux de tacons (18) d'un meme nombre de familles (5) de chaque lignee de poissons (3) et toutes les lignees ont ete elevees dans un meme environnement de Pisciculture. Lors d'observations de 20 min dans des bassins artificiels ap- paries, les poissons provenant de la Pisciculture font significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons issus du stock sauvage. Les hybrides font aussi significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons d'origine sauvage, mais significativement moins de pri- ses de position de bravade que les poissons de Pisciculture. Il n'y a pas de difference entre l'habilete des differentes lignees de poissons a gagner des epreuves dyadiques de dominance. Ces resultats laissent croire que les differences observees sont d'origine genetique et qu'elles s'accordent avec une divergence du stock de Pisciculture a partir du stock fondateur sauvage. (Traduit par la Redaction) Wessel et al. 447
Christoph Grunauc. Grunau - One of the best experts on this subject based on the ideXlab platform.
-
No evidence for large differences in genomic methylation between wild and hatchery steelhead (Oncorhynchus mykiss)
Canadian Journal of Fisheries and Aquatic Sciences, 2010Co-Authors: Michael S. Blouin, Virginie Thuillierv. Thuillier, Becky Cooper, Vindhya Amarasinghe, Laura Cluzell. Cluzel, Hitoshi Araki, Christoph Grunauc. GrunauAbstract:When salmonid fish that have been raised in hatcheries spawn in the wild, they often produce fewer surviving adult offspring than wild fish. Recent data from steelhead (Oncorhynchus mykiss) in the Hood River (Oregon, USA) show that even one or two generations of hatchery culture can result in dramatic declines in fitness. Although intense domestica- tion selection could cause such declines, it is worth considering alternative explanations. One possibility is heritable epige- netic changes induced by the hatchery environment. Here, we show, using methylation-sensitive amplified fragment length polymorphism, that hatchery and wild adult steelhead from the Hood River do not appear to differ substantially in overall levels of genomic methylation. Thus, although altered methylation of specific DNA sites or other epigenetic processes could still be important, the hatchery environment does not appear to cause a global hypo- or hypermethylation of the ge- nome or create a large number of sites that are differentially methylated. Resume´ : Lorsque des poissons salmonideseleves en Pisciculture se reproduisent en nature, ils produisent souvent moins de rejetons survivants que les poissons sauvages. Des donnees recentes sur la truite arc-en-ciel anadrome (Oncorhynchus mykiss) dans la riviere Hood (Oregon, E ´ .-U.) montrent que meme une ou deux generations en Pisciculture peuvent en- traoˆner des reductions spectaculaires de fitness. Bien qu'une selection intense relieeala domestication puisse causer de tels declins, il est important d'examiner les hypotheses de rechange. Parmi les possibilites, il y a les changements epigene ´- tiques heritables causes par l'environnement de Pisciculture. Nous montrons ici, al'aide du polymorphisme de la longueur des fragments amplifies sensible a la methylation, que les truites arc-en-ciel anadromes de Pisciculture et les truites sau- vages de la Hood ne semblent pas differer de maniere importante dans leurs niveaux globaux de methylation genomique. Ainsi, alors que la methylation alteree de certains sites d'ADN ou d'autres processus epigenetiques pourraient quand meme etre importants, le milieu de Pisciculture ne semble causer ni une hypo-, ni une hyper-methylation globale du ge ´- nome, ni creer un nombre elevede sites amethylation distincte. (Traduit par la Redaction)
Maria Lang Wessel - One of the best experts on this subject based on the ideXlab platform.
-
variation of agonistic behavior among juvenile chinook salmon oncorhynchus tshawytscha of hatchery hybrid and wild origin
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Maria Lang Wessel, William W Smoker, Robert Fagen, John E JoyceAbstract:Agonistic behavior and ability to dominate were compared among juveniles from a hatchery stock of Chi- nook salmon (Oncorhynchus tshawytscha) that has experienced five generations of hatchery culture, juveniles derived from the wild founding stock but produced from parents cultured in the same hatchery environment as the hatchery stock, and second-generation hybrids between the two lines. Equal numbers of parr (18) from equal numbers of fami- lies (5) from each fish line (3) were tested, and all lines were raised in a similar hatchery environment. During 20 min of observation in replicate artificial stream tanks, hatchery-derived fish made significantly greater numbers of charges, displays, and nips than wild-derived fish. Hybrids also made significantly greater numbers of charges, displays, and nips than wild-derived fish but significantly fewer displays than hatchery-derived fish. No difference was detected in the ability of fish lines to win dyadic dominance contests. These results suggest that the differences detected are ge- netic in origin and are consistent with divergence of the hatchery stock from the founding wild stock. Resume : Nous avons compare le comportement agoniste et l'habilete a dominer chez des jeunes d'un stock de pisci- culture de saumons quinnat (Oncorhynchus tshawytscha) qui a connu cinq generations d'elevage en Pisciculture, chez des jeunes issus du stock fondateur sauvage, mais nes de parents eleves dans le meme milieu de Pisciculture que le stock de Pisciculture et chez des hybrides de seconde generation issus des deux lignees. Nous avons evalue des nom- bres egaux de tacons (18) d'un meme nombre de familles (5) de chaque lignee de poissons (3) et toutes les lignees ont ete elevees dans un meme environnement de Pisciculture. Lors d'observations de 20 min dans des bassins artificiels ap- paries, les poissons provenant de la Pisciculture font significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons issus du stock sauvage. Les hybrides font aussi significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons d'origine sauvage, mais significativement moins de pri- ses de position de bravade que les poissons de Pisciculture. Il n'y a pas de difference entre l'habilete des differentes lignees de poissons a gagner des epreuves dyadiques de dominance. Ces resultats laissent croire que les differences observees sont d'origine genetique et qu'elles s'accordent avec une divergence du stock de Pisciculture a partir du stock fondateur sauvage. (Traduit par la Redaction) Wessel et al. 447
-
Variation of agonistic behavior among juvenile Chinook salmon (Oncorhynchus tshawytscha) of hatchery, hybrid, and wild origin
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Maria Lang Wessel, William W Smoker, Robert Fagen, John E JoyceAbstract:Agonistic behavior and ability to dominate were compared among juveniles from a hatchery stock of Chi- nook salmon (Oncorhynchus tshawytscha) that has experienced five generations of hatchery culture, juveniles derived from the wild founding stock but produced from parents cultured in the same hatchery environment as the hatchery stock, and second-generation hybrids between the two lines. Equal numbers of parr (18) from equal numbers of fami- lies (5) from each fish line (3) were tested, and all lines were raised in a similar hatchery environment. During 20 min of observation in replicate artificial stream tanks, hatchery-derived fish made significantly greater numbers of charges, displays, and nips than wild-derived fish. Hybrids also made significantly greater numbers of charges, displays, and nips than wild-derived fish but significantly fewer displays than hatchery-derived fish. No difference was detected in the ability of fish lines to win dyadic dominance contests. These results suggest that the differences detected are ge- netic in origin and are consistent with divergence of the hatchery stock from the founding wild stock. Resume : Nous avons compare le comportement agoniste et l'habilete a dominer chez des jeunes d'un stock de pisci- culture de saumons quinnat (Oncorhynchus tshawytscha) qui a connu cinq generations d'elevage en Pisciculture, chez des jeunes issus du stock fondateur sauvage, mais nes de parents eleves dans le meme milieu de Pisciculture que le stock de Pisciculture et chez des hybrides de seconde generation issus des deux lignees. Nous avons evalue des nom- bres egaux de tacons (18) d'un meme nombre de familles (5) de chaque lignee de poissons (3) et toutes les lignees ont ete elevees dans un meme environnement de Pisciculture. Lors d'observations de 20 min dans des bassins artificiels ap- paries, les poissons provenant de la Pisciculture font significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons issus du stock sauvage. Les hybrides font aussi significativement plus d'avancees, de prises de position de bravade et de picotages que les poissons d'origine sauvage, mais significativement moins de pri- ses de position de bravade que les poissons de Pisciculture. Il n'y a pas de difference entre l'habilete des differentes lignees de poissons a gagner des epreuves dyadiques de dominance. Ces resultats laissent croire que les differences observees sont d'origine genetique et qu'elles s'accordent avec une divergence du stock de Pisciculture a partir du stock fondateur sauvage. (Traduit par la Redaction) Wessel et al. 447