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Development Of Nuclear Dna Markers To Detect Hybridization And Assess Phylogenetic Relationships Among Subspecies Of Rainbow Trout Oncorhynchus Mykiss And Cutthroat Trout Oncorhynchus Clarki
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Book Synopsis Development of Nuclear DNA Markers to Detect Hybridization and Assess Phylogenetic Relationships Among Subspecies of Rainbow Trout (Oncorhynchus Mykiss) and Cutthroat Trout (Oncorhynchus Clarki) by : J. W. Pearce Smithwick
Download or read book Development of Nuclear DNA Markers to Detect Hybridization and Assess Phylogenetic Relationships Among Subspecies of Rainbow Trout (Oncorhynchus Mykiss) and Cutthroat Trout (Oncorhynchus Clarki) written by J. W. Pearce Smithwick and published by . This book was released on 2000 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Single Nucleotide Polymorphisms in the Hsp30 Gene as Markers to Detect Oncohynchus Mykiss (rainbow Trout) and Oncorhynchus Clarkii (cutthroat Trout) Hybridization by : Rebecca L. Loda
Download or read book Single Nucleotide Polymorphisms in the Hsp30 Gene as Markers to Detect Oncohynchus Mykiss (rainbow Trout) and Oncorhynchus Clarkii (cutthroat Trout) Hybridization written by Rebecca L. Loda and published by . This book was released on 2004 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Hybridization with introduced rainbow trout has been a formidable barrier to conservation and re-introduction of native species of cutthroat trout in the inter mountain west, including the Truckee River system. To aid in the management of native cutthroat trout, a reliable test needs to be developed to identify and monitor hybrids. Genetic analysis of microsatellites has been employed for hybrid detection, but the high degree of inter- and intra- species variability at these loci limits this approach to specific strains of trout. Because of the amount of genetic variation between subspecies of trout, additional markers are desirable for robust identification of hybrids ... To test the possibility of using genetic variation within the HSP30 locus as markers to detect rainbow trout and cutthroat trout hybrids, DNA from Greenback, Lahontan, Colorado River, Bonneville, Coastal, Yellowstone, Westslope, and Snake River cutthroat trout and four strains of rainbow trout was amplified by PCR and sequenced. Consensus sequences and sequence alignments were produced for each species or subspecies, and the data were analyzed to identify single nucleotide polymorphisms (SNPs) that showed species-specific variation. Four polymorphic loci were identified that allow distinction between rainbow trout and seven of the of the eight cutthroat subspecies. Primers pairs were designed to allow species identification without the need for sequencing, using SNPs in the HSP30 gene for the identification of rainbow/cutthroat hybrids and also hybridization between different strains of cutthroat and cutthroat/rainbow hybrids using high throughput sequencing. We were able to design a primer pair that could distinguish rainbow and cutthroat trout using only PCR. However, additional primers must be developed that can identify cutthroat/rainbow hybrids without sequence analysis."--Abstract.
Book Synopsis Genomic Consequences of Hybridization Between Rainbow and Cutthroat Trout by : Carl O. Ostberg
Download or read book Genomic Consequences of Hybridization Between Rainbow and Cutthroat Trout written by Carl O. Ostberg and published by . This book was released on 2015 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introgressive hybridization creates novel gene combinations that may generate important evolutionary novelty and thus contribute to biological complexity and diversification. On the other hand, hybridization with introduced species can threaten native species, such as cutthroat trout (Oncorhynchus clarkii) following the introduction of rainbow trout (O. mykiss). While rainbow trout introgression in cutthroat trout is well documented, neither the evolutionary consequences nor conservation implications are well understood. Hybridization between rainbow and cutthroat trout occurs in the context of substantial chromosomal rearrangement, as well incompletely re-diploidized genomes. Rainbow and cutthroat trout are descended from an autopolyploid ancestor, and extensive chromosome arm rearrangements have occurred between the species following their divergence from the last common ancestor. Evidence for incomplete re-diploidization includes the occasional formation of multivalents and duplicated loci occasionally exhibit a mixture of disomic and tetrasomic inheritance. Thus, transmission genetics may be complicated by recombination between homeologs. Here, I evaluated the phenotypic and genetic consequences of introgression between rainbow trout and Yellowstone cutthroat trout (O. clarkii bouvieri) to provide insights into genome processes that may help explain how introgression affects hybrid genome evolution. The overall aim of the first part of this dissertation (Chapters 1 and 2) was to evaluate phenotypic variation and gene expression among parental species and hybrids to gain insight into the genetic basis of hybrid and parental morphologies. We constructed seven line crosses: both parental species, both reciprocal F1 hybrids, first-generation backcrosses, and F2 hybrids. In Chapter 1, we aimed to assess the role of introgression on growth (length and weight gain), morphology, and developmental instability among these seven crosses. Growth was related to the proportion of rainbow trout genome contained within crosses. Rainbow and cutthroat trout were morphologically divergent: rainbow trout were generally robust whereas cutthroat trout were typically more slender and their hybrids tended to be morphologically intermediate, although backcrosses were morphologically more similar to their backcrossing parental species. These differences in growth and body morphology may be maintained, in part, through the regulation of muscle growth-related genes. Therefore, in Chapter 2, we aimed to characterize the expression of muscle growth-related genes and to describe relationships between gene expression and growth patterns among parental species and hybrids to gain insight into the underlying genetic basis of the difference in their body shapes. Our findings suggest that rainbow and cutthroat trout exhibit differences in muscle growth regulation, that transcriptional networks may be modified by hybridization, and that hybridization disrupts intrinsic relationships between gene expression and growth patterns that may be functionally important for phenotypic adaptations. The overall aim of the second part of this dissertation (Chapters 3 and 4) was to assess the genetic consequences of introgression to determine how the genomic architecture of hybrids affects allelic inheritance, and thus their subsequent evolution. In Chapter 3, we generated a genetic linkage map for rainbow-Yellowstone cutthroat trout hybrids to evaluate genome process that may influence introgression genome evolution in hybrid populations. Our results suggest that few genomic incompatibilities exist between rainbow and cutthroat trout, allowing their to genomes introgress freely, with the exception that differences in chromosome arrangement between the species may act as barriers to introgression and enable large portions of non-recombined chromosomes to persist within admixed populations. In Chapter 4, we aimed to determine the effect of incomplete re-diploidization on transmission genetics in hybrids, compared to pure species. We used the parental gametic phase from existing genetic linkage maps to identify the homeologs that recombine, to characterize this recombination, and to verify meiotic models of residual tetrasomic inheritance in autotetraploids. Recombination between homeologs occurred frequently in hybrids and results in the non-random segregation of alleles across extended chromosomal regions as well as extensive double-reduction in hybrid parental gametes. Taken together, the results from Chapters 3 and 4 suggested that chromosome rearrangements and recombination of homeologs could influence genome evolution in admixed populations. The research presented in this dissertation indicated that the evolutionary fate of hybrid genomes is unpredictable. Some of our findings suggest that introgressions proceeds in a predictable fashion in admixed populations; rainbow and cutthroat genomes freely introgress, with the exception that chromosome rearrangements may suppress recombination across large chromosomal regions. However, homeologous recombination during meiosis in hybrids results in unpredictable segregation of chromosomes, and the segregation of these chromosomes may depend on the hybrid generation of each parent within an admixed population. Furthermore, phenotype and gene expression are quantitative traits, and expression of these traits may depend on hybrid genotypes across transcriptional networks that are controlled by genes distributed over the entire genome. Consequently, hybridization may alter transcriptional regulation of genes, resulting in unpredictable gene expression patterns, which, in turn, contribute to the high phenotypic variation in hybrids.
Book Synopsis The Hybrid Dilemma by : Andrew S. Harwood
Download or read book The Hybrid Dilemma written by Andrew S. Harwood and published by . This book was released on 2010 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Dual Challenges of Generality and Specificity When Developing Environmental DNA Markers for Species and Subspecies of Oncorhynchus by : Taylor M. Wilcox
Download or read book The Dual Challenges of Generality and Specificity When Developing Environmental DNA Markers for Species and Subspecies of Oncorhynchus written by Taylor M. Wilcox and published by . This book was released on 2015 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental DNA (eDNA) sampling is a powerful tool for detecting invasive and native aquatic species. Often, species of conservation interest co-occur with other, closely related taxa. Here, we developed qPCR (quantitative PCR) markers which distinguish westslope cutthroat trout (Oncorhynchus clarkii lewsi), Yellowstone cutthroat trout (O. clarkii bouvieri), and rainbow trout (O. mykiss), which are of conservation interest both as native species and as invasive species across each other?s native ranges. We found that local polymorphisms within westslope cutthroat trout and rainbow trout posed a challenge to designing assays that are generally applicable across the range of these widely-distributed species. Further, poorly-resolved taxonomies of Yellowstone cutthroat trout and Bonneville cutthroat trout (O. c. utah) prevented design of an assay that distinguishes these recognized taxa. The issues of intraspecific polymorphism and unresolved taxonomy for eDNA assay design addressed in this study are likely to be general problems for closely-related taxa. Prior to field application, we recommend that future studies sample populations and test assays more broadly than has been typical of published eDNA assays to date.
Book Synopsis Genomic and Fitness Consequences of Hybridization Between Cutthroat and Rainbow Trout by : Daniel P. Drinan
Download or read book Genomic and Fitness Consequences of Hybridization Between Cutthroat and Rainbow Trout written by Daniel P. Drinan and published by . This book was released on 2015 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybridization is an important and common evolutionary process that can contribute to diversification, adaptation, and speciation. When species hybridize, divergent genomes are combined through recombination and may result in phenotypic changes. Such phenotypic changes may be the result of differences in chromosomal structure or adaptive divergence between the parental species and may ultimately affect fitness. Understanding how phenotypes change following hybridization, as well as the genetic mechanisms responsible for changes is critical for understanding divergent selection, speciation, and identifying populations that may be at risk from hybridization. Here, the effect of hybridization between cutthroat (Oncorhynchus clarkii) and rainbow trout (O. mykiss) on fitness was investigated using three techniques. In the first chapter, fitness influencing traits were compared among individuals at various hybridization levels. In the second chapter, genomic changes that could affect fitness were identified in the hybrid relative to rainbow trout. And, in the third chapter, correlations between reproductive success and hybridization were investigated in a wild population, as well as the genomic and ecological mechanisms responsible for those changes. The first chapter of this dissertation aimed to identify how traits potentially involved in fitness (embryonic survival, ova size, ova energy concentration, sperm motility, burst swimming performance, juvenile survival, and juvenile growth) changed with hybridization between cutthroat and rainbow trout and whether those changes could explain previously observed reductions in reproductive success of individuals with increased rainbow trout ancestry. Using progeny from wild caught fish, differences in phenotypes based on hybridization were observed for embryonic survival, ova energy concentration, juvenile weight, and burst swimming based on ancestry. However, the correlations differed from previously observed patterns of reproductive success and likely do not explain declines in reproductive success associated with hybridization. The second chapter of this dissertation aimed to identify how hybridization affects the genome by identifying genomic regions with changes in recombination rates in the hybrid relative to rainbow trout as well as genomic areas with excess species-specific ancestry in the hybrid. Previous studies of hybridization have observed recombination suppression in genomic regions where structural differences, such as inversions or karyotype differences, exist between parental species. Such regions may retain groups of adaptive alleles. Additionally, adaptive divergence between the parental species may result in alleles that are preferentially selected in the hybrid progeny. Identification of regions with suppressed recombination or excess species-specific ancestry would provide insight into markers that may be important to fitness and that have differentially evolved in each of the parental species. In total, eight and seven chromosomes were identified to have changes in recombination rates in the hybrid female and male relative to O. mykiss. Recombination was suppressed in the hybrids on two chromosomes with known structural differences between the parental species. In addition, changes in recombination rates were observed on five chromosomes with high proportions of duplicated markers and may be due to increased homeologous chromosome pairing. Recombination patterns were similar between the sexes which suggests that hybridization affects recombination in the same way in females and males. Regions of excess species-specific ancestry covered 11 and 10% of the mapped genome in the female and male and regions of excess were evenly split between cutthroat trout and O. mykiss. Genetic drift may be responsible for much of the observed patterns of excess species-specific ancestry, but selection may also play a role. The aim of the third chapter of this dissertation was to identify the fitness consequences of hybridization, mechanisms responsible for the retention of hybridization, and genomic regions correlated with changes in reproductive success in a wild population of westslope cutthroat trout hybridized with non-native rainbow trout. Adult samples from a previous study, collected over a five year period, were sequenced at 3027 loci. Increased admixture from non-native rainbow trout had a strong, negative effect on reproductive success. A decline of 53% was observed for individuals with an increased genetic contribution of 0.20 from rainbow trout. Despite apparent strong selection against rainbow trout ancestry, hybridization appears to be maintained largely by the invasion of rainbow trout from outside populations as well as the relatively high fitness of few hybrid individuals. Ten loci correlated with reproductive success were identified in females. Seven of the ten loci were linked to chromosomes and three were positioned on chromosomes. Loci linked to reproductive success were identified on chromosomes with excess species-specific ancestry in hybrid progeny (RYHyb14 and RYHyb18) as well as chromosomes with a high proportion of duplicated markers (RYHyb02) and known Robertsonian polymorphism (RYHyb20). The research presented in this dissertation will elucidate our understanding of the phenotypic and genetic changes correlated with hybridization between rainbow and cutthroat trout as well as identify genetic and ecological mechanisms that may be responsible for those changes. In addition, results from this study provide insight into differences in adaptive divergence and markers that may be involved in the early stages of speciation in the wild. Results could be used by managers to identify populations that are at risk from hybridization.
Book Synopsis A Suite of Twelve Single Nucleotide Polymorphism Markers for Detecting Introgression Between Cutthroat and Rainbow Trout by : Andrew S. Harwood
Download or read book A Suite of Twelve Single Nucleotide Polymorphism Markers for Detecting Introgression Between Cutthroat and Rainbow Trout written by Andrew S. Harwood and published by . This book was released on 2011 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: A suite of 12 subspecies and species-specific single nucleotide polymorphism (species-specific SNP) markers was developed to distinguish rainbow trout (RT) Oncorhynchus mykiss from the four major subspecies of cutthroat trout: westslope cutthroat trout (WCT) Oncorhynchus clarki lewisi, Yellowstone cutthroat trout (YCT) Oncorhynchus clarki bouvieri, coastal cutthroat trout (CCT) Oncorhynchus clarki clarki, Lahontan cutthroat trout (LCT) Oncorhynchus clarki henshawi, and their hybrids. Several of the markers were linked to help strengthen hybrid determinations, and sex-specific species-specific SNP assays were also developed.
Book Synopsis Chromosome Rearrangements, Recombination Suppression, and Limited Segregation Distortion in Hybrids Between Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) and Rainbow Trout (O. Mykiss) by : Carl O. Ostberg
Download or read book Chromosome Rearrangements, Recombination Suppression, and Limited Segregation Distortion in Hybrids Between Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) and Rainbow Trout (O. Mykiss) written by Carl O. Ostberg and published by . This book was released on 2013 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Background Introgressive hybridization is an important evolutionary process that can lead to the creation of novel genome structures and thus potentially new genetic variation for selection to act upon. On the other hand, hybridization with introduced species can threaten native species, such as cutthroat trout (Oncorhynchus clarkii) following the introduction of rainbow trout (O. mykiss). Neither the evolutionary consequences nor conservation implications of rainbow trout introgression in cutthroat trout is well understood. Therefore, we generated a genetic linkage map for rainbow-Yellowstone cutthroat trout (O. clarkii bouvieri) hybrids to evaluate genome processes that may help explain how introgression affects hybrid genome evolution. Results The hybrid map closely aligned with the rainbow trout map (a cutthroat trout map does not exist), sharing all but one linkage group. This linkage group (RYHyb20) represented a fusion between an acrocentric (Omy28) and a metacentric chromosome (Omy20) in rainbow trout. Additional mapping in Yellowstone cutthroat trout indicated the two rainbow trout homologues were fused in the Yellowstone genome. Variation in the number of hybrid linkage groups (28 or 29) likely depended on a Robertsonian rearrangement polymorphism within the rainbow trout stock. Comparison between the female-merged F1 map and a female consensus rainbow trout map revealed that introgression suppressed recombination across large genomic regions in 5 hybrid linkage groups. Two of these linkage groups (RYHyb20 and RYHyb25_29) contained confirmed chromosome rearrangements between rainbow and Yellowstone cutthroat trout indicating that rearrangements may suppress recombination. The frequency of allelic and genotypic segregation distortion varied among parents and families, suggesting few incompatibilities exist between rainbow and Yellowstone cutthroat trout genomes.
Book Synopsis Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications by : Matthew R. Campbell
Download or read book Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications written by Matthew R. Campbell and published by . This book was released on 2002 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the mid-1920s, the Idaho Department of Fish and Game has cultured Yellowstone cutthroat trout Oncorhynchus clarki bouvieri at Henrys Lake to offset declines in natural production and for use in stocking programs throughout Idaho. Since the mid-1970s, they have also produced F1 hybrids: female Yellowstone cutthroat trout * male rainbow trout O. mykiss. The ability of fishery managers, when selecting broodstock, to visually distinguish returning cutthroat trout from F1 hybrids is, therefore, crucial to avoid accidental introduction of rainbow trout genes into the hatchery-supplemented cutthroat trout population. To evaluate this ability, fish identified by staff as putative cutthroat trout or hybrids (an array of phenotypic characters are used), were sampled during two spawning seasons. Phenotypically identified fish were genetically tested using species-specific restriction fragment length polymorphisms (RFLPs) of nuclear and mitochondrial DNA gene loci and diagnostic allozyme loci. Current levels of rainbow trout introgression in the cutthroat trout population at Henrys Lake were also investigated by analyzing samples collected from the lake and several of its tributaries. Results indicated that staff's phenotypic identifications were highly accurate in distinguishing cutthroat trout from F1 hybrids when selecting broodstock (no F1 hybrids were detected among 80 samples identified as pure). However, backcrosses of F1 hybrids were identified in random collections of adults from the lake as well as fry from Henrys Lake tributaries, indicating introgression. Present levels of rainbow trout introgression are most likely the product of past rainbow trout introductions and limited, intermittent spawning of hatchery-produced F1 hybrids with wild Yellowstone cutthroat, rather than the accidental crossing of F1 hybrids with cutthroat trout at the hatchery. Current levels of introgression are inadvertently maintained by (1) the inability of managers to phenotypically identify and exclude as broodstock individuals with low levels of rainbow trout introgression and (2) the limited, intermittent reproductive success of straying, hatchery-produced F1 hybrids.--Abstract.
Book Synopsis Impact of Triploid Rainbow Trout and Naturalized Rainbow Trout (Oncorhynchus Mykiss) on Recovery of Lahontan Cutthroat Trout (Oncorhynchus Clarkii Henshawi) in the Truckee River Watershed by : Veronica Kirchoff
Download or read book Impact of Triploid Rainbow Trout and Naturalized Rainbow Trout (Oncorhynchus Mykiss) on Recovery of Lahontan Cutthroat Trout (Oncorhynchus Clarkii Henshawi) in the Truckee River Watershed written by Veronica Kirchoff and published by . This book was released on 2016 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Historically the Lahontan cutthroat trout (Oncorhynchus clarkii henshawi, LCT) occurred throughout the Truckee River basin, supporting important commercial fisheries and was extirpated in the 1940s due to water diversions, predation, competition and hybridization with non-native trout. To provide angling opportunities, Rainbow trout (Oncorhynchus mykiss, RBT) has been planted, and there is a robust naturalized population throughout the Truckee River. Recovery efforts are underway to reintroduce the threatened LCT back into their native habitat in the Truckee; however, planting LCT sympatric with naturalized RBT can support hybridization between the species and hamper LCT recovery. Since 2004, in an effort to limit hybridization, 90% of the RBT stocked are non-reproductive triploid RBT. Over 3,400 trout samples were collected in the Truckee River and its tributaries from 2007-2010. These trout were identified as pure LCT, pure RBT, LCT/RBT hybrids or triploid RBT using bi-parentally inherited markers that differentiate between RBT and LCT and microsatellite markers that revealed triploidy in a proportion of the RBT. A mitochondrial marker was sequenced in hybrids to determine the maternal contribution to hybridization and to look at spawning success. The highest level of hybridization was found in 2008 from samples in the river tributaries. This correlates to the time period when fry stocked in 2005 and 2006 would reach sexual maturity. Backcrossing of hybrids with RBT was detected, and a low level of introgression indicates that hybridization has been occurring in the river for multiple generations. Mitochondrial sequences show that LCT is successfully competing for spawning gravels; however continued stocking of LCT without the removal of the naturalized RBT will likely lead to a hybrid swarm. Triploidy was successfully identified in the hatchery supplied known triploids; despite high levels of stocking of trpRBT, less than 10% of the RBT sampled in the Truckee River were identified as triploid. The diploid RBT samples represent the naturalized RBT population in the river. The genetic population structure of the naturalized RBT was investigated using 11 microsatellite loci to look for potential RBT eradication units allowing for LCT reintroduction. Barriers along the Truckee River contribute to developing population structure, but these barriers are transient, and structure varies year to year. No clear eradication units or regions of the river to potentially isolate a translocated LCT population from RBT encroachment were identified. Six of the 11 microsatellites cross amplified and showed variation in LCT. Comparison of the LCT and HYB sampled in the Truckee River to the LCT strains stocked indicates that the Pilot Peak Strain of LCT has a higher survivorship in the Truckee River compared to the contemporary Pyramid Lake or Independence Lake strains. Reintroduction of LCT into the Truckee River is possible, but would require the eradication of the reproductive RBT and extensive monitoring to detect hybridization.
Book Synopsis Linkage Studies in Rainbow Trout (Oncorhynchus Mykiss) by : Maria Fernanda Rodriguez
Download or read book Linkage Studies in Rainbow Trout (Oncorhynchus Mykiss) written by Maria Fernanda Rodriguez and published by . This book was released on 2003 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout Alters the Expression of Muscle Growth-Related Genes and Their Relationships with Growth Patterns by : Carl O. Ostberg
Download or read book Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout Alters the Expression of Muscle Growth-Related Genes and Their Relationships with Growth Patterns written by Carl O. Ostberg and published by . This book was released on 2015 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybridization creates novel gene combinations that may generate important evolutionary novelty, but may also reduce existing adaptation by interrupting inherent biological processes, such as genotype-environment interactions. Hybridization often causes substantial change in patterns of gene expression, which, in turn, may cause phenotypic change. Rainbow trout (Oncorhynchus mykiss) and cutthroat trout (O. clarkii) produce viable hybrids in the wild, and introgressive hybridization with introduced rainbow trout is a major conservation concern for native cutthroat trout. The two species differ in body shape, which is likely an evolutionary adaptation to their native environments, and their hybrids tend to show intermediate morphology. The characterization of gene expression patterns may provide insights on the genetic basis of hybrid and parental morphologies, as well as on the ecological performance of hybrids in the wild. Here, we evaluated the expression of eight growth-related genes (MSTN-1a, MSTN-1b, MyoD1a, MyoD1b, MRF-4, IGF-1, IGF-2, and CAST-L) and the relationship of these genes with growth traits (length, weight, and condition factor) in six line crosses: both parental species, both reciprocal F1 hybrids, and both first-generation backcrosses (F1 x rainbow trout and F1 x cutthroat trout). Four of these genes were differentially expressed among rainbow, cutthroat, and their hybrids. Transcript abundance was significantly correlated with growth traits across the parent species, but not across hybrids. Our findings suggest that rainbow and cutthroat trout exhibit differences in muscle growth regulation, that transcriptional networks may be modified by hybridization, and that hybridization disrupts intrinsic relationships between gene expression and growth patterns that may be functionally important for phenotypic.
Book Synopsis Preservation of eggs and genetic sex discrimination in rainbow trout (Oncorhynchus mykiss) by : Marina Komrakova
Download or read book Preservation of eggs and genetic sex discrimination in rainbow trout (Oncorhynchus mykiss) written by Marina Komrakova and published by Cuvillier Verlag. This book was released on 2006 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Diadromy in Fishes by : Robert Montgomery McDowall
Download or read book Diadromy in Fishes written by Robert Montgomery McDowall and published by Timber Press (OR). This book was released on 1988 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the fish which exhibit diadromy, their life history strategies and the implications for fisheries. The book should therefore represent an important volume for workers in fish biology, animal physiology and behaviour, and fisheries.
Book Synopsis Rainbow Trout (Oncorhynchus Mykiss) Invasion and the Spread of Hybridization with Native Westslope Cutthroat Trout (Oncorhynchus Clarkii Lewisi) by : Matthew C. Boyer
Download or read book Rainbow Trout (Oncorhynchus Mykiss) Invasion and the Spread of Hybridization with Native Westslope Cutthroat Trout (Oncorhynchus Clarkii Lewisi) written by Matthew C. Boyer and published by . This book was released on 2008 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: We analyzed 13 microsatellite loci to estimate gene flow among westslope cutthroat trout, Oncorhynchus clarkii lewisi, populations and determine the invasion pattern of hybrids between native O. c. lewisi and introduced rainbow trout, Oncorhynchus mykiss, in streams of the upper Flathead River system, Montana (USA) and British Columbia (Canada). Fourteen of 31 sites lacked evidence of O. mykiss introgression, and gene flow among these nonhybridized O. c. lewisi populations was low, as indicated by significant allele frequency divergence among populations (?ST = 0.076, ?ST = 0.094, P
Book Synopsis Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout in the Upper Snake River Basin, Wyoming by : Ryan P. Kovach
Download or read book Hybridization Between Yellowstone Cutthroat Trout and Rainbow Trout in the Upper Snake River Basin, Wyoming written by Ryan P. Kovach and published by . This book was released on 2011 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Human-induced hybridization between fish populations and species is a major threat to aquatic biodiversity worldwide and is particularly relevant to management of the subspecies of cutthroat trout Oncorhynchus clarkii. The upper Snake River basin in Wyoming contains one of the largest remaining populations of Yellowstone cutthroat trout O. clarkii bouvieri, a subspecies of special concern throughout its range; however, little is known about levels of hybridization between Yellowstone cutthroat trout and exotic rainbow trout O. mykiss or about the overall genetic population structure for this river basin. There is concern that the Gros Ventre River is a source of hybridization for the Snake River basin. We sampled across the upper Snake River basin to estimate levels of hybridization and population structure and to describe hybrid zone structure and spatial patterns of hybridization throughout the basin. We used this information to help resolve whether the Gros Ventre River was acting as a potential source of hybridization for the upper Snake River basin. We found that Yellowstone cutthroat trout genotypes dominated the river system, but hybridization was detected at low levels in all populations. The Gros Ventre River contained the highest levels of hybridization (population and individual) and displayed evidence of ongoing hybridization between parental genotypes. Levels of hybridization decreased as a function of distance from the Gros Ventre River, suggesting that this population is acting as a source of rainbow trout genes. These patterns were evident despite the fact that levels of genetic connectivity appeared to be higher than those observed in other cutthroat trout populations (global genetic differentiation index F ST = 0.04), and we did not find evidence for genetic isolation by distance. Management actions aimed at reducing the presence of highly hybridized cutthroat trout or rainbow trout individuals in the Gros Ventre River will help to maintain the upper Snake River basin as an important conservation area.
Book Synopsis Molecular Genetics in Fisheries by : Gary R. Carvalho
Download or read book Molecular Genetics in Fisheries written by Gary R. Carvalho and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: The basic principle of all molecular genetic methods is to employ inherited, discrete and stable markers to identify genotypes that characterize individuals, populations or species. Such genetic data can provide information ori the levels and distribution of genetic variability in relation to mating patterns, life history, population size, migration and environment. Although molecular tools have long been employed to address various questions in fisheries biology and management, their contributions to the field are sometimes unclear, and often controversial. Much of the initial impetus for the deployment of molecular markers arose from the desire to assess fish stock structure based on various interpretations of the stock concept. Although such studies have met with varying success, they continue to provide an impetus for the development of increasingly sensitive population discriminators, yielding information that can be valuable for both sustainable exploitation and the conservation of fish populations. In the last major synthesis of the subject, Ryman and Utter (1987) summarized progress and applications, though this was prior to the wide-scale adoption of DNA methodology. New sources of genetic markers and protocols are now available, in particular those that exploit the widely distributed and highly variable repeat sequences of DNA, and the amplification technique of the polymerase chain reaction.
