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The effects of handling and transportation on Coho salmon fry incubated in hatchboxesGestring, Kelly Brad January 1989 (has links)
Typescript.
Includes vita and abstract.
Bibliography: Includes bibliographical references (leaves 53-56).
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Características microbiológicas de salmão (Salmo salar) comercializado em algumas cidades da região nordeste do estado de São PauloNespolo, Natália Maramarque [UNESP] 03 July 2009 (has links) (PDF)
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nespolo_nm_me_jabo.pdf: 317079 bytes, checksum: b5a59555adeaded005ddc00b0895ba68 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Tem sido evidente o aumento no consumo de pescado, especialmente do salmão (Salmo salar) sob a forma “in natura”, em pratos da cozinha oriental. Como conseqüência, tem havido maior preocupação quanto às suas características higiênico-sanitárias, tendo em vista a facilidade que microrganismos encontram para se desenvolverem em sua carne, o que pode expor os consumidores a agentes que causam desde uma simples gastrenterite até o óbito. Diante desta preocupação, desenvolveu-se este estudo com objetivos de avaliar características microbiológicas do salmão por meio da quantificação de microrganismos heterotróficos mesófilos, coliformes totais e termotolerantes, o perigo de veiculação de Vibrio parahaemolyticus, Staphylococcus aureus, Salmonella sp., Escherichia coli e Aeromonas sp. através da carne e contribuir com subsídios técnicos para criar uma legislação brasileira com padrões microbiológicos específicos para o pescado consumido cru. Foram colhidas 31 amostras de salmão, 16 refrigeradas e 15 congeladas, no comércio varejista de cidades da região nordeste do estado de São Paulo. Os resultados obtidos mostram populações de microrganismos heterotróficos mesófilos variando entre 1,0 x 10 e 3,9 x 106 UFC/g, coliformes totais e termotolerantes em, respectivamente, 32,24% e 19,33% das amostras e Aeromonas sp. em 35,48% das amostras com variação populacional de 2,0 x 102 a 8,0 x 103 UFC/g. Ainda houve a presença de Staphylococcus aureus em uma amostra e ausência de Vibrio parahaemolyticus, Salmonella sp. e Escherichia coli. Os resultados obtidos podem servir de parâmetro para a criação de um padrão microbiológico específico para o pescado consumido cru e servem também de alerta para os consumidores do produto tendo em vista a veiculação de microrganismos potencialmente patogênicos. / The increasing of seafood consumption has become evident especially in the use of salmon (Salmo salar) consumed raw in oriental dishes. Consequently, it has risen up the concern related to their hygienic-sanitary characteristics due to the facility that microorganisms multiply in the meat which can expose consumers to the causative agents of a mild gastroenteritis until the death. Regarding such informations, this study was aimed to evaluate microbiological characteristics of salmon by quantifying microrganisms heterotrophic mesophiles, total coliforms and thermotolerant. It was also evaluated the danger of transmission of Vibrio parahaemolyticus, Staphylococcus aureus, Salmonella sp., Escherichia coli and Aeromonas sp. on the fish muscle and contributed to technical informations to create a Brazilian regulations about specific microbiological standards for consumption of raw seafood. Thirty-one samples of salmon were collected, 16 chilled and 15 frozen, from the retail market in cities of the northeast region of São Paulo State. The results show populations of mesophilic heterotrophic microorganisms ranging from 1.0 x 10 and 3.9 x 106 CFU/g, in total and fecal coliforms, respectively, 32.24% and 19.33% of samples and Aeromonas sp. in 35.48% of samples ranging population of 2.0 x 102 to 8.0 x 103 CFU/g. Staphylococcus aureus was present in one sample and were not found Vibrio parahaemolyticus, Salmonella sp. and Escherichia coli. The results may serve as a parameter for the establishment of a microbiological standard for the consumption of raw seafood and also as a warning to consumers of the product for the presence of potentially pathogenic microorganisms.
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Influences of dietary polyunsaturated fatty acids on tissue fatty acid composition and eicosanoid production in Atlantic salmon (Salmo salar)Bell, John Gordon January 1996 (has links)
1. The literature has been reviewed with respect to the dietary intake and subsequent metabolism of polyunsaturated fatty acids (PUFA), of both the n-6 and n-3 series, in teleost fish. Particular emphasis has been made to the physiological roles of PUFA with respect to cell membrane function and eicosanoid production. 2. Atlantic salmon post-smolts were fed practical-type diets, based on fish meal, in three separate dietary experiments of 10-16 weeks duration. The first trial compared dietary lipid supplied either as fish oil (FO) or as sunflower oil (SO) with the diets having an n-3/n-6 PUFA ratio of 9.4 and 0.2 respectively. The second trial used diets formulated with blends of FO, SO, grape seed oil and safflower oil to provide linoleic acid at 10, 25 and 45% of total dietary fatty acids. The third trial was similar to the first but with an additional diet in which the lipid component was supplied by linseed oil (LO). All diets satisfied the nutritional requirements of salmonid fish for n-3 PUFA. There were no statistically significant differences in final weights between dietary treatments in the third trial. However, in the second trial fish fed the intermediate level of linoleic acid (25%) attained a significantly higher final weight compared to both other treatments while fish fed the highest level of linoleic acid (45%) had significantly lower final weights compared to both other treatments. In the first trial the effect of diet on growth (weight gain) could not be ascertained as the initial weights of the fish were significantly different. 3. A number of fish fed SO developed severe cardiac lesions which caused thinning of the ventricular wall and heart muscle necrosis. In addition the fish fed diets containing SO were susceptible to a transportation-induced shock syndrome that resulted in 30% mortality. 4. Incorporation of linoleic acid (18:2n-6) into membrane phospholipids increased in response to dietary intake with fish fed SO having increased levels of 18:2n-6 (up to 15-fold), 20:2n-6 (up to 12-fold), 20:3n-6 (up to 25-fold) and arachidonic acid (AA; 20:4n-6) (up to 3-fold), and decreased levels of eicosapentaenoic acid (EPA; 20:5n-3) (up to 3-fold). The ratio of n-3/n-6 PUFA was decreased (up to 4-fold) and the20:4n-6/20:5n-3 ratio increased (up to 9-fold) in membrane phospholipids from fish fed SO compared to those fed fish oil. While the tissue phospholipids from fish fed La had increased levels of 18:2n-6, 20:2n-6 and 20:3n-6, the levels of AA, 22:4n-6 and 22:5n-6 were similar to or significantly reduced compared to fish fed FO. Membrane phospholipids from fish fed LO also had increased 18:3n-3 and 20:4n-3 compared to both other treatments while in some tissues and phospholipid classes EPA was increased compared to fish fed FO. 5. These dietary induced changes in phospholipid eicosanoid precursor ratio were reflected in altered eicosanoid production. In gill cells, stimulated with the calcium ionophore A23187, 12-hydroxy-8, 10, 14, 17-eicosapentaenoic acid (12-HEPE) was the major 12-lipoxygenase product in fish fed Fa. In stimulated gill cells from fish fed SO and LO, 12-HEPE, 12-hydroxy-5, 8, 10, 14-eicosatetraenoic acid (12-HETE), 14- hydroxy-4, 7, 10, 13, 16, 19-docosahexaenoic acid (14-HDHE) and thromboxane B2 (TXB2) were all decreased compared to fish fed FO. However, the ratio of 12- HETE/12-HEPE was significantly elevated in stimulated gill cells from SO-fed fish compared to both other treatments. In stimulated blood leucocytes leukotriene B4 (LTB4)' 12-HETE and TXB2 were significantly increased while LTB5 and 12-HEPE were significantly decreased in fish fed SO compared to those fed FO. Blood leucocytes from fish fed LO produced less TXB2 compared to fish fed SO and prostaglandin E2 was reduced compared to both other treatments. In isolated cardiac myocytes stimulated with A23187, TXB2 production was increased in SO fed fish compared to those fed FO. 6. The activity of cardiac sarcoplasmic reticulum Ca2+-Mg2+ATPase was not affected by dietary treatment. 7. An established cell line derived from chum salmon heart (CHH-1) was utilised to study PUFA metabolism. The CHH-1 cells exhibited considerable A6 desaturase activity but showed no preference towards n-3 over n-6 PUFA. CHH-1 cells did exhibit significant A5 desaturase activity which showed a preference towards n-3 PUFA. No A4 desaturation activity was observed. Elongation of C20 PUFA was especially active in CHH-1 cells with C22 PUFA being specifically incorporated into phosphatidylethanolamine (PE) and phosphatidylserine (PS). CHH-1 cells supplemented with 20:3n-6 showed reduced growth rate, cell death and unusual pycnotic appearance, compared to those supplemented with other PUFA. 8. The lipid compositions of hearts and livers from wild and farmed parr and presmolts were analysed and compared. The fatty acid compositions of triacylglycerols (TAG) and phospholipids from both farmed parr and pre-smolts contained greater amounts of monoenoic fatty acids compared to their wild counterparts. TAG, phosphatidylcholine (PC) and PE from heart and liver of wild fish contained more 18:2n-6 and AA compared to farmed fish. Linolenic acid, EPA and 22:Sn-3 were increased in hearts and livers of wild fish compared to farmed. Docosahexaenoic acid (DHA; 22:6n-3) levels were higher in heart and liver of farmed fish, particularly in heart PC, PS and TAG. The n-3/n-6 PUFA ratio was generally lower in wild compared to farmed fish, largely due to higher n-6 PUFA, in particular AA, in wild fish. 9. The results are discussed with respect to the competitive interactions between PUFA of the n-6 and n-3 series which determine the fatty acid compositions of membrane phospholipids in salmon. The ratio of n-3/n-6 PUFA in membrane phospholipids, and in particular the ratio of AAIEPA, appears important in terms of membrane physiology and biochemistry, eicosanoid production and the development of cardiac histopathological lesions.
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Transposable elements in the salmonid genomeMinkley, David Richard 30 April 2018 (has links)
Salmonids are a diverse group of fishes whose common ancestor experienced an evolutionarily important whole genome duplication (WGD) event approximately 90 MYA. This event has shaped the evolutionary trajectory of salmonids, and may have contributed to a proliferation of the repeated DNA sequences known as transposable elements (TEs). In this work I characterized repeated DNA in five salmonid genomes. I found that over half of the DNA within each of these genomes was derived from repeats, a value which is amongst the highest of all vertebrates. I investigated repeats of the most abundant TE superfamily, Tc1-Mariner, and found that large proliferative bursts of this element occurred shortly after the WGD and continued during salmonid speciation, where they have produced dramatic differences in TE content among extant salmonid lineages. This work provides important resources for future studies of salmonids, and advances the understanding of two important evolutionary forces: TEs and WGDs. / Graduate / 2019-04-19
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Fish forensics: environmental DNA detection of juvenile coho salmon and resident salmonids in Pacific coastal streamsMacAdams, Jeffrey 02 May 2018 (has links)
Conventional fish monitoring requires considerable investments of equipment and labour, and often harmful and potentially fatal techniques. Emerging methods allow detection of aquatic animals by collecting water and extracting DNA that has been shed to the environment (eDNA). Present knowledge gaps in the field include minimum densities necessary for consistent detection, and persistence of eDNA after a target species has left a site.
I conducted three experiments at a salmon hatchery in British Columbia to address these knowledge gaps. Water samples were taken from flow-through tanks with juvenile Coho Salmon densities ranging from 38.0g/1000L to 0.6g/1000L. To simulate field surveys in recently abandoned habitats, I sampled water from tanks after removing fish, at flow-through volumes ranging from 20,000L to 1,000,000L. Post removal sampling occurred starting at one hour and ending after just over four days of flow-through time. Water samples from tanks containing one or more fish tested positive for Coho DNA at least 70% of the time, increasing at higher densities. Samples taken after removing the fish had detection probability of 75% at flow-through volume of 40,000L. Detection failed at flow-through volumes greater than 80,000L.
In stream samples, all sites with Coho or salmonid presence confirmed by conventional trapping also tested positive for target species’ eDNA. Two sites tested positive for Coho eDNA where conventional methods failed, indicating a possible higher sensitivity of eDNA sampling. I also mapped the distribution of juvenile Coho Salmon through multiple tributaries of a productive salmon system with conventional and eDNA detections.
This study improves on an emerging method with a new species by addressing existing uncertainties regarding eDNA detection threshold, and signal persistence through dilution in a simulated stream pool habitat. It also demonstrates that eDNA methods can be used to assess coastal streams for presence of juvenile and resident salmonid fishes. / Graduate
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Salmon cardiac peptide as a model for natriuretic peptide secretion:the role of mechanical load, temperature and endothelin-1Vierimaa, H. (Heidi) 19 September 2006 (has links)
Abstract
The natriuretic peptides are a family of hormones secreted by the heart. They play a fundamental role in salt and water balance and blood pressure regulation. Atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) are the known members of the mammalian natriuretic peptide family. A major stimulus for the secretion of cardiac natriuretic peptides is myocyte stretch. Therefore, the secretion of natriuretic peptides is increased in response to elevated blood volume. Natriuretic peptide production and release is also affected by several other factors, such as endothelin-1 (ET-1), acting in paracrine fashion.
The aim of this study was to elucidate factors regulating the novel cardiac peptide hormone, salmon cardiac peptide (sCP), belonging to the family of natriuretic peptides. The role of mechanical load, temperature and ET-1 in sCP secretion and production was studied using in vitro (isolated perfused ventricle preparation) and in vivo methods. Comparisons between the natriuretic peptide systems in fish and mammals were done to clarify functional evolution of this hormone family. Salmon (Salmo salar) was selected as a model, since it has an outstanding adaptability to wide variations in environmental salinity and has developed defence mechanisms against volume or salt load.
The results showed that salmon ventricle stores large amounts of the prohormone of sCP, whereas the secreted form is the mature 29-amino acid form. The N-terminal fragment of pro-sCP is co-secreted with sCP in equimolar amounts. sCP is released rapidly in response to appropriate stimulus, whereas induction of its gene expression is slower. Mechanical load is an important regulator of sCP secretion. Temperature also plays a major role in regulating sCP plasma concentration by affecting its elimination from circulation. Additionally, ET-1 is a potent secretagogue of the sCP system and an inotropic agent in salmon heart. Furthermore, the present results reveal remarkable synergism between the cardiac effects of ET-1 and β-adrenergic stimulation.
In conclusion, the sCP system in salmon ventricle largely resembles the ANP system in mammalian atrium, while also having specific characteristics, such as a regulated ventricular natriuretic peptide secretion pathway. Therefore, the sCP system offers a unique model for studying mechanisms of natriuretic peptide biology.
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1900 strike of Fraser River sockeye salmon fishermenRalston, Harry Keith January 1965 (has links)
This study sees the 1900 strike on the Fraser River as providing the setting in which trade unions began in the fisheries of British Columbia, and analyzes both the strike itself and its background from that point of view.
In the two decades to 1890, the Fraser River salmon canning industry grew relatively slowly, limited by the problems of developing techniques for processing, finding labor for packing, and accumulating capital from profits. In the 10 years to 1900, these difficulties had been mostly overcome, and fresh capital, attracted by sizeable profits, nearly tripled the number of canneries. This boom ended in a crisis of over-expansion, marked by strikes and company mergers.
One unforeseen effect of license limitation in the seasons I889-I89I was a change from paying fishermen a daily wage to paying them at so much per fish, and consequently the start of a series of disputes between canners and fishermen over fish prices. Though in general prices rose throughout the 1890*s, the individual fishermen failed to benefit, partly because of price cuts and limits on deliveries during periods of a heavy supply of fish, and partly because of the increasing number of fishermen licensed in each succeeding year.
In an attempt to increase their bargaining strength, white resident fishermen campaigned for changes in federal fishery regulations to restrict competition from Japanese and American fishermen, and to reduce the number of cannery licenses. The first fishermen's organization, formed in 1893 to further this end, did not survive its unrelated involvement in a strike that year against price cuts. The amendments to the fishery regulations in 1894 and, to an even greater degree, in 1898 reflected the success of this group in gaining their ends by political means. To try to redress the balance, the canners created in 1898 their own closely-knit organization, the British Columbia Salmon Packers’ Association.
The difficulties of the seasons of 1898 and 1899, basically caused by over-expansion, led the canners to tighten their organization further by creating in January, 1900, the Fraser River Canners’ Association, a cannery combine with power to set maximum fish prices and production quotas for each cannery, and to levy fines on violators of its decisions. About the same time, and partly in reaction to the canners' move, separate unions of fishermen were organized, first at New Westminster, then at Vancouver. The Vancouver union tried and failed to enroll Japanese fishermen who formed in June, 1900, the Japanese Fishermen's Benevolent Society.
The Canners’ Association refused to negotiate prices with fishermen's union representatives or to set a minimum price for sockeye. When the sockeye season opened July 1 the fishermen struck, demanding 25 cents a fish through the season. By July 10, the strike included all fishermen on the river—white, Japanese and Indian. After another week, the Canners' Association felt forced to negotiate and in a series of meetings the two sides came close to settlement. At this point, however, the canners broke off negotiations and made a separate agreement with the Japanese for 20 cents for the first 600 fish in a week and 15 cents thereafter. The canners then provoked an "incident" as an excuse for three friendly justices of the peace to call out the militia to Steveston.
In spite of the Japanese defection and the presence of the militia, the remaining strikers held out for another week. Mediation by E. P. Bremner, Dominion Labor Commissioner, and Francis Carter-Cotton, publisher of the Vancouver News-Advertiser, secured them a negotiated settlement which, though not including any union recognition, guaranteed 19 cents throughout the season.
This success led to the creation in January, 1901, of the Grand Lodge of British Columbia Fishermen's Unions, the first coast-wide fishermen's organization in British Columbia. The strike marked the beginning of continuous union activity in the industry and the start of a tradition of radical leadership that persists to the present day. / Arts, Faculty of / History, Department of / Graduate
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Optimal harvest policies in salmon gauntlet fisheries : terminal versus mixed stock fishery harvestLuedke, Wilfred Harold January 1990 (has links)
A case study of the chum salmon (Oncorhynchus keta) gauntlet fisheries in Southern British
Columbia is described. Acrimony between industry and government managers has been
commonplace in the management of this fishery. In an attempt to alleviate this acrimony, a
management system call the "clockwork" has been implemented, which provides all fishermen
an opportunity for greater understanding of the management rationale and greater input into
the decision-making process. The clockwork has been generally successful; the stocks are
rebuilding and the fishermen are involved in the management of the fishery.
However, two problems are identified in the clockwork. First, the success of the clockwork
in alleviating the aaimony associated with the chum fishery depends on the ability of
fishery managers to provide sound and scientifically defensible in-season stock assessments.
If the assessments have no better track record than the intuition of managers and fishermen
then the clockwork will not be successful.
Second, there is a nagging problem of allocation of harvests between the mixed stock
fishery in Johnstone Strait and the terminal fishery in the Fraser River. The main factor is the
difference in price behveen the two fisheries; the price in the terminal fishery is only about
one-third of the price paid in the mixed stock fishery, Dynamic programming techniques are
used to determine the optimal harvest strategies for this gauntlet fishery. Generally, the optimal
strategy is similar to a fixed escapement strategy when both stocks are equally abundant.
But when one stock is much more abundant the optimal strategy is to harvest harder in the
mixed stock fishery. With the current difference in value per fish between the two fisheries,
the optimal exploitation rates in the terminal area are zero, all the catch is taken in the mixed
stock fishery. The minimum price at which terminal fisheries provide long term economic
benefit is the threshold price. For the parameters used to describe the current fishery, the
threshold price is approximately 40% of the mixed stock fishery price. Furthermore, the
threshold price differs with stock recruitment parameters, especially stock productivity
and recruitment variability. Generally the more similar the stocks are, with respect to stock
and recruitment characteristics, the lower the threshold value for fishing in the terminal areas.
The results provide a basis for discussion of the utility of terminal fisheries, and by
adjusting the relative value of the terminal fishery in relation to the mixed stock fishery can
incorporate additional social and aesthetic values, as well as costs such as harvesting costs and
fisheries management costs. / Science, Faculty of / Zoology, Department of / Graduate
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Heritabilities and genetic correlations for weight, length and survivability in fresh water and salt water of SO and S1 coho salmon, (Oncorhynchus kisutch)Swift, Bruce D. January 1991 (has links)
Heritabilties and genetic correlations using Individual Animal Model, (IAM), analysis for weight, length and survivability were determined in both freshwater and saltwater rearing of s0 and si1 coho, (Oncorhynchus kisutch). The most important trait to salmon farmers is the saltwater market weight which was found to have heritability estimates of 0.21 and 0.45 for the s1 and s0 smolts. Estimates of heritability for survival were high, (0.29 and 0.21) for both s0 and s1 rearing strategies. Genetic correlations between freshwater and saltwater size were small, (0.33 to 0.59) indicating selection for market weight should be done during the saltwater market weight window. Significant differences were found for weight and length between strains during freshwater and saltwater rearing for both s0 and si1 coho.
The northern strains, (Kitimat, Bella Coola and Pallant Creek) were significantly larger in weight and length thanthe southern strains, (Big Qualicum and Robertson Creek). The Kitimat strain was larger in weight and length than the Bella Coola and Pallant Creek strains but lower than these two strains for percent survivability. When comparing fish from the Kitimat strain reared on both a s0 and s1 rearing strategy, it was found that the s1 fish were significantly larger than the s0 fish at the market weight window. / Land and Food Systems, Faculty of / Graduate
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Seasonal movements and foraging behaviour of resident killer whales (Orcinus orca) in relation to the inshore distribution of salmon (Oncarhynchus spp.) in British ColumbiaNichol, Linda M. January 1990 (has links)
Sightings and acoustic recordings from 1984 to 1989 of northern resident killer whales (Orcinus orca) from Johnstone Strait off north eastern Vancouver Island and from King Island on the central British Columbia coast were analysed to examine the hypothesis that northern resident whales move seasonally in their range to areas where salmon are available. Killer whales were most abundant in Johnstone Strait between July and October and infrequent during the remainder of the year. The increase in whale abundance during summer coincided with the migration of salmon (Oncorhynchus spp.) from offshore into Johnstone Strait. The occurrence near King Island in spring 1989 of the same resident whales that are seen in Johnstone Strait during summer, coincided with runs of sockeye and chinook salmon.
During July, August and September of 1984 through 1988, killer whale sightings were recorded virtually daily in the Johnstone Strait. Observations of killer whales in Johnstone Strait during the summer of 1988 showed that whales foraged along shore and in areas of strong current where salmon occur in high densities. Of the 16 killer whale pods in the northern resident community, however, less than half were present more than 15% of summer days (1984 to 1988). Regression results between numbers of whale days per week from each pod and numbers of salmon per week showed that the occurrence pods that were present on more than 15% of summer days in Johnstone Strait was positively and significantly associated with the abundance of sockeye and pink salmon (six pods). In addition to these, the occurrence of one pod that spent less than 15% of summer days in the Strait was positively and significantly associated with chum salmon.
Together these results support the hypothesis that northern resident killer whales select their habitat seasonally to feed on available salmon. The results also lead to the hypothesis that within the northern resident community each pod has a seasonal home ranges. / Land and Food Systems, Faculty of / Graduate
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