ix, 62 leaves : ill. ; 29 cm Notes Typescript Thesis (M.S.)--University of Oregon, 1987 Includes vita and abstract Bibliography: leaves 59-62 Another copy on microfilm is located in Archives

This thesis examines the ontogeny of plasma sodium regulation (an indicator of osmoregulatory ability), current or rheotactic response (an indicator of emigration timing) and salinity preference in juvenile coho salmon (Oncorhynchus kisutch). The purpose of the study was to determine if there are inherited differences in the development of these traits between coastal and interior British Columbia populations of coho. An interior (Cold water River) and a coastal (Rosewall Creek-Big Qualicum River) population were monitored for the above traits throughout the year. Both wild and laboratory groups were included in the study. The laboratory raised populations were divided into two incubation treatment groups: one incubated under a coastal temperature regime, and the other incubated under an interior temperature regime. There were no differences in the development of sodium regulatory ability between wild populations when the data were sorted by coho weight. Coastal coho, however, physiologically smolted after one year in the natal streams, while interior coho smolted after at least two years of freshwater growth. No obvious differences were noted between wild resident populations in the timing of downstream movement or the shift in salinity preference from hypotonic to isotonic and hypertonic salinities. Both of these behavioural responses typically occurred in the spring (April-May) of each year. Fyke net catches, however, sugqested that, in addition to the spring emigrations observed in both populations, a portion of the interior population migrated in the fall (November). No differences in the development of sodium regulatory ability were observed either within or between laboratory raised populations. Ion regulatory ability increased to a plateau in the fall and winter following emergence, and increased to smolting levels during the following spring (April-May). There were differences between coastal and interior populations in the pattern of development of both nocturnal current responses and the preference for isotonic or hypertonic salinities. Interior laboratory raised coho developed negative nocturnal rheotaxis and a preference for isotonic salinities about three months earlier (November) than laboratory raised coastal coho (late February-March). Within populations, no differences were observed in the ontogeny of these traits in the groups reared under different temperature regimes. Because these interpopulation ontogenetic behavioural differences persisted in fish reared under identical laboratory conditions, they probably have some genetic basis. Such an innate component in behaviour implies an adaptive role and in juvenile coho these behavioural traits may allow populations to use a variety of habitats at different distances from the sea, even though a major physiological schedule (in this case the development of ion regulatory capabilities) appears to be fixed within the species. Perhaps variations in migratory timing and salinity preference in juvenile coho evolved to assure survival in a relatively unstable and often severe environment by optimizing habitat use within the constraints of an overriding physiological schedule. / Science, Faculty of / Zoology, Department of / Graduate

Ng Ho Yuen Andus. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 105-131). / Abstracts in English and Chinese. / Chapter I --- Title page --- p.i / Chapter II --- Thesis committee --- p.ii / Chapter III --- Acknowledgement --- p.iii / Chapter IV --- Abstract --- p.v / Chapter V --- Abstract (Chinese version) --- p.vii / Chapter V --- Table of contents --- p.ix / Chapter VI --- List of abbreviations --- p.xv / Chapter VII --- List of figures --- p.xviii / General introduction --- p.1 / Chapter Chapter 1: --- Literature review --- p.5 / Chapter 1.1. --- Heat shock proteins (HSPs) --- p.6 / Chapter 1.1.1. --- Introduction --- p.6 / Chapter 1.1.2. --- The various heat shock proteins --- p.8 / Chapter 1.1.2.1. --- HSP100s --- p.8 / Chapter 1.1.2.2. --- HSP90s --- p.9 / Chapter 1.1.2.3. --- HSP70s --- p.12 / Chapter 1.1.2.3.1. --- ATPase reaction cycle of HSP70 and protein folding --- p.13 / Chapter 1.1.2.3.2. --- Protein translocation --- p.14 / Chapter 1.1.2.3.3. --- Selective lysosomal proteolysis --- p.16 / Chapter 1.1.2.4. --- HSP60s --- p.16 / Chapter 1.1.2.5. --- Small HSPs --- p.17 / Chapter 1.1.2.6. --- Ubiquitin --- p.19 / Chapter 1.1.3. --- HSP studies in fish --- p.21 / Chapter 1.1.3.1. --- In vivo works --- p.21 / Chapter 1.1.3.2. --- In vitro works --- p.23 / Chapter 1.2. --- Growth hormone / prolactin family in teleostean fishes --- p.26 / Chapter 1.2.1. --- Introduction --- p.26 / Chapter 1.2.2. --- Growth hormone (GH; somatotropin) --- p.29 / Chapter 1.2.2.1. --- Structure --- p.29 / Chapter 1.2.2.2. --- Actions --- p.29 / Chapter 1.2.2.3. --- Insulin-like Growth Factors (IGFs; somatomedins) --- p.31 / Chapter 1.2.3. --- Prolactin (PRL) --- p.34 / Chapter 1.2.3.1. --- Structure --- p.34 / Chapter 1.2.3.2. --- Actions --- p.35 / Chapter 1.2.4. --- Somatolactin (SL) --- p.37 / Chapter 1.2.4.1. --- Structure --- p.37 / Chapter 1.2.4.2. --- Actions --- p.38 / Chapter 1.2.5. --- Growth hormone receptor (GH-R) and prolactin receptor (PRL-R) --- p.39 / Chapter 1.3. --- Cortisol in teleostean fishes --- p.41 / Chapter 1.4. --- Salinity adaptation in teleosts --- p.44 / Chapter Chapter 2: --- Effect of in vitro thermal shock on HSP70 expression in whole blood of Sparus sarba --- p.46 / Chapter 2.1. --- Introduction --- p.47 / Chapter 2.2. --- Materials and methods --- p.49 / Chapter 2.2.1. --- Overall experimental design --- p.49 / Chapter 2.2.2. --- Experimental fish --- p.49 / Chapter 2.2.3. --- Blood sampling and preparation --- p.49 / Chapter 2.2.4. --- Thermal stress regimes --- p.50 / Chapter 2.2.5. --- Protein extraction --- p.51 / Chapter 2.2.6. --- Protein quantification --- p.51 / Chapter 2.2.7. --- Indirect enzyme-linked immunosorbent assay (ELISA) --- p.52 / Chapter 2.2.8. --- Protein gel electrophoresis and immunoblotting (Western blotting) --- p.54 / Chapter 2.2.9. --- Statistical analysis --- p.55 / Chapter 2.3. --- Results --- p.56 / Chapter 2.3.1. --- Validation of indirect ELISA --- p.56 / Chapter 2.3.2. --- Effect of in vitro thermal shock on HSP70 expression in whole blood of Sparus sarba --- p.56 / Chapter 2.4. --- Discussion --- p.60 / Chapter 2.5. --- Conclusion --- p.64 / Chapter Chapter 3: --- Effects of hormones on HSP70 expression in whole blood of Sparus sarba in vitro --- p.65 / Chapter 3.1. --- Introduction --- p.66 / Chapter 3.2. --- Materials and methods --- p.68 / Chapter 3.2.1. --- Overall experimental design and experimental fish --- p.68 / Chapter 3.2.2. --- Hormone treatments --- p.59 / Chapter 3.2.3. --- "Protein extraction and quantification, indirect ELISA，gel electrophoresis, and immunoblotting (Western blotting)" --- p.70 / Chapter 3.2.4. --- Statistical analysis --- p.70 / Chapter 3.3. --- Results --- p.71 / Chapter 3.3.1. --- Effect of Cortisol on HSP70 levels in whole Blood --- p.71 / Chapter 3.3.2. --- Effect of recombinant bream growth hormone on HSP70 levels in whole blood --- p.71 / Chapter 3.3.3. --- Effect of recombinant bream insulin-like growth factor-I on HSP70 levels in whole blood --- p.71 / Chapter 3.3.4. --- Effect of ovine prolactin on HSP70 levels in whole blood --- p.72 / Chapter 3.4. --- Discussion --- p.81 / Chapter 3.4.1. --- Effect of Cortisol on HSP70 levels in whole Blood --- p.81 / Chapter 3.4.2. --- Effect of recombinant bream growth hormone on HSP70 levels in whole blood --- p.83 / Chapter 3.4.3. --- Effect of recombinant bream insulin-like growth factor-I on HSP70 levels in whole blood --- p.85 / Chapter 3.4.4. --- Effect of ovine prolactin on HSP70 levels in whole blood --- p.86 / Chapter 3.5. --- Conclusion --- p.88 / Chapter Chapter 4: --- Effect on HSP70 expression in whole blood of Sparus sarba acclimated to various salinities --- p.89 / Chapter 4.1. --- Introduction --- p.90 / Chapter 4.2. --- Materials and methods --- p.92 / Chapter 4.2.1. --- Overall experimental design and experimental fish --- p.92 / Chapter 4.2.2. --- "Protein extraction and quantification, indirect ELISA, gel electrophoresis, and immunoblotting (Western blotting)" --- p.92 / Chapter 4.2.3. --- Statistical analysis --- p.93 / Chapter 4.3. --- Results --- p.94 / Chapter 4.4. --- Discussion --- p.97 / Chapter 4.5. --- Conclusion --- p.100 / Chapter Chapter 5: --- General discussion and conclusion --- p.101 / References --- p.105

This study examines the effects of a low oxygen environment, in concert with fluctuating temperature and salinity conditions, on the nearshore depth distributions (0-1 m) and flood tide movements of juvenile chinook (Oncorhynchus tshawytscha) and chum (O. keta) salmon. Comparisons are made between an unpolluted and a sewage polluted estuarine intertidal flat in the Fraser River estuary, British Columbia, the polluted area being characterized by the regular occurrence of low dissolved oxygen levels. Results are based on 380 beach seine samples taken between April and June of 1984. In general, chum and chinook salmon of increasing length were captured in increasing depths, though this pattern was modified by seasonal changes in water temperature. Low dissolved oxygen conditions in deeper waters may have been responsible for the presence of larger, and often sluggishly swimming fish in higher oxygenated surface water layers or in shallow waters near the shore. In both areas, the risk of aerial predation was high. On a flood tide, the likelihood of capturing a chinook salmon was reduced as temperatures increased and oxygen levels decreased. A combination of avoidance behaviour and a regularity in the movement patterns of chinook onto the study area in the later stages of the flood tide may account for their rare occurrence in low oxygen concentrations (<6 mg/1) and high temperatures (>20 °C). Fish mortalities were most likely to occur on the ebb tide when fish were forced into waters of low oxygen content by the drainage patterns characteristic of the polluted study area. Though wide ranges in salinity were recorded on both tidal flats, this factor was not strongly correlated to Chinook distributions. However, significantly higher salinity levels in the unpolluted area may account for the greater numbers of chum salmon captured there. An understanding of the influence of estuarine water quality conditions on the distribution of juvenile salmonids may assist in the identification of significant sources of mortality in their early marine life. This knowledge is particularly important in the evaluation of water quality changes as caused by human activity. / Science, Faculty of / Zoology, Department of / Graduate