Once historically widespread throughout the Willamette and Umpqua River drainages, the Willamette Oregon chub is now restricted to scattered populations along 15 miles of the Middle Fork of the Willamette River whereas the Umpqua Oregon chub is still widely distributed. The decline in the Willamette drainage was more severe because changes in the physical and biological habitat were more severe when compared to the Umpqua drainage. The Willamette Oregon chub may be more sensitive to environmental degradations than the Umpqua Oregon chub. The difference in sensitivity to degradation is a result of ecological differences between Willamette and Umpqua Oregon chub. Willamette Oregon chub inhabited areas with primarily very little if any current, fed in the water column, and spawned in aquatic vegetation. Umpqua Oregon chub inhabited areas with primarily slow water velocities, fed on benthic prey, and spawned over gravel substrate. Because Willamette Oregon chub inhabit slackwater habitats they may be more sensitive to water velocity increases and exotic species, whereas Umpqua Oregon chub have a habitat refuge in relatively faster water velocity habitats. Willamette Oregon chub larval stages are described and illustrated. The following combination of characters distinguish Willamette Oregon chub larvae from other cyprinid larvae found in the Willamette drainage: 33-37 myomeres, preanal length of 52-61%, and absence of snout pigment. Willamette Oregon chub larvae generally congregated in nearshore areas, in the upper layers of the water column, in shallow water. They fed primarily in the water column, and ate primarily rotifers and cladocerans. / Graduation date: 1989

No description available.

My research has focused on the identification, assemblage dynamics, and horizontal distribution patterns of larval fishes around rocky reefs in the Gulf of California, Mexico. In Chapter One, I analyze a series of light-trap collections taken over 35 nights at San Carlos, Sonora. Nearly 14,000 larvae from 19 families were collected. The five most abundant families contributed 90% of the larvae and the top ten families contributed 99%. Larvae of non-pelagic spawners (gobiids, labrisomids, tripterygiids, chaenopsids, pomacentrids, and bythitids) dominated the collections. Larval catches ranged from 7.5 to 2330.3 larvae/45 min, but changes in catch rate were not related to changes in ambient moonlight. In contrast, the volume of zooplankton collected was correlated with moonlight intensity. Dynamics of the ten dominant fish families were highly variable, but in most cases a large proportion of the larvae were caught on just a few nights. Taxonomic and size selectivities were apparently less severe in my study than in previous Australian studies, and the use of light-traps should be explored further. In Chapter Two, I outline the prediction that larvae of small, non-pelagic spawning fishes should more frequently be retained over reefs during development than fishes with other combinations of body size and egg type, and I describe my research testing this prediction. I made about 160 collections of fish larvae with a light-trap and plankton net at 1, 20, and 100 m from rocky shorelines. These collections yielded 27,265 larvae from about 50 families. Based on larval size frequencies, near-reef concentration gradients, and abundances offshore, I identified four families that can complete development over the reef but also have larvae dispersed offshore (Clupeidae, Engraulididae, Gerreidae, and Haemulidae). In addition, I identified seven families that primarily develop over reefs and have few or no larvae dispersed offshore (Tripterygiidae, Chaenopsidae, some Labrisomidae, Dactyloscopidae, some Gobiidae, Gobiesocidae, and Bythitidae). Adults of these seven families are mostly small, non-pelagic spawners. Larvae from four taxa of larger non-pelagic spawners (Ophioblennius, Labrisomus, Balistes, and Pomacentridae) did not appear to develop over reefs. These findings are in accord with the prediction I made. Chapter Three is a preliminary guide to identification of Gulf of California blennioid larvae. Although blennioid larvae are poorly known and few species have been described, they are well represented (ca. 20,000 larvae from five families) in my collections taken near reefs in the Gulf. Illustrations of 20 species, and brief descriptions of key characters for these and several additional species, are provided. More detailed taxonomic studies on Gulf blenniid, dactyloscopid, tripterygiid, labrisomid, and chaenopsid larvae are in progress.

No description available.

No description available.

This study was undertaken to determine the effects of beryllium nitrate on regeneration in the tail of Rana Pipiens larvae. The tails were amputated approximately 3 rom from the tips. Some were then treated with different concentrations of beryllium nitrate (0.5 N, 0.7 N, and 1.0 N). Normal regeneration of untreated amputated tails was fulfilled in an orderly manner. In the animals treated with beryllium nitrate, general tissue regeneration was inhibited. Considerable degeneration was observed in all tissues of the tail stumps. Holfever, the elastic lamella of the notochordal sheath was stimulated to stretch, oftentimes breaking the continuity of the fibrous lamella. The elastic layer appeared highly ravelled within the degenerated tissues of the tail, and, in some cases, extended for 3 to 4 inches from the tail stump due to a break in the covering epithelium.

Poon, Chi-to, Geoffrey. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 115-125). / Acknowledgements --- p.I / Abbreviations --- p.II / Abstract --- p.III / Table of content --- p.IV / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Importance of growth enhancement in aquaculture --- p.1 / Chapter 1.2 --- Physiological effect of growth hormone --- p.1 / Chapter 1.3 --- Progress in teleost growth hormone research --- p.3 / Chapter 1.4 --- Grass carp and its aquaculture --- p.5 / Chapter 1.5 --- Route of administration of growth hormone --- p.8 / Chapter 1.6 --- Nomenclature of baculovirus --- p.9 / Chapter 1.7 --- Biology of baculovirus --- p.10 / Chapter 1.8 --- Control of gene expression of virus-infected cells --- p.13 / Chapter 1.9 --- Theme of the thesis --- p.14 / Chapter Chapter 2 --- Materials and Methods --- p.18 / Chapter 2.1 --- Synthesis and purification of primers --- p.18 / Chapter 2.2 --- Modification of gcGH cDNA by polymerase chain reaction (PCR) --- p.20 / Chapter 2.3 --- TA cloning of PCR product --- p.20 / Chapter 2.4 --- Purification ofDNA fragment from agarose gel by GENECLEAN´ёØ --- p.21 / Chapter 2.5 --- Recovery of low molecular weight DNA fragment from agarose gel --- p.22 / Chapter 2.6 --- Small scale preparation of plasmid DNA --- p.23 / Chapter 2.7 --- Large scale plasmid preparation by QIAGEN´ёØ --- p.24 / Chapter 2.8 --- Preparation of competent Escherichia coli JM109 for transformation --- p.25 / Chapter 2.9 --- Transformation of plasmid into competent Escherichi coli JM109 --- p.26 / Chapter 2.10 --- Cell culture of BmN cell line --- p.26 / Chapter 2.10.1 --- Preparation of TC-100 insect medium --- p.27 / Chapter 2.10.2 --- Preparation of Grace's medium --- p.27 / Chapter 2.11 --- Extraction of wild-type Bombyx mori nuclear polyhedrosis virus DNA --- p.28 / Chapter 2.12 --- Transfection of BmN cells with Bombyx mori nuclear polyhedrosis virus DNA by DOTAP´ёØ --- p.28 / Chapter 2.13 --- Agarose plaque assay --- p.29 / Chapter 2.14 --- Lifting of vius plaque onto nitrocellulose filter paper --- p.30 / Chapter 2.15 --- Synthesis of radiolabelled DNA probe --- p.31 / Chapter 2.16 --- Pre-hybridization and hybridization of recombinant virus DNA on nitrocellulose paper --- p.31 / Chapter 2.17 --- Purification of recombinant virus by dot-blot manifold --- p.33 / Chapter 2.18 --- Preparation of cell lysate from virus-infected BmN cells --- p.33 / Chapter 2.19 --- Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.34 / Chapter 2.19.1 --- Staining of the gel by Coomassie blue method --- p.35 / Chapter 2.19.2 --- Staining of the gel by silver staining method --- p.35 / Chapter 2.20 --- Determination of protein concentration by Bradford's method --- p.36 / Chapter 2.21 --- Determination of total protein concentration by Folin-Lowry method --- p.36 / Chapter 2.22 --- Detection of grass carp growth hormone by Western blotting --- p.37 / Chapter 2.23 --- Preparation of native recombinant grass carp growth hormone for iodination --- p.38 / Chapter 2.24 --- Iodination of recombinat grass carp growth hormone by IODO-GEN´ёØ --- p.38 / Chapter 2.25 --- Purification of radiolabelled recombinant grass carp growth hormone --- p.39 / Chapter 2.26 --- Radioimmunoassay (RIA) for detection of recombinant grass carp growth hormone --- p.40 / Chapter 2.27 --- Ammonium sulphate precipitation --- p.41 / Chapter Chapter 3 --- Vector Construction --- p.42 / Chapter 3.1 --- Components of parent vector pBM030 --- p.42 / Chapter 3.2 --- Construction of pBM-EE --- p.44 / Chapter 3.3 --- Constrcution of pBM-EX --- p.47 / Chapter Chapter 4 --- Results --- p.51 / Chapter 4.1 --- Construction and purfication of recombinant baculovirus --- p.51 / Chapter 4.2 --- Expression of recombinant grass carp growth hormone in BmN cells --- p.55 / Chapter 4.3 --- Expression of recombinant grass carp growth hormone in Bombyx mori larva --- p.62 / Chapter 4.4 --- Putative physical characteristics of the recombinant grass carp growth hormone --- p.67 / Chapter 4.5 --- Purification of the grass carp growth hormone in Bombyx mori larva --- p.69 / Chapter 4.5.1 --- Ammonium sulphate precipitation --- p.69 / Chapter 4.5.2 --- Gel filtration --- p.72 / Chapter 4.5.3 --- Hydrophobic interaction chromatography --- p.75 / Chapter 4.5.4 --- Anion exchange chromatography --- p.78 / Chapter 4.5.5 --- Reverse phase chromatography --- p.90 / Chapter Chapter 5 --- Discussions --- p.99 / Chapter 5.1 --- Merits of baculovirus expression system against other expression systems --- p.99 / Chapter 5.2 --- Basic design of the recombinant baculovirus transfer vector --- p.100 / Chapter 5.3 --- Potential for Mutation of the Baculovirus during Homologous Recombination --- p.101 / Chapter 5.4 --- Cleavage of Signal Peptide from the Expressed Protein --- p.103 / Chapter 5.5 --- Difference in recombinant gcGH expression levelin EE4-7 and EX3-16 --- p.103 / Chapter 5.6 --- Purification of recombinant gcGH protein --- p.106 / Chapter 5.6.1 --- Chromatographic behaviour of recombinant gcGH in Q-Sepharose column --- p.106 / Chapter 5.6.2 --- Problem of aggregation of recombinant gcGH --- p.107 / Chapter 5.6.3 --- Solvent system used in recombinant gcGH purification --- p.108 / Chapter 5.6.4 --- Protein denaturating effect of the solvent system --- p.109 / Chapter 5.6.5 --- Protein yield --- p.110 / Chapter 5.7 --- Problems and accuracy of radioimmunoassay --- p.110 / Chapter Chapter 6 --- Further study --- p.113 / Chapter Chapter 7 --- References --- p.115 / Appendix I --- p.126 / Appendix II: Construction of the Supervector --- p.127

The Drosophila larva is a suitable model to study olfaction due to its numerical simplicity. The peripheral olfactory system consists of just 21 pairs of olfactory sensory neurons (OSNs), each expressing one, or at most two classes of olfactory receptors (ORs) that define the receptive range of the OSN. Larvae produce robust behaviours to many odours and are easily genetically manipulated. Unlike audition, relatively little is known regarding olfaction due to its complex nature - most odours exist as multimolecular units that vary in their identity and structure, concentrations and proportions. Until recently, most olfactory research has focused on the processing of simple odours, which does not realistically model real-world odours. Presented here is one of the first in situ investigations of odour mixture processing in the Drosophila melanogaster larva. Processing of odour mixtures was explored using both electrophysiological recordings of the peripheral olfactory system and behavioural assays at the output of the system, and the effects of various factors on responses were also explored. w1118 larvae in which all OSNs were functional, and larvae with only a single class of OSN (using the Gal4-UAS expression system) were studied. At the peripheral level, mixture responses were never entirely transformed from the components, and were always as large as or greater than the response to the strongest component, and therefore the neuron was either 'seeing' just one or more than one of the components, respectively. Mixture responses across all OSNs were always additive, hypoadditive or partially suppressive, and there were no instances of synergistic or fully suppressive responses. Peripheral mixture responses were both OR- and component-dependent, as the same mixture was represented differently across OSNs. At the behavioural level, mixture responses were mostly additive, partially and fully suppressive and therefore not always predictable from the components. Interestingly, responses of larvae with only a single class of OSN were mostly predictable as there was no complexity of processing arising from the combinatorial code. When all OSNs were functional and the combinatorial code appropriately activated, mixture responses were more complex and unpredictable. Associative conditioning experiments revealed that larvae were unable to identify components from within a mixture, providing evidence that, at least at the behavioural level, mixture responses were probably synthetic, and therefore likely that interactions between the components occurred at some point along the processing pathway. Mixtures were often dominated by the component inducing the largest firing rate, and carbon chain length and vapour pressure influenced, to some degree, which component dominated. The nature of mixture responses were affected by concentration which is consistent with a model of receptor competition - at low concentrations mixture responses were additive, whilst at high concentrations responses were reduced compared to an additive response. In contrast, prior experience had little effect on peripheral responses to pure odours and mixtures, although rapid adaptation was observed during exposure. Exposure did have an effect on subsequent behavioural responses to pure odours and mixtures, providing evidence of central effects of adaptation. The data presented here provides evidence that mixture processing is extremely complex, with many factors influencing and affecting the way that the system responds to mixtures. This data reveals an unexpected complexity in a numerically simple system and with such'simple' complex odours, and indicates the likelihood of more complex responses when all OSNs are functional.

Orientador: Elizabeth Romagosa / Banca: Sérgio de Medeiros Ferraz / Banca: Sérgio Ricardo Batlouni / Resumo: Estudos para produção de formas jovens de peixes são fundamentais para o desenvolvimento da piscicultura e o manejo das populações naturais. Leporinus agassizii é apreciado nas distintas modalidades de pesca (comercial, artesanal, ornamental e esportiva), além de apresentar características desejáveis para a criação. Objetivou-se descrever o desenvolvimento embrionário e a densidade de estocagem de larvas do aracu-riscado, L. agassizii. Reprodutores foram submetidos a reprodução induzida por hipofisação, com a temperatura da água a 28,6 ± 0,7ºC, no Centro de Capacitação e Produção de Alevinos, pertencente ao Instituto Federal de Educação Ciência e Tecnologia, São Gabriel da Cachoeira, Amazonas, Brasil, no mês de setembro de 2014. Logo após a fertilização, os ovos foram mantidos em incubadoras (60L), com a temperatura média da água de 28,4 ± 0,7 ºC. Coletaram-se amostras de ovos em intervalos de 10 min, durante as primeiras três horas pós-fertilização (PF) e, posteriormente, em intervalos de 30min até a eclosão das larvas, para observação em estereomicroscópio equipado com câmera CMOS digital colorida, 10.0 MP e software para captura e análise de imagens (ISCapture). O efeito da densidade de estocagem de larvas do L. agassizii foi avaliado ao longo do 4º e 14º dias após a eclosão (DAE). Foram utilizadas 3600 larvas no 4º DAE, encontrando-se estas com o saco vitelínico totalmente absorvido, boca aberta e mantidas em jejum. As larvas foram submetidas às densidades de 5 (D5), 15 (D15) e 25 (D25) larvas.L-1, em caixas de polietileno (0,63 x 0,45 x 0,32 m), com 20 L de água. Utilizou-se um delineamento inteiramente casualizado com quatro repetições. As larvas foram alimentadas seis vezes ao dia, sendo cada refeição composta por náuplios de Artemia, na proporção 50 náuplios.larva-1 (4º ao 6º DAE), 100 (7º ao 9º DAE), 200 (10° ao 11º DAE) e 400 (12º ao 13º DAE) e por ração... / Abstract: Studies for the production of young fish shapes are key to the development of fish farming and the management of natural populations. Leporinus agassizii is appreciated in the different fishing methods (commercial, craft, ornamental and sports), and present desirable features for creation. This study aimed to describe the embryonic and larval stocking density of aracu-riscado, L. agassizii. Players underwent reproduction induced hypophysation, with the water temperature at 28.6±0.7 °C, the Centro de Capacitação e Produção de Alevinos belonging to the Instituto Federal de Educação, Ciência e Tecnologia, São Gabriel da Cachoeira, Amazonas, Brazil, in September 2014. After fertilization, the eggs were kept in incubators (60 Litre), with the average water temperature of 28.4±0.7 °C. Samples were collected 10 min intervals on eggs during the first three hours after fertilization (AF) and thereafter at intervals of 30 minutes until the outbreak of the larvae, for observation in stereo equipped with digital color CMOS camera, 10.0 MP and software to capture and analyze images (ISCapture). The effect of larval stocking density of L. agassizii was assessed over 4th and 14th days after hatching (DAH). 3600 larvae were used in the 4th DAH, meeting these with the yolk sac fully absorbed, mouth open and fasted. The effect of larval stocking density of L. agassizii was assessed over 4th and 14th (DAH). 3600 larvae were used in the 4th DAH, meeting these with the yolk sac fully absorbed, mouth open and fasted. The larvae were subjected to density of 5 (D5), 15 (D15) and 25 (D25) larvas.L-1, in polyethylene boxes (0.63 x 0.45 x 0.32 m) with 20 Litre of water. We used a completely randomized design with four replications. The larvae were fed six times a day, each meal consisting of Artemia in the proportion 50 náuplios.larva-1 (4th to 6th DAH), 100 (7th to 9th DAH), 200 (10th to 11th DAH) and 400 (12th to 13th DAH) and commercial diet ... / Mestre

No description available.