Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 95-115).

Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references.

Thesis--Leiden. / On spine: Energy metabolism of goldfish. Errata sheet inserted. In English with summaries and part of title-page in Dutch. Includes bibliographical references.

Intensive grow-out of goldfish, Carassius auratus (L.), larvae and juveniles in closed recirculating systems requires the control of environmental conditions and feeding. This study investigated the effect of different diets, environmental condition and feeding level on growth, development and survival of goldfish larvae and juveniles. Prey preference for Artemia nauplii or decapsulated Artemia cysts as well as agonistic behaviour was recorded. The micrometer device used to measure mouth-gape was shown to produce accurate measurements which could be used to estimate the maximal particle size that can be ingested by goldfish larvae of a particular age. Goldfish completed metamorphosis earlier with an increased feeding level of Artemia cysts and by making the cysts more accessible to the fish using up-welling water movement. Morphometric plasticity in goldfish larvae was exhibited within two weeks of growth and it may be possible to induce changes in morphology by manipulating diet and rearing environment. Fish that fed on moving prey items had a significantly larger mouth-gape than those that browsed cysts from the tank bottom or dry food items. The development of mouth-gape was not affected by the feeding level of cysts. Condition factor increased with an increase in the number of cysts fed per fish per day. Goldfish larvae and juveniles grew faster and had a higher survival when fed on decapsulated Artemia cysts than on instar I Artemia nauplii or a mixed live/dry diet of Artemia nauplii and dry food. Feeding at least 155 cysts per fish per day, in tanks with upwelling water movement, gave the best growth and survival and the smallest size variation. In addition, cysts remained available to the fish for longer periods, and were easier to prepare and feed. Goldfish larvae preferred decapsulated Artemia cysts to nauplii and rejected fewer prey items as they grew older. The frequency of agonistic behaviour increased as fish grew but no cannibalism was recorded for cyst-fed fish. This study showed that decapsulated Artemia cysts are a good alternative to Artemia nauplii as a diet for larval goldfish. Good growth and high survival was achieved for cyst-fed goldfish larvae and juveniles at 23 ± 1.5°C and at an initial stocking density of 12 fish per litre. This research also contributes to an understanding of feeding behaviour and attempts to minimise under- or over-feeding of Artemia cysts in order to reduce grow-out costs due to the high value of the feed type.

CTMinimum and CTMaximum were measured in 620 goldfish to determine if biotic factors, in particular starvation, condition factor and size, affect temperature tolerance. Twenty-eight days of starvation adversely affected both upper and lower temperature tolerance. Condition factor was related to upper but not lower temperature tolerance.

Thesis (M. Sc.), Memorial University of Newfoundland, 1999. / Bibliography: p. 64-70.

In general, the objective of the present study was to incorporate some of the new psycho-biological approaches, with the theories propagating their use, in studying the phenomena of long-term memory in the goldfish.

by Chan Yuk Hang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 120-137). / Acknowledgments --- p.i / Table of Content --- p.ii / List of Tables --- p.vi / List of Figures --- p.viii / List of Abbreviations --- p.xi / Chapter CHAPTER 1 --- Literature Review Page / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- "Overview of the Structures of GH, PRL and SL" --- p.2 / Chapter 1.3 --- Physiological Significance of the Hormones in Teleost --- p.12 / Chapter 1.3.1 --- Growth Hormone --- p.12 / Chapter 1.3.2 --- Prolactin --- p.12 / Chapter 1.3.3 --- Somatolactin --- p.13 / Chapter 1.4 --- Structure - Function Relationship and Receptor Binding Activities --- p.15 / Chapter 1.5 --- Aims of Thesis --- p.23 / Chapter CHAPTER 2 --- General Methodology / Chapter 2.1 --- Materials --- p.25 / Chapter 2.2 --- DNA manipulation methods --- p.28 / Chapter 2.2.1 --- Polymerase Chain Reaction (PCR) --- p.28 / Chapter 2.2.2 --- Ethanol Precipitation of DNA --- p.29 / Chapter 2.2.3 --- Agarose Gel Electrophoresis of DNA --- p.29 / Chapter 2.2.4 --- Sephadex G-50 Spun Column --- p.30 / Chapter 2.2.5 --- Nick Translation --- p.30 / Chapter 2.2.6 --- Small Scale Plasmid Preparation by Alkaline Lysis Method --- p.31 / Chapter 2.2.7 --- Large Scale Plasmid Preparation Using Magic´ёØ Maxipreps DNA Purification System (Promega) --- p.32 / Chapter 2.3 --- DNA Cloning Methods --- p.33 / Chapter 2.3.1 --- Blunt-end Ligation of PCR Product to pUC18 Vector --- p.33 / Chapter 2.3.1.1 --- Preparation and Transformation of E. coli (JM109) Competent Cell --- p.33 / Chapter 2.3.1.2 --- Recovery of DNA from Agarose Gel Using the Sephaglas Bandprep Kit (Pharmacia Biotech) --- p.34 / Chapter 2.3.1.3 --- Kinasing Reaction --- p.34 / Chapter 2.3.1.4 --- Klenow Fill-in Reaction and Ligation of DNA Fragments --- p.35 / Chapter 2.3.2 --- Screening of Lambda Phage cDNA Library --- p.35 / Chapter 2.3.2.1 --- Preparation of Host Cell for Screening of Lambda Phage cDNA Library --- p.35 / Chapter 2.3.2.2 --- Phage Stock Tittering --- p.36 / Chapter 2.3.2.3 --- Plaque Lifting and Fixation on Nylon Membranes --- p.36 / Chapter 2.3.2.4 --- Library Screening by Hybridization --- p.37 / Chapter 2.3.2.5 --- In vivo Excision --- p.37 / Chapter 2.4 --- Nucleotide Sequence Determination using Dideoxy Nucleotide Chain Termination Method --- p.38 / Chapter 2.5 --- Protein methods --- p.39 / Chapter 2.5.1 --- Bicinchoninic Acid (BCA) Assay --- p.39 / Chapter 2.5.2 --- Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.40 / Chapter CHAPTER 3 --- Isolation and Characterization of cDNA Clones for Goldfish Prolactin / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.2 --- Methods --- p.43 / Chapter 3.2.1 --- Preparation of Hormone Specific DNA Probes by PCR Cloning --- p.43 / Chapter 3.2.2 --- Construction of Goldfish Pituitary cDNA Library --- p.44 / Chapter 3.2.3 --- cDNA Library Screening for Hormone Specific cDNAs --- p.44 / Chapter 3.2.4 --- Restriction Enzyme Digestion of the cDNA Clones and Subcloning of the Restriction Fragments --- p.45 / Chapter 3.2.5 --- Nucleotide Sequences Determination using Dideoxy Nucleotide Chain Termination Method --- p.46 / Chapter 3.2.6 --- Southern Analysis of the Goldfish Genomic DNA --- p.47 / Chapter 3.2.7 --- Northern Blot Analyses of Goldfish Pituitary Total RNA --- p.47 / Chapter 3.3 --- Results --- p.49 / Chapter 3.3.1 --- Screening of the Library and Characterization of the Clones --- p.49 / Chapter 3.3.1.1 --- Analyses of the cDNA Clones --- p.49 / Chapter 3.3.1.2 --- Cross Hybridization Reactivity --- p.57 / Chapter 3.3.2 --- Genomic Southern Blot Analyses --- p.58 / Chapter 3.3.3 --- Gene Expression of the Pituitary Hormones - Northern Blot Analyses --- p.61 / Chapter 3.4 --- Discussion --- p.64 / Chapter 3.4.1 --- Cross Hybridization Reavtivities of the Probes to the Hormone cDNA Clones --- p.64 / Chapter 3.4.2 --- Structural Analyses of the Hormone cDNA Clones --- p.65 / Chapter 3.4.2.1 --- Growth Hormone --- p.65 / Chapter 3.4.2.2 --- Prolactin --- p.68 / Chapter 3.4.2.3 --- Somatolactin --- p.70 / Chapter 3.4.3 --- Secondary Structure Prediction --- p.72 / Chapter 3.4.4 --- Genomic Southern Analyses --- p.78 / Chapter 3.4.5 --- Pituitary Expression of Goldfish Hormone mRNAs --- p.79 / Chapter 3.5 --- Conclusion --- p.81 / Chapter CHAPTER 4 --- "Expression of Recombinant Goldfish Growth Hormone, Prolactin and Somatolactin in Escherichia coli (E. coli)" / Chapter 4.1 --- Introduction --- p.82 / Chapter 4.2 --- Materials and Methods --- p.83 / Chapter 4.2.1 --- Materials --- p.83 / Chapter 4.2.2 --- Construction of Expression Vectors Carrying the Hormone Coding Regions --- p.84 / Chapter 4.2.3 --- Pilot Expression Experiment to Determine Kinetics of Expression --- p.86 / Chapter 4.2.4 --- "Large Scale Expression and Purification of Recombinant Hormones by Ni2+-NTA Affinity Column (ProBond´ёØ column, Invitrogen)" --- p.86 / Chapter 4.2.5 --- Western Blotting of the Recombinant Hormones on Polyvinylidene Fluoride (PVDF) Membrane --- p.87 / Chapter 4.2.6 --- Dot Blot Immobilisation of the Recombinant Hormones on Nitrocellulose Membrane --- p.88 / Chapter 4.2.7 --- Detection of the Blotted Protein by Enzyme-linked Immunodetaction Method --- p.88 / Chapter 4.3 --- Results --- p.90 / Chapter 4.3.1 --- Construction of the Expression Vectors --- p.90 / Chapter 4.3.2 --- Expression of the Recombinant Hormones --- p.97 / Chapter 4.3.3 --- Partial Purification and Analyses of the recombinant Hormones --- p.97 / Chapter 4.4 --- Discussion --- p.105 / Chapter 4.4.1 --- Construction of the Expression Vectors --- p.105 / Chapter 4.4.2 --- Expression of the Recombinant Hormones --- p.108 / Chapter 4.4.3 --- Partial Purification and Characterization of the Recombinant Hormones --- p.109 / Chapter 4.5 --- Conclusion --- p.114 / Chapter CHAPTER 5 --- General Discussion --- p.115 / References --- p.120

Prebiotic compounds comprise a group of dietary supplements defined as nonviable food ingredients that are selectively metabolized to favor beneficial intestinal bacteria. Such bacteria may confer various desirable effects including enhanced disease resistance and nutrient availability to the host. This study examined the effects of four prebiotics, GroBiotic®-A (a mixture of partially autolyzed brewers yeast, dairy ingredient components and dried fermentation products), mannanoligosaccharide (MOS), galactooligosaccharide (GOS), and the fructooligosaccharide (FOS) inulin on digestibility of soybean-meal-based diets by goldfish. A basal diet was formulated so that 50% of the protein was provided by soybean meal and the other 50% was from menhaden fishmeal. Each prebiotic was supplemented to the basal diet at 1% by weight. A diet containing all of its protein from menhaden fish meal also was prepared as a control diet. Chromic oxide was added to the diets at 1% as an inert marker. Each diet was fed to adult goldfish in duplicate 110-L iv aquaria for a total of 8 weeks. The dried fecal material from each aquarium was pooled over time and analyzed for protein, lipid, organic matter and chromium in order to compute coefficients of apparent digestibility. Genomic DNA of gut microbiota also was isolated from the fecal samples of goldfish fed the various diets and subjected to polymerase chain reaction (PCR) using bacteria-specific PCR primers to conserved regions flanking the variable V3 region of 16S rDNA. Then, denaturing gradient gel electrophoresis (DGGE) of the resulting amplicons was conducted as a means of assessing diversity of microbiota in the gastrointestinal (GI) tract. Results of the present study revealed that none of the prebiotics affected apparent digestibility coefficients of the soybean-meal-based diet compared to the basal diet, although the diet supplemented with MOS consistently yielded the lowest values. In addition, goldfish digested the soybean-meal-based diets as well as the control diet. DGGE analysis revealed no differences in microbiota of goldfish fed the various prebiotics. These results are in contrast to those obtained with carnivorous fish species such as the red drum (Sciaenops ocellatus) in which the prebiotics increased digestibility coefficients of soybean-meal-based diets and altered GI tract microbiota.

Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 72-80).