Thesis (Ph. D.)--University of Michigan, 1937. / Thesis note on label attached to p. 203. "Reprinted from volume 66 (1936) Transactions of the American Fisheries Society." "Literature cited": p. 210.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1983. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 196-202).

Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page; viewed on June 24, 2009. Major professor: James Vilkitis, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture." "June 2009." Includes bibliographical references (p. 48-50). Also available on microfiche.

Thesis (M.E.S.)--The Evergreen State College, 2008. / Title from title screen (viewed 2/25/2009). Includes bibliographical references (leaves 32-33).

Flavobacterium psychrophilum (Fp), the aetiological agent of rainbow trout fry syndrome (RTFS) and bacterial cold-water disease (BCWD), is responsible for significant mortalities and economic losses in the salmonid aquaculture industry worldwide. Currently, there is no effective commercial vaccine against RTFS available, and the treatment of the disease depends on the oral administration of a wide range of anti-microbial compounds, some of which have proven ineffective. With unsuccessful disinfection procedures, possibilities of antibiotic resistance developing and no commercial vaccine available, there is an increased need to rapidly detect Fp and reduce mortalities in the industry by improving control measures in the farm system. The aim of this thesis was to investigate possible sources of Fp in a rainbow trout fry farm system and to use this data to develop strategies to reduce the prevalence of the pathogen with this farming system. Novel assays to detect Fp (loop-mediated isothermal amplification; LAMP), quantify Fp (quantitative PCR; qPCR) and to detect the fishes’ host response to Fp (Luminex™) were developed, and then used alongside bacterial culture and nested PCR to determine the prevalence of Fp on a commercial fish farm. Four batches of eggs from 3 different geographic sources were collected on arrival at the farm and tested for the prevalence of Fp. Fry from these batches were monitored as they grew and were moved to different sites at the farm. Kidney, spleen and blood were collected at 3 different life stages from the fry, until they were sold for ongrowing by the farm. Water samples from the inlet, outlet and fry tanks were collected at each sampling point. PCR analysis and bacteriology were the two main methods selected for screening the eggs and fry tissue for Fp. All sources of eggs were found to be positive for Fp with prevalences ranging from 1.1 % - 1.9 % and there was a significant increase in prevalence over time for all 4 batches of eggs ranging from 19.8 % - 34.6 % by the final life stage sampled. There was also a substantial difference in the numbers of fry samples positive for Fp depending on whether nested PCR or bacterial culture were used, as well as the organ (kidney or spleen) tested. This highlighted the importance of sampling both organs rather than just the one. Nested PCR was more sensitive than culture with 13 % of the fry samples reported as Fp positive, by sampling both the kidney and spleen collectively, while only 5 % were Fp positive by bacteriology. The levels of Fp in all samples could not be quantified by qPCR due to limits in the sensitivity of the assay. For those samples that were quantified at the levels of Fp detected by qPCR ranged from 3.38 x 104 well-1 - 2.07 x 106 well-1 genome copies in egg samples; from 3.38 x 103 well-1 – 3.07 x 107 well-1 genome copies well-1 in tissue samples (spleen or kidney), and from 7.89 x 103 – 7.22 x 104 genome copies well-1 in water samples. The sensitivity of the standard curve was limited to 103 copies well-1 and following optimisation of the assay the annealing temperature was decreased by 1˚C to 62°C to reduce the cross-reactivity to negligible levels, though this reduced the sensitivity of the assay even further to 104 copies well-1. The detection limits by qPCR obtained by spiking samples with known amounts of Fp were 192 CFU mg-1 from egg samples, 184 CFU mg-1 from fry tissue samples, and 220 CFU ml-1 from water samples,. The sensitivity of the LAMP assay determined by spiking egg, kidney, spleen and water samples was 18 CFU mg-1, 22 CFU mg-1, 25 CFU mg-1 and 16 CFU ml-1, respectively. The latter was similar to, though not as sensitive as nested PCR. Nested PCR limits determined by spiking egg, kidney, spleen and water samples were 14 CFU mg-1, 11 CFU mg-1, 13 CFU mg-1 and 11 CFU ml-1. No cross-reactivity was found with any bacteria including other Flavobacterium species with nested PCR but cross-reactivity with other Flavobacterium species were found with both qPCR (1.51 % with Flavobacterium aquatile and 0.30 % with Flavobacterium johnsoniae) and LAMP. The LAMP assay showed slight cross-reactivity with Flavobacterium columnare and Flavobacterium branchiophilum. A novel Luminex™ assay was also developed and optimised, using microspheres coated with Fp, to detect antibodies to Fp in the serum of the fry. The Luminex™ allowed small volumes of serum from individual fry to be used to evaluate antibody response as an indirect method to determine exposure to and infection by Fp. A large number of fry from all 4 batches (88% - 94%) of eggs were found to contain anti-Fp antibodies though it still remains to be determined whether the antibodies were specific to Fp. From the work carried out in this study, it can be concluded that whether eggs are carrying Fp inside and/or on their surface, it should be possible to reduce the prevalence of Fp in farm systems by regularly screening the broodstock, eggs and fry. Supply of Fp-free eggs and milt is essential to reduce the reservoir of Fp on farms. Both the qPCR and LAMP assay require further optimisation but they do offer potential for the future screening of Fp at farm sites and in the laboratory. Future control measures for RFTS should include the screening of broodstock and eggs by sensitive methods so that Fp-free seed can be supplied to farms. This, alongside effective disinfection procedures, rigorous husbandry practices and future vaccine development will all be required to manage this very significant fish disease.

The nutritional value of dietary fibre for rainbow trout, Salmo gairdneri was investigated using juvenile fish (lO-30g) maintained in freshwater at ambient temperatures under a natural photo period. A preliminary experiment was conducted using five purified dietary fibre sources, namely, a~cellulose, lignin, lignosulphonate, galactomannan and chitin ·which varied in physical, chemical and textural characteristics. A commercially available, powdered polyethylene was also used as an inert control ingredient and all sources of fibre were included at a, realistically low level of 5'% in separate semi-purified diets. Although there were no significant differences in the growth of fish at the end of the 10-week trial, several nutritional parameters were affected for rainbow trout fed the different experimental treatments. Mean daily food intake was re"d uced for trout receiving the lignin, chitin and galactomannan diets compared to the polyethylene control. Similarly the food conversion ratios (FeR) and protein efficiency ratios (PER) were relatively inferior for diets containing chitin and galactomannan compared to the lignosulphonate treatment. Maximum net dietary nitrogen utilization was obtained for the polyethylene control t' ... ra ~on whilst lower values were again observed with chitin and galactomannan. Apparent dry matter (DM) and nitrogen digestibility coefficients however were in close agreement for each of the dietary treatments except for the lignin diet which was poorly digested. Generally the results implied that the properties of chitin and galactomannan were worthy of further study at higher inclusion levels and in different physical states. A specific·investigation in which 0, 5, 10, 15 and 20% additions of a purified a-cellulose replaced dietary starch in separate experimental di e t s f a~'1 e d to produce any significant changes in the growth performance of trout and only slightly influenced nutrient utilization at the higher 15 and 20% inclusion levels. Negative digestibility coefficients for the 'unavailable' carbohydrate fraction of diets calculated from the 'total' and 'available' carbohydrate contents of diet and faecal samples was considered to be evidence of the non-nutritive and bulking qualities of a-cellulose. Growth and digestibility trials were then undertaken to examine the effects of including different levels (10 and 20%) and particle size ranges (45-500, 500-1000 microns) of chitin (poly-Nacetyl- D glucosamine) as a natural source of dietary fibre for trout. In a similar experiment, graded amounts of galactomannan polysaccharide (0, 10 and 20%) were added to moist pelleted diets to examine the long term effects of feeding a gel-type fibre characteristic' of many commercially available binding agents. Negative digestibility coefficients for both chitin and galactomannan based on specific biochemical measurements together with the failure to detect any chitinase activity in stomach and intestinal tissue was confirmation of the inability of rainbow trout to degrade and utilize these materials. Coarse grades of chitin at the 10 and 20% levels impaired food intake, growth performance and nutrient utilization as shown by the Poorer FCR, PER, net nitrogen utilization and digestibility coefficients compared to the diets containing finely ground chitin or the α-cellulose control treatment. Similar findings were obtained with increasing additions of galactomannan and there were associated reductions in the serum glucose and protein concentrations with each increment of dietary galactomannan. The final carcass compositions of fish were also affected by the gel fibre which caused a significant reduction in the tissue lipid content and an inverse trend in moisture content compared to trout receiving an a-cellulose control diet. Further investigations using a sacrificial method to follow and quantify the passage of food through the gastrointestinal tract revealed that the physical properties of fibre such as particle size composition, water retaining capacity and viscosity were among several factors which modified gastric evacuation and digestion rates in rainbow trout. From the predicted gastric emptying times (GET), it was apparent that coarsely graded chitin (20%) and both 10 and 20% inclusions of galactomannan considerably increased the residence time of the gastrointestinal contents compared to finely ground chitin and a control diet without added fibre. Although an exponential relationship was found to best describe the stomach emptying profiles obtained, linearization of the data was achieved by applying surface area and volume dependent mathematical models which emphasized the importance of these physical factors. The combined nutrition and physiological studies supported the contention that fibre is the non-nutritive part of the diet, but it Was concluded that the level and nature of the fibrous material has· important consequences on the processes controlling food intake and the efficiency of digestion, which in turn may affect the assimilation of nutrients and the performance of growing rainbow trout.

Thesis (Ph.D.)--Aberdeen University, 1989. / Title from web page (viewed on Mar. 4, 2010). Accompanying offprints stored in end pocket. With: A combined radio and acoustic transmitter for fixing direction and range of freshwater fish (RAFIX) / J.D. Armstrong ... et al. J. Fish Biol. 33, 879-884. With: An acoustic telemetry system for monitoring the heart rate of pike, Esox Lucius L. and other fish in their natural environment / J.D. Armstong ... et. J. Exp Bio 1989: 143, 549-552. With: Effects of implanted dummy transmitters on mortality, growth and tissue reaction in rainbow trout, Salmo gairdneri / M.C. Lucas . J. Fish Bio. 35, 577-587. Includes bibliographical references.

Thesis (Ph.D.)--McMaster University, 2003. / Supervisor: D.G. McDonald. Includes bibliographical references (leaves 213-224). Also available via World Wide Web.

Thesis (M.S.)-Oregon State University, 1988. / Includes bibliographical references (leaves 74-80). Also available via the Internet.

The research assessed the potential of developing a selective breeding programme for the UK rainbow trout industry. Levels of genetic variation at 12 microsatellite loci were first compared in seven different commercial strains. The Observed heterozygosity ranged from Ho = 48.1% in a gold rainbow trout strain (GTR) to Ho = 66.4% in a newly derived broodstock population constructed from a number of different sources (GIT). The Expected Heterozygosity (He) was highest in GIM1 (He= 79.5%) and lowest in the GTR strain (He = 56.9%). The Effective number of alleles (Mae) showed that the GIM1, GIM2, GIM3, and GIT strain (5.4; 5.2; 4.8; 4.2) were significantly more variable than the other strains and that GTR strain had the lowest value (2.5). There appears to be substantial genetic variability within the commercial United Kingdom rainbow trout strains surveyed in this study. This appears to be the case despite very different management histories and levels of record keeping. The strains appear to be genetically distinct (based on population genetic analyses), though the reasons for this remain unclear (and possibly unanswerable given the poor records kept by the different companies). The Glenwyllin farm strains (GIM) were chosen to form the base population for the project because of their high genetic variability, disease free status and because the farm produced around 20 million ova per year, so any genetic gains would have a widespread impact. The farm has an early (Strain A) and a late spawning (Strain B) and these were mated in a partial factorial design, 20 females and 20 neomales per strain (A & B) were chosen on the basis of maturity and gamete quality in November 2002 so that each male was crossed to 4 females (2 in the same strain and 2 in the other), a total of 160 families were created. All broodstock were biopsied to enable them to be genotyped. The families were reared separately up to the eyed stage at which point the eggs from each family were divided into three to generate three communal replicate populations. One of these was sent to a fingerling producer (Iwerne Spring) for ongrowing to fingerling size and formed the basis of a commercial production trial at Test Valley Trout farm (TVT) in Hampshire. When the fish reached an average weight of 5 g they were transferred from Iwerne Spring to TVT and 1500 were randomly selected, PIT tagged and biopsied to enable them to be assigned to their family using 11 multiplexed microsatellite loci. Parental assignment was based on exclusion (FAP) but the results were compared with another parental assignment based on likelihood (PAPA). Of the 1500 offspring (OIM) PIT tagged 1242 82.8% could be assigned to a single family utilizing different combinations of more than 6 loci (6 to 11). The growth of the 1500 OIM fish was tracked throughout the grow out period before they were finally harvested and fully processed. The results of OIM strain at the end of the trial period were mean weight of 415.5 g, and a mean length of 314.5 mm. The visual measurement of colour gave a mean flesh colour values of 26.01 on the 20-34 scale (SalmoFan™), and 11.0 with the colotimetry evaluation of colour (a*). The heritability results for the IOM strain were 43 ± 9% for weight, 42 ± 9% for gutted, and 28 ± 8% for length. The heritability estimates for the visual colour variables were 19 ± 7% and when using the colorimeter, the red chromaticity (a*) heritability was 14 ± 6%. Therefore, the heritability results of the IOM strain indicate that there are opportunities of substantial and rapid improvement of the growth rate and flesh colour traits. Also no line effects were observed or indications of non-additive genetic variation. In contrast to these last results, the overall survival of the GIM strain from the time of the physical tagging with PIT until harvest was 52.8%, and survival heritability was extremely low, 3 ± 2%, hardly significant.