Three hundred rainbow trout from each of two strains (Wytheville and the Soap Lake) were exposed in equal numbers to three non-overlapping wavebands of light (red, green, blue). One hundred fish from each strain were used as a control. These fish were exposed to unfiltered light of intensity equal to that of the three spectral treatments (21.4 lux). All fish were exposed to continuous light of the assigned experimental spectra for 53 days. Fish were fed trout chow twice daily at a rate previously found to maximize growth and efficiency. This feeding rate was determined by consulting hatchery records and the feeding charts developed by Haskell (1959). Mean length and mean weight of test animals may be affected by the rearing of individuals under specific wavebands of light (α = .001). Fish grown under blue or green light had the greatest mean length and fish grown under control or green light had the greatest mean weight while those reared under red light had the lowest mean length and mean weight. Although differences in coefficient of condition, yield, ferd conversion ratio, and survival were not Significant between light treatments (α = 0.05) in my study, significant differences may possibly be found in studies with a larger sample size. Although high variability and small sample size limit interpretation, this study suggests that certain light treatments used in conjunction with certain strains of fish could improve hatchery production. / Master of Science

Strains evaluated were Ennis (EN, domestic), Fish Lake (FL, wild), Mcconaughy (MC, wild), FGL Standard Winter (SW, domestic), and Sand Creek (SC, semiwild). In 1981, four Virginia put-and-take streams were stocked with 150 and 50 of each strain in March and May, respectively. Creel and electrofishing surveys were conducted to determine harvest, movement and survival after fishing. A reference (unfished) stream was also selected and stocked with 50 of each strain, and electrofishing surveys were conducted to determine survival, growth and movement. SW and EN strains were caught by anglers primarily during opening weekend (April 4-5, 1981), while the FL and SC strains were caught throughout the creel survey period. The MC strain was consistently lowest for total estimated harvest, while the SC and SW strains were equally high in total estimated harvest. Significant differences occurred in the proportional relationships of strain harvests among streams. May harvest results generally corroborated April results, except that significant differences among streams were not found. Greater survival for strains with low harvests during April was not evident in fished streams. Natural mortality rates in the reference stream did not differ significantly among strains between May 20 and October 22, 1981. Change in average length of the strains over four months in Spring Branch ranged from -4.3 mm for EN to +18.9 mm for SW. Percentage of stocked biomass of the SW strain remaining after five months (20.8%) in the reference stream was more than twice that remaining for the EN (9.6%) and SC (9.4%) strains. No significant differences in downstream movement, and no significant upstream movements, were observed for strains in the fished and reference streams. / Master of Science

Thesis (MPhil)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: trout was conducted at the Jonkershoek trout research station of the Division of Aquaculture, University of Stellenbosch. Treatments consisted of ten experimental diets containing increasing levels of Spirulina (0%, 0.05%, 0.1%, 0.15%, 0.3%, 0.6%, 1.25%, 2.5%, 5% and 10%). The data was analyzed through means of a one-way ANOVA and Tukey’s pair wise comparison test for significant differences between treatments for the various parameters of flesh pigmentation and growth. The results indicates that the inclusion of Spirulina in the diets of rainbow trout will cause a undesirable yellowing of fillets, particularly at levels of inclusion at 5 percent and above, which may limit its use in diets for rainbow trout. There was an inconsistent increase in b* (yellowblue) and Chroma values with increasing levels of Spirulina inclusion, which may indicate the deposition of carotenoids (yellow-orange colour range) instead of the desired deposition of xanthophylls (pink-red colour range) in the flesh of the rainbow trout. This increase in b* (yellow-blue) values was significantly higher (P<0.05) at inclusion levels above 5 percent. Spirulina had no significant effect on weight gain of rainbow trout at any level of inclusion. No significant differences (P>0.05) were observed in any of the other production performance parameters (growth rate, feed intake, feed conversion ratio, viscerosomatic index, hepatosomatic index, and liver lipid content) that were evaluated. Low mortality rates were observed with no significant differences between treatments. A trend of decreased feed intake with increased levels of Spirulina inclusion became significant at the 2.5 percent level of inclusion, caused by deterioration in the palatability of the feed. A significantly higher dress-out percentage was observed at levels of Spirulina inclusion above 5 percent. A trend of decreased liver lipid content with increased Spirulina inclusion was observed, though not significant at any level of Spirulina inclusion. This observation justifies further investigation because of its potential to improved carbohydrate metabolism in carnivorous fish Results confirm that up to 10% Spirulina can effectively replaced soybean meal in the control diets for rainbow trout while simultaneously improving carcass dress-out at high inclusion levels. / AFRIKAANSE OPSOMMING: rantsoen van reënboog forel te evalueer. Die eksperiment is opgestel by die Akwakultuur Divisie, van die Universiteit van Stellenbosch, se navorsingstelsel in Jonkershoek, buite Stellenbosch. Reënboog forel (Oncorhynchus mykiss) vingerlinge van gemiddeld 20 gram is gebruik en ingedeel in 20 ronde tenks volgens kommersieële digthede (250 per tenk). Die rantsoene is gemeng met verskeie vlakke van Spirulina insluiting (0%, 0.05%, 0.1%, 0.15%, 0.3%, 0.6%, 1.25%, 2.5%, 5% en 10%). Twee herhalings van elke rantsoen is gevolg vir ‘n periode van 3 maande. Die vis is ad lib (volgens behoefte) gevoer, drie maal per dag. Daar was ‘n neiging tot ‘n verhoging in b* (geel-blou) en Chroma waardes met verhoogde insluitingsvlakke van Spirulina. Hierdie is wel ‘n aanduiding van die deponeering van karoteen, maar val in die geel-oranje kleur reeks en is nie die verlangde pienk-rooi (xantofil) kleur in die spier weefsel van die vis nie. Die verhoging in b* (geel-blou) waardes was statisties betekenisvol (P<0.05) bo die 5% insluitings vlak. In vergelyking met die kontrole (0%) rantsoen, was daar geen betekenisvolle massa toename na afloop van die proef tussen die verskeie behandelings nie. Behalwe vir ‘n verskil in voer inname, was daar geen statisties betekenisvolle verskil (P>0.05) waarneembaar tussen die verskillende behandelings ten opsigte van die verskeie produksie prestasie parameters nie. Daar was wel ‘n afnemende neiging in voer inname met verhoogde vlakke van Spirulina wat betekenisvol geraak het bo 2.5% insluitingsvlak. Smaaklikheid kan die moontlike rede hiervoor wees. Baie lae mortaliteite is ervaar by al die insluitings vlakke. Daar was ook ‘n neiging in hoër uitslag persentasie by verhoogde insluitingsvlakke van Spirulina wat betekenisvol geraak het bo 5 % insluiting. ‘n Afnemende vlak van lewer lipied inhoud is waargeneem maar was nie betekenisvol by enige van die insluitingsvlakke nie. Resultate van die proef dui daarop dat 10% Spirulina insluiting effektief kan dien as ‘n gedeeltelike plaasvervanger vir soyaboon meel in forel rantsoene. Die hoër uitslag persentasies hou belofte in. Die onverlangde vergeeling van die filette mag die gebruik van Spirulina beperk by reënboog forel rantsoene veral bo 5 % insluitings vlakke. Die verlaging in lewer lipied vlakke by ‘n verhoging van Spirulina insluiting regverdig vêrdere navorsing oor die potensiaal van Spirulina om die metabolisme van koolhidrate te verbeter by karnivoor visspesies.

Indole-3-carbinol (I3C) inhibits chemically induced tumor formation in rodents and rainbow trout. This study examines the effect of I3C and its analog, indole-3-acetonitrile (I3N) on xenobiotic-metabolizing enzyme systems. The modulation of these enzyme systems have been shown to have significant effects on the interaction of chemical carcinogens and cellular constituents. Rainbow trout were fed 500, 1000 and 2000 ppm dietary levels of I3C and 50, 500 and 1000 ppm dietary levels of I3N for 8 days. β-napthoflavone (BNF), which is also an effective anticarcinogen in the trout, was fed at a 500 ppm dietary level and was used as a positive LM4b (a cytochrome P-450 isozyme) inducing control. Enzyme activities assayed were: ethoxyresorufin-O-deethylase (EROD), ethoxycoumarin-O-deethylase (ECOD), glutathione S-transferase (GST), and uridine diphosphoglucuronosyl transferase (UDPGT). Total cytochrome P-450 content was determined spectrophotometrically by the CO reduced method. The specific P-450 isozymes, LM2 and LM4b, were detected quantitatively using the western blot method. The BNF diet induced EROD and ECOD activities by an average of 17 fold and 5.5 fold, respectively. Total P-450 content was increased 2-fold; the P-450 isozyme LM4b was induced more than 5-fold, but LM2 content remained unchanged. This diet increased UDPGT activity 1.5-2-fold, but GST activity was not induced by dietary BNF. Neither I3C nor I3N induced the activity levels of the enzymes assayed at any administered dietary levels, which have previously shown to inhibit tumor formation and reduce formation of carcinogen-DNA adducts. Thus, the anticarcinogenic mechanism of I3C may proceed in trout by mechanisms other than enzyme induction. Further experiments on the effect of I3C and I3C acid condensation products (RXN) on in vitro AFB1-DNA binding resulted in a 40% and 48% inhibition of AFB1-DNA binding by I3C and RXN, respectively. Additions of RXN at levels much lower than those estimated to exist in vivo in hepatic tissue resulted in a significant reduction in AFB1-DNA formation suggesting that even small levels of RXN offers protection against the genotoxic effect of AFB1. However, in vitro additions of neither I3C nor RXN had an effect on DNA binding using AFBI-CI₂, an aflatoxin analog that does not require enzymatic activation. These results suggest that the primary mechanism for I3C inhibition of AFB1 induced carcinogenesis may proceed by inhibiton of formation of the ultimate electrophile, i.e. by reversible inhibition of cytochrome P-450. / Graduation date: 1989

Nanotechnology is a rapidly growing industry of global economic importance, with new technologies exploiting the novel characteristics of materials manufactured at the nanoscale being developed for use within the biomedical, electronic, energy production and environmental sectors. The unusual properties of engineered nanomaterials (ENMs) that make them useful in such applications have led to concerns regarding their potential impact on the environment. The aquatic environment is particularly at risk of exposure to ENPs, yet, there is currently little known about their behaviour in aquatic systems, their capacity to be taken up by aquatic organisms or their potential toxic effects. The studies that were conducted during this work sought to investigate the ecotoxicology of a range of metal and metal oxide nanoparticles using fish as a vertebrate model. In order to gain a better understanding of the uptake and effects of ENMs in fish, rainbow trout (Oncorhynchus mykiss) were exposed to nanoparticulate (34 nm) and bulk (>100 nm) titanium dioxide particles via the water column (500 and 5000 µg L-1), and to titanium dioxide nanoparticles via the diet (0.1 and 1 mg g-1 food) and via intravenous injection (1.3 mg kg-1 body weight). Uptake of titanium dioxide into the tissues of trout after waterborne and dietary exposure was found to be very low, suggesting limited bioavailability of the nanoparticles to the fish, although small amounts of uptake of titanium dioxide across the gill epithelial membrane were observed using coherent anti-stokes Raman scattering. Intravenously injected titanium dioxide accumulated and was retained in the kidneys for up to 21 days, but no adverse effect on kidney function was detected. Silver nanoparticles are already in widespread use in a variety of consumer products such as wound dressings, food containers, sock fabrics and paints, principally for their antimicrobial activity. Despite its growing commercialisation, there is little known about the environmental effects of the use of nanoparticulate silver in these products. In order to investigate these potential effects, rainbow trout were also exposed to 10 nm, 35 nm and bulk (0.6-1.6 µm) silver particles via the water column at concentration of 10 and 100 µg L-1. Uptake of silver in the gills and liver of trout occurred, with smaller nanoparticles showing a greater propensity for association with gill tissue, but with no significant differences in uptake between particles of different sizes in the liver. No increases in lipid peroxidation were detected in gills, liver or blood plasma of trout, however, expression of cyp1a2 was significantly up-regulated in exposures to 10 nm silver particles in the gill, suggesting an increase in oxidative metabolism. In an attempt to develop an effective high through-put in vitro screening assay for ENMs, the suitability of isolated rainbow trout primary hepatocytes was examined as a potential model for in vitro screening of a range of toxicological endpoints in response to nanoparticles and for studying uptake of nanoparticles into cells. The hepatocytes retained a good level of functionality after culturing as evidenced by vitellogenin production in response to the synthetic oestrogen, 17β-oestradiol. The cultured hepatocytes, however, showed limited responses on exposure to titanium dioxide, zinc oxide, cerium oxide and silver nanoparticles for lipid peroxidation and glutathione-s-transferase activity assays. Furthermore, the hepatocytes were unresponsive to the induction of these biological responses in the positive controls, suggesting they are not a good model for investigating the potential toxic effects of ENMs in terms of these endpoints. Uptake of the nanoparticles into the cells, however, was demonstrated by coherent anti-stokes Raman spectroscopy, indicating that this in vitro assay may provide a useful model for studying uptake of ENPs into cells. The studies conducted in this thesis contribute the science base regarding the bioavailability of ENPs in aquatic media as well as highlighting the importance of characterisation of ENPs in understanding their behaviour, uptake and effects in aquatic systems and in fish.

The purpose of this thesis is to specifically address the religious dimensions of the Rainbow Gatherings. The fundamental question directing this analysis is: "Are the Rainbow Gatherings religious in character?" This thesis specifically asks whether or not the Rainbow Gatherings satisfy certain identifiable features of religion, and if doing so, do they qualify as a form of religion? I engage this question by analyzing the Rainbow Gatherings in terms of two particular definitions of religion: Clifford Geertz's "functional" definition and Bryan R. Wilson's "substantive" definition. This allows me to analyze the Rainbow Gatherings from the perspective of the two major approaches to defining religion. This thesis also explores the broader differences and implications of these two types of definitions in academia, as well as the significance this has for future studies of this sort. Conclusive results indicate that the Gatherings conform to both definitions in some ways, but not in others. The results also designate which of the two definitions the Gatherings satisfy more inclusively. Thus, this analysis not only examines whether or not these gatherings qualify as a form of religion, but also examines how these definitions of religion illuminate features of the Rainbow Gathering, and how this relates to the scholarly distinction of these two types of definitions.

This thesis tests the hypothesis that innate immunity may be enhanced immediately following a stressful event. The experiments characterize the acute effects of the fight or flight response on some immunological and endocrine parameters in rainbow trout (Oncorhynchus mykiss). Plasma cortisol and catecholamines were elevated within seconds of the initiation of an acute handling stressor consisting of 30 seconds in the air and five, 10 or 20 minutes in a shallow bucket of water. Plasma lysozyme activity increased after stress, however, the increases were not statistically significant unless variation was reduced by serial bleeding of the same individual trout before and after stress. A more "resting" fish was achieved by use of the anesthetic 2-phenoxy-ethanol which was surreptitiously introduced into the tanks before the initial bleed. Individual fish were then revived in freshwater and stressed as before. Enhancement of lysozyme activity was evident although levels of plasma stress hormones in fish that were anesthetized, revived and stressed were less than when fish were similarly stressed without anesthetic. Levels of cortisol and catecholamines increased within seconds of capture and aerial exposure, returned to near pre-stress levels after the fish had been placed in a shallow bucket of water for 30 seconds, then increased again. Evaluation of the influence of acute stress on survival following challenge with the pathogen Vibrio anguillarum yielded equivocal data. Results presented here suggest that enhancement of innate defenses as part of the fight or flight response merits further evaluation. / Graduation date: 1997

Graduation date: 1992

Rainbow trout were exposed to aluminum at pH 7.25 and 8.25 and four hardnesses (10, 30, 80, and 120 ppm CaCO₃) for 96 hours in a continuous-flow system and mortality and aluminum accumulation in the gills were determined. Temperature, pH, and dissolved oxygen were measured daily for each treatment. Dissolved and total aluminum concentrations and hardness were determined following exposure periods of 48 and 96 hours. Aluminum was most toxic at pH 8.25, and was more toxic at lower than at higher hardnesses. Water hardness provided a significant protective effect against aluminum-induced mortality (p < 0.05), and there were no significant effects for water hardness on gill accumulation at either of pH. At pH 7.25 no mortalities occurred under any conditions. At pH 8.25, the accumulation of aluminum in gill tissues was higher than for pH 7.25 following exposure for 96 hours. In addition, aluminum concentration and exposure time had a significantly cumulative effect on fish mortality (p < 0.05). Possible mechanisms for aluminum toxicity and the accumulation of aluminum in the gills of rainbow trout were attributed to the forms and solubilities of aluminum species at different pH values. Competition between Ca²⁺ and aluminum for binding sites on the gills likely influenced aluminum toxic action. / Graduation date: 1992

The peripheral-type benzodiazepine receptor (PTBR) of trout brain was pharmacologically characterized and pyrethroid interaction with this site investigated. High-affinity binding sites for [³H]PK 11195 were detected in brain membranes of rainbow trout; these shared some of the characteristics of the PTBR of rodent brain (i.e., high affinity for PK 11195 and an endogenous ligand protoporphyrin IX) but were unique in the low affinity for Ro5-4864. Permethrin displaced [³H]PK 11195 binding with micromolar affinity while deltamethrin had less than 50% efficacy at displacement. Thus the PTBR appeared not to be relevant to pyrethroid toxicity in rainbow trout. Pyrethroid interaction with the GABA, receptor was investigated using [³⁵S]TBPS as a radioligand probe and by measurement of GABA-stimulated ³⁶c1- influx in vesicle preparations. At micromolar concentrations, deltamethrin, cypermethrin isomers and other pyrethroids inhibited [³⁵S]TBPS binding by 55- 95% with limited stereoselectivity. Pyrethroids were found to effect a GABAdependent inhibition of [³⁵S]TBPS binding. Ro5-4864, which showed micromolar affinity for the trout PTBR, produced a GABA-modulated interaction with [³⁵S]TBPS binding. These results delineate the reciprocal allosteric interactions between a pyrethroid binding site, a Ro5-4864 binding site, the GABA recognition moiety and the TBPS binding site in trout brain. However, pyrethroids exhibited a modest affinity for this binding site on the GABAA receptor. Pyrethroids indirectly inhibited the GABA-dependent influx of ³⁶Cl⁻into trout brain synaptoneurosomes by increasing the basal uptake of chloride, thereby compromising the ability of the vesicles to respond to applications of GABA. This pyrethroid effect was of nanomolar potency, stereospecific, tetrodotoxinsensitive and mimicked by veratridine. These results suggest that the primary effect of pyrethroids in trout brain, as measured by this assay, was due to an interaction with voltage-dependent sodium channels, increasing sodium conductance and thereby increasing the basal uptake of ³⁶Cl⁻ through a voltagesensitive channel. The convulsant activity of deltamethrin was tested in rainbow trout. The EC₅₀ for convulsant severity was 32 μg /kg body weight. By comparison, pyrethroids at these concentrations in rodents produce no overt toxicity but act as potent proconvulsants. / Graduation date: 1990