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• 571. [Article] Lake classification in the glacially influenced landscape of the north Cascade mountains, Washington, USA

  Factors affecting physical, chemical, and biological characteristics of lakes were investigated through the development of a lake-classification system for 162 lakes in North Cascades National Park Service ...

  Citation × Citation Citation Abstract Copy Title: Lake classification in the glacially influenced landscape of the north Cascade mountains, Washington, USA Author: Lomnicky, Gregg A. Factors affecting physical, chemical, and biological characteristics of lakes were investigated through the development of a lake-classification system for 162 lakes in North Cascades National Park Service Complex. A conceptual view of lake development and its relationship to the expression of lake and watershed characteristics was derived. Water quality and biological assemblages of these primarily glacially formed high-mountain oligotrophic lakes were influenced by elevation, lake morphology, and certain watershed characteristics: aspect, vegetation, soils, hydrology, and degree of glacial influence. Lakes continually evolve relative to changes in their watershed environments. A watershed-based, three-level hierarchical classification was created to include 1) lake position relative to the hydrologic crest of the North Cascade Mountain Range, 2) vegetation zone (alpine, subalpine, low elevation forest, high elevation forest), and 3) basin origin. Hydrologic crest position differentiated broad-scale climatic differences in precipitation and air temperature. Vegetation zones reflected the localized geology (soil maturation) and climate (precipitation, aspect). Morphogenetic class identified differences in lake morphology, landscape position, and potential for persistence, and were unequally distributed across vegetation zones with forest zones most diverse. Time of ice-out increased from low-forest lakes to alpine lakes; eastslope lakes iced-out earlier. Epilimnetic temperature was warmest in low-forest lakes and coolest in alpine lakes. Classification did not clearly order lakes relative to chemical characteristics, though westslope low-forest lakes differed significantly from other lake classes and were most productive. Little seasonal or annual variation for most chemical characteristics were found. However, chemical differences did mirror environmental and physical differences between lakes. High phosphorus levels separated glacially influenced lakes. Total Kjeldahl-N and total phosphorus concentrations decreased with increasing lake depth. For a given flushing ratio, Kjeldahl-N decreased from low-forest to alpine zones. Depth and vegetation class ordered the diversity and composition of phytoplankton, zooplankton, and benthic macroinvertebrate assemblages. Nutrients, conductivity, pH, alkalinity, and cations were correlated with phytoplankton and zooplankton assemblages. Non-native trout presence was associated with large, deep [greater than or equal to] 3 m) lakes. Title: Lake classification in the glacially influenced landscape of the north Cascade mountains, Washington, USA Author: Lomnicky, Gregg A. Factors affecting physical, chemical, and biological characteristics of lakes were investigated through the development of a lake-classification system for 162 lakes in North Cascades National Park Service Complex. A conceptual view of lake development and its relationship to the expression of lake and watershed characteristics was derived. Water quality and biological assemblages of these primarily glacially formed high-mountain oligotrophic lakes were influenced by elevation, lake morphology, and certain watershed characteristics: aspect, vegetation, soils, hydrology, and degree of glacial influence. Lakes continually evolve relative to changes in their watershed environments. A watershed-based, three-level hierarchical classification was created to include 1) lake position relative to the hydrologic crest of the North Cascade Mountain Range, 2) vegetation zone (alpine, subalpine, low elevation forest, high elevation forest), and 3) basin origin. Hydrologic crest position differentiated broad-scale climatic differences in precipitation and air temperature. Vegetation zones reflected the localized geology (soil maturation) and climate (precipitation, aspect). Morphogenetic class identified differences in lake morphology, landscape position, and potential for persistence, and were unequally distributed across vegetation zones with forest zones most diverse. Time of ice-out increased from low-forest lakes to alpine lakes; eastslope lakes iced-out earlier. Epilimnetic temperature was warmest in low-forest lakes and coolest in alpine lakes. Classification did not clearly order lakes relative to chemical characteristics, though westslope low-forest lakes differed significantly from other lake classes and were most productive. Little seasonal or annual variation for most chemical characteristics were found. However, chemical differences did mirror environmental and physical differences between lakes. High phosphorus levels separated glacially influenced lakes. Total Kjeldahl-N and total phosphorus concentrations decreased with increasing lake depth. For a given flushing ratio, Kjeldahl-N decreased from low-forest to alpine zones. Depth and vegetation class ordered the diversity and composition of phytoplankton, zooplankton, and benthic macroinvertebrate assemblages. Nutrients, conductivity, pH, alkalinity, and cations were correlated with phytoplankton and zooplankton assemblages. Non-native trout presence was associated with large, deep [greater than or equal to] 3 m) lakes. Close

• 572. [Article] Isolation and characterization of a new reovirus from chum salmon (Oncorhynchus keta)

  This report describes the isolation of a new virus from adult chum salmon (Oncorhynchus keta) returning to the Tokushibetsu Hatchery, Hokkaido, Japan. The agent was isolated in the CHSE-214 cell line derived ...

  Citation × Citation Citation Abstract Copy Title: Isolation and characterization of a new reovirus from chum salmon (Oncorhynchus keta) Author: Winton, James R. This report describes the isolation of a new virus from adult chum salmon (Oncorhynchus keta) returning to the Tokushibetsu Hatchery, Hokkaido, Japan. The agent was isolated in the CHSE-214 cell line derived from chinook salmon (Oncorhynchus tshawytscha). The virus replicated in selected fish cell lines incubated between 10 and 20°C and produced a unique cytopathic effect characterized by the formation of circular plaque-like areas of cytoplasmic fusion. The nuclei of the cells were not affected. Physical and chemical studies have shown the agent, tentatively named chum salmon virus, to be a member of the family Reoviridae and distinct from any known virus of fish. Electron microscopy of negatively stained particles revealed a naked icosahedral virion 75 nm in diameter with a clearly defined double capsid. Treatment with α-chymotrypsin removed the outer capsid yielding 50-55 nm subviral particles with enhanced infectivity. Viral infectivity was not reduced by treatment with ether or chloroform. The virus was resistant to freeze-thaw and pH 3, but unstable at 56°C. It did not hemagglutinate human type 0 erythrocytes. No cross-neutralization was observed with antiserum against reovirus types 1, 2 or 3 or against infectious pancreatic necrosis virus. Viral replication was not inhibited by 5-fluoro-2'-deoxyuridine and infected cells stained with acridine orange showed typical reoviruslike cytoplasmic inclusions. Polyacrylamide gel electrophoresis of the viral genome revealed 10 segments of double-stranded RNA ranging in weight from 2.6 X 10⁶ to 0.32 X 10⁶ daltons with a total genome weight of 15.3 X 10⁶ daltons. Analysis of virion polypeptides on SDSpolyacrylamide gels indicated five major virion proteins with molecular weights of 145,000, 130,000, 75,000, 43,000 and 33,000 daltons were present in the intact virion. Two minor polypeptides of 80,000 and 30,000 daltons were also present. The density of the intact virion in CsC1 was 1.33 g/cc. The virus had limited pathogenicity for salmonid fish. Chum and chinook salmon infected with the virus exhibited a focal necrotizing hepatitis. No mortality could be attributed to these lesions which were active sites of viral synthesis. Rainbow trout (Salmo gairdneri) and kokanee salmon (Oncorhynchus nerka) showed no pathological changes in any organ system examined. The virus replicated in all four species tested. Title: Isolation and characterization of a new reovirus from chum salmon (Oncorhynchus keta) Author: Winton, James R. This report describes the isolation of a new virus from adult chum salmon (Oncorhynchus keta) returning to the Tokushibetsu Hatchery, Hokkaido, Japan. The agent was isolated in the CHSE-214 cell line derived from chinook salmon (Oncorhynchus tshawytscha). The virus replicated in selected fish cell lines incubated between 10 and 20°C and produced a unique cytopathic effect characterized by the formation of circular plaque-like areas of cytoplasmic fusion. The nuclei of the cells were not affected. Physical and chemical studies have shown the agent, tentatively named chum salmon virus, to be a member of the family Reoviridae and distinct from any known virus of fish. Electron microscopy of negatively stained particles revealed a naked icosahedral virion 75 nm in diameter with a clearly defined double capsid. Treatment with α-chymotrypsin removed the outer capsid yielding 50-55 nm subviral particles with enhanced infectivity. Viral infectivity was not reduced by treatment with ether or chloroform. The virus was resistant to freeze-thaw and pH 3, but unstable at 56°C. It did not hemagglutinate human type 0 erythrocytes. No cross-neutralization was observed with antiserum against reovirus types 1, 2 or 3 or against infectious pancreatic necrosis virus. Viral replication was not inhibited by 5-fluoro-2'-deoxyuridine and infected cells stained with acridine orange showed typical reoviruslike cytoplasmic inclusions. Polyacrylamide gel electrophoresis of the viral genome revealed 10 segments of double-stranded RNA ranging in weight from 2.6 X 10⁶ to 0.32 X 10⁶ daltons with a total genome weight of 15.3 X 10⁶ daltons. Analysis of virion polypeptides on SDSpolyacrylamide gels indicated five major virion proteins with molecular weights of 145,000, 130,000, 75,000, 43,000 and 33,000 daltons were present in the intact virion. Two minor polypeptides of 80,000 and 30,000 daltons were also present. The density of the intact virion in CsC1 was 1.33 g/cc. The virus had limited pathogenicity for salmonid fish. Chum and chinook salmon infected with the virus exhibited a focal necrotizing hepatitis. No mortality could be attributed to these lesions which were active sites of viral synthesis. Rainbow trout (Salmo gairdneri) and kokanee salmon (Oncorhynchus nerka) showed no pathological changes in any organ system examined. The virus replicated in all four species tested. Close

• 573. [Article] Absorbed dose from X rays in soft tissue adjacent to bone measured by induced conductivity in polyethylene films

  The X-ray dose absorbed in soft tissue located near plane bone interfaces and in parallel-slab bone cavities was measured experimentally with a polyethylene-film dosimeter. The dose absorbed in soft tissue ...

  Citation × Citation Citation Abstract Copy Title: Absorbed dose from X rays in soft tissue adjacent to bone measured by induced conductivity in polyethylene films Author: Lentsch, Jack Wayne The X-ray dose absorbed in soft tissue located near plane bone interfaces and in parallel-slab bone cavities was measured experimentally with a polyethylene-film dosimeter. The dose absorbed in soft tissue adjacent to plane bone interfaces was measured by placing a 12.7 micron film of polyethylene, upon which were deposited graphite electrodes, in contact with bone-equivalent disks of Shonka plastic. The dose was measured both as a function of X-ray quality and distance of the tissue-equivalent polyethylene away from the bone interface. The dose in finite soft tissue layers next to bone was also measured as a function of X-ray quality. The results indicated that the soft tissue dose in finite layers next to the bone was greater than that remote from the bone. At the lower effective X-ray energies the dose very close to the bone was considerably higher than for the higher effective X-ray energies. At higher effective X-ray energies, however, the increased dose effect extended to a greater depth in the soft tissue. At effective energies greater than 177 keV electronic equilibrium was obtained, and the dose was the same for the adjacent and distant soft tissue. Comparisons were made of the experimentally measured doses in soft tissue near plane bone interfaces with calculated doses for monoenergetic photons. It was observed that at effective X-ray energies below approximately 60 keV the experimental results gave higher dose values than the theoretical values. However, at higher effective X-ray energies there was good agreement between the experimental and theoretical results. It was concluded that X-ray spectral considerations were mainly responsible for the deviations at lower effective energies. The results of this study indicated that when one wishes to calculate the dose absorbed in soft tissue adjacent to plane bone interfaces at low effective X-ray energies, the theory cannot be relied upon and experimentally determined doses such as those shown herein should be used instead. The X-ray dose in soft tissue elements interposed between parallel slabs of bone was measured in the same manner as the dose in soft tissue adjacent to plane bone interfaces. However, due to experimental difficulties in simulating this bone-tissue orientation, it was not possible to make reasonable dose measurements. Title: Absorbed dose from X rays in soft tissue adjacent to bone measured by induced conductivity in polyethylene films Author: Lentsch, Jack Wayne The X-ray dose absorbed in soft tissue located near plane bone interfaces and in parallel-slab bone cavities was measured experimentally with a polyethylene-film dosimeter. The dose absorbed in soft tissue adjacent to plane bone interfaces was measured by placing a 12.7 micron film of polyethylene, upon which were deposited graphite electrodes, in contact with bone-equivalent disks of Shonka plastic. The dose was measured both as a function of X-ray quality and distance of the tissue-equivalent polyethylene away from the bone interface. The dose in finite soft tissue layers next to bone was also measured as a function of X-ray quality. The results indicated that the soft tissue dose in finite layers next to the bone was greater than that remote from the bone. At the lower effective X-ray energies the dose very close to the bone was considerably higher than for the higher effective X-ray energies. At higher effective X-ray energies, however, the increased dose effect extended to a greater depth in the soft tissue. At effective energies greater than 177 keV electronic equilibrium was obtained, and the dose was the same for the adjacent and distant soft tissue. Comparisons were made of the experimentally measured doses in soft tissue near plane bone interfaces with calculated doses for monoenergetic photons. It was observed that at effective X-ray energies below approximately 60 keV the experimental results gave higher dose values than the theoretical values. However, at higher effective X-ray energies there was good agreement between the experimental and theoretical results. It was concluded that X-ray spectral considerations were mainly responsible for the deviations at lower effective energies. The results of this study indicated that when one wishes to calculate the dose absorbed in soft tissue adjacent to plane bone interfaces at low effective X-ray energies, the theory cannot be relied upon and experimentally determined doses such as those shown herein should be used instead. The X-ray dose in soft tissue elements interposed between parallel slabs of bone was measured in the same manner as the dose in soft tissue adjacent to plane bone interfaces. However, due to experimental difficulties in simulating this bone-tissue orientation, it was not possible to make reasonable dose measurements. Close

• 574. [Article] BOD and toxicity of log leachates

  A series of log storage experiments were conducted to determine whether leachates derived from water storage of logs are acutely toxic to fish. Log segments approximately 18 inches long and 16 inches in ...

  Citation × Citation Citation Abstract Copy Title: BOD and toxicity of log leachates Author: Atkinson, Sheridan William A series of log storage experiments were conducted to determine whether leachates derived from water storage of logs are acutely toxic to fish. Log segments approximately 18 inches long and 16 inches in diameter were stored in tanks and held submerged for a period of 7 days. The holding water containing leached materials was made toxic with mercury to retard biological decomposition of the leached substances. Mercury was selectively removed from leachate samples by chelation prior to biochemical oxygen demand (BOD) and bioassay testing. Trout and salmon fry were subjected to the leachate water in short term acute bioassay tests. Results are reported as a median tolerance limit, (TLm), i. e., the concentration of leachate at which 50 percent of the test fish died for any given exposure time. Leachates were also tested for BOD₅, BOD k-rate, chemical oxygen demand (COD), wood sugar and Pearl Benson Index (PBI). Test results show that leachates from Douglas fir stored in fresh water exert a slight acute toxicity to fish. A TLm₉₆ of 20 percent leachate by volume, for a 50 year old Douglas fir log, was the most toxic leachate observed. Leachates from ponderosa pine, hemlock and an older fir log stored under identical conditions produced no measurable acute toxicity. Leachates contained a significant quantity of BOD and PBI exerting substances. The highest BOD₅, (1.36 g/ft² of submerged surface area) was exerted by leachate from a ponderosa pine log segment stored with bark removed. The highest PBI valve (12.5 g/ft²), was observed for leachate from a young Douglas fir log segment. BOD:COD ratios and BOD k-rate ranged widely for the various leachates, but were relatively low which indicated a significant fraction of non-biodegradable substances. Hoffbuhr (9) also observed a high non-biodegradable fraction in samples taken from log storage ponds. Wood sugars were found to account for a large part of the degradable portion of leachates. Leachate from ponderosa pine log with bark intact exerted a high BOD and also contained the highest concentration of wood sugar observed, 0.84 g/ft². Title: BOD and toxicity of log leachates Author: Atkinson, Sheridan William A series of log storage experiments were conducted to determine whether leachates derived from water storage of logs are acutely toxic to fish. Log segments approximately 18 inches long and 16 inches in diameter were stored in tanks and held submerged for a period of 7 days. The holding water containing leached materials was made toxic with mercury to retard biological decomposition of the leached substances. Mercury was selectively removed from leachate samples by chelation prior to biochemical oxygen demand (BOD) and bioassay testing. Trout and salmon fry were subjected to the leachate water in short term acute bioassay tests. Results are reported as a median tolerance limit, (TLm), i. e., the concentration of leachate at which 50 percent of the test fish died for any given exposure time. Leachates were also tested for BOD₅, BOD k-rate, chemical oxygen demand (COD), wood sugar and Pearl Benson Index (PBI). Test results show that leachates from Douglas fir stored in fresh water exert a slight acute toxicity to fish. A TLm₉₆ of 20 percent leachate by volume, for a 50 year old Douglas fir log, was the most toxic leachate observed. Leachates from ponderosa pine, hemlock and an older fir log stored under identical conditions produced no measurable acute toxicity. Leachates contained a significant quantity of BOD and PBI exerting substances. The highest BOD₅, (1.36 g/ft² of submerged surface area) was exerted by leachate from a ponderosa pine log segment stored with bark removed. The highest PBI valve (12.5 g/ft²), was observed for leachate from a young Douglas fir log segment. BOD:COD ratios and BOD k-rate ranged widely for the various leachates, but were relatively low which indicated a significant fraction of non-biodegradable substances. Hoffbuhr (9) also observed a high non-biodegradable fraction in samples taken from log storage ponds. Wood sugars were found to account for a large part of the degradable portion of leachates. Leachate from ponderosa pine log with bark intact exerted a high BOD and also contained the highest concentration of wood sugar observed, 0.84 g/ft². Close

• 575. [Article] Heterogeneous thermal habitat for northeast Oregon stream fishes

  Discrete coldwater patches within warm streams provide potential thermal refuge for coldwater fishes during periods of heat stress. This analysis focused on heterogeneity in stream water temperatures as ...

  Citation × Citation Citation Abstract Copy Title: Heterogeneous thermal habitat for northeast Oregon stream fishes Author: Ebersole, Joseph L. Discrete coldwater patches within warm streams provide potential thermal refuge for coldwater fishes during periods of heat stress. This analysis focused on heterogeneity in stream water temperatures as influenced by local influx of cooler subsurface waters. Using field thermal probes and recording thermistors, we identified and characterized coldwater patches potentially serving as thermal refugia for coldwater fishes. Coldwater patches within the surface waters of summer-warm streams generally occurred along the stream channel margin and were classified into four morphological types. Isolation, measured as distance of the coldwater patch from the main channel, was related to the composition of fish assemblages occurring within coldwater patches. Assemblages dominated by catostomids used coldwater patches furthest from the main channel, while salmonids utilized coldwater patches closer to the main channel. Increased isolation of coldwater patches from the main channel was hypothesized to incur greater risks of predation and greater energetic demands on fishes moving between coldwater patches and the main channel. Coldwater patch isolation distance increased in stream channels that were wider and shallower, and riparian canopy density over coldwater patches decreased with increasing channel width:depth. Strong vertical gradients in temperature associated with heating of surface layers of coldwater patches exposed to solar radiation superimposed upon vertical gradients in dissolved oxygen may restrict suitable refuge volumes for stream salmonids within coldwater patches. These relationships suggest that stream channel and riparian characteristics may influence connectivity and suitability of coldwater patches for stream fishes. Coldwater patch availability (measured as frequency and relative area) was positively associated with higher abundances of rainbow trout within stream reaches, after accounting for other habitat characteristics influencing abundance. Chinook salmon abundance was positively associated with coldwater patch frequency, but was not associated with coldwater patch area within streams. These results suggest that the physiognomy, distribution and connectivity of coldwater patches, important attributes determining the effectiveness of these habitats as thermal refugia for stream fishes, are associated with reach-level channel bedform and riparian features. We propose that patterns of thermal heterogeneity associated with channel morphology may provide an important aspect of habitat structure for stream fishes. Title: Heterogeneous thermal habitat for northeast Oregon stream fishes Author: Ebersole, Joseph L. Discrete coldwater patches within warm streams provide potential thermal refuge for coldwater fishes during periods of heat stress. This analysis focused on heterogeneity in stream water temperatures as influenced by local influx of cooler subsurface waters. Using field thermal probes and recording thermistors, we identified and characterized coldwater patches potentially serving as thermal refugia for coldwater fishes. Coldwater patches within the surface waters of summer-warm streams generally occurred along the stream channel margin and were classified into four morphological types. Isolation, measured as distance of the coldwater patch from the main channel, was related to the composition of fish assemblages occurring within coldwater patches. Assemblages dominated by catostomids used coldwater patches furthest from the main channel, while salmonids utilized coldwater patches closer to the main channel. Increased isolation of coldwater patches from the main channel was hypothesized to incur greater risks of predation and greater energetic demands on fishes moving between coldwater patches and the main channel. Coldwater patch isolation distance increased in stream channels that were wider and shallower, and riparian canopy density over coldwater patches decreased with increasing channel width:depth. Strong vertical gradients in temperature associated with heating of surface layers of coldwater patches exposed to solar radiation superimposed upon vertical gradients in dissolved oxygen may restrict suitable refuge volumes for stream salmonids within coldwater patches. These relationships suggest that stream channel and riparian characteristics may influence connectivity and suitability of coldwater patches for stream fishes. Coldwater patch availability (measured as frequency and relative area) was positively associated with higher abundances of rainbow trout within stream reaches, after accounting for other habitat characteristics influencing abundance. Chinook salmon abundance was positively associated with coldwater patch frequency, but was not associated with coldwater patch area within streams. These results suggest that the physiognomy, distribution and connectivity of coldwater patches, important attributes determining the effectiveness of these habitats as thermal refugia for stream fishes, are associated with reach-level channel bedform and riparian features. We propose that patterns of thermal heterogeneity associated with channel morphology may provide an important aspect of habitat structure for stream fishes. Close

• 576. [Article] Evaluation of zebrafish (Brachydanio rerio) as a model for carcinogenesis

  Zebrafish (Brachydanio rerio) are small, freshwater teleost fishes in the family Cyprinidae, the true minnows. They are native to the tropical latitudes of India, but have become widespread through their ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of zebrafish (Brachydanio rerio) as a model for carcinogenesis Author: Tsai, Hsi-Wen Zebrafish (Brachydanio rerio) are small, freshwater teleost fishes in the family Cyprinidae, the true minnows. They are native to the tropical latitudes of India, but have become widespread through their use as aquarium fish and as models for several branches of biological research. Their ease of rearing, short generation time, year-around egg laying potential, brief developmental period, and embryo transparency have made them especially desirable as models for developmental biology, genetics, and neurobiology. Because of their popularity, they were also the first small aquarium fish to be used as test organisms for carcinogenesis in the early 1960's. For reasons that have never been stated, their use as a model for carcinogenesis research did not continue. Due to the number of positive characteristics that this species has, the goal of this research effort was to systematically evaluate the potential of zebrafish for use as an environmental monitor, to evaluate the toxicology and carcinogenesis of surface and/or ground waters. The overall project was multidisciplinary in nature, but the focus of this thesis research was on the whole animal, dose-response to a number of well-known carcinogens, administered by multiple exposure routes, and the pathological description of the resulting lesions. Exposure to N-nitrosodiethylamine (DEN) and N-nitrosodimethylamine (DMN) in the diet was ineffective, but static water bath exposure of fry and embryos to these nitrosamines resulted in neoplasms, primarily in the liver. Embryo exposure to DEN resulted in a low response of neoplasms in several other organs as well. Dietary exposure of zebrafish to aflatoxin B₁ resulted in few hepatic neoplasms, revealing a marked resistance to this carcinogen. Dietary exposure to methylazoxymethanol acetate (MAM-Ac) produced mostly liver tumors, as did both fry and embryo water bath exposures. Each water bath exposure also produced neoplasms at other tissue and organ sites, but the embryo stage produced the greatest variety. These results demonstrate a relative resistance to neoplastic development compared to the well-known rainbow trout model. But in one comparative trial, zebrafish were similar to Japanese medaka in their response to dietary MAM-Ac. The major limitation of this species, that will prevent its use as a model for environmental monitoring, however, is its narrow range of temperature tolerance. Temperatures below 15°C produce marked sluggishness, and below 10-12°C cause anesthesia and death. Therefore, this research indicates that this species is not as versatile as some other small fish species for laboratory and especially field monitoring of environmental carcinogenic hazards. Title: Evaluation of zebrafish (Brachydanio rerio) as a model for carcinogenesis Author: Tsai, Hsi-Wen Zebrafish (Brachydanio rerio) are small, freshwater teleost fishes in the family Cyprinidae, the true minnows. They are native to the tropical latitudes of India, but have become widespread through their use as aquarium fish and as models for several branches of biological research. Their ease of rearing, short generation time, year-around egg laying potential, brief developmental period, and embryo transparency have made them especially desirable as models for developmental biology, genetics, and neurobiology. Because of their popularity, they were also the first small aquarium fish to be used as test organisms for carcinogenesis in the early 1960's. For reasons that have never been stated, their use as a model for carcinogenesis research did not continue. Due to the number of positive characteristics that this species has, the goal of this research effort was to systematically evaluate the potential of zebrafish for use as an environmental monitor, to evaluate the toxicology and carcinogenesis of surface and/or ground waters. The overall project was multidisciplinary in nature, but the focus of this thesis research was on the whole animal, dose-response to a number of well-known carcinogens, administered by multiple exposure routes, and the pathological description of the resulting lesions. Exposure to N-nitrosodiethylamine (DEN) and N-nitrosodimethylamine (DMN) in the diet was ineffective, but static water bath exposure of fry and embryos to these nitrosamines resulted in neoplasms, primarily in the liver. Embryo exposure to DEN resulted in a low response of neoplasms in several other organs as well. Dietary exposure of zebrafish to aflatoxin B₁ resulted in few hepatic neoplasms, revealing a marked resistance to this carcinogen. Dietary exposure to methylazoxymethanol acetate (MAM-Ac) produced mostly liver tumors, as did both fry and embryo water bath exposures. Each water bath exposure also produced neoplasms at other tissue and organ sites, but the embryo stage produced the greatest variety. These results demonstrate a relative resistance to neoplastic development compared to the well-known rainbow trout model. But in one comparative trial, zebrafish were similar to Japanese medaka in their response to dietary MAM-Ac. The major limitation of this species, that will prevent its use as a model for environmental monitoring, however, is its narrow range of temperature tolerance. Temperatures below 15°C produce marked sluggishness, and below 10-12°C cause anesthesia and death. Therefore, this research indicates that this species is not as versatile as some other small fish species for laboratory and especially field monitoring of environmental carcinogenic hazards. Close

• 577. [Article] Assessment of the quantitative fluorescent antibody technique and chemotherapy for the detection and control of Renibacterium salmoninarum in salmonid fishes

  Detection and treatment of bacterial kidney disease (BKD) was investigated. Experiments were conducted to evaluate the quantitative, fluorescent antibody technique (QFAT) that is used to detect, identify, ...

  Citation × Citation Citation Abstract Copy Title: Assessment of the quantitative fluorescent antibody technique and chemotherapy for the detection and control of Renibacterium salmoninarum in salmonid fishes Author: Drongesen, Jeffrey Edward Detection and treatment of bacterial kidney disease (BKD) was investigated. Experiments were conducted to evaluate the quantitative, fluorescent antibody technique (QFAT) that is used to detect, identify, and quantify both typical and 'bar form' Renibacterium salmoninarum cells. Smears of kidney tissue from naturally and artificially infected salmonids, both with and without chemotherapy, were quantitatively examined throughout the course of R. salmoninarum infections. Detection and quantification by QFAT has been reported to provide assessments of prevalence and severity of R. salmoninarum of individual fish. These assessments and the occurrence of 'bar forms' of R. salmoninarum have been used as an indication of recovery within a population. 'Bar forms' were observed in kidney tissue smears of fish that survived bacterial challenge when treated with erythromycin. The 'bar form' was also detected when rainbow trout were artificially infected with lower doses of live R . salmoninarum and in fish that were injected with irradiation-inactivated R. salmoninarum cells. By examining R. salmoninarum cultures in vitro by QFAT, it was determined that 'bar forms' did not occur on artificial media even when antibiotics were incorporated into the agar. When QFAT was compared to direct fluorescent antibody technique (DFAT) and quantitative enzyme linked immunosorbent assay (ELISA), it was determined that QFAT had similar sensitivity as ELISA but was more sensitive than DFAT. QFAT was also used to predict minimum mortality. Experiments were also conducted to evaluate drug regimes to treat both artificial and natural R. salmoninarum infections. Erythromycin was administered by intraperitoneal injection in different doses and at selected days post infection. Erythromycin decreased percent mortality and increased mean day to death, but did not completely eradicate R. salmoninarum from infected test animals. Sarafloxacin and erythromycin were incorporated into daily ration of artificially infected test animals. Contrary to erythromycin, sarafloxacin did not decrease mortality or increase mean day to death when tested in vivo against R. salmoninarum. A new drug, A-77143, was tested in vitro to determine if it was bactericidal and its minimum inhibitory concentration. When A- 77143 was compared to other antibiotics, it had a relatively low minimum inhibitory concentration and was shown to be bactericidal against the eight strains of R. salmoninarum tested. Title: Assessment of the quantitative fluorescent antibody technique and chemotherapy for the detection and control of Renibacterium salmoninarum in salmonid fishes Author: Drongesen, Jeffrey Edward Detection and treatment of bacterial kidney disease (BKD) was investigated. Experiments were conducted to evaluate the quantitative, fluorescent antibody technique (QFAT) that is used to detect, identify, and quantify both typical and 'bar form' Renibacterium salmoninarum cells. Smears of kidney tissue from naturally and artificially infected salmonids, both with and without chemotherapy, were quantitatively examined throughout the course of R. salmoninarum infections. Detection and quantification by QFAT has been reported to provide assessments of prevalence and severity of R. salmoninarum of individual fish. These assessments and the occurrence of 'bar forms' of R. salmoninarum have been used as an indication of recovery within a population. 'Bar forms' were observed in kidney tissue smears of fish that survived bacterial challenge when treated with erythromycin. The 'bar form' was also detected when rainbow trout were artificially infected with lower doses of live R . salmoninarum and in fish that were injected with irradiation-inactivated R. salmoninarum cells. By examining R. salmoninarum cultures in vitro by QFAT, it was determined that 'bar forms' did not occur on artificial media even when antibiotics were incorporated into the agar. When QFAT was compared to direct fluorescent antibody technique (DFAT) and quantitative enzyme linked immunosorbent assay (ELISA), it was determined that QFAT had similar sensitivity as ELISA but was more sensitive than DFAT. QFAT was also used to predict minimum mortality. Experiments were also conducted to evaluate drug regimes to treat both artificial and natural R. salmoninarum infections. Erythromycin was administered by intraperitoneal injection in different doses and at selected days post infection. Erythromycin decreased percent mortality and increased mean day to death, but did not completely eradicate R. salmoninarum from infected test animals. Sarafloxacin and erythromycin were incorporated into daily ration of artificially infected test animals. Contrary to erythromycin, sarafloxacin did not decrease mortality or increase mean day to death when tested in vivo against R. salmoninarum. A new drug, A-77143, was tested in vitro to determine if it was bactericidal and its minimum inhibitory concentration. When A- 77143 was compared to other antibiotics, it had a relatively low minimum inhibitory concentration and was shown to be bactericidal against the eight strains of R. salmoninarum tested. Close

• 578. [Article] Effects of stream restoration on macroinvertebrate communities in an Oregon Coast Range system

  Stream-restoration projects are usually designed to improve habitat quality for fishes. These projects manipulate flow patterns, substrate distribution, and amount and placement of large woody debris. ...

  Citation × Citation Citation Abstract Copy Title: Effects of stream restoration on macroinvertebrate communities in an Oregon Coast Range system Author: Christensen, M. Jo Stream-restoration projects are usually designed to improve habitat quality for fishes. These projects manipulate flow patterns, substrate distribution, and amount and placement of large woody debris. Consequently, they also affect the size and composition of the aquatic macroinvertebrate community. This research evaluates two types of fish habitat restoration: off-channel structures (alcoves) and in-channel structures (log weirs). I compared macroinvertebrate habitats and communities in natural and artificial alcoves in Upper and South Fork Lobster Creeks, Lane Co., and examined the effects of log weirs on in-channel habitat diversity, community composition, drift patterns, and fish consumption of macroinvertebrates. Macroinvertebrate samples were collected from artificial and natural alcoves using hand pumps and D-nets. Within the channel, macroinvertebrates were collected from restored and unrestored reaches with a Hess sampler and using a stratified random sampling scheme. Forty-eight hour invertebrate drift samples were obtained at outlets of log-weir pools. Stomach contents were obtained from coho salmon (Oncorhynchus kisutch) and cutthroat trout (O. clarki) in restored reaches. Although natural alcoves differed from artificial in location within the floodplain, morphology, permanence, and degree of interaction with the stream channel, both alcovetypes provided similar habitats and contained similar macroinvertebrate communities. Average densities and diversity within the alcoves depended on habitat and time of year. Average densities were higher in artificial than in natural. Alcoves contained 29% of species richness within Upper Lobster Creek. Within the stream channel, the diversity of macroinvertebrate habitat was lower in restored than in unrestored sections. Log weirs were associated with reduced taxonomic and functional feeding-group diversity. Composition of drift was not significantly different in restored and unrestored areas; however, drift densities were significantly lower in restored reaches. Diets of fishes in restored areas were composed primarily of organisms produced from outside restored areas. Although in-channel structures may enhance physical habitat for fishes, they may alter or reduce the availability of food for fishes feeding on drifting invertebrates. Recommendations are given for improving the design of stream restoration projects with respect to macroinvertebrates; however stream restoration should focus on restoring whole-system integrity and function, instead of targeting just one or two types of organisms. Title: Effects of stream restoration on macroinvertebrate communities in an Oregon Coast Range system Author: Christensen, M. Jo Stream-restoration projects are usually designed to improve habitat quality for fishes. These projects manipulate flow patterns, substrate distribution, and amount and placement of large woody debris. Consequently, they also affect the size and composition of the aquatic macroinvertebrate community. This research evaluates two types of fish habitat restoration: off-channel structures (alcoves) and in-channel structures (log weirs). I compared macroinvertebrate habitats and communities in natural and artificial alcoves in Upper and South Fork Lobster Creeks, Lane Co., and examined the effects of log weirs on in-channel habitat diversity, community composition, drift patterns, and fish consumption of macroinvertebrates. Macroinvertebrate samples were collected from artificial and natural alcoves using hand pumps and D-nets. Within the channel, macroinvertebrates were collected from restored and unrestored reaches with a Hess sampler and using a stratified random sampling scheme. Forty-eight hour invertebrate drift samples were obtained at outlets of log-weir pools. Stomach contents were obtained from coho salmon (Oncorhynchus kisutch) and cutthroat trout (O. clarki) in restored reaches. Although natural alcoves differed from artificial in location within the floodplain, morphology, permanence, and degree of interaction with the stream channel, both alcovetypes provided similar habitats and contained similar macroinvertebrate communities. Average densities and diversity within the alcoves depended on habitat and time of year. Average densities were higher in artificial than in natural. Alcoves contained 29% of species richness within Upper Lobster Creek. Within the stream channel, the diversity of macroinvertebrate habitat was lower in restored than in unrestored sections. Log weirs were associated with reduced taxonomic and functional feeding-group diversity. Composition of drift was not significantly different in restored and unrestored areas; however, drift densities were significantly lower in restored reaches. Diets of fishes in restored areas were composed primarily of organisms produced from outside restored areas. Although in-channel structures may enhance physical habitat for fishes, they may alter or reduce the availability of food for fishes feeding on drifting invertebrates. Recommendations are given for improving the design of stream restoration projects with respect to macroinvertebrates; however stream restoration should focus on restoring whole-system integrity and function, instead of targeting just one or two types of organisms. Close

• 579. [Article] Studies on some digenetic trematodes from Ritner Creek, Polk County, Oregon

  Seven species of fresh water fishes belonging to three different families and two species of snails from Ritner Creek, Polk County, Oregon were surveyed for adult and larval trematodes. A total of seven ...

  Citation × Citation Citation Abstract Copy Title: Studies on some digenetic trematodes from Ritner Creek, Polk County, Oregon Author: Law, Daniel Tin-Hung Seven species of fresh water fishes belonging to three different families and two species of snails from Ritner Creek, Polk County, Oregon were surveyed for adult and larval trematodes. A total of seven species of trematodes representing four families was recovered from the intestine of the fishes. Of these, at least two were under scribed new species. The trematodes were described and their taxonomy discussed. The stream snails, Oxytrema silicula and Flumenicola virens, were found to harbor at least 17 apparent species of larval trematodes. Five of these were described from the snails for the first time. A check-list of cercariae known to infect O. silicula and F. virens in the Pacific Northwest was presented. Life histories of five of the trematodes .encountered during the surveys were studied. The experimental life cycle of Apophallus donicus Skrjabin and Lindtrop, 1919 was completed. The cercaria, of the pleurolophocercous group, was found in F. virens, while the metacercaria encysted in a number of fresh water fishes. The life cycle of Plagioporus siliculus Sinitsin, 1931 was demonstrated for the first time. The cotylomicrocercous cercaria developed in sporocyst in O. silicula and penetrated crayfish, Pacifastacus lenuisculus to encyst in the abdominal muscles. The experimental definitive host used was the rainbow trout. A single adult Echinochasmus milvi Yamaguti, 1939 was recovered from a duck fed echinostome cysts found naturally in the gills of blackside dace, Rhinichthys osculus nubilus and redside shiner, Richardsoni balteatus hydrophlox. This constituted the third record of the trematode in the Pacific Northwest. The cercaria of E. milvi was believed to be Cercaria gorgonocephala Ward, 1916, which Martin (1968) redescribed from O. silicula. Two other macrocercous cercariae--one aggregating but albino while the other nonaggregating-- were also found in O. silicula, The body of these cercariae was identical to that of C. gorgonocephala. The taxonomic relation of the three cercariae was discussed. The partial life cycle of a new monorchiid trematode from the torrent sculpin, Cottus rhotheus, was presented. The natural secondary intermediate host was found to be lampreys, both brook (Lampetra richardsoni) and Pacific (L. tridentata). The first intermediate host is still unknown. The partial life cycle of another new trematode, an Echinochasmus sp., was also reported. The adult was obtained from a duck experimentally fed small cysts in the gills of blackside dace. The first intermediate host is unknown. Title: Studies on some digenetic trematodes from Ritner Creek, Polk County, Oregon Author: Law, Daniel Tin-Hung Seven species of fresh water fishes belonging to three different families and two species of snails from Ritner Creek, Polk County, Oregon were surveyed for adult and larval trematodes. A total of seven species of trematodes representing four families was recovered from the intestine of the fishes. Of these, at least two were under scribed new species. The trematodes were described and their taxonomy discussed. The stream snails, Oxytrema silicula and Flumenicola virens, were found to harbor at least 17 apparent species of larval trematodes. Five of these were described from the snails for the first time. A check-list of cercariae known to infect O. silicula and F. virens in the Pacific Northwest was presented. Life histories of five of the trematodes .encountered during the surveys were studied. The experimental life cycle of Apophallus donicus Skrjabin and Lindtrop, 1919 was completed. The cercaria, of the pleurolophocercous group, was found in F. virens, while the metacercaria encysted in a number of fresh water fishes. The life cycle of Plagioporus siliculus Sinitsin, 1931 was demonstrated for the first time. The cotylomicrocercous cercaria developed in sporocyst in O. silicula and penetrated crayfish, Pacifastacus lenuisculus to encyst in the abdominal muscles. The experimental definitive host used was the rainbow trout. A single adult Echinochasmus milvi Yamaguti, 1939 was recovered from a duck fed echinostome cysts found naturally in the gills of blackside dace, Rhinichthys osculus nubilus and redside shiner, Richardsoni balteatus hydrophlox. This constituted the third record of the trematode in the Pacific Northwest. The cercaria of E. milvi was believed to be Cercaria gorgonocephala Ward, 1916, which Martin (1968) redescribed from O. silicula. Two other macrocercous cercariae--one aggregating but albino while the other nonaggregating-- were also found in O. silicula, The body of these cercariae was identical to that of C. gorgonocephala. The taxonomic relation of the three cercariae was discussed. The partial life cycle of a new monorchiid trematode from the torrent sculpin, Cottus rhotheus, was presented. The natural secondary intermediate host was found to be lampreys, both brook (Lampetra richardsoni) and Pacific (L. tridentata). The first intermediate host is still unknown. The partial life cycle of another new trematode, an Echinochasmus sp., was also reported. The adult was obtained from a duck experimentally fed small cysts in the gills of blackside dace. The first intermediate host is unknown. Close

• 580. [Article] Self actualization of students participating in the junior block teacher education program at Oregon State University

  Purpose of the Study The purpose of this study was to determine if upper division, undergraduate, elementary education students would demonstrate a significant change in self-actualization as measured ...

  Citation × Citation Citation Abstract Copy Title: Self actualization of students participating in the junior block teacher education program at Oregon State University Author: Wiley, Robert Charles Purpose of the Study The purpose of this study was to determine if upper division, undergraduate, elementary education students would demonstrate a significant change in self-actualization as measured by the Personal Orientation Inventory following instruction in five (5) communication skills (paraphrasing, behavior description, description of own feelings, perception checking, feedback of information). Procedures A total of 136 students participated in experimental and control groups during the Fall and Winter terms of 1972-1973. All students were placed in two field practicum blocks, four and one-half days per week. Staff Associates (superior students selected each term) served approximately three days per week as liaisons in participating public elementary schools, and participated in staff planning meetings and methods seminars. The experimental students and Staff Associates participated in five communication skills seminars facilitated by the investigator. In addition, all experimental students participated in five building meetings facilitated by the Staff Associates. Each phase of experimental procedure was held on alternating weeks each term of the investigation. A pre- and post administration of the Personal Orientation Inventory was completed by all participants. The I (Inner-Directed) Scale was utilized in a one way analysis of variance and covariance with results significant at the .05 level. An investigator devised Descriptive Data Opinionaire was also utilized to obtain subjective data from each participant. Results and Implications From the results of the study, the following implications were drawn: 1. The five communication skills seminars and building meetings were not effective suggesting additional existing measuring instruments being utilized, a new measurement instrument be devised, and encounter group procedures be introduced into the program. 2. Earlier introduction of self development and follow up application in each participant's program was needed to allow student confirmation and maximum chance for statistical significance. 3. Strong support existed for preparation in communication skills. This suggested procedures utilized were purposeful, meaningful to the individual, and perhaps a necessary tool to be included in future curriculum planning. 4. In order to maintain and expand personalization and individualization of the Junior Block, additional time, faculty effort, and affective programming was needed. Recommendations From the implications of the study, the following recommendations were offered to further assist research in this area: 1. Individual building meetings and communication skills training should become an integral part of the Junior Block program. 2. Schools of Education should introduce or continue to develop teacher preparation programs that focus on affective as well as cognitive curricula. 3. Additional research should be implemented into the use of communication skills training as a significant influence in development toward self-actualization. 4. A replication of this investigation be done with a new investigator and a larger sample utilizing the same experimental design, to affirm or negate findings. 5. All present participants be administered the measuring instrument at the conclusion of student teaching to measure additional post-test gains. 6. Additional analysis of present data be completed to determine strengths and weaknesses of individual students in particular areas of self-actualization. 7. Additional analysis of present data be completed to determine any correlation between students and Staff Associates post-test score and grades received, and recommendations by teachers. Title: Self actualization of students participating in the junior block teacher education program at Oregon State University Author: Wiley, Robert Charles Purpose of the Study The purpose of this study was to determine if upper division, undergraduate, elementary education students would demonstrate a significant change in self-actualization as measured by the Personal Orientation Inventory following instruction in five (5) communication skills (paraphrasing, behavior description, description of own feelings, perception checking, feedback of information). Procedures A total of 136 students participated in experimental and control groups during the Fall and Winter terms of 1972-1973. All students were placed in two field practicum blocks, four and one-half days per week. Staff Associates (superior students selected each term) served approximately three days per week as liaisons in participating public elementary schools, and participated in staff planning meetings and methods seminars. The experimental students and Staff Associates participated in five communication skills seminars facilitated by the investigator. In addition, all experimental students participated in five building meetings facilitated by the Staff Associates. Each phase of experimental procedure was held on alternating weeks each term of the investigation. A pre- and post administration of the Personal Orientation Inventory was completed by all participants. The I (Inner-Directed) Scale was utilized in a one way analysis of variance and covariance with results significant at the .05 level. An investigator devised Descriptive Data Opinionaire was also utilized to obtain subjective data from each participant. Results and Implications From the results of the study, the following implications were drawn: 1. The five communication skills seminars and building meetings were not effective suggesting additional existing measuring instruments being utilized, a new measurement instrument be devised, and encounter group procedures be introduced into the program. 2. Earlier introduction of self development and follow up application in each participant's program was needed to allow student confirmation and maximum chance for statistical significance. 3. Strong support existed for preparation in communication skills. This suggested procedures utilized were purposeful, meaningful to the individual, and perhaps a necessary tool to be included in future curriculum planning. 4. In order to maintain and expand personalization and individualization of the Junior Block, additional time, faculty effort, and affective programming was needed. Recommendations From the implications of the study, the following recommendations were offered to further assist research in this area: 1. Individual building meetings and communication skills training should become an integral part of the Junior Block program. 2. Schools of Education should introduce or continue to develop teacher preparation programs that focus on affective as well as cognitive curricula. 3. Additional research should be implemented into the use of communication skills training as a significant influence in development toward self-actualization. 4. A replication of this investigation be done with a new investigator and a larger sample utilizing the same experimental design, to affirm or negate findings. 5. All present participants be administered the measuring instrument at the conclusion of student teaching to measure additional post-test gains. 6. Additional analysis of present data be completed to determine strengths and weaknesses of individual students in particular areas of self-actualization. 7. Additional analysis of present data be completed to determine any correlation between students and Staff Associates post-test score and grades received, and recommendations by teachers. Close