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• 1. [Article] Substitutional relationships between rainbow trout and pansize salmon : a market demand analysis

  The fundamental objective of this analysis was to isolate and identify the factors governing the demand for domestically produced rainbow trout in a representative west coast market, and assess the impact ...

  Citation × Citation Citation Abstract Copy Title: Substitutional relationships between rainbow trout and pansize salmon : a market demand analysis Author: Queirolo, Lewis E. The fundamental objective of this analysis was to isolate and identify the factors governing the demand for domestically produced rainbow trout in a representative west coast market, and assess the impact on that demand, if any, of the introduction of pansize salmon. The approach taken in this market demand study was to identify those variables hypothesized to determine supply and demand for rainbow trout. Several testable hypotheses concerning the anticipated relationships were specified. It was hypothesized that a negative relationship would exist between the price of trout at the brokerage level and the quantity demanded at that level. Conversely, the price of trout at the wholesale level was hypothesized to be positively correlated with the quantity of rainbow trout demanded at the brokerage level. Further, the signs on the coefficients of variables accounting for the wholesale prices of substitute items were expected to be negative, while comparable prices at the brokerage level should be positive, based upon the hypothesis. It was hypothesized that the presence of Japanese trout in the market place would have a negative impact on the quantity of domestically produced trout demanded. Personal disposable income was hypothesized to be positively correlated with the quantity of trout demanded. Expectations were that seasonal factors tend to cause trout demand to fluctuate cyclically. An econometric simultaneous equations model was specified from which estimates of the parameters of the demand equation were obtained using Two Stage Least Squares techniques. A recognition of the limitations associated with the available data set necessitates the emphasizing of the preliminary nature of these results. Data on quantities and prices of rainbow trout and equivalent price series for hypothesized substitutes were obtained through personal interviews with market participants and close observers thereof. The results of the study, while preliminary, tend to support the original set of hypotheses concerning the interrelationships between quantity of domestic trout demanded and own-price, the price of close substitutes and seasonal demand fluctuations. Somewhat unexpectedly, the regression seems to have uncovered a negative income/quantity demanded relationship for rainbow trout. This raises some interesting questions which might best be addressed in terms of hypotheses for future analysis. Title: Substitutional relationships between rainbow trout and pansize salmon : a market demand analysis Author: Queirolo, Lewis E. The fundamental objective of this analysis was to isolate and identify the factors governing the demand for domestically produced rainbow trout in a representative west coast market, and assess the impact on that demand, if any, of the introduction of pansize salmon. The approach taken in this market demand study was to identify those variables hypothesized to determine supply and demand for rainbow trout. Several testable hypotheses concerning the anticipated relationships were specified. It was hypothesized that a negative relationship would exist between the price of trout at the brokerage level and the quantity demanded at that level. Conversely, the price of trout at the wholesale level was hypothesized to be positively correlated with the quantity of rainbow trout demanded at the brokerage level. Further, the signs on the coefficients of variables accounting for the wholesale prices of substitute items were expected to be negative, while comparable prices at the brokerage level should be positive, based upon the hypothesis. It was hypothesized that the presence of Japanese trout in the market place would have a negative impact on the quantity of domestically produced trout demanded. Personal disposable income was hypothesized to be positively correlated with the quantity of trout demanded. Expectations were that seasonal factors tend to cause trout demand to fluctuate cyclically. An econometric simultaneous equations model was specified from which estimates of the parameters of the demand equation were obtained using Two Stage Least Squares techniques. A recognition of the limitations associated with the available data set necessitates the emphasizing of the preliminary nature of these results. Data on quantities and prices of rainbow trout and equivalent price series for hypothesized substitutes were obtained through personal interviews with market participants and close observers thereof. The results of the study, while preliminary, tend to support the original set of hypotheses concerning the interrelationships between quantity of domestic trout demanded and own-price, the price of close substitutes and seasonal demand fluctuations. Somewhat unexpectedly, the regression seems to have uncovered a negative income/quantity demanded relationship for rainbow trout. This raises some interesting questions which might best be addressed in terms of hypotheses for future analysis. Close

• 2. [Article] Life history of rainbow trout and considerations for introducing steelhead into southern Chile

  Citation × Citation Citation Abstract Copy Title: Life history of rainbow trout and considerations for introducing steelhead into southern Chile Author: Poblete Arellano, Tirso S. Title: Life history of rainbow trout and considerations for introducing steelhead into southern Chile Author: Poblete Arellano, Tirso S. Close

• 3. [Article] Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss Author: Schreck, Carl B., Noakes, David L.G., Yada, Takashi, Matsuda, Hiroyuki, Miura, Go, Munakata, Arimune To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Title: Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss Author: Schreck, Carl B., Noakes, David L.G., Yada, Takashi, Matsuda, Hiroyuki, Miura, Go, Munakata, Arimune To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Close

• 4. [Article] Acute and chronic toxicity studies with monochlorobenzene in rainbow trout

  The toxicity of chlorobenzene (CB) was investigated in rainbow trout following acute ip administration (1. 0 ml/kg, 1:1 in corn oil) and chronic exposure (2. 1 ppm and 2. 9 ppm) via the water in a continuously flowing ...

  Citation × Citation Citation Abstract Copy Title: Acute and chronic toxicity studies with monochlorobenzene in rainbow trout Author: Dalich, George M. The toxicity of chlorobenzene (CB) was investigated in rainbow trout following acute ip administration (1. 0 ml/kg, 1:1 in corn oil) and chronic exposure (2. 1 ppm and 2. 9 ppm) via the water in a continuously flowing system for 15 and 30 days. In the acute study, overt toxicity and hepatotoxicity were monitored over a 96 hour time period. Variables measured to assess toxicity included LD50 determination, weight changes, liver weight to body weight ratios, behavioral changes, alanine aminotransferase activity (GPT), sulfobromophthalein (BSP) retention, total plasma protein concentration and liver histopathology. In the chronic study the same measures of toxicity were followed as well as respiratory rates, oxygen consumption, food consumption, alkaline phosphatase (AP) activity, and serum protein electrophoresis. The 72 hour LD50 of CB in rainbow trout after acute intoxication was 1.8 ml/kg. The toxicant caused behavioral changes in the fish which were consistent with the known anesthetic properties of CB in mammals. Elevations in BSP retention and GPT activity, and histopathology indicated that CB was hepatotoxic in the fish. The LC50 of CB in trout exposed via the water for 96 hours was 4.7 ppm. Chronic exposure of trout to CB resulted in similar behavioral changes as seen in the acute study. Liver toxicity was evident from elevations in GPT activity and decreased A/G ratios of serum proteins after 15 days of exposure. BSP retention and AP activity appeared to be affected by the nutritional status of the trout as much as by the CB treatment. After 30 days of exposure to CB, trout appeared to have adapted to the toxic effects of CB. These results indicate that CB is toxic to rainbow trout after either acute intoxication or chronic exposure via the water. Behavioral and soft organ toxicity of CB seen in this study may compromise the ability of the trout to thrive in its environment. Title: Acute and chronic toxicity studies with monochlorobenzene in rainbow trout Author: Dalich, George M. The toxicity of chlorobenzene (CB) was investigated in rainbow trout following acute ip administration (1. 0 ml/kg, 1:1 in corn oil) and chronic exposure (2. 1 ppm and 2. 9 ppm) via the water in a continuously flowing system for 15 and 30 days. In the acute study, overt toxicity and hepatotoxicity were monitored over a 96 hour time period. Variables measured to assess toxicity included LD50 determination, weight changes, liver weight to body weight ratios, behavioral changes, alanine aminotransferase activity (GPT), sulfobromophthalein (BSP) retention, total plasma protein concentration and liver histopathology. In the chronic study the same measures of toxicity were followed as well as respiratory rates, oxygen consumption, food consumption, alkaline phosphatase (AP) activity, and serum protein electrophoresis. The 72 hour LD50 of CB in rainbow trout after acute intoxication was 1.8 ml/kg. The toxicant caused behavioral changes in the fish which were consistent with the known anesthetic properties of CB in mammals. Elevations in BSP retention and GPT activity, and histopathology indicated that CB was hepatotoxic in the fish. The LC50 of CB in trout exposed via the water for 96 hours was 4.7 ppm. Chronic exposure of trout to CB resulted in similar behavioral changes as seen in the acute study. Liver toxicity was evident from elevations in GPT activity and decreased A/G ratios of serum proteins after 15 days of exposure. BSP retention and AP activity appeared to be affected by the nutritional status of the trout as much as by the CB treatment. After 30 days of exposure to CB, trout appeared to have adapted to the toxic effects of CB. These results indicate that CB is toxic to rainbow trout after either acute intoxication or chronic exposure via the water. Behavioral and soft organ toxicity of CB seen in this study may compromise the ability of the trout to thrive in its environment. Close

• 5. [Article] A population study of the rainbow trout (Salmo gairdneri) in a Central Oregon stream

  The rainbow trout population in Elder Creek, Oregon was studied between June 1965 and November 1966. The physical characteristics of the stream during the summer season were described. Rainbow trout were ...

  Citation × Citation Citation Abstract Copy Title: A population study of the rainbow trout (Salmo gairdneri) in a Central Oregon stream Author: Osborn, Charles Edwin The rainbow trout population in Elder Creek, Oregon was studied between June 1965 and November 1966. The physical characteristics of the stream during the summer season were described. Rainbow trout were captured in each of three sections on the stream by electrofishing and were tagged and measured. Population size, mortality, recruitment, growth rate, and production was estimated for fish in each section where data were sufficient. Estimates were made of the yield of trout to the sport fishery. The water in Elder Creek is relatively low in concentration of dissolved solids. The stream lies in a canyon of mostly bedrock and large cobbles with very little spawning gravel. Water temperature was found to be near the maximum for trout suitability in the lower reaches of the stream. Reliable estimates of population size and their variation were obtained within the summer of 1966. Population size estimates for the summer of 1965 were not reliable because of the small numbers of trout that could be obtained during this period. Therefore estimates of annual rates of mortality, growth, and production were not possible, Growth rates were estimated for marked and for unmarked fish during the summer of 1966. Marked fish were found to have a markedly lower growth than unmarked fish. Of 755 observations of trout movement during the study less than four percent were found to have moved more than 300 feet. Immigration of adult fish into the population was either insignificant or not detectable. Although Elder Creek has a good population of legal-sized native trout, fishing pressure on the stream is relatively light. The lower reaches are fished more heavily than the headwaters, which probably receive no angling pressure during some fishing seasons. Title: A population study of the rainbow trout (Salmo gairdneri) in a Central Oregon stream Author: Osborn, Charles Edwin The rainbow trout population in Elder Creek, Oregon was studied between June 1965 and November 1966. The physical characteristics of the stream during the summer season were described. Rainbow trout were captured in each of three sections on the stream by electrofishing and were tagged and measured. Population size, mortality, recruitment, growth rate, and production was estimated for fish in each section where data were sufficient. Estimates were made of the yield of trout to the sport fishery. The water in Elder Creek is relatively low in concentration of dissolved solids. The stream lies in a canyon of mostly bedrock and large cobbles with very little spawning gravel. Water temperature was found to be near the maximum for trout suitability in the lower reaches of the stream. Reliable estimates of population size and their variation were obtained within the summer of 1966. Population size estimates for the summer of 1965 were not reliable because of the small numbers of trout that could be obtained during this period. Therefore estimates of annual rates of mortality, growth, and production were not possible, Growth rates were estimated for marked and for unmarked fish during the summer of 1966. Marked fish were found to have a markedly lower growth than unmarked fish. Of 755 observations of trout movement during the study less than four percent were found to have moved more than 300 feet. Immigration of adult fish into the population was either insignificant or not detectable. Although Elder Creek has a good population of legal-sized native trout, fishing pressure on the stream is relatively light. The lower reaches are fished more heavily than the headwaters, which probably receive no angling pressure during some fishing seasons. Close

• 6. [Article] Accumulation of dietary polychlorinated biphenyl by rainbow trout (Salmo gairdneri)

  Citation × Citation Citation Abstract Copy Title: Accumulation of dietary polychlorinated biphenyl by rainbow trout (Salmo gairdneri) Author: Lieb, Andrew James Title: Accumulation of dietary polychlorinated biphenyl by rainbow trout (Salmo gairdneri) Author: Lieb, Andrew James Close

• 7. [Article] The characterization of the MFO system in rainbow trout fed cruciferous vegetables

  Several compounds have been shown to induce the mixed function oxidase enzyme system of animals, and also to inhibit tumor formation. Included in this category are several vegetables and isolated vegetable ...

  Citation × Citation Citation Abstract Copy Title: The characterization of the MFO system in rainbow trout fed cruciferous vegetables Author: Haight, Lynn Ellen Several compounds have been shown to induce the mixed function oxidase enzyme system of animals, and also to inhibit tumor formation. Included in this category are several vegetables and isolated vegetable components from the Cruciferae family. In this study rainbow trout were fed blanched freeze-dried cauliflower, broccoli, or Brussel sprouts at the 20% supplemental level for two months, or 500 ppm benzyl or phenethyl isothiocyanate. At this time the livers were removed and hepatic microsomal enzymes were studied. This treatment did not cause any increases in the metabolism of p-nitroanisole or benzo(a)pyrene and cytochrome P-450 levels were not elevated. On the contrary, benzo(a)pyrene monooxygenase, 7-ethoxycoumarin 0-dealkylase, resorufin 0-dealkylase, p-nitroanisole 0-demethylase, and cytochrome P-450 levels were increased in trout treated orally and intraperitoneally with β-napthoflavone. For all parameters studied, a greater increase in activity was seen in the trout treated intraperitoneally. The vegetable and isothiocyanate supplemented diets also did not inhibit tumor formation in trout challenged with 20 ppb aflatoxin B₁ for one month. A study with rats showed that both blanched freeze-dried cauliflower and air-dried cauliflower cause significant increases in p-nitroanisole 0-demethylase activity and benzo(a)pyrene monooxygenase activity and increased cytochrome P-450 levels in rat hepatic microsomes when fed at the 20% supplemental level for 25 days. It was concluded that the null effects seen with the trout fed the vegetables and isothiocyanates were not due to the heat treatment of the vegetables since rats fed blanched freeze-dried cauliflower had significant increases in enzymatic activity and increased cytochrome P-450 levels over controls. The results of the β-napthoflavone experiment verified the validity and reliability of the experimental assays and conditions and showed that trout hepatic microsomal enzymes can be induced by orally administered compounds. Title: The characterization of the MFO system in rainbow trout fed cruciferous vegetables Author: Haight, Lynn Ellen Several compounds have been shown to induce the mixed function oxidase enzyme system of animals, and also to inhibit tumor formation. Included in this category are several vegetables and isolated vegetable components from the Cruciferae family. In this study rainbow trout were fed blanched freeze-dried cauliflower, broccoli, or Brussel sprouts at the 20% supplemental level for two months, or 500 ppm benzyl or phenethyl isothiocyanate. At this time the livers were removed and hepatic microsomal enzymes were studied. This treatment did not cause any increases in the metabolism of p-nitroanisole or benzo(a)pyrene and cytochrome P-450 levels were not elevated. On the contrary, benzo(a)pyrene monooxygenase, 7-ethoxycoumarin 0-dealkylase, resorufin 0-dealkylase, p-nitroanisole 0-demethylase, and cytochrome P-450 levels were increased in trout treated orally and intraperitoneally with β-napthoflavone. For all parameters studied, a greater increase in activity was seen in the trout treated intraperitoneally. The vegetable and isothiocyanate supplemented diets also did not inhibit tumor formation in trout challenged with 20 ppb aflatoxin B₁ for one month. A study with rats showed that both blanched freeze-dried cauliflower and air-dried cauliflower cause significant increases in p-nitroanisole 0-demethylase activity and benzo(a)pyrene monooxygenase activity and increased cytochrome P-450 levels in rat hepatic microsomes when fed at the 20% supplemental level for 25 days. It was concluded that the null effects seen with the trout fed the vegetables and isothiocyanates were not due to the heat treatment of the vegetables since rats fed blanched freeze-dried cauliflower had significant increases in enzymatic activity and increased cytochrome P-450 levels over controls. The results of the β-napthoflavone experiment verified the validity and reliability of the experimental assays and conditions and showed that trout hepatic microsomal enzymes can be induced by orally administered compounds. Close

• 8. [Article] Correlations between rainbow trout (Salmo gairdneri) populations and stream environments in Eastern Oregon streams

  Citation × Citation Citation Abstract Copy Title: Correlations between rainbow trout (Salmo gairdneri) populations and stream environments in Eastern Oregon streams Author: Grimes, Terry Neill Title: Correlations between rainbow trout (Salmo gairdneri) populations and stream environments in Eastern Oregon streams Author: Grimes, Terry Neill Close

• 9. [Article] Shrimp processing waste as a pigment source for rainbow trout (Salmo gairdneri)

  Citation × Citation Citation Abstract Copy Title: Shrimp processing waste as a pigment source for rainbow trout (Salmo gairdneri) Author: Steel, Ronald Edward Title: Shrimp processing waste as a pigment source for rainbow trout (Salmo gairdneri) Author: Steel, Ronald Edward Close

• 10. [Article] The essential fatty acid requirements of rainbow trout (Salmon gairdneri)

  Citation × Citation Citation Abstract Copy Title: The essential fatty acid requirements of rainbow trout (Salmon gairdneri) Author: Castell, John Daniel Title: The essential fatty acid requirements of rainbow trout (Salmon gairdneri) Author: Castell, John Daniel Close