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• 271. [Article] Cytophotometric determinations of nuclear DNA content in tissues of the wax moth larva, Galleria mellonella Linnaeus

  The present study was undertaken to determine, by measurement of nuclear DNA, the degrees and frequencies of ploidy in the last larval instar of the moth Galleria mellonella Linnaeus. While such data have ...

  Citation × Citation Citation Abstract Copy Title: Cytophotometric determinations of nuclear DNA content in tissues of the wax moth larva, Galleria mellonella Linnaeus Author: Longo, Frank J., 1939- The present study was undertaken to determine, by measurement of nuclear DNA, the degrees and frequencies of ploidy in the last larval instar of the moth Galleria mellonella Linnaeus. While such data have been amassed for a wide variety of vertebrate tissues, few studies have been concerned with invertebrates and especially insects where somatic polyploidy is developed to an unusually high degree. Relative amounts of DNA were determined cytophotometrically on individual Feulgen-stained nuclei of hypodermis, ventriculus, fat cells, blood cells, anterior silk gland, and proventriculus. Graphs of the determined DNA values indicated the presence of nuclear classes falling into polyploid ratios, The majority of blood cell and fat cell nuclei had class I values (= diploid), while class II and III (= tetraploid and octoploid) DNA values represented about 17 to 20 percent of the total nuclear population. The majority of DNA values of the ventriculus nuclei fell into the second class while 6.8 percent were considered as class I. The hypodermal nuclei were mostly of class I, while class II values represented 5.5 percent of the total number of determinations. Nuclei of the proventriculus and the anterior silk gland showed a broad spectrum of DNA values ranging from classes IV to VIII including many intermediate values. The method of measurement was analyzed for sources of error. Various interpretations were offered for the variations in DNA values including the role of endomitosis, definitive polyploidy, aneuploidy, differential gene replication, etc. In the case of the anterior silk gland and the proventriculus a possible relationship between DNA amounts and ceIl activity is indicated. Title: Cytophotometric determinations of nuclear DNA content in tissues of the wax moth larva, Galleria mellonella Linnaeus Author: Longo, Frank J., 1939- The present study was undertaken to determine, by measurement of nuclear DNA, the degrees and frequencies of ploidy in the last larval instar of the moth Galleria mellonella Linnaeus. While such data have been amassed for a wide variety of vertebrate tissues, few studies have been concerned with invertebrates and especially insects where somatic polyploidy is developed to an unusually high degree. Relative amounts of DNA were determined cytophotometrically on individual Feulgen-stained nuclei of hypodermis, ventriculus, fat cells, blood cells, anterior silk gland, and proventriculus. Graphs of the determined DNA values indicated the presence of nuclear classes falling into polyploid ratios, The majority of blood cell and fat cell nuclei had class I values (= diploid), while class II and III (= tetraploid and octoploid) DNA values represented about 17 to 20 percent of the total nuclear population. The majority of DNA values of the ventriculus nuclei fell into the second class while 6.8 percent were considered as class I. The hypodermal nuclei were mostly of class I, while class II values represented 5.5 percent of the total number of determinations. Nuclei of the proventriculus and the anterior silk gland showed a broad spectrum of DNA values ranging from classes IV to VIII including many intermediate values. The method of measurement was analyzed for sources of error. Various interpretations were offered for the variations in DNA values including the role of endomitosis, definitive polyploidy, aneuploidy, differential gene replication, etc. In the case of the anterior silk gland and the proventriculus a possible relationship between DNA amounts and ceIl activity is indicated. Close

• 272. [Article] Investment and Development of Fishing Resources: A Real Options Approach

  The valuation of the opportunity to either invest or exploit a fishery is particularly difficult because of the high uncertainty concerning the resource price. The traditional net-present-value (NPV) and ...

  Citation × Citation Citation Abstract Copy Title: Investment and Development of Fishing Resources: A Real Options Approach Author: Murillas, Arantza Year: 2001 The valuation of the opportunity to either invest or exploit a fishery is particularly difficult because of the high uncertainty concerning the resource price. The traditional net-present-value (NPV) and other discounted-cash-flows (DCF) methods cannot properly capture the management's flexibility and strategic value aspects of a fishery, thus they may understate its value. The rationale for using an option-based approach to capital budgeting arises from its potential to conceptualize and quantify this flexibility, as new information arrives, to alter its operating strategy, to defer investments, to shut down (and restart) fishery development. Real Options valuation has traditionally been applied in the area of natural resource investments different from fishing resources. This paper presents a general bioeconomic model for the value of a fishery. It suffices to determine not only the value of the fishery when open and closed, but also the optimal policy for opening, closing and setting the harvest rate. Moreover, the paper turns to the valuation of a fishery investment opportunity and the optimal investment rule. The natural growth rate of fishing resource stock and the production function are those of the Schaefer model. Finally, results for the Pacific Yellowfin ~l~na are presented. Title: Investment and Development of Fishing Resources: A Real Options Approach Author: Murillas, Arantza Year: 2001 The valuation of the opportunity to either invest or exploit a fishery is particularly difficult because of the high uncertainty concerning the resource price. The traditional net-present-value (NPV) and other discounted-cash-flows (DCF) methods cannot properly capture the management's flexibility and strategic value aspects of a fishery, thus they may understate its value. The rationale for using an option-based approach to capital budgeting arises from its potential to conceptualize and quantify this flexibility, as new information arrives, to alter its operating strategy, to defer investments, to shut down (and restart) fishery development. Real Options valuation has traditionally been applied in the area of natural resource investments different from fishing resources. This paper presents a general bioeconomic model for the value of a fishery. It suffices to determine not only the value of the fishery when open and closed, but also the optimal policy for opening, closing and setting the harvest rate. Moreover, the paper turns to the valuation of a fishery investment opportunity and the optimal investment rule. The natural growth rate of fishing resource stock and the production function are those of the Schaefer model. Finally, results for the Pacific Yellowfin ~l~na are presented. Close

• 273. [Article] Ecological foot print of the postharvest losses in Tuna industry: A case of Sri Lanka

  presentation

  Citation × Citation Citation Abstract Copy Title: Ecological foot print of the postharvest losses in Tuna industry: A case of Sri Lanka Author: Amaralal, Lalith, Jayasooriya, Niroshan, De Silva, Achini, Trondsen, Torbjorn presentation Title: Ecological foot print of the postharvest losses in Tuna industry: A case of Sri Lanka Author: Amaralal, Lalith, Jayasooriya, Niroshan, De Silva, Achini, Trondsen, Torbjorn presentation Close

• 274. [Article] Response of winter wheat (Triticum aestivum L. Em. Thell) to nitrogen and chloride fertilization in the presence of take-all root rot (Gaeumannomyces graminis var. tritici Walker)

  Response from nitrogen and chloride fertilization was measured in field experiments on winter wheat (Triticum aestivum L. Em. Thell. var. 'Stephens' and 'Yamhill') grown in western Oregon in an environment ...

  Citation × Citation Citation Abstract Copy Title: Response of winter wheat (Triticum aestivum L. Em. Thell) to nitrogen and chloride fertilization in the presence of take-all root rot (Gaeumannomyces graminis var. tritici Walker) Author: Maatougui, Mohamed El Hadi Response from nitrogen and chloride fertilization was measured in field experiments on winter wheat (Triticum aestivum L. Em. Thell. var. 'Stephens' and 'Yamhill') grown in western Oregon in an environment with a range of susceptibility to take-all root rot (Gaumannomyces graminis var. tritici Walker). Cropping sequences and expected disease severity considered in the study were: first year wheat after clover (low risk of severe take-all root rot: Nixon I experiment), second year wheat with high disease infection in the previous crop (high risk of severe take-all root rot: Keyt II experiment), second year wheat with low disease infection in the previous crop (moderate risk of severe take-all root rot: Nixon II and Coon experiment), third year wheat (high risk of severe take-all root rot: Jones experiment), fifth year wheat (high risk of severe take-all root rot: Keyt II experiment), and eighteenth year wheat (take-all decline established: the pathogen is present in the soil but does not cause damage, Evers experiment). Nitrogen treatments were applied at 0, 67, 134, and 202 kg/ha in all experiments where wheat followed wheat and at 0, 45, 90, and 134 kg/ha in the experiment where wheat followed clover. Chloride treatments were applied at 0, 45, and 90 kg/ha in all experiments and a rate of 134 kg C1/ha was also used on the Jones experiment. Nitrogen was predominantly supplied from urea while ammonium chloride supplied chloride and ammonium sulfate supplied the crop requirement for sulfur (about 20 kg/ha). Fertilizers were top-dressed in split application with chloride and sulfur containing fertilizers applied first (February) and urea applied later (March) in all experiments but those conducted in the Nixon farm where a single fertilizer was applied in March. Crop response was measured through the effects of N and c1 treatments on dry matter production, plant nitrogen content, plant nitrogen uptake and plant percent nitrogen recovery, as well as grain yield, yield components, grain nitrogen content, grain protein content, grain nitrogen uptake, and grain percent nitrogen recovery. The results of the study strongly indicated that take-all root rot was only a problem in the Jones, Keyt I, and Keyt II experiments and was most severe in third year wheat (Jones experiment). This also was the only experiment with significant (p = 0.05) response from rates of 202 kg N/ha. Nitrogen fertilization was the main factor that greatly influenced the levels of the variables studied while chloride fertilization generally did not have a significant (p = 0.05) influence. 134 kg N/ha was generally the rate accounting for the best levels of each variable studied in all experiments except in the Jones experiment as precised earlier. Crop response was also affected by a relatively long 'dry' period (April 20th to June 20th), particularly in the experiment where take-all root rot was a problem. Levels of the variables studied accounted for by the optimum rates of N were consistently higher in the experiments where take-all root rot was not a problem than where it was a problem by the following amounts: dry matter yields-17%, plant nitrogen contents-18%, plant nitrogen uptake levels-30%, plant nitrogen recoveries-28%, grain yields-22%, grain nitrogen contents-only 4%, grain protein contents-only 2%, grain nitrogen uptake levels-26%, grain nitrogen recoveries-18%, and spikes/m²-24%. Title: Response of winter wheat (Triticum aestivum L. Em. Thell) to nitrogen and chloride fertilization in the presence of take-all root rot (Gaeumannomyces graminis var. tritici Walker) Author: Maatougui, Mohamed El Hadi Response from nitrogen and chloride fertilization was measured in field experiments on winter wheat (Triticum aestivum L. Em. Thell. var. 'Stephens' and 'Yamhill') grown in western Oregon in an environment with a range of susceptibility to take-all root rot (Gaumannomyces graminis var. tritici Walker). Cropping sequences and expected disease severity considered in the study were: first year wheat after clover (low risk of severe take-all root rot: Nixon I experiment), second year wheat with high disease infection in the previous crop (high risk of severe take-all root rot: Keyt II experiment), second year wheat with low disease infection in the previous crop (moderate risk of severe take-all root rot: Nixon II and Coon experiment), third year wheat (high risk of severe take-all root rot: Jones experiment), fifth year wheat (high risk of severe take-all root rot: Keyt II experiment), and eighteenth year wheat (take-all decline established: the pathogen is present in the soil but does not cause damage, Evers experiment). Nitrogen treatments were applied at 0, 67, 134, and 202 kg/ha in all experiments where wheat followed wheat and at 0, 45, 90, and 134 kg/ha in the experiment where wheat followed clover. Chloride treatments were applied at 0, 45, and 90 kg/ha in all experiments and a rate of 134 kg C1/ha was also used on the Jones experiment. Nitrogen was predominantly supplied from urea while ammonium chloride supplied chloride and ammonium sulfate supplied the crop requirement for sulfur (about 20 kg/ha). Fertilizers were top-dressed in split application with chloride and sulfur containing fertilizers applied first (February) and urea applied later (March) in all experiments but those conducted in the Nixon farm where a single fertilizer was applied in March. Crop response was measured through the effects of N and c1 treatments on dry matter production, plant nitrogen content, plant nitrogen uptake and plant percent nitrogen recovery, as well as grain yield, yield components, grain nitrogen content, grain protein content, grain nitrogen uptake, and grain percent nitrogen recovery. The results of the study strongly indicated that take-all root rot was only a problem in the Jones, Keyt I, and Keyt II experiments and was most severe in third year wheat (Jones experiment). This also was the only experiment with significant (p = 0.05) response from rates of 202 kg N/ha. Nitrogen fertilization was the main factor that greatly influenced the levels of the variables studied while chloride fertilization generally did not have a significant (p = 0.05) influence. 134 kg N/ha was generally the rate accounting for the best levels of each variable studied in all experiments except in the Jones experiment as precised earlier. Crop response was also affected by a relatively long 'dry' period (April 20th to June 20th), particularly in the experiment where take-all root rot was a problem. Levels of the variables studied accounted for by the optimum rates of N were consistently higher in the experiments where take-all root rot was not a problem than where it was a problem by the following amounts: dry matter yields-17%, plant nitrogen contents-18%, plant nitrogen uptake levels-30%, plant nitrogen recoveries-28%, grain yields-22%, grain nitrogen contents-only 4%, grain protein contents-only 2%, grain nitrogen uptake levels-26%, grain nitrogen recoveries-18%, and spikes/m²-24%. Close

• 275. [Article] Molecular Survey for the Invasive Leafminer Pest Liriomyza huidobrensis (Diptera: Agromyzidae) in California Uncovers Only the Native Pest Liriomyza langei

  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 the Entomological ...

  Citation × Citation Citation Abstract Copy Title: Molecular Survey for the Invasive Leafminer Pest Liriomyza huidobrensis (Diptera: Agromyzidae) in California Uncovers Only the Native Pest Liriomyza langei Author: Scheffer, Sonja J., Gaimari, Stephen D., Reitz, Stuart R., Lewis, Matthew L. 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 the Entomological Society of America and can be found at: http://www.bioone.org/loi/ecen. Title: Molecular Survey for the Invasive Leafminer Pest Liriomyza huidobrensis (Diptera: Agromyzidae) in California Uncovers Only the Native Pest Liriomyza langei Author: Scheffer, Sonja J., Gaimari, Stephen D., Reitz, Stuart R., Lewis, Matthew L. 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 the Entomological Society of America and can be found at: http://www.bioone.org/loi/ecen. Close

• 276. [Article] Pollen fidelity of Apis mellifera L. during pollination of Limnanthes alba Hartw. ex Benth. ssp. alba, Limnanthaceae

  Limnanthes alba, commonly known as meadowfoam is a popular commercial crop because its seed oil is composed of long carbon chains that provide it with high oxidative stability and consequently make it ...

  Citation × Citation Citation Abstract Copy Title: Pollen fidelity of Apis mellifera L. during pollination of Limnanthes alba Hartw. ex Benth. ssp. alba, Limnanthaceae Author: Watkins, Ann J. Limnanthes alba, commonly known as meadowfoam is a popular commercial crop because its seed oil is composed of long carbon chains that provide it with high oxidative stability and consequently make it a desirable ingredient in cosmetic products. As a commercial pollinator, the western honey bee, Apis mellifera, may be utilized to pollinate monocultures such as L. alba. The pollen fidelity of a pollinator with regard to its intended crop determines the efficiency and overall benefit of the pollinator’s presence in the field. This research examines pollen fidelity of A. mellifera with regard to L. alba in a commercial setting. The average L. alba proportion of total trapped pollen was determined to be 88.5%. The high fidelity of A. mellifera to L. alba suggests that it was beneficial to have a supplemental pollinator present, but to definitively determine that a comparative study would need to be performed. Title: Pollen fidelity of Apis mellifera L. during pollination of Limnanthes alba Hartw. ex Benth. ssp. alba, Limnanthaceae Author: Watkins, Ann J. Limnanthes alba, commonly known as meadowfoam is a popular commercial crop because its seed oil is composed of long carbon chains that provide it with high oxidative stability and consequently make it a desirable ingredient in cosmetic products. As a commercial pollinator, the western honey bee, Apis mellifera, may be utilized to pollinate monocultures such as L. alba. The pollen fidelity of a pollinator with regard to its intended crop determines the efficiency and overall benefit of the pollinator’s presence in the field. This research examines pollen fidelity of A. mellifera with regard to L. alba in a commercial setting. The average L. alba proportion of total trapped pollen was determined to be 88.5%. The high fidelity of A. mellifera to L. alba suggests that it was beneficial to have a supplemental pollinator present, but to definitively determine that a comparative study would need to be performed. Close

• 277. [Article] Winter wheat in continuous cropping systems (high precipitation zone)

  Revised November 2006.Reviewed July 2012. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Winter wheat in continuous cropping systems (high precipitation zone) Author: Wysocki, Donald John, 1952-, Lutcher, L. K. (Lawrence K.), Horneck, Donald Arthur, Hart, John M. (John Mervyn), 1947-, Petrie, S. E., Oregon State University. Extension Service, Corp, Mary K. Revised November 2006.Reviewed July 2012. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Winter wheat in continuous cropping systems (high precipitation zone) Author: Wysocki, Donald John, 1952-, Lutcher, L. K. (Lawrence K.), Horneck, Donald Arthur, Hart, John M. (John Mervyn), 1947-, Petrie, S. E., Oregon State University. Extension Service, Corp, Mary K. Revised November 2006.Reviewed July 2012. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 278. [Image] Evaluation of instream fish habitat restoration structures in Klamath River tributaries, 1988/1989

  	Annual Report For Interagency Agreement 14-16-0001-89508 EVALUATION OF INSTREAM FISH HABITAT RESTORATION STRUCTURES IN KLAMATH RIVER TRIBUTARIES 1988/1989 by A.D.Olson and J.R. West USDA-Forest Service, ...
  	Citation × Citation Citation Abstract Copy Title: Evaluation of instream fish habitat restoration structures in Klamath River tributaries, 1988/1989 Author: Olson, A. D. Year: 1989, 2008, 2006 Annual Report For Interagency Agreement 14-16-0001-89508 EVALUATION OF INSTREAM FISH HABITAT RESTORATION STRUCTURES IN KLAMATH RIVER TRIBUTARIES 1988/1989 by A.D.Olson and J.R. West USDA-Forest Service, Klamath National Forest 1312 Fairlane Road, Yreka, CA 96097 ABSTRACT Ten instream fish habitat techniques were evaluated to determine which most effectively restored salmonid spawning and/or rearing conditions. Structure stability was estimated based on how intact each structure remained (by percent) and its age, we then projected useful life for each structure type. Cost in 1989 dollars was used to determine cost per unit habitat area provided. Observed use by spawners was used to estimate total number of redds per structure (over its life). Cost of providing spawning habitat (cost per redd) was calculated by dividing estimated total redds by structure cost. Habitats resulting from instream structures were classified using the modified Bisson method and we determined the influence zone of each structure using physical variables to define habitat area. Structures were biologically sampled using direct underwater observation techniques described by Hankin and Reeves1 (1989). Two person dive teams used a "two-pass" method to enumerate and classify salmonids by species and age-class (0+, 1+ or older juveniles, and adults), noting the presence of other species. Fish use of structure affected habitat (post-modification) was compared to use of habitats like those present prior to structure placement (pre-modification). Comparison of "pre-modification" and "post-modification" fish standing crops resulted in a "net fish difference" which was divided by structure cost, yielding "cost per fish reared11. Boulder weirs, the most expensive structures investigated, did not affect enough surface area to make cost per unit of affected habitat reasonable. Cabled cover logs and digger logs (lowest cost structures) were very cost effective at altering physical habitat condition. We believe cost of physically modifying habitat area is only one factor that is important enough to effect success or failure of a large scale habitat restoration program. Assuming all other factors are of equal weight, lowest cost structures can provide the "best value". Modification prescribed to restore stable spawning habitat needs close scrutiny. We believe it is essential to know how the existing habitat is used by spawners by conducting spawning area use surveys which identify redd location and quantify habitat available during each spawning period. Boulder deflectors were best utilized by Chinook salmon spawners, however chinook spawner use of "traditional" structures (weirs backfilled with gravel) was disappointing. Backfilling of instream structures with suitable gravel is a practice that should be discontinued. Steelhead spawner use of structures which result in "pocket water" type spawning areas were heavily used. This habitat configuration proved most desirable when woody object cover was readily available to the spawners. The highest steelhead spawner use was associated with boulder groups with wood and boulder/rootwad groups. We found rearing structures which provided high habitat and cover diversity received the best response from juvenile fish. We observed fish use over one summer and saw dramatic unpredictable use changes even through this short time period. Fish rearing needs during other seasons may differ substantially from summer needs, therefore, suitability of modified habitat probably also changes. Digger logs, one of the least costly and simplest structures, provided the best increase in fish standing crop (fish/m2) for the lowest cost. We believe digger logs were well used by rearing fish because they are one of the most natural restoration structures investigated. Other structures which were well used (small weirs, deflectors, and boulder groups with attached wood) also seem to closely duplicate naturally productive habitats. Higher velocity habitat types associated with boulder groups with wood, boulder rootwad groups, and boulder deflectors were selected by juvenile steelhead and chinook salmon. Providing overhead cover, especially if it extends into the water where it may also be used as object cover, seemed most valuable for juvenile steelhead and salmon if it was placed in a habitat type which would normally receive high fish use. Placement of object cover in slow velocity areas (pool and glide edges) had questionable value for summer rearing habitat restoration, however we do not know what value these structures may have during colder water high flow periods when fish seek slow velocity, densely-covered habitats. We defined the most cost effective method as one meeting restoration objectives, providing the greatest increase in fish use (per surface area or volume), over the longest time period, for the lowest cost. We rank structures evaluated in this study (from most cost-effective to least cost effective) as follows: Digger Logs, Boulder deflectors, Small Boulder Weirs, Boulder Groups with Woody Cover, Free Boulder Weirs, Large Boulder Weirs, Boulder Groups, Boulder/Rootwad Groups, Boulder/Rootwad Deflectors, Small Boulder Weirs, and Cabled Cover Logs. Title: Evaluation of instream fish habitat restoration structures in Klamath River tributaries, 1988/1989 Author: Olson, A. D. Year: 1989, 2008, 2006 Annual Report For Interagency Agreement 14-16-0001-89508 EVALUATION OF INSTREAM FISH HABITAT RESTORATION STRUCTURES IN KLAMATH RIVER TRIBUTARIES 1988/1989 by A.D.Olson and J.R. West USDA-Forest Service, Klamath National Forest 1312 Fairlane Road, Yreka, CA 96097 ABSTRACT Ten instream fish habitat techniques were evaluated to determine which most effectively restored salmonid spawning and/or rearing conditions. Structure stability was estimated based on how intact each structure remained (by percent) and its age, we then projected useful life for each structure type. Cost in 1989 dollars was used to determine cost per unit habitat area provided. Observed use by spawners was used to estimate total number of redds per structure (over its life). Cost of providing spawning habitat (cost per redd) was calculated by dividing estimated total redds by structure cost. Habitats resulting from instream structures were classified using the modified Bisson method and we determined the influence zone of each structure using physical variables to define habitat area. Structures were biologically sampled using direct underwater observation techniques described by Hankin and Reeves1 (1989). Two person dive teams used a "two-pass" method to enumerate and classify salmonids by species and age-class (0+, 1+ or older juveniles, and adults), noting the presence of other species. Fish use of structure affected habitat (post-modification) was compared to use of habitats like those present prior to structure placement (pre-modification). Comparison of "pre-modification" and "post-modification" fish standing crops resulted in a "net fish difference" which was divided by structure cost, yielding "cost per fish reared11. Boulder weirs, the most expensive structures investigated, did not affect enough surface area to make cost per unit of affected habitat reasonable. Cabled cover logs and digger logs (lowest cost structures) were very cost effective at altering physical habitat condition. We believe cost of physically modifying habitat area is only one factor that is important enough to effect success or failure of a large scale habitat restoration program. Assuming all other factors are of equal weight, lowest cost structures can provide the "best value". Modification prescribed to restore stable spawning habitat needs close scrutiny. We believe it is essential to know how the existing habitat is used by spawners by conducting spawning area use surveys which identify redd location and quantify habitat available during each spawning period. Boulder deflectors were best utilized by Chinook salmon spawners, however chinook spawner use of "traditional" structures (weirs backfilled with gravel) was disappointing. Backfilling of instream structures with suitable gravel is a practice that should be discontinued. Steelhead spawner use of structures which result in "pocket water" type spawning areas were heavily used. This habitat configuration proved most desirable when woody object cover was readily available to the spawners. The highest steelhead spawner use was associated with boulder groups with wood and boulder/rootwad groups. We found rearing structures which provided high habitat and cover diversity received the best response from juvenile fish. We observed fish use over one summer and saw dramatic unpredictable use changes even through this short time period. Fish rearing needs during other seasons may differ substantially from summer needs, therefore, suitability of modified habitat probably also changes. Digger logs, one of the least costly and simplest structures, provided the best increase in fish standing crop (fish/m2) for the lowest cost. We believe digger logs were well used by rearing fish because they are one of the most natural restoration structures investigated. Other structures which were well used (small weirs, deflectors, and boulder groups with attached wood) also seem to closely duplicate naturally productive habitats. Higher velocity habitat types associated with boulder groups with wood, boulder rootwad groups, and boulder deflectors were selected by juvenile steelhead and chinook salmon. Providing overhead cover, especially if it extends into the water where it may also be used as object cover, seemed most valuable for juvenile steelhead and salmon if it was placed in a habitat type which would normally receive high fish use. Placement of object cover in slow velocity areas (pool and glide edges) had questionable value for summer rearing habitat restoration, however we do not know what value these structures may have during colder water high flow periods when fish seek slow velocity, densely-covered habitats. We defined the most cost effective method as one meeting restoration objectives, providing the greatest increase in fish use (per surface area or volume), over the longest time period, for the lowest cost. We rank structures evaluated in this study (from most cost-effective to least cost effective) as follows: Digger Logs, Boulder deflectors, Small Boulder Weirs, Boulder Groups with Woody Cover, Free Boulder Weirs, Large Boulder Weirs, Boulder Groups, Boulder/Rootwad Groups, Boulder/Rootwad Deflectors, Small Boulder Weirs, and Cabled Cover Logs. Close

• 279. [Article] Effect of certain blood enzymes and cellular constituents on growth in different genetic groups of sheep

  In the present study, five breeds of ewes and their lambs were utilized. The breeds used were: Border Cheviot, Dorset Horn, Columbia, Suffolk and Willamette. In all, 31 ewes and 42 lambs were involved. The ...

  Citation × Citation Citation Abstract Copy Title: Effect of certain blood enzymes and cellular constituents on growth in different genetic groups of sheep Author: Hutto, Daniel C. In the present study, five breeds of ewes and their lambs were utilized. The breeds used were: Border Cheviot, Dorset Horn, Columbia, Suffolk and Willamette. In all, 31 ewes and 42 lambs were involved. The blood constituents which were determined for the ewes and lambs were: acid and alkaline phosphatase, hematocrit, hemoglobin and red and white blood cell numbers. Blood samples were taken and analyzed for each ewe and lamb, at two-week intervals, from the ninth or tenth day of lactation until approximately 94 days subsequent to lambing. At 100 days of age the lambs were scored for conformation and condition. Then the lambs were slaughtered and a sample of each carcass was cooked and submitted to a taste panel to obtain scores for tenderness and preference. Acid phosphatase levels of activity were approximately three times higher for lambs than for ewes at 10 days following lambing, and two times higher than the level for ewes for the entire testing period. Highly significant breed and period differences were observed for acid phosphatase levels in lambs. No breed differences for this enzyme were noted in ewes. Alkaline phosphatase levels of activity were higher in lambs than in ewes throughout the testing period. The average alkaline phosphatase value for lambs was 8.07 units compared to 2.96 units for the ewes. The average alkaline phosphatase value of lambs was highest at 10 days (11.00 units) and lowest at 80 days (6.36 units). Alkaline phosphatase levels were affected statistically (P<.01) by breed, sex and period, and ewe values were affected (P<.01) by breed, period and type of birth. Hematocrit values were only slightly higher in lambs than in ewes. At the first testing period the ewe values slightly exceeded the lamb values, but from the second period until the end of the test the lamb values were higher than the ewe values. Highly significant (P<.01) differences were found in ewes according to breed and period, whereas, lamb hematocrit values differed according to age of dam and period (P<.01). Hemoglobin levels followed a pattern similar to that found for hematocrit in lambs and ewes. Hemoglobin values for lambs and ewes reached the highest level at 24 days subsequent to lambing. Hemoglobin levels differed significantly (P<.01) in ewes according to breed and period, and in lambs according to period (P<.01) and sex (P<.05). Average red blood cell counts were higher for ewes (9,690,000) than for lambs (8,920,000) at 10 days subsequent to lambing, but by 94 days the average ewe red blood count was 8,440,000 compared to 10,680,000 for lambs. No breed differences could be found in red blood cell numbers for ewes or lambs. However, period and birth type differences were observed in lambs. White blood cell numbers were slightly more than one thousand lower for lambs than for ewes at 10 days following lambing. The lamb values were still lower than the ewe values at 24 days, but by 38 days the lamb values exceeded the ewe values. White blood cell numbers differed significantly (P<.01) for ewes according to breed and according to breed, birth type and period for lambs. A slight sex difference in white blood cell numbers was observed in lambs. The Columbia lambs had the lowest conformation and condition scores of any of the breeds. The Border Cheviots and the Willamettes had the highest scores for conformation and condition, respectively. However, the Columbias had the highest preference and tenderness scores of any of the breeds, while the Border Cheviots had the lowest preference and tenderness scores of any of the breeds. The breeds ranked in the following order for average weight gains of lambs: Willamettes, Suffolks, Columbias, Dorest Horns and Border Cheviots. Body weight of lambs differed significantly (P<.01) according to breed, birth type and period and (P<.05) according to sex. None of the variables studied seemed to be highly related to growth rate in lambs. Title: Effect of certain blood enzymes and cellular constituents on growth in different genetic groups of sheep Author: Hutto, Daniel C. In the present study, five breeds of ewes and their lambs were utilized. The breeds used were: Border Cheviot, Dorset Horn, Columbia, Suffolk and Willamette. In all, 31 ewes and 42 lambs were involved. The blood constituents which were determined for the ewes and lambs were: acid and alkaline phosphatase, hematocrit, hemoglobin and red and white blood cell numbers. Blood samples were taken and analyzed for each ewe and lamb, at two-week intervals, from the ninth or tenth day of lactation until approximately 94 days subsequent to lambing. At 100 days of age the lambs were scored for conformation and condition. Then the lambs were slaughtered and a sample of each carcass was cooked and submitted to a taste panel to obtain scores for tenderness and preference. Acid phosphatase levels of activity were approximately three times higher for lambs than for ewes at 10 days following lambing, and two times higher than the level for ewes for the entire testing period. Highly significant breed and period differences were observed for acid phosphatase levels in lambs. No breed differences for this enzyme were noted in ewes. Alkaline phosphatase levels of activity were higher in lambs than in ewes throughout the testing period. The average alkaline phosphatase value for lambs was 8.07 units compared to 2.96 units for the ewes. The average alkaline phosphatase value of lambs was highest at 10 days (11.00 units) and lowest at 80 days (6.36 units). Alkaline phosphatase levels were affected statistically (P<.01) by breed, sex and period, and ewe values were affected (P<.01) by breed, period and type of birth. Hematocrit values were only slightly higher in lambs than in ewes. At the first testing period the ewe values slightly exceeded the lamb values, but from the second period until the end of the test the lamb values were higher than the ewe values. Highly significant (P<.01) differences were found in ewes according to breed and period, whereas, lamb hematocrit values differed according to age of dam and period (P<.01). Hemoglobin levels followed a pattern similar to that found for hematocrit in lambs and ewes. Hemoglobin values for lambs and ewes reached the highest level at 24 days subsequent to lambing. Hemoglobin levels differed significantly (P<.01) in ewes according to breed and period, and in lambs according to period (P<.01) and sex (P<.05). Average red blood cell counts were higher for ewes (9,690,000) than for lambs (8,920,000) at 10 days subsequent to lambing, but by 94 days the average ewe red blood count was 8,440,000 compared to 10,680,000 for lambs. No breed differences could be found in red blood cell numbers for ewes or lambs. However, period and birth type differences were observed in lambs. White blood cell numbers were slightly more than one thousand lower for lambs than for ewes at 10 days following lambing. The lamb values were still lower than the ewe values at 24 days, but by 38 days the lamb values exceeded the ewe values. White blood cell numbers differed significantly (P<.01) for ewes according to breed and according to breed, birth type and period for lambs. A slight sex difference in white blood cell numbers was observed in lambs. The Columbia lambs had the lowest conformation and condition scores of any of the breeds. The Border Cheviots and the Willamettes had the highest scores for conformation and condition, respectively. However, the Columbias had the highest preference and tenderness scores of any of the breeds, while the Border Cheviots had the lowest preference and tenderness scores of any of the breeds. The breeds ranked in the following order for average weight gains of lambs: Willamettes, Suffolks, Columbias, Dorest Horns and Border Cheviots. Body weight of lambs differed significantly (P<.01) according to breed, birth type and period and (P<.05) according to sex. None of the variables studied seemed to be highly related to growth rate in lambs. Close

• 280. [Article] Factors affecting establishment, survival, and production of birdsfoot trefoil (Lotus corniculatus L.) and alfalfa (Medicago sativa L.)

  Field, greenhouse, growth chamber and laboratory experiments evaluated factors affecting establishment, survival and production of birdsfoot trefoil (Lotus corniculatus L.) and alfalfa (Medicago sativa ...

  Citation × Citation Citation Abstract Copy Title: Factors affecting establishment, survival, and production of birdsfoot trefoil (Lotus corniculatus L.) and alfalfa (Medicago sativa L.) Author: Cooper, Clee Scott Field, greenhouse, growth chamber and laboratory experiments evaluated factors affecting establishment, survival and production of birdsfoot trefoil (Lotus corniculatus L.) and alfalfa (Medicago sativa L.) Field studies investigated the effects of a barley companion crop, seedling year harvest management and nitrogen and phosphorus fertilization upon stands, survival and subsequent production of legumes. Seedings were made in each of two years. Stands of legumes were not affected by fertilization or harvest management, but decreased with increasing levels of companion crop competition. Death of seedlings occurred early in the establishment period and the degree of loss was similar for both species. Additional losses of plants did not occur during the establishment year. Losses of birdsfoot trefoil plants established with a companion crop occurred during the first winter following seeding. Stand reduction in the seeding year persisted for the duration of the experiment. Companion crops inhibited the growth of surviving seedlings. Growth inhibition was less when barley was clipped periodically than when it was matured to grain. In the absence of a companion crop, growth of seedlings was inhibited more by frequent clipping of thin weed stands than by allowing weeds to mature. Yields of weeds were inversely proportional to density of barley plants. Wild oats was more detrimental to seedling growth and was less readily controlled by clipping than redroot pigweed or pigeon grass. The percentage of solar radiation intercepted by barley varied from 89 in early morning or late evening to 22 at noon. Light intensity was reduced more by barley in early season and less by barley in late season than by wild oats. Yields of mixtures in the year after seeding were reduced as a result of establishment with a companion crop and to a greater degree and for a longer period of time when barley had been allowed to mature. Yield reductions of legumes were compensated for by increased grass yields. Grass grown with birdsfoot trefoil yielded significantly more in early season and significantly less in late season than grass grown with alfalfa. Greenhouse studies evaluated the influenee of soil temperature and phosphorus fertilization upon growth and phosphorus uptake of birdsfoot trefoil and alfalfa. Root growth of both species increased with increasing soil temperatures. Weight of alfalfa roots was twice that of birdsfoot trefoil at all temperatures. Top growth of birdsfoot trefoil increaeed to a greater degree than that of alfalfa with increasing temperature. The greater top growth of birdsfoot trefoil resulted in reduced root-shoot ratios. Birdsfoot trefoil produced less dry matter per cm.² of leaf area than alfalfa. Root growth of both species increased with increasing applications of P fertilizer. Phosphorus appeared to be more important to growth at low than at high temperatures. Phosphorus and nitrogen uptake by both species increased with increasing soil temperature. Growth chamber studies evaluated the influence of low light intensities and seedling age upon growth of seedlings and distribution of accumulated dry matter. Seedlings gained weight at light intensities of 200 to 800 f.c. With decreasing light intensity, stem elongation occurred at the expense of roots. A smaller percentage of accumulated dry matter went into roots of two-week than in older seedlings. Roots of two-week old seedlings of alfalfa lost weight at 200 f.c. Laboratory studies evaluated oxygen uptake of germinating birdsfoot trefoil and alfalfa seeds. Average oxygen uptake by both species on a per unit weight basis was similar. Alfalfa, due to its greater size, had a greater oxygen uptake on a per plant basis than did birdsfoot trefoil. Title: Factors affecting establishment, survival, and production of birdsfoot trefoil (Lotus corniculatus L.) and alfalfa (Medicago sativa L.) Author: Cooper, Clee Scott Field, greenhouse, growth chamber and laboratory experiments evaluated factors affecting establishment, survival and production of birdsfoot trefoil (Lotus corniculatus L.) and alfalfa (Medicago sativa L.) Field studies investigated the effects of a barley companion crop, seedling year harvest management and nitrogen and phosphorus fertilization upon stands, survival and subsequent production of legumes. Seedings were made in each of two years. Stands of legumes were not affected by fertilization or harvest management, but decreased with increasing levels of companion crop competition. Death of seedlings occurred early in the establishment period and the degree of loss was similar for both species. Additional losses of plants did not occur during the establishment year. Losses of birdsfoot trefoil plants established with a companion crop occurred during the first winter following seeding. Stand reduction in the seeding year persisted for the duration of the experiment. Companion crops inhibited the growth of surviving seedlings. Growth inhibition was less when barley was clipped periodically than when it was matured to grain. In the absence of a companion crop, growth of seedlings was inhibited more by frequent clipping of thin weed stands than by allowing weeds to mature. Yields of weeds were inversely proportional to density of barley plants. Wild oats was more detrimental to seedling growth and was less readily controlled by clipping than redroot pigweed or pigeon grass. The percentage of solar radiation intercepted by barley varied from 89 in early morning or late evening to 22 at noon. Light intensity was reduced more by barley in early season and less by barley in late season than by wild oats. Yields of mixtures in the year after seeding were reduced as a result of establishment with a companion crop and to a greater degree and for a longer period of time when barley had been allowed to mature. Yield reductions of legumes were compensated for by increased grass yields. Grass grown with birdsfoot trefoil yielded significantly more in early season and significantly less in late season than grass grown with alfalfa. Greenhouse studies evaluated the influenee of soil temperature and phosphorus fertilization upon growth and phosphorus uptake of birdsfoot trefoil and alfalfa. Root growth of both species increased with increasing soil temperatures. Weight of alfalfa roots was twice that of birdsfoot trefoil at all temperatures. Top growth of birdsfoot trefoil increaeed to a greater degree than that of alfalfa with increasing temperature. The greater top growth of birdsfoot trefoil resulted in reduced root-shoot ratios. Birdsfoot trefoil produced less dry matter per cm.² of leaf area than alfalfa. Root growth of both species increased with increasing applications of P fertilizer. Phosphorus appeared to be more important to growth at low than at high temperatures. Phosphorus and nitrogen uptake by both species increased with increasing soil temperature. Growth chamber studies evaluated the influence of low light intensities and seedling age upon growth of seedlings and distribution of accumulated dry matter. Seedlings gained weight at light intensities of 200 to 800 f.c. With decreasing light intensity, stem elongation occurred at the expense of roots. A smaller percentage of accumulated dry matter went into roots of two-week than in older seedlings. Roots of two-week old seedlings of alfalfa lost weight at 200 f.c. Laboratory studies evaluated oxygen uptake of germinating birdsfoot trefoil and alfalfa seeds. Average oxygen uptake by both species on a per unit weight basis was similar. Alfalfa, due to its greater size, had a greater oxygen uptake on a per plant basis than did birdsfoot trefoil. Close