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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Evaluation of amino acid supplementation of soybean-meal-based diets for hybrid striped bass

Savolainen, Lea Christine 15 May 2009 (has links)
Hybrid striped bass (Morone chrysops x M. saxatilis) aquaculture is a major commercial enterprise in the United States and internationally. Efforts to decrease diet costs and limit dependence on fishmeal, have led to the development of plant-based diets as an alternative aquafeed. Due to limiting concentrations of amino acids such as methionine, cystine, and taurine in plant meals such as soybean meal, supplementation of these plant-based diets with methionine or other sulfur amino acid compounds is typically required. Therefore, the current study was conducted to evaluate different amino acid supplements in soybean-meal-based diets for hybrid striped bass for possible refinement of diets and reduction of production costs. One feeding trial evaluated methionine hydroxy analog (MHA) and Mintrex® which is MHA containing chelated zinc relative to L-methionine. The second trial evaluated the effects of supplemental taurine or arginine on fish performance and potential health benefits. In the first feeding trial, a basal soybean-meal-based diet (56% soybean meal and 15% fishmeal) marginally deficient in total sulfur amino acids (TSSA) (1.10% methionine and cystine) was supplemented with either L-methionine, Mintrex® or MHA calcium salt and fed to triplicate groups of juvenile hybrid striped bass for 10 weeks. The different methionine supplements provided similar weight gain, feed efficiency ratio (FER) and protein efficiency ratio (PER) values that tended to be greater than observed in fish fed the basal diet. Mintrex® supplementation provided much higher plasma zinc concentrations compared to fish fed the other methionine supplements. In the second feeding trial, soybean-meal based diets which satisfied the requirement for TSAA were supplemented with either taurine or arginine at 1.5% of dry weight. Supplemental taurine or arginine did not provide any improvements in weight gain, FER, PER or survival compared to the basal diet. Thus, taurine or arginine supplementation of soybean-meal-based diets does not appear warranted. However, sulfur amino acid supplementation of plant-based diets is critical, and Mintrex® appears to be an effective supplement to meet the methionine and zinc needs of hybrid striped bass.
52

Kefal balığından havyar üretimi ve kalitesinin belirlenmesi /

Karakaş, Yavuz. Diler, Abdullah. January 2008 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Su Ürünleri Yetiştiriciliği Anabilim Dalı, 2008. / Kaynakça var.
53

TEMPORAL DISTRIBUTION OF MORONE SAXATILIS EGGS AND LARVAE AND NEOMYSIS AMERICANA IN THE SHUBENACADIE ESTUARY

Reesor, Craig 23 July 2012 (has links)
In the Maritimes, only two striped bass spawning populations remain: the Miramichi River in New Brunswick and the Shubenacadie – Stewiacke system in Nova Scotia. The Shubenacadie – Stewiacke system is subjected to a well pronounced twice daily tidal bore which induces dramatic changes in water parameters and challenges pelagic life. This system will be subject to potential change through brine discharge, a by-product of the Alton Natural Gas Storage Project. . Examining the temporal distribution of mysids, striped bass eggs and larvae at a fixed location around the Alton Project site will provide baseline information on population structure and insights into how egg and larvae distributions change with respect to tidal cycles, temperature and salinity. Surface plankton net tows from the top 0.75m of the water column were used to collect mysids, striped bass eggs and larvae over 14 months over two years. Daily mean egg abundance surpassed 1000 eggs/m3 once in 2008. A decrease of 1.9 °C in water temperature at the Alton Project site coincided with a cessation of eggs, and presumably, spawning. Spawning resumed when temperatures surpassed 15 °C. In contrast, the largest spawning event of the 2009 season occurred as water temperatures decreased (14 to 12.7 °C). The 2009 spawning season was longer (49 days) than 2008 (31 days) by 18 days, and in both years spawning peaked within the last week of May and first week of June. Two large spawning events, over 4000 daily mean eggs/m3 apiece, were detected May 24 and June 2, 2009. Mysids were present in high numbers throughout May to November, with some tows greater than 14,000 individuals/m3 in June 2008 and August 2009. Over the length of the ebb tide, as salinity decreases, mysid abundance also decreased. Whereas, striped bass egg abundance was consistently lowest at high tide and increased progressively over about 300 minutes through the ebb tide. Both striped bass larvae and mysids displayed patchiness in their temporal distribution suggesting passive transport in the this system. In both 2008 and 2009, larvae were detected at the Alton Project site for 38 days. The colder temperatures and larger tidal range of 2009, coupled with large increase in rainfall during the larval season contributed to the over 30-fold lower abundance over that found in 2008. When abundance was related in concert with temperature and salinity, mysids were ever present at high abundances except on three occasions. Mysid abundance decreased when salinity dropped beneath 5 ‰ during both years, and in 2008 when temperatures were lower than 15 °C. Salinity was impacted according to a seven-day lag after rainfall in both years, although the minimum volume of rainfall and associated impact on salinity have yet to be described.
54

Phenology of Crucifer and Striped Flea Beetles, and Potential of the Anthranilic Diamide Insecticide, Cyantraniliprole, as a Canola Seed Treatment for Control of Flea Beetles

Irwin, Caleigh 16 September 2011 (has links)
This research investigated the phenology of the striped flea beetle (Phyllotreta striolata (Fabricius) (SFB) and crucifer flea beetle (Phyllotreta cruciferae (Goeze)) (CFB), and examined the efficacy and the persistence of biological activity of the reduced-risk insecticides cyantraniliprole, clothianidin, and thiamethoxam applied as seed treatments to spring canola. Yellow sticky cards were placed around field perimeters in order to assess if CFB and SFB have synchronous phenology. It was found that CFB and SFB have largely asynchronous populations in southern Ontario. In laboratory bioassays, while flea beetle control with cyantraniliprole was comparable to that provided by thiamethoxam or clothianidin at the cotyledon stage, control did not persist through the 1st and 2nd leaf stages. Thiamethoxam and clothianidin both provided moderate control of flea beetles in both 1st and 2nd leaves. Field studies suggested that cyantraniliprole may offer control of flea beetles comparable to that provided by thiamethoxam and clothianidin. / E.I. DuPont Canada Co.
55

Evaluation of Whole and Lipid-Extracted Algae Meals (LEA) in the Diet of Juvenile Red Drum (Sciaenops ocellatus) and Digestibility of LEA by Red Drum and Hybrid Striped Bass (Morone chrysops x Morone saxatilis)

Patterson, Donovan Aaron 03 October 2013 (has links)
As aquaculture continues to expand, protein sources have become more costly and less available. Simultaneously, lipid-extracted algal meals (LEA) (co-products of bio-diesel production) are becoming increasingly available as alternative sources of energy are investigated. By integrating LEA into aquaculture diets, feed prices could be lowered and bio-diesel production would have an additional revenue stream. Three feeding trials each of 7 weeks duration were conducted to evaluate five different algal meals as partial replacements for fishmeal and soy protein concentrate in diets for juvenile red drum (Sciaenops ocellatus). Apparent digestibility coefficients (ADCs) for CP and energy in various LEAs also were determined with red drum and hybrid striped bass (HSB). In the first trial, whole algae meal and LEA derived from Navicula sp. replaced 5 or 10% of the crude protein (CP) in the reference diet. Weight gain, feed efficiency (FE), hepatosomatic index (HSI), as well as protein and energy retention were not significantly (P>0.05) affected by the dietary treatments. Algal inclusion significantly affected the ADCs of the various dietary treatments for dry matter, CP, and energy. The inclusion of ash in the form of diatomaceous earth improved digestibility of protein as well as weight gain, survival and FE. A second feeding trial evaluated LEA derived from Chlorella sp. processed at high temperatures, replacing 5, 10, 20, and 25% of the CP in the reference diet. Weight gain, FE, survival, and protein efficiency ratio (PER) were significantly reduced at substitution levels of 20 and 25%. The third feeding trial evaluated LEA derived from Nanochloropsis salina, replacing 5, 7.5, 10, and 15% of the CP in the reference diet. Weight gain, FE, survival, and PER were significantly affected by some dietary treatments, with the 15% substitution levels causing significant reductions in performance. Intraperitoneal fat ratio and whole-body lipids were significantly lower in the fish fed the 15% substitution diet. Based on the results of these experiments, replacement of up to 10% of CP from fishmeal and soy protein concentrate with LEA was possible without causing substantial reductions in fish performance, and the whole algae product provided a more nutritious product. Red drum and HSB showed similar responses in their ability to digest CP and energy from the various algal products, although ADCs varied greatly among the different products and processing methods.
56

Interference in White Bass Reproduction by Two Introduced Predators in Barren River Lake, Kentucky

Fose, Jacob Franklin 01 December 2013 (has links)
White bass Morone chrysops are native to the Mississippi River and its tributaries. This range includes the Barren River in south central Kentucky. Over the last thirty years, the population of white bass in Barren River Lake, a reservoir of the Barren River, has been in decline. During that same time, two congeners of white bass have been introduced to the lake. Hybrid striped bass Morone chrysops × Morone saxatilis were introduced in 1979 and yellow bass Morone mississippiensis were first discovered in 2000. Due to the similar life histories and spawning strategies of all three Morone species, I hypothesized that the two introduced species are interfering with reproduction of the native white bass. In the springs of 2012 and 2013 I sampled fish from within a five kilometer stretch of Barren River upstream of the lake. I collected 144 white bass, 111 yellow bass and 29 hybrid striped bass. Detection of species at spawning sites was staggered with yellow bass and hybrid striped bass arriving after white bass but leading to a period of co-occurrence. White bass on the spawning sites appeared healthy: fecundity (75,200 to 741,150 eggs per female), mean gonadosomatic indices (peaked at 10.7% and 23.7% in sequential years), mean relative weight (93.8), and length at age (above the 50th percentile). Of the yellow bass stomachs examined, 21.6% contained fish eggs or larval fish. Based on arrival times and evidence of egg and larval fish predation, it is likely that yellow bass are directly impacting white bass spawning success through reproductive interference and the consumption of white bass offspring. Schoener’s index values revealed a significant degree of dietary overlap between white bass and yellow bass in larval fish, post larval fish, and arthropods (Cxy = 0.992,0.994, and 0.804, respectively), and between white bass and hybrid striped bass in arthropods (Cxy = 0.851). Information from this study may elucidate causes of the declining white bass population and aid in its management in Barren River Lake.
57

Interactions among hybrid striped bass, white bass, and walleye in Harlan County Reservoir

Olson, Nathan William. January 2004 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2004. / Typescript. Chairperson, Graduate Committee: Christopher S. Guy. Includes bibliographical references (leaves 41-48).
58

Occupancy modeling of forest carnivores in Missouri

Hackett, Harvey Mundy, January 2008 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on June 8, 2009) Vita. Includes bibliographical references.
59

An Evaluation of Chemical, Biological, and Combined Chemical-Biological Approaches for Controlling Snails in Aquaculture Ponds

Noatch, Matthew R. 01 May 2010 (has links)
Digenetic trematodes are a common pest problem in aquaculture where their unappetizing appearance often reduces the marketability of food fish. Aquatic snails are intermediate hosts in the trematode lifecycle and are commonly targeted with control measures to prevent the crop fish from becoming infected. I evaluated several chemical and biological snail control strategies as alternatives to the potentially invasive black carp. Copper sulfate, hydrated lime slurry, and several fish and decapod species were tested for effectiveness against physid (Physa spp.) and planorbid (Helisoma spp.) snails in laboratory aquaria trials. Hydrated lime demonstrated effectiveness with the least potential to be toxic to cultured fish in regional application. Hybrid sunfish (redear × green sunfish) consumed large quantities of both snails in ad libitum feedings. The most effective biological (redear × green sunfish) and chemical (hydrated lime) control methods identified in the laboratory were evaluated further in research ponds. Hydrated lime applications of 9.07 kg over 9.14 m2 were found to be effective against Helisoma spp. confined to enclosures along the pond shoreline; average survival was 2%. When stocked in aquaculture ponds, hybrid redear sunfish did not significantly influence snail capture rates; however ponds stocked with redear sunfish experienced a gradual decrease in snail populations throughout the 2008 growing season. Hydrated lime and a combination of redear sunfish and hybrid redear sunfish were evaluated separately and in tandem as a combined chemical/biological treatment in the 2009 growing season. Evaluation occurred under mock production conditions in which hybrid striped bass were raised in the research ponds to determine snail treatment effects on trematode abundance. Ponds stocked with sunfish at 494 fish/ha had snail densities significantly (P ≤ 0.05) lower than control ponds after two months. Ponds treated with hydrated lime at 31.7 kg/31.5 m of shoreline in a 1 m swath experienced 99% estimated reductions in snail densities following application, but snail populations rebounded to previous levels within two months. The mean snail density in ponds treated with both hydrated lime and sunfish was significantly lower than control one month post treatment; this mean rebounded slightly by the conclusion of the trial, but not as much as in the chemical treatment group. Hybrid striped bass examined thoroughly for trematodes revealed a positive relationship between trematode abundance in fish and increasing Helisoma densities. This relationship was most apparent when estimates of snail density from only the beginning of the trial were used. Based on these results, it appears that a nearly complete reduction of Helisoma, particularly at the time of stocking fingerlings, is necessary to avoid a high abundance of trematodes in cultured fish. To this end, an early-season application of molluscicides followed closely by stocking of predator sunfish has potential to achieve a uniformly low density of snails throughout the growing season.
60

EXPLORING SOY-DERIVED ALTERNATIVES TO FISH MEAL: USING SOY PROTEIN CONCENTRATE AND SOY PROTEIN ISOLATE IN HYBRID STRIPED BASS (Morone chrysops ♂ x M. saxatilis ♀) AQUACULTURE

Blaufuss, Patrick 01 December 2010 (has links)
Many sources of protein have been investigated to reduce the use of fish meal (FM) in aquaculture feeds, including soybean meal (SBM). However, FM replacement in feeds for carnivorous species is limited by problems with feed intake, growth rate, and overall health associated with reduced digestibility and anti-nutritional factors found in SBM. However, soy processing strategies can reduce the effects of anti-nutritional factors and improve utilization. Therefore, we examined the possibility of further FM replacement in SBM maximized feeds for hybrid striped bass using refined soy products, soy protein concentrate (SPC) and soy protein isolate (SPI). Results indicate that further FM sparing is possible, beyond what can be achieved with SBM. For example, it is possible to reduce dietary FM content as low as 5% using SPC, and though this negatively affects growth rate, this effect may be reversed by the addition of a betaine-based attractant. Replacement with SPI resulted in such a degree of feeding reluctance that starvation and cannibalization became issues during the trial. Reducing FM content below 5-10% resulted in more variable production performance and, when using SPI, increased incidence of cannibalism. No differences in stress tolerance were observed during the trials; however, there was a trend of increasing handling mortality in fish fed the SPC diets. Refined soy proteins can be used in conjunction with SBM to spare FM, but the cost of these products, along with their acceptability to aquatic livestock, will determine the extent of their utilization in aquafeeds.

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