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2011

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Articles 1 - 30 of 140

Full-Text Articles in Aquaculture and Fisheries

Extruded Aquafeeds Containing Distillers Dried Grains With Solubles: Effects On Extrudate Properties And Processing Behaviour, Kamal Mjoun, Kurt A. Rosentrater Dec 2011

Extruded Aquafeeds Containing Distillers Dried Grains With Solubles: Effects On Extrudate Properties And Processing Behaviour, Kamal Mjoun, Kurt A. Rosentrater

Kurt A. Rosentrater

BACKGROUND: The tremendous supply and low cost of distillers dried grains with solubles (DDGS) make it an attractive feedstuff for aquaculture diets. Also, several studies have shown that DDGS can be successfully fed to various finfish. The objective of this study was to evaluate the effects of inclusion rate of DDGS (0, 250, 500 g kg−1), feed moisture content (350, 450 g kg−1) and die opening area (die A = 18.85 mm2, die B = 3988.45 mm2) on the properties of the extrudates and on processing behaviour using a single-screw extruder.

RESULTS: Increasing the inclusion rate of DDGS ...


Prey Selection By The Northern Watersnake, Nerodia Sipedon, Kyle O' Connell Dec 2011

Prey Selection By The Northern Watersnake, Nerodia Sipedon, Kyle O' Connell

Environmental Studies Undergraduate Student Theses

Prey selection and composition of the northern waternake, Nerodia sipedon was investigated between 8/2010 and 3/2011 by palpation of stomach contents in the field and conducting laboratory trials. 41 snakes were captured, five yielded prey contents. Fish parts, freshwater mussels, and an insect exoskeleton were found. No amphibians were found despite availability at study sites. Snakes in the laboratory underwent 22 trials, feeding on 11 occasions. Snakes fed on an equal number of both fish species, revealing no selection. Further research is needed to determine the rate of digestion of N. sipedon.


Genetic Status Of Isolated Populations Of Colorado River Cutthroat Trout (Oncorhynchus Clarkii Pleuriticus) In The North Fork Little Snake River Drainage, Wyoming, Rachel Van Horne Dec 2011

Genetic Status Of Isolated Populations Of Colorado River Cutthroat Trout (Oncorhynchus Clarkii Pleuriticus) In The North Fork Little Snake River Drainage, Wyoming, Rachel Van Horne

All Graduate Theses and Dissertations

Accidental conservation isolation characterizes a situation when a barrier created for a non-conservation purpose happens to fragment a population that now holds conservation value. This study established baseline genetic structure for the isolated populations of Colorado River cutthroat trout in the North Fork Little Snake River drainage, Wyoming. In many cases of accidental isolation, the populations above the barriers have limited habitat and small population sizes that make them vulnerable to extinction and may hold evolutionary value to the species as a whole. All the isolated populations in the drainage currently have high genetic differentiation among tributaries, low genetic diversity ...


An Assessment Of Sea Scallop Abundance And Distribution In Selected Areas: Georges Bank Closed Area Ii, Southern New England/Long Island, New York Bight And The Delmarva Closed Area, David B. Rudders, William D. Dupaul Nov 2011

An Assessment Of Sea Scallop Abundance And Distribution In Selected Areas: Georges Bank Closed Area Ii, Southern New England/Long Island, New York Bight And The Delmarva Closed Area, David B. Rudders, William D. Dupaul

Reports

No abstract provided.


A Test Method For Optimal Micro-Screen Drum Filter Selection, Eoin Dolan, Ronan Oliver, Niall Murphy, Michael O'Hehir Nov 2011

A Test Method For Optimal Micro-Screen Drum Filter Selection, Eoin Dolan, Ronan Oliver, Niall Murphy, Michael O'Hehir

Other resources

In order to meet increasing demand for seafood worldwide Recirculation Aquaculture Systems (RAS) are frequently used. These systems are susceptible to contamination by waste matter including faecal material in the water. It is imperative that this material is removed from the system. The maintenance of good water quality is a pre-requisite to the success of the operation. Negligence in this area will adversely affect animal growth rates and also the economic performance of the system.

Micro-screen drum filters are a popular solution for the removal of this material (Cripps, Simon J. and Bergheim, Asbjørn., 2000). These screens are nominally rated ...


The Effect Of Highly Unsaturated Fatty Acids (Hufa) On Lake Trout (Salve Linus Namaycush) Alevins Using Artemia Nauplii Enriched With Commercial Emulsions And Dry Diets, Blake J. Snyder Oct 2011

The Effect Of Highly Unsaturated Fatty Acids (Hufa) On Lake Trout (Salve Linus Namaycush) Alevins Using Artemia Nauplii Enriched With Commercial Emulsions And Dry Diets, Blake J. Snyder

Environmental Science and Ecology Theses

Highly unsaturated fatty acids (HUFA) are important nutrients for fish survival, development, and reproduction. Fish oil (PO), rich in HUFA, is the dominant lipid source for first feeds in salmonid aquaculture. To determine if other lipid sources would influence survival, growth, and fatty acid profiles in lake trout (Salvelinus narnaycush) alevins, two 8-week feeding experiments were performed. Diets used in the Artemia Experiment included: diet 1, non-enriched Artemia; diet 2,SELCO-enriched Artemia; diet 3, Super SELCO-enriched Artemia; and diet 4, Bio Vita #0, all of which had significantly different fatty acid compositions. The Fish Oil Replacement Experiment used diets that ...


What Is The Value Of A Sea Turtle?: A Case Study Of The Conservation Ethics Of Sea Turtle Fishermen In The Caribbean Coast Of Nicaragua, Alicia Conte Oct 2011

What Is The Value Of A Sea Turtle?: A Case Study Of The Conservation Ethics Of Sea Turtle Fishermen In The Caribbean Coast Of Nicaragua, Alicia Conte

Independent Study Project (ISP) Collection

The sea turtle populations on the Caribbean Coast of Nicaragua have dramatically decreased as a result of human use and consumption. All species of sea turtles are endangered and at risk of extinction. This is an environmental issue because if sea turtles go extinct, many other plants and animals in marine ecosystems will be negatively impacted by this loss, and the environment will be drastically altered. This is also problematic for locals who depend on this resource for food and as a source of income. Conservation efforts have been initiated by an international NGO, the Wildlife Conservation Society (WCS); however ...


A Study Of Sponge Aquaculture In Jambiani: Is Shallow Farming Feasible?, Sarah Friday Oct 2011

A Study Of Sponge Aquaculture In Jambiani: Is Shallow Farming Feasible?, Sarah Friday

Independent Study Project (ISP) Collection

In the village of Jambiani, Unguja, a Swiss NGO called Marine Cultures has established an experimental sponge farming initiative to improve local employment and support economic development. Currently, the main farming site is only accessible through SCUBA diving. This is consistent with experimental farm sites in other oceanic regions, as most are located in depths of at least five meters with sponges suspended vertically to maximize water flow exposure. Farms located in shallower water may not be conducive to sponge growth due to highly variable environmental conditions; however, no conclusive research has been conducted on this matter (Duckworth 2009). Nonetheless ...


An Assessment Of Icthyofauna And Artisanal Fishing From The Port Of Pedregal In The Golfo De Chiriquí., Kathleen A. Carey Oct 2011

An Assessment Of Icthyofauna And Artisanal Fishing From The Port Of Pedregal In The Golfo De Chiriquí., Kathleen A. Carey

Independent Study Project (ISP) Collection

The artisanal fishery based out of Pedregal, on the Pacific Coast of Panama in the Chiriqui Province was studied to analyze the biodiversity and community structure of the icthyofaunal population and investigate the practices and opinions of the fishermen there. The study area is located in the Gulf of Chiriqui, and is heavily influenced by freshwater runoff from anthropogenically influenced rivers during. This is especially relevant during the rainy season. During two weeks in November, at the end of the rainy season, fishermen from one port in Pedregal were accompanied for the purposes of data collection and interviewing. The data ...


Executive Summary, Cumberland County Foodshed Assessment, Report 1, Barbara Ives Sep 2011

Executive Summary, Cumberland County Foodshed Assessment, Report 1, Barbara Ives

Local Food Systems

Like everyone else in these troubled economic times, Mainers are looking for ways to create jobs that will remain relevant and vital in a global economy, that cannot be outsourced, and that will regenerate rather than exploit our natural resources.

A growing number of people believe that a food system rooted in local farms, fisheries, and food production and distribution enterprises can strengthen Maine’s economy and its communities’ health, thereby increasing revenue and decreasing an expense that is crippling government agencies and individuals alike – healthcare. Business people who want to make a living related to food, and public and ...


Preliminary Analysis Of The Economic Impact Of The H-2b Worker Program On Virginia’S Economy, Thomas J. Murray Sep 2011

Preliminary Analysis Of The Economic Impact Of The H-2b Worker Program On Virginia’S Economy, Thomas J. Murray

Reports

No abstract provided.


Evaluating Recruitment Of American Eel, Anguilla Rostrata, In The Potomac River (Spring 2011), Troy D. Tuckey, Mary C. Fabrizio Sep 2011

Evaluating Recruitment Of American Eel, Anguilla Rostrata, In The Potomac River (Spring 2011), Troy D. Tuckey, Mary C. Fabrizio

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (FMP) for the American eel in November 1999. The FMP focuses on increasing coastal states’ efforts to collect American eel data through both fishery-dependent and fishery-independent studies. Consequently, member jurisdictions agreed to implement an annual survey for young-of-year (YOY) American eels. The survey is intended to “…characterize trends in annual recruitment of the YOY eels over time [to produce a] qualitative appraisal of the annual recruitment of American eel to the U.S. Atlantic Coast” (ASMFC 2000). The development of these surveys began in 2000 with full ...


Interspecies Comparison Of Αii-Spectrin Abundance Between Chinook Salmon And Steelhead, Brielle D. Kemis, Ann L. Miracle, Katie A. Wagner, Christa M. Woodley Aug 2011

Interspecies Comparison Of Αii-Spectrin Abundance Between Chinook Salmon And Steelhead, Brielle D. Kemis, Ann L. Miracle, Katie A. Wagner, Christa M. Woodley

STAR (STEM Teacher and Researcher) Presentations

Salmonids, such as Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss), are a staple economic, recreational, tribal, and environmental resource, yet many populations are unsustainable. This study was part of a broad scale effort to monitor the impact of downstream migration obstacles on juvenile salmonid health and survival, which is an essential step towards increasing Smolt-to-Adult Return ratios (SARs). The objective of this study was to determine if juvenile Chinook salmon and steelhead exhibit differing quantities of alphaII-Spectrin Breakdown Products (SBDPs) over two consecutive spring migration periods, indicative of neurogenesis rate and/or biological response to head injury. AlphaII-Spectrin is ...


Single-Screw Extrusion Modeling Effects On Extrusion Processing Parameters And Physical Properties Of Ddgs-Based Nile Tilapia ( Oreochromis Niloticus ) Feeds, Ferouz Y. Ayadi, Parisa Fallahi, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan Aug 2011

Single-Screw Extrusion Modeling Effects On Extrusion Processing Parameters And Physical Properties Of Ddgs-Based Nile Tilapia ( Oreochromis Niloticus ) Feeds, Ferouz Y. Ayadi, Parisa Fallahi, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan

Kurt A. Rosentrater

A single-screw laboratory extruder was used to conduct an L 18 (2 2 X 3 6 ) Taguchi fractional factorial study of aquafeed processing. The ingredients were based on a formulation for nutritionally-balanced Nile tilapia diets containing distillers dried grains with solubles (DDGS) and soybean meal as the main protein sources, in addition to constant amounts of corn flour, whey, and fish meal. The effects of three levels of DDGS (20, 30 and 40%), soybean meal (30, 40 and 50%), ingredient moisture content (20, 30 and 40% db), screw speed (100, 150 and 200 rpm), barrel temperatures (80-100-100°C, 80-120-120°C ...


Effects Of Conditioner Steam, Extruder Water And Screw Speed On Physical Properties Of Ddgs-Based Extrudates In Twin-Screw Extrusion, Parisa Fallahi, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan, Mehmet Tulbek Aug 2011

Effects Of Conditioner Steam, Extruder Water And Screw Speed On Physical Properties Of Ddgs-Based Extrudates In Twin-Screw Extrusion, Parisa Fallahi, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan, Mehmet Tulbek

Kurt A. Rosentrater

A fractional factorial design with a replicated central composite point was used to investigate the effects of extrusion processing on physical properties of DDGS–based aquafeeds using a twin screw extruder. Extrusion cooking trials were performed using an ingredient blend for Nile tilapia, with 2 levels of screw speed (350 and 450 rpm), 2 levels of extruder water (0.236 and 0.302 kg/min) and 2 levels of conditioner steam (0.1 and 0.15 kg/min). The central point was 400 rpm screw speed, 0.271 kg/min extruder water, and 0.12 kg/min conditioner steam. Effects ...


The Role Of Crassostrea Virginica Hemocytes In Shell Formation: Ex Vivo Mineral Deposition By Cultured Hemocytes, Emily A. Untener, Douglas C. Hansen, Karolyn Hansen Aug 2011

The Role Of Crassostrea Virginica Hemocytes In Shell Formation: Ex Vivo Mineral Deposition By Cultured Hemocytes, Emily A. Untener, Douglas C. Hansen, Karolyn Hansen

Biology Faculty Publications

Abstract of Technical Paper Presented at the 103rd Annual Meeting National Shellfisheries Association Baltimore, Maryland March 27–31, 2011


Abstracts Of Technical Papers Presented At The 103rd Annual Meeting National Shellfisheries Association Baltimore, Maryland March 27–31, 2011, National Shellfisheries Association Aug 2011

Abstracts Of Technical Papers Presented At The 103rd Annual Meeting National Shellfisheries Association Baltimore, Maryland March 27–31, 2011, National Shellfisheries Association

VIMS Articles

No abstract provided.


2011 Annual Report Estimating Relative Juvenile Abundance Of Ecologically Important Finfish In The Virginia Portion Of Chesapeake Bay, Troy D. Tuckey, Mary C. Fabrizio Jul 2011

2011 Annual Report Estimating Relative Juvenile Abundance Of Ecologically Important Finfish In The Virginia Portion Of Chesapeake Bay, Troy D. Tuckey, Mary C. Fabrizio

Reports

No abstract provided.


Mercury In The Pelagic And Benthic Food Webs Of The Great Salt Lake, Wayne A. Wurtsbaugh, Erin Fleming, Caleb Izdepski, Jodi Gardberg Jul 2011

Mercury In The Pelagic And Benthic Food Webs Of The Great Salt Lake, Wayne A. Wurtsbaugh, Erin Fleming, Caleb Izdepski, Jodi Gardberg

Watershed Sciences Faculty Publications

No abstract provided.


The Lobster Bulletin Summer 2011, Lobster Institute Jul 2011

The Lobster Bulletin Summer 2011, Lobster Institute

Lobster Bulletin

In this issue:

Lobster Institute Cooperating Experts Directory a Valuable Asset

Atlantic Lobster Sustainability Foundation Hosts First Lobster Science Symposium

Using the Invasive Green Crab in Food Product Development

Progress in the war against sea lice

Maine Lobster Chef of the Year Finalists to Compete in Portland


Twin-Screw Extrusion Processing Of Rainbow Trout (Oncorhynchus Mykiss) Feeds Using Various Levels Of Corn-Based Distillers Dried Grains With Solubles (Ddgs), Ferouz Y. Ayadi, Kasiviswanathan Muthukumarappan, Kurt A. Rosentrater, Michael L. Brown Jul 2011

Twin-Screw Extrusion Processing Of Rainbow Trout (Oncorhynchus Mykiss) Feeds Using Various Levels Of Corn-Based Distillers Dried Grains With Solubles (Ddgs), Ferouz Y. Ayadi, Kasiviswanathan Muthukumarappan, Kurt A. Rosentrater, Michael L. Brown

Kurt A. Rosentrater

Increasing demand for seafood products and rising demand for fish meal for commercial fish feeds is driving the search for effective alternative protein sources. Twin-screw extrusion trials were conducted to study the production of nutritionally balanced feeds for rainbow trout fingerlings (Oncorhynchus mykiss). Six isocaloric (≈4.61 kcal/g) ingredient blends with a target protein content of >45% db were formulated with 0, 10, 20, 30, 40, and 50% distillers dried grains with solubles (DDGS) and other feed ingredients. The moisture contents of the diets were initially adjusted to 5–7% db, and then extruded at 250 rpm using dual ...


Invertebrate Zooid Polymorphism: Hydractinia Polyclina And Pagurus Longicarpus Interactions Mediated Through Spiralzooids, Charlotte M. Regula-Whitefield Jul 2011

Invertebrate Zooid Polymorphism: Hydractinia Polyclina And Pagurus Longicarpus Interactions Mediated Through Spiralzooids, Charlotte M. Regula-Whitefield

All Theses And Dissertations

Evaluating the net interaction between symbionts can be challenging when one participant is a colonial animal with polymorphic zooids, because each zooid type has unique functions. The colonial hydroid Hydractinia polyclina has three distinct zooid types, each of which contributes particular components to the interaction with host hermit crabs. Of these three zooid types, the function of spiralzooids is not well understood. Previously, spiralzooids have been proposed to contribute a strong negative interaction component by directly reducing their host hermit crab’s reproductive output. However, this hypothesis is not supported by past or current data. I propose that spiralzooids instead ...


Effects Of Dietary Distillers Dried Grains With Solubles And Soybean Meal On Extruded Pellet Characteristics And Growth Responses Of Juvenile Yellow Perch, Travis W. Schaeffer, Michael L. Brown, Kurt A. Rosentrater Jul 2011

Effects Of Dietary Distillers Dried Grains With Solubles And Soybean Meal On Extruded Pellet Characteristics And Growth Responses Of Juvenile Yellow Perch, Travis W. Schaeffer, Michael L. Brown, Kurt A. Rosentrater

Natural Resource Management Faculty Publications

A 126-d feeding trial was performed to investigate graded combinations of distillers dried grains with solubles (DDGS) and soybean meal (SBM) in diets formulated for yellow perch Perca flavescens. Six experimental diets contained DDGS and SBM at 0 and 31.5% (dry matter basis), respectively (0/31.5 diet), 10 and 26% (10/26), 20 and 20.5% (20/20.5), 30 and 15% (30/15), 40 and 9.5% (40/9.5), and 50 and 4% (50/4) to obtain similar levels of crude protein (mean ± SE = 30.1 ± 0.2%), crude lipid (16.7 ± 0.7%), and digestible ...


Twin-Screw Extrusion Processing Of Distillers Dried Grains With Solubles (Ddgs)-Based Yellow Perch (Perca Flavescens) Feeds, Ferouz Y. Ayadi, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan, Michael L. Brown Jul 2011

Twin-Screw Extrusion Processing Of Distillers Dried Grains With Solubles (Ddgs)-Based Yellow Perch (Perca Flavescens) Feeds, Ferouz Y. Ayadi, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan, Michael L. Brown

Natural Resource Management Faculty Publications

Increases in global aquaculture production, compounded with limited availabilities of fish meal for fish feed, has created the need for alternative protein sources. Twinscrew extrusion studies were performed to investigate the production of nutritionally balanced feeds for juvenile yellow perch (Perca flavescens). Five isocaloric (~3.06 kcal/g) ingredient blends, adjusted to a target protein content of 36.7% db, were formulated with 0%, 10%, 20%, 30%, and 40% distillers dried grains with solubles (DDGS) at an initial moisture content of 5–7%db, with appropriate amounts of fish meal, fish oil, whole wheat flour, corn gluten meal, and vitamin ...


Determinants Of Local And Migratory Movements Of Great Lakes Double-Crested Cormorants, Alban Guillaumet, Brian S. Dorr, Guiming Wang, Jimmy D. Taylor Ii, Richard B. Chipman, Heidi Scherr, Jeff Bowman, Kenneth F. Abraham, Terry J. Doyle, Elizabeth Cranker Jun 2011

Determinants Of Local And Migratory Movements Of Great Lakes Double-Crested Cormorants, Alban Guillaumet, Brian S. Dorr, Guiming Wang, Jimmy D. Taylor Ii, Richard B. Chipman, Heidi Scherr, Jeff Bowman, Kenneth F. Abraham, Terry J. Doyle, Elizabeth Cranker

Brian S Dorr

We investigated how individual strategies combine with demographic and ecological factors to determine local and migratory movements in the double-crested cormorants (Phalacrocorax auritus). One hundred and forty-five cormorants were captured from 14 nesting colonies across the Great Lakes area and fitted with satellite transmitters. We first tested the hypotheses that sexual segregation, density-dependent effects, and the intensity of management operations influenced home range size during the breeding season. The influence of these factors appeared to be limited in part due to random variability in foraging and dispersal decisions at individual and colony levels. We also designed a statistical framework to ...


Results For The 2010 Vims/Industry Cooperative Surveys Of Georges Bank Closed Area I And The Hudson Canyon Closed Area, David B. Rudders, William D. Dupaul Jun 2011

Results For The 2010 Vims/Industry Cooperative Surveys Of Georges Bank Closed Area I And The Hudson Canyon Closed Area, David B. Rudders, William D. Dupaul

Reports

No abstract provided.


Results For The 2011 Vims/Industry Cooperative Survey Of Georges Bank Closed Area Ii, William D. Dupaul, David B. Rudders Jun 2011

Results For The 2011 Vims/Industry Cooperative Survey Of Georges Bank Closed Area Ii, William D. Dupaul, David B. Rudders

Reports

No abstract provided.


अंत:स्थलीय मात्स्यिकी - उत्पादन एवं संसाधन प्रबंधन (Inland Fisheries -Production And Resource Management), A. P. Sharma, M. K. Bhandhopadhyay, Ganesh Chandra, A. Roy Jun 2011

अंत:स्थलीय मात्स्यिकी - उत्पादन एवं संसाधन प्रबंधन (Inland Fisheries -Production And Resource Management), A. P. Sharma, M. K. Bhandhopadhyay, Ganesh Chandra, A. Roy

Ganesh Chandra

No abstract provided.


Rna Interference In Marine And Freshwater Sponges: Actin Knockdown In Tethya Wilhelma And Ephydatia Muelleri By Ingested Dsrna Expressing Bacteria, Ajna S. Rivera, April L. Hill, Et. Al. Jun 2011

Rna Interference In Marine And Freshwater Sponges: Actin Knockdown In Tethya Wilhelma And Ephydatia Muelleri By Ingested Dsrna Expressing Bacteria, Ajna S. Rivera, April L. Hill, Et. Al.

Biology Faculty Publications

Background: The marine sponge Tethya wilhelma and the freshwater sponge Ephydatia muelleri are emerging model organisms to study evolution, gene regulation, development, and physiology in non-bilaterian animal systems. Thus far, functional methods (i.e., loss or gain of function) for these organisms have not been available.

Results: We show that soaking developing freshwater sponges in double-stranded RNA and/or feeding marine and freshwater sponges bacteria expressing double-stranded RNA can lead to RNA interference and reduction of targeted transcript levels. These methods, first utilized in C. elegans, have been adapted for the development and feeding style of easily cultured marine and ...


Annual Report Data Collection And Analysis In Support Of Single And Multispecies Stock Assessments In Chesapeake Bay: The Chesapeake Bay Multispecies Monitoring And Assessment Program, Christopher F. Bonzek, James Gartland, Robert J. Latour Jun 2011

Annual Report Data Collection And Analysis In Support Of Single And Multispecies Stock Assessments In Chesapeake Bay: The Chesapeake Bay Multispecies Monitoring And Assessment Program, Christopher F. Bonzek, James Gartland, Robert J. Latour

Reports

Historically, fisheries management has been based on the results of single‐species stock assessment models that focus on the interplay between exploitation level and sustainability. There currently exists a suite of standard and accepted analytical frameworks (e.g., virtual population analysis (VPA), biomass dynamic production modeling, delay difference models, etc.) for assessing the stocks, projecting future stock size, evaluating recovery schedules and rebuilding strategies for overfished stocks, setting allowable catches, and estimating fishing mortality or exploitation rates. A variety of methods also exist to integrate the biological system and the fisheries resource system, thereby enabling the evaluation of alternative management ...