<p>Silver carp (<i>Hypophthalmichthys molitrix</i>)<b> </b>are an underutilized, invasive fish threatening native species throughout major water systems in the United States. The goal of this research was to use silver carp meat to create a value-added product, to analyze the changes in physicochemical structure and consumer liking over time, and to evaluate the benefits of adding soy, pea, and a combination of soy and pea protein isolates to the formulations. Fish nuggets were prepared from minced meat in four treatments consisting of 3% soy protein isolate (SPI), 3% pea protein isolate (PPI), a combination of 1.5% SPI and 1.5% PPI, and a control without plant protein isolate. Nuggets from each treatment were stored frozen for 1.5, 8.5, and 13.5 weeks. Proximate composition, pH, cook loss, textural hardness, expressible moisture, color, microbial counts and lipid oxidation were evaluated. Sensory acceptability was also evaluated for each frozen storage time period and treatment. A descriptive (QDA^™) trained sensory panel was also conducted on all treatments independent of the storage testing. Results showed that lipid oxidation and textural hardness significantly (P < 0.05) increased with frozen storage time. PPI had significantly lower expressible moisture compared to the control at week 1.5, but there were no statistically significant differences between treatments at weeks 8.5 and 13.5. Similarly, formulations with PPI improved (p<0.05) cook loss for week 1.5, but not week 8.5 or 13.5. Overall, sensory acceptability did not change (P > 0.05), with the exception of decreased degree of liking scores for SPI aroma (p=0.03) and flavor (p=0.03)) during the frozen storage period; all degree of liking scores remained above 6.5 throughout analysis, indicating that consumers’ acceptability of the sample treatments over time despite the changes in physicochemical structure. The descriptive panel created an attribute lexicon for the aroma, flavor, and mouthfeel of the fish nuggets and did not find significant differences in intensities for those attributes between the treatments. Although there were measurable changes in oxidation, texture, expressible moisture, and cook loss over 13.5 weeks, these changes did not impact sensory acceptance. The addition of protein isolates improved water holding capacity initially but did not maintain those benefits over extended shelf life and had little impact on consumer liking during any time period. Overall, this study demonstrated that value-added products such as silver carp nuggets can be created using an otherwise under-utilized fish. The fish nuggets had high sensory acceptability, and the addition of protein isolates did not significantly improve their sensory characteristics; therefore, silver carp nuggets can be formulated without the need of additional protein additives .</p>

In Sachsen gewinnt die Aufzucht von Stören in Teichen zunehmend an Bedeutung, insbesondere um die Wirtschaftlichkeit der Warmwasserteichwirtschaft zu verbessern. Mit der Störerzeugung wurden Kapazitäten für die Herstellung von Farmkaviar geschaffen. Dieser ist jedoch starken Qualitätsunterschieden unterworfen. Störe neigen zu einer starken Verfettung des Eingeweidekomplexes, des Filets und der Gonaden, was geschmackliche Probleme zur Folge hat. Es wurde untersucht, ob spezielle Futtermittel, die für die finale Aufzuchtphase von Stören angeboten werden, geeignet sind, die Kaviarqualität zu verbessern und der Verfettung entgegenzuwirken. Mit allen vier geprüften Futtermitteln konnten gute Zuwachsleistungen und eine Verbesserung der Produktqualität erreicht werden. Alle Futtermittel erwiesen sich als geeignet für die Störaufzucht in der finalen Aufzuchtsaison vor der Kaviargewinnung. Die eingesetzten Futtermittel hatten jedoch weder Einfluss auf die zu gewinnende Menge, noch auf die Qualität des Kaviars.

Comparing the protein compositions of three fishes, grass carp exhibited lower band intensity at 47.9 KDa, β-tropomyosin (36.5 KDa), and missed the band at 15.9 KDa myosin light chain. Bigmouth buffalo had a darker tropomodulin (38.8 KDa) band and smaller α-tropomyosin (33-37 KDa) than silver and grass carp. The breaking force (611.8 g) and deformation (11.7 mm) of silver carp cooked gel were significantly higher than the other two fish products. The addition of starches at 2, 4, and 6% to the grass carp paste lowered the breaking force of the cooked gel in a dose-responsive manner compared to the control (P<0.05), but no differences were found in bigmouth buffalo. The bioumulated Murine Norovirus-1 (MNV-1) was found to maintain infectivity during storage of live oysters at 5°C for 15 days while the inoculated MNV-1 kept infectious for 20 days in cooked surimi and salmon fillet. Treatments with 4.0 kGy X-ray achieved the reductions of 3.7 log PFU mL-1 in pure culture or 2.7, 2.2, and 2.0 log PFU g-1 in half-shell oyster, salmon sushi and tuna salad, respectively. X-ray significantly reduced the population of internalized MNV-1 in live oysters from 4.3 ± 0.4 log PFU g-1 to 3.6 ± 0.5, 3.2 ± 0.2, 2.8 ± 0.2, and 2.5 ± 0.1 log PFU g-1, by 1.0, 2.0, 3.0, and 4.0 kGy X-ray, respectively. The population of MNV-1 was reduced to less than 2.0 log PFU g-1 at 5.0 kGy X-ray. The survivability of live oysters was not significantly affected by treatment with 5.0 kGy X-ray, in comparison with the control, for up to 10 days, respectively, during storage at 5°C. Fish sauce was fermented from the by-products of silver carp. The total nitrogen content of fish sauce made in April, and November were 9.86±0.9 and 9.71±4.5 g/l, respectively, which was significantly (p<0.05) higher than the sample of February (8.45±0.25 g/l ), reflecting seasonal effect. The total nitrogen, amino acid nitrogen, pH, and sodium chloride of fish sauce made from silver carp by-products met the international fish sauce standard code of CODEX STAN 302-2011.

No description available.

No description available.

<p>High density sampling (n=50) was conducted in Cootes Paradise, a shallow wetland on the western shoreline of Lake Ontario near the city of Hamilton. Cootes Paradise is an urban wetland that has been affected by pollutants and nutrients and invasive carp. Thecamoebian analyses paired with site specific environmental measurements (depth, sp. conductivity, temperature, DO and pH) and substrate characteristics (textural and organic content -LOI) show relationships (R² = 0.6) with depth (0-1m) and corresponding sp. conductivity (0.5 to 0.65 mS/cm) and temperature (26.5 to 30.5 °C). Q-mode cluster analysis recognized two biofacies. Biofacies 1 samples (n= 26) are found in the deeper areas (0.70 ± 0.27 m) and dominated by <em>C. tricuspis</em> 36 ± 8% (1 std), <em>L. vas</em> 18 ± 13% and <em>D. protaeiformis “claviformis”</em> 14 ± 6%. Mean water temperature is 28.0 ± 0.6 °C and conductivity at 0.56 ± 0.04 mS/cm. This assemblage has low species diversity (SDI=1.9 ± 0.3) which indicates a transitional environment. Biofacies 2 contains samples (n= 24) which are found in shallower areas (0.38 ± 0.15 m) and the assemblage is characterized by <em>C. constricta “aerophila”</em> 25 ± 8%, <em>C. tricuspis</em> 18 ± 5%, <em>Cyclopyxis sp.</em> 9 ± 6 % and <em>L. vas</em> 9 ± 4 %. The SDI for Biofacies 2 is 2.2 ± 0.2 and like Biofacies 1 shows a transitional environment. The average temperature is and 29.0 ± 1.0 °C with mean sp. conductivity also slightly higher than Biofacies 1 at 0.6 ± 0.04 mS/cm.</p> / Master of Science (MSc)

This research investigated hydrologic connectivity, the intricate network of water pathways linking waterbodies, and its implications for biodiversity exchange in floodplains. Chapter 1 provides an exhaustive literature review encompassing factors influencing hydrologic connectivity, assessment approaches, scales, challenges, and management tools. Existing research often focuses on single scales and short-term periods, revealing a need for comprehensive multi-scale and extended temporal analyses. The absence of standardized definitions and methodologies in this field is also considered. Chapter 2 presents an innovative approach quantifying eight key connectivity metrics using remote sensing and GIS within the Lower Mississippi Alluvial Valley (LMAV). This adaptable method assesses connectivity between oxbow lakes and varying stream sizes, revealing spatial variability within the LMAV and enhancing scientific understanding of connectivity dynamics while ensuring portability. This research is crucial for effective ecosystem management and targeted conservation efforts, particularly regarding invasive species like the bigheaded carps (Hypophthalmichthys spp.).

M.Sc. (Environmental Management) / Please refer to full text to view abstract

<p>Cilj istraživanja bio je da se utvrdi u kojoj meri dodavanje lanenog ulja u peletirane krmne<br />smje&scaron;e i ishrana tovnog &scaron;arana tako obogaćenom hranom utječe na količinu masti i<br />kompoziciju masnih kiselina u mesu ribe. Krmne smje&scaron;e u svim grupama istraživanja su bile<br />istog sirovinskog sastava, osim dodatka lanenog ulja koje se menjalo (2,0; 3,0; 4,0; 5,0% i 6%<br />u drugom ogledu) i masti (Magnapac) koja je smanjivana za istu postotnu vrednost dodatkom<br />lanenog ulja. Većim delom istraživanog razdoblja fizičko-hemijski parametri vode su u svim<br />ekspermentalnim ribnjacima varirali u pogodnim vrednostima za uzgoj toplovodnih riba. Udio<br />C18:1 cis-9 statistički je značajno najniži u kontrolnoj grupi i iznosi 35,43%. Povećanjem<br />vrednosti lanenog ulja povećava se i udio C18:1 cis-9. Statistički najvi&scaron;a vrednost C20:0 je kod<br />uzoraka hranjenih s dodatkom 5% lanenog ulja. Najniža vrednost C20:3 &omega;-3 je u kontrolnoj<br />grupi i iznosi 0,22% a značajno najvi&scaron;a u grupi koja se hrani s dodatkom 5% lanenog ulja. S<br />obzirom na dodatak lanenog ulja u hrani, nema značajnih razlika kod ukupnih zasićenih,<br />mononezasićenih, polinezasićenih i omega-6 masnih kiselina. Najveći udio &omega;-3 masnih<br />kiselina utvrđen je u uzorcima &scaron;arana kojima je u hranu dodano 5% lanenog ulja (5,41%) U<br />drugom ogledu utvrđena je opravdanost upotrebe lanenog ulja u hrani za ribe u odnosu na<br />efekte koji su dobijeni u mesu. Omjer &omega;-3/&omega;-6 masnih kiselina značajno se povećao u grupama<br />kojima je u hranu dodat veći dio lanenog ulja (0,21 u kontrolnoj grupi do 0,30% u grupi s<br />dodatkom 5% lanenog ulja). Vrednostiholesterola se nisu značajno menjale dodavanjem<br />lanenog ulja u ishrani &scaron;arana.</p> / <p>The aim of this study was to determine to what extent adding flaxseed oil to pellet diet and<br />fattening carp so enriched food affects the amount of fat and the composition of fatty acids in<br />fish meat. Feed mixtures in all the studied groups were the same composition, except for the<br />addition of linseed oil to be changed (2.0; 3.0; 4.0; 5.0% and 6%) and fat (Magnapac), which<br />was reduced by the same percentage value addition linseed oil. During substantial period of<br />research physico-chemical parameters of water in all experimental ponds ranged in values<br />suitable for the cultivation of warm-water fish. Share C18:1 cis-9 was statistically significantly<br />lowest in the control group and amounted 35.43%. By increasing the value of flaxseed oil<br />increases the proportion of C18:1 cis-9. Statistical highest value of C20:0 in the samples fed<br />with the addition of 5% linseed oil. The lowest value of C20:3 &omega;-3 in the control group is<br />0.22% and significantly highest in the group that feeds supplemented with 5% linseed oil. Due<br />to the addition of linseed oil in the food, there is no significant difference in total saturated,<br />monounsaturated, polyunsaturated omega-6 fatty acids. The largest proportion of &omega;-3 fatty<br />acids found in samples of carp which was in food supplemented with 5% linseed oil (5.41%).<br />The experimental results of the second experiment show the usefulleness of using of linseed oil<br />in fish food regearging the meat quality. The ratio &omega;-3/&omega;-6 fatty acid increased significantly in<br />the group that is added to food in a higher proportion of linseed oil (0.21 in the control group<br />to 0.30% in the group with addition of 5% linseed oil). The value of cholesterol was not<br />significantly changed by adding linseed oil to the diet of carp.<br />Accepted on Senate on:<br />AS</p>

Marine and freshwater aquatic invasive species are a huge problem in the United States and its territorial waters with myriad ecological and economic impacts. Current management methods have fallen short. One possible solution is to harvest them for human consumption. This should be done through small scale, carefully regulated, scientifically based programs that are part of a larger overall management strategy. Four case studies (northern snakehead, European green crab, Asian carp, Chinese mitten crab) assessing edibility are included.