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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.
1

The effects of Common Carp (Cyprinus carpio L.) on water quality, algae and submerged vegetation in Delta Marsh, Manitoba

Hertam, Susan 21 September 2010 (has links)
Common Carp, (Cyprinus carpio), have long been associated with the degradation of wetlands worldwide. Through their feeding activities they resuspend sediments leading to reductions in the abundance and diversity of submerged macrophytes, and the alteration of water chemistry which can lead to the phytoplankton-dominated state. This study took in Delta Marsh, a freshwater coastal wetland of Lake Manitoba, in Manitoba, Canada. It was the second part of a four-year study in which baseline data were collected in 2001 from ten ponds (1-13 ha) with varying degrees of connectivity to the main marsh and carp-accessibility. I continued to monitor a subset of the control and altered ponds two and three years following their alteration (2003 and 2004); I included new ponds, including one large open bay (20.3 ha). The overall four-year study has shown that the presence of carp is at least partially responsible for the turbid, phytoplankton-dominated state that exists in Delta Marsh, and that carp abundance is an important factor. Ponds previously isolated then exposed to carp activity, particularly in the spring when they were gathered at high densities, shifted to the turbid, phytoplankton-dominated state with few macrophytes, and the removal of carp from ponds led to the clear-water state, though not necessarily an abundance of macrophytes. Due to the complexity of natural ecosystems, the effects of carp were not as predictable as smaller-scale studies would suggest. In my study, water quality, submerged vegetation biomass and algal growth varied both temporally and spatially in carp-accessible and carp-free ponds. Nutrient deficiency among periphyton assemblages was hypothesized to be alleviated by the presence of carp. Using nutrient diffusing substrata, I found that nutrient deficiencies varied from year to year among carp-free and carp-accessible ponds. In 2003 the hypothesis was supported, however, in 2004 two of the carp-free ponds exhibited no-nutrient limitations to periphyton assemblages while N and P co-limitation became prevalent in one carp-accessible pond. Parameters over which there was no control, such as the spatial and temporal distribution of carp, their density within a pond, water depth and unquantified top-down effects, including zooplankton grazing, may have contributed to the variability of the results.
2

The effects of Common Carp (Cyprinus carpio L.) on water quality, algae and submerged vegetation in Delta Marsh, Manitoba

Hertam, Susan 21 September 2010 (has links)
Common Carp, (Cyprinus carpio), have long been associated with the degradation of wetlands worldwide. Through their feeding activities they resuspend sediments leading to reductions in the abundance and diversity of submerged macrophytes, and the alteration of water chemistry which can lead to the phytoplankton-dominated state. This study took in Delta Marsh, a freshwater coastal wetland of Lake Manitoba, in Manitoba, Canada. It was the second part of a four-year study in which baseline data were collected in 2001 from ten ponds (1-13 ha) with varying degrees of connectivity to the main marsh and carp-accessibility. I continued to monitor a subset of the control and altered ponds two and three years following their alteration (2003 and 2004); I included new ponds, including one large open bay (20.3 ha). The overall four-year study has shown that the presence of carp is at least partially responsible for the turbid, phytoplankton-dominated state that exists in Delta Marsh, and that carp abundance is an important factor. Ponds previously isolated then exposed to carp activity, particularly in the spring when they were gathered at high densities, shifted to the turbid, phytoplankton-dominated state with few macrophytes, and the removal of carp from ponds led to the clear-water state, though not necessarily an abundance of macrophytes. Due to the complexity of natural ecosystems, the effects of carp were not as predictable as smaller-scale studies would suggest. In my study, water quality, submerged vegetation biomass and algal growth varied both temporally and spatially in carp-accessible and carp-free ponds. Nutrient deficiency among periphyton assemblages was hypothesized to be alleviated by the presence of carp. Using nutrient diffusing substrata, I found that nutrient deficiencies varied from year to year among carp-free and carp-accessible ponds. In 2003 the hypothesis was supported, however, in 2004 two of the carp-free ponds exhibited no-nutrient limitations to periphyton assemblages while N and P co-limitation became prevalent in one carp-accessible pond. Parameters over which there was no control, such as the spatial and temporal distribution of carp, their density within a pond, water depth and unquantified top-down effects, including zooplankton grazing, may have contributed to the variability of the results.
3

An examination of environmental policy regarding the 2008 Koi Herpesvirus (CyHV-3) outbreak in Lake Simcoe, Ontario, Canada: the disposal of Cyprinus carpio carpio L. on First Nation and off-reserve land

Cooper, Kira Jade 02 May 2013 (has links)
Koi Herpesvirus (KHV), a species-specific DNA virus of the family Herpesviridae, is responsible for mass mortalities of common carp (Cyprinus carpio carpio L.) throughout the world. KHV’s broad geographical distribution and relatively high mortality rate among infected fish, creates significant disposal issues when die-offs occur, especially taking into account the body burden of contaminants in the fish. In locales where adequate disposal facilities are unavailable, or are unable to accommodate additional loadings of contaminated fish carcasses, concerns regarding human and environmental health are raised. During the summer of 2008, residents of the Lake Simcoe Region of southern Ontario, Canada, were faced with a massive die-off of carp, infected with KHV. Carp within the Great Lakes and much of the world are known to bioaccumulate (and biomagnify) contaminants, such as, polychlorinated biphenyls (PCBs), pesticides (e.g., dichlorodiphenyltrichloroethane, DDT, and toxic metals (e.g., mercury). These contaminants have been associated with numerous adverse effects on both human and environmental health, and are thus of important considerations when planning for large-scale carcass disposal, following fish die-offs. Although suites of microbiological tests and water quality assessments are frequently conducted to identify causative factors during extensive fish-kills - assessments of relative contaminant burdens in the carcasses, which should dictate the most appropriate method of carcass disposal - are rarely performed. A case study on Snake Island, Lake Simcoe, Ontario was conducted to further examine the implications of this policy. Soil samples from two known disposal sites and three presumed control locations were sampled on Snake Island and sent to the Analytical Services Unit of Queen’s University for chemical analysis. Although none of the soil samples exceeded any legal guidelines in the present study, there is still concern as future die-offs of other fish species or piscivorous birds and the disposal of large numbers of carcasses may be an issue.
4

An examination of environmental policy regarding the 2008 Koi Herpesvirus (CyHV-3) outbreak in Lake Simcoe, Ontario, Canada: the disposal of Cyprinus carpio carpio L. on First Nation and off-reserve land

Cooper, Kira Jade 02 May 2013 (has links)
Koi Herpesvirus (KHV), a species-specific DNA virus of the family Herpesviridae, is responsible for mass mortalities of common carp (Cyprinus carpio carpio L.) throughout the world. KHV’s broad geographical distribution and relatively high mortality rate among infected fish, creates significant disposal issues when die-offs occur, especially taking into account the body burden of contaminants in the fish. In locales where adequate disposal facilities are unavailable, or are unable to accommodate additional loadings of contaminated fish carcasses, concerns regarding human and environmental health are raised. During the summer of 2008, residents of the Lake Simcoe Region of southern Ontario, Canada, were faced with a massive die-off of carp, infected with KHV. Carp within the Great Lakes and much of the world are known to bioaccumulate (and biomagnify) contaminants, such as, polychlorinated biphenyls (PCBs), pesticides (e.g., dichlorodiphenyltrichloroethane, DDT, and toxic metals (e.g., mercury). These contaminants have been associated with numerous adverse effects on both human and environmental health, and are thus of important considerations when planning for large-scale carcass disposal, following fish die-offs. Although suites of microbiological tests and water quality assessments are frequently conducted to identify causative factors during extensive fish-kills - assessments of relative contaminant burdens in the carcasses, which should dictate the most appropriate method of carcass disposal - are rarely performed. A case study on Snake Island, Lake Simcoe, Ontario was conducted to further examine the implications of this policy. Soil samples from two known disposal sites and three presumed control locations were sampled on Snake Island and sent to the Analytical Services Unit of Queen’s University for chemical analysis. Although none of the soil samples exceeded any legal guidelines in the present study, there is still concern as future die-offs of other fish species or piscivorous birds and the disposal of large numbers of carcasses may be an issue.
5

Evaluation of a Common Carp (Cyprinus carpio L.) Exclusion and Trapping Device for Use in Aquatic Plant Founder Colony Establishment

Williams, Paul Edwin 05 1900 (has links)
The focus of this study was to design and evaluate a trapping system that would reduce populations of common carp within water bodies in conjunction with establishment of native aquatic macrophytes founder colonies. A pond study and field study were conducted. A pond study was performed at the Lewisville Aquatic Ecosystem Research Facility, located in Lewisville, Texas, followed by a field study within a constructed wetland located in southern Dallas, Texas. For the pond study, twelve funnel traps were constructed (four reps of each type: control, dual-walled and ring cage). Two anti-escape devices were tested with funnels including steel fingers and hinged flaps. Ring cage and dual-walled treatments were planted using native pondweeds, while controls were left unplanted (additional bait and a drift fence scenarios were also tested). Common carp were introduced into the study pond. Chi-square statistical analyses were utilized and showed ring cage treatments using fingers as well as the use of a drift fence to be most effective. Following completion of the pond study, the two most effective treatments (controls and ring cages) were tested within the Dallas, Texas wetland; no carp were caught during the field test.
6

Možnosti ovlivňování textury masa kapra obecného (Cyprinus carpio) / Posibilities affecting of texture of common carp(Cyprinus carpio)

JOHÁNEK, Martin January 2011 (has links)
The diploma thesis deals with statistical comparison of the textural properties of common carp (Cyprinus carpio) ? (hardness, springiness, cohesiveness, chewiness) were kept during the experiment at store?ponds in Trebon. Carps in each pond were fed with triticale or modified form of triticale (not processed, pressed, crushed, not processed cooked at 120 °C and 100 °C and pressed at 120 °C) and one control pond with fish. After the experiment the fish were killed, and the recovery factor was esteblished. The fillets were obtained from samples of muscle precisely in a defined way, and property values texture by TPA (Texture profile analyst) was found. The results show that all four monitored mechanical properties of textures, reach the highest values of control (hardness: 4,756 kg, springiness: 0.689, cohesiveness: 0.788 and chewiness: 2,585 kg), and the lowest textural properties were observed in triticale, not processed, heat- prepared at 120 °C: hardness: 3,259 kg, springiness: 0.646 and chewiness: 1,579 kg, and cohesiveness was lowest in triticale not processed cooked at 120°C: 0.733. Only samples pressed at 120 °C and not processed triticale were statistically significanty different from the others in parameter of hardness. Triticale pressed at 120 °C were statisticanty different from not processed, pressed triticale and control in parameter of cohesiveness. Triticale samples pressed at 120 °C and not processed at 120 °C significantly were different from the others and triticale pressed from controlwere diferrent too. In springiness parameter, there was no statistically significant difference. Was used significancy level p=0.01.
7

Obtenção de gelatina utilizando cabeças de carpa comum (Cyprinus carpio): avaliação das etapas de pré-tratamento e extração

Silva, Roberto de Souza Gomes da January 2010 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2010. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-08-19T20:28:05Z No. of bitstreams: 1 dissertao final - roberto.pdf: 715516 bytes, checksum: d89b1ff4b6ead9c473bb17918962a715 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-09-22T18:30:58Z (GMT) No. of bitstreams: 1 dissertao final - roberto.pdf: 715516 bytes, checksum: d89b1ff4b6ead9c473bb17918962a715 (MD5) / Made available in DSpace on 2012-09-22T18:30:58Z (GMT). No. of bitstreams: 1 dissertao final - roberto.pdf: 715516 bytes, checksum: d89b1ff4b6ead9c473bb17918962a715 (MD5) Previous issue date: 2010 / A carpa comum (Cyprinus carpio) é conhecida por ser geradora de quantidade considerável de rejeitos mal aproveitados por indústrias pesqueiras. Estes rejeitos são constituídos por vísceras, peles, ossos e cabeças. Diversos fatores têm contribuído para a utilização de cabeças de carpa provenientes da industrialização, dentre estes a quantidade de cabeças desperdiçadas, que pode atingir 22% do volume da matériaprima, e é uma fonte de nutrientes de baixo custo e rica em colágeno. A maioria das gelatinas comerciais é derivada de mamíferos, sendo peles e ossos de bovinos e suínos as principais matérias-primas do produto. A gelatina é de uma proteína pura, digestível, que se obtém a partir da hidrólise à quente do colágeno, e por este motivo, o pescado torna-se uma potencial fonte de matéria-prima. A aplicação da gelatina é diversificada, podendo ser utilizada na indústria cosmética, farmacêutica,fotográfica e alimentícia. O presente estudo foi dividido em dois objetivos. Primeiramente foram avaliados os efeitos da concentração alcalina, tempo de pré-tratamento e prétratamentos com ou sem troca de solução alcalina do material para a obtenção de gelatina das peles das cabeças de carpa. Foi utilizado um planejamento fatorial 23 completo, e os fatores de estudo foram concentração de NaOH (3-4 M), tempo de prétratamento(45-105 min), e troca de solução de NaOH no pré-tratamento, tendo como respostas rendimento em gelatina, força do gel e ponto de fusão. Na segunda etapa, os ossos remanescentes deste processo foram utilizados para o estudo da influência da granulometria (1-2 mm) nas respostas consideradas das gelatinas extraídas da fração óssea, através da comparação das médias pela aplicação do teste de Tukey, com intervalo de 95% de confiança. Foram realizadas quatro extrações com pH e temperaturas de cada extração de 5,3-60°C, 4,4-70°C, 3,8-80°C e 3,6-85°C. Para as gelatinas extraídas das peles, o maior rendimento (2,27%) foi obtido com solução de NaOH 3 M, 45 min e sem troca de solução no pré-tratamento. Os maiores valores de força do gel (298,7 g) e ponto de fusão (29°C) foram obtidos a concentração de solução NaOH 3 M, 45 min e sem troca de solução alcalina. Para as gelatinas extraídas dos ossos, o maior rendimento (4,86%) foi obtido na granulometria de 1 mm. Os maiores valores de força do gel (128,2 e 131,5 g) não apresentaram diferença significativa (p≤0,05) e foram encontrados na primeira extração das granulometrias de 1 e 2 mm, respectivamente. Na fração óssea a 2 mm, se obteve o maior ponto de fusão, sendo 28,5°C na a primeira extração. O rendimento total da gelatina obtida a partir das cabeças de carpa foi de 7,13%. / Common carp (Cyprinus carpio) is known to produce large amount of byproduct does not made use for fisheries industries. These byproduct can be viscera, skin, bone and head, all riches in collagen. Several factors have been contributing to the use of the carp head coming from industrialization, among which the amount of carp head wasted, with which it can reach around 22% of the volume of the raw material, and it is a source of low costs nutrients. Most of commercial gelatin is derived from mammalian, being skins and bones of bovine and porcine the main raw material of this foodstuff. Gelatin is a pure and digestible protein, which is obtained from hydrolysis of the collagen, and for this reason, the fish become a potential source from raw material. Its application is branched out, being able to used in the cosmetic, pharmaceutical, photographic and food industries. The present study was divided into two parts. At first, it was valued the effect of alkaline concentration, pre-treatment time of the raw material, and treatment with and without change of alkaline solution, in the process of extraction of skin/muscles fraction gelatin of carp head coming from manufacturing processing of this fish. It was used 23 complete experimental design. Pre-treatment time (45-105 min), concentration of alkaline solution (3-4 M) and pre-treatment with change of alkaline solution were chosen as independent variable. Gelatin yield, gel strength and melting point were the response variable. At the second part, was valued of the influence of the bones granulometry (1-2 mm), remaining of the skin extraction of common carp head, in the gelatin yield, gel strength and melting point through the average results comparison by the Tukey test, where differences were considered significant at p≤0.05. It was used four extraction with pH and temperature of each extraction 5.3-60°C, 4.4-70°C, 3.8-80°C and 3.6-85°C. To the skin gelatin the higher gelatin yield (2.27%) was obtained with NaOH solution 3 M, 45 min and pre-treatment without change of alkaline solution. The higher gel strength (298.7 g) was achieved using NaOH solution 3 M, 105 min and pre-treatment without change of the alkaline solution. As for the melting point, the higher value (29.1°C) was obtained with NaOH solution 4 M, 45 min, and pre-treatment with change of NaOH solution. To the bones extraction, the higher gelatin yield was reached with size 1 mm (4.86%). The higher gel strength (128.2 and 131.5 g) were not significantly difference, and they were found in the first extraction with bones size 1 and 2 mm, respectively. Using 2 mm of granulometry, it was possible to obtain the higher melting point values, being 28.5°C to the first extraction.
8

Communal or separate rearing of families in selective breeding of common carp (Cyprinus carpio L.)

Ninh, Nguyen Huu January 2009 (has links)
This study reports on investigation of ways of improving the breeding programme for growth-related traits in common carp in Vietnam. The base population was synthesized following a single pair mating scheme from six carp stocks: (1) 2nd generation of family selection; (2) Hungarian 6th generation of mass selection; (3) Hungarian scaled carp; (4) Indonesian yellow 6th generation of mass selection; (5) Indonesian yellow carp; and (6) Vietnamese 6th generation of mass selection. The next two selected generations were produced using a partial factorial mating scheme, with each family being split and reared using communal early rearing (CER) or separate early rearing (SER) methods. The second generation (G2) was produced from selected fish from the CER G1 group. The total number of selection, control and reference families was 135 in the G1 and 101 in the G2 respectively. The control and reference (Hungarian P33 line) families were produced by single pair mating (reference families with the G2 only). Seven microsatellite loci were used for parentage assignment in the CER groups: 96.8% of the offspring (1284 individuals) and 96.2% offspring (1341 individuals) were unambiguously assigned to 113 families (selection, control) in the G1 and 99 families (selection, control and reference) in the G2 generations, respectively. Restricted maximum likelihood in the individual model was used to estimate phenotypic and genetic parameters. In CER, the estimated heritability values of common carp were from 0.20 ± 0.04 to 0.29 ± 0.05 for both weight and length at final harvest, indicating substantial additive genetic variation for selection on growth-related traits. The overall obtained maternal and common environmental effects were consistently close to zero. The average of direct response to selection for body weight was 15.0% per generation. In SER, the number of families in the G1 and G2 were 135 (selection and control) and 101 (selection, control and reference), respectively. The heritability estimates were from 0.20 ± 0.07 to 0.31 ± 0.08 at final measurement. Common environmental (full-sib family) effect were all lower at tagging and slightly higher at last measurement, ranging from 0.05 to 0.22. The response in each generation of selection as the difference between the selection and control lines was 8.1% on average for weight at final harvest, lower than under CER. The high genetic correlations of growth-related traits between the third (one year old, mature) and second (7 months old) measurements could allow selection to be based on the earlier assessment, reducing handling stress close to spawning. The benefits of using microsatellite markers to ascertain parentage, achieve greater growth rate (close to farming systems), shorten time to maturity and selection, and the overall relative merits of using CER v’s SER in this genetic improvement programme are discussed.
9

Vertikální distribuce zoobentosu v rybníce v reakci na biomasu obsádky kapra / The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds

VÁLEK, Pavel January 2019 (has links)
The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds was tested in the Rod, Dobrá Vůle, Pohořelec, Haslauerteich and Neuteich ponds. Except for the Rod pond, various carp biomass was represented in all ponds. Sampling was conducted during the growing season (June and July), and outside the growing season (September). Physico-chemical parameters of water were measured for each sample. All samples were sorted by groups, counted and weighed. The results are presented in graphs. Zoobenthos density of the Dobrá Vůle, Haslauerteich and Neuteich ponds showed a rising tendency towards deeper parts of the pond sediment. The density of these ponds reached the maximum values in depths of 10-14 cm. This tendency was observed in the occurrence of midges in these ponds. The highest density of midges was observed in the Haslauerteich pond (1,687 individuals per square metre). The above-mentioned ponds were stocked by the common carp (K2-3). The largest density of the tubifexes in the Dobrá Vůle, Haslauerteich and Neuteich ponds was observed during the September sampling in the shallow parts of the sediment (0-6 cm). The maximum density was 1,031 individuals per square metre. On the Pohořelec pond, the occurrence of zoobenthos during both samplings was recorded only in the depth of 10-12 cm. Other representatives of zoobenthos were present in the Rod, Haslauerteich and Neuteich ponds. Larvae of Sialis and Chaoboridae were observed as well. The density and biomass was greater in the September sampling. We have noticed a greater settlement in various depths. Their maximum density was in the Haslauerteich pond (218 individuals per square metre).
10

Vertikální distribuce zoobentosu v rybníce v reakci na biomasu obsádky kapra / The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds

VÁLEK, Pavel January 2016 (has links)
The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds was tested in the Rod, Dobrá Vůle, Pohořelec, Haslauerteich and Neuteich ponds. Except for the Rod pond, various carp biomass was represented in all ponds. Sampling was conducted during the growing season (June and July), and outside the growing season (September). Physico-chemical parameters of water were measured for each sample. All samples were sorted by groups, counted and weighed. The results are presented in graphs. Zoobenthos density of the Dobrá Vůle, Haslauerteich and Neuteich ponds showed a rising tendency towards deeper parts of the pond sediment. The density of these ponds reached the maximum values in depths of 10-14 cm. This tendency was observed in the occurrence of midges in these ponds. The highest density of midges was observed in the Haslauerteich pond (1,687 individuals per square metre). The above-mentioned ponds were stocked by the common carp (K2-3). The largest density of the tubifexes in the Dobrá Vůle, Haslauerteich and Neuteich ponds was observed during the September sampling in the shallow parts of the sediment (0-6 cm). The maximum density was 1,031 individuals per square metre. On the Pohořelec pond, the occurrence of zoobenthos during both samplings was recorded only in the depth of 10-12 cm. Other representatives of zoobenthos were present in the Rod, Haslauerteich and Neuteich ponds. Larvae of Sialis and Chaoboridae were observed as well. The density and biomass was greater in the September sampling. We have noticed a greater settlement in various depths. Their maximum density was in the Haslauerteich pond (218 individuals per square metre).

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