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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.
111

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).
112

Uso de imunoestimulante Saccharomyces cerevesiae em peixes da espécie Cyprinus carpio / Feed with immunostimulant Saccharomyces cerevesiae for fishes of the specie Cyprinus carpio

Viadanna, Pedro Henrique de Oliveira 29 March 2012 (has links)
O aquarismo é uma atividade mundialmente difundida e um segmento extremamente grande da indústria de animais de estimação. O Brasil, em 2007, exportou o valor de US$ 5.871.576,73 em peixes. Devido à biologia dos peixes, todo seu manejo pode desencadear uma resposta fisiológica de estresse, que, dependendo da duração, tipo e espécie de manejo leva a uma resposta imunossupressora, que pode acarretar doença e morte aguda e consequentemente grande prejuízo à produção desses animais. O uso de imunoestimulantes, como suplementação dietética pode prover defesa inata e resistência a patógenos. O presente trabalho teve como objetivo avaliar a viabilidade da utilização de mananoligossacarídeo de levedo de cerveja (Saccharomyces cerevesiae), como imunoestimulante adicionado à ração oferecida a peixes da espécie Cyprinus carpio durante 45 dias. Para avaliar a imunidade dos peixes, foram feitas avaliações hematológicas periódicas e, no final do período determinado, os peixes foram desafiados imunologicamente com estresse e infectados com Aeromonas hydrophila. As carpas do grupo controle tiveram uma taxa de crescimento de 0,05 g/dia, conversão alimentar de 14,09 e eficiência protéica de 0,25, enquanto o grupo imunoestimulado obteve a taxa de crescimento de 0,11g/dia, conversão alimentar de 6,15 e eficiência protéica de 0,57. Não houve diferença estatística entre o resultado da hematologia dos animais do grupo controle e do grupo imunoestimulado. Dos animais infectados experimentalmente, 88% morreram em menos de 24 horas por choque endotóxico e, no exame post mortem, não houve diferença entre os grupos. A carpa que recebeu alimentação controle e foi infectada teve anemia macrocítica normocrômica, trombocitopenia, linfopenia, monocitose e aumento do número de CGE. A carpa que recebeu alimentação com MOS, foi infectada e sobreviveu, não apresentou alteração nos parâmetros hematológicos. A ração com MOS foi zootecnicamente melhor para a nutrição das carpas. Com base na taxa de sobrevivência e na avaliação hematológica, não há como responder se a ração suplementada com MOS foi imunologicamente melhor do que a ração controle. / The aquarium hobby is an activity wordwide spread and a segment extremely large of the pet industry. Brazil, in 2007, exported an amount of US$ 5.871.576,73 of fishes. Due to the biology of the fishes, all its management can trigger a physiological response leading to stress, that depending on the duration, type and specie, can conclude in immunosuppressive response, leading to disease and acute death, creating a great prejudice. The use of immunostimulants, as dietary supplementation may provide an innate defense against pathogens. This study aims to evaluate the feasibility of using mannan oligosaccharide of brewer yeast (Saccharomyces cerevesiae) as immunostimulants added to the feed for koi fishes (Cyprinus carpio) during 45 days. To evaluate the immunity of the fishes, periodic hematologic evaluations were made and at the end of the determined period, the fishes were immunologically challenged with stress and inoculation with Aeromonas hydrophila. The control group had a growth rate of 0,05g/day, feed conversion of 14,09 and protein efficiency ratio of 0,25, while the treatment group had growth rate of 0,11g/day, feed conversion of 6,15 and protein efficiency ratio of 0,57. The hematological results showed no statistical difference between the control group and immunostimulant group according. Analyzing the experimental infected animals, 88% died within 24 hours, due to endotoxic shock, and in the post mortem examination, there were no difference between groups. The koi that received control feed and it was infected had macrocytic normochromic anemia, thrombocytopenia, lymphopenia, monocytosis and increased of special granulocytic cells. The koi that received the MOS feed, was infected with A. hydrophila and survived, had no alteration on haematological parameters. The feed with MOS was zootechnical better than the control feed to carps. Based on the rate of survival and hematology, there are no possibility of answering if supplemented feed with MOS was immunologic better than control feed.
113

The role of carp (Cyprinus carpio L) size in the degradation of freshwater ecosystems.

Driver, Patrick, n/a January 2002 (has links)
Carp (Cyprinus carpio) are alien freshwater fish that are globally widespread and often associated with highly degraded freshwater ecosystems. This study explored carphabitat interactions that could contribute to the worldwide distribution of, and consequent ecological impacts by, carp. Particular emphasis was placed on the role of carp size in these interactions. One component of this study involved a field experiment that was used to quantify the effects of carp biomass density and size-structure on freshwater invertebrate communities and water quality. The treatments in this field experiment comprised different combinations of large (2 kg) and small (0.7 kg) carp, and low (330 kg.ha-1), intermediate (570 kg.ha-1) and high (650 kg.ha-1) biomass densities. Carp impacts were more carp size-dependent than described in previous studies. In particular, carp size was more important than carp biomass density in determining the concentration of total phosphorus and algal biomass. On the other hand, a more even mix of carp sizes increased total nitrogen. The zooplankton and macroinvertebrate taxa that were more abundant in the presence of carp were the taxa most able to avoid carp predation and tolerate habitat changes caused by carp benthivory. To complement the small-spatial scale field experiment, large-scale patterns of carp distribution, biomass density and recruitment were explored among the rivers of New South Wales (Australia) in relation to their physical habitat. In contrast to expectations, and although most recruitment probably occurred at lower-altitudes, the populations with a size structure and biomass density most likely to cause ecological degradation occurred at intermediate altitudes. Furthermore, the distribution of smaller carp (less than or equal to 100 mm, and less than or equal to 300 mm) indicated that the regulation of river flows does not always favour carp populations, particularly during drought conditions. Nevertheless, it was concluded in a review of the carp literature, which incorporated the findings of this study, that invasion by alien carp is most successful in streams with formerly highly variable flows that are now subject to flow regulation. Moreover, carp are likely to enhance their advantage in these waters through habitat modification.
114

Quality characteristics of common carp (Cyprinus carpio) Surimi and Kamaboko and the role of Sarcaoplasmic Proteins

Jafarpour Khozaghi, Seyed Ali, ali.jafarpour@rmit.edu.au January 2008 (has links)
This study was carried out to determine the characteristics of common carp surimi. In Australia, common carp (Cyprinus carpio) is an environmental pest, strongly coloured (dark-muscle fish), large (2-3 kg), low cost (AUD 2.5/kg) and not highly valued as it is every where else. Surimi could add value to carp, but the colour would have to be modified as surimi manufacturers prefer white coloured flesh. So, firstly the efficiency of Hydrogen peroxide (H2O2; 1-3% v/v) solution at alkaline side of pH (7.0-11.5) on whitening of light fillets of common carp was examined. The whiteness (L*-3b*) of surimi produced from treated (3% H2O2, pH 8.2) common carp light fillets was significantly (p less than 0.05) greater than that of threadfin bream surimi and was not significantly different to that of Alaska pollock. Based on a temperature sweep test, a similar pattern in G of tested surimi was observed which started at ca. 47?C and was completed at ca. 73-74?C. However, thread fin bream kamaboko showed better texture profile characteristics (hardness and gel strength) than that of the other kamaboko tested. To improve the quality of common carp surimi and kamaboko, alternative methods were applied such as modified conventional method (MCM), alkaline-aided method (AAM) and pH modified method (PMM) and the resultant surimi and kamaboko were compared with those produced by the traditional method (TM). In MCM each washing cycle was followed by a centrifugation step for a more effective dewatering and removal of sarcoplasmic proteins (Sp-P). Kamaboko prepared from MCM was whiter and had significantly (p less than 0.05) improved textural characteristics (hardness and gel strength) than that from TM, AAM and PMM. Furthermore, SEM of surimi and kamaboko showed higher number of polygonal structure/mm2 in the gel matrix of MCM kamaboko, as a result of more cross-linking of the myofibrillar proteins, than that recorded for TM, AAM and PMM samples tested. Finally, this study examined the effect of adding common carp sarcoplasmic proteins (Sp-P) on the gel characteristics of threadfin bream surimi and kamaboko. Based on the temperature sweep test, the depths of the valley in the G thermograph of the gels decreased as the concentration of added Sp-P increased from 5% to 35%. Storage modulus (G) of the gels showed greater elasticity in the samples with added Sp-P compared with the control samples without added Sp-P. Furthermore, the breaking force and breaking distance and consequently gel strength of the resultant kamaboko were improved, significantly (p less than 0.05) with added Sp-P. Thus, added Sp-P did not interfere with the gelling of myofibrillar proteins during sol-gel transition phase and was associated with textural quality enhancement for the resultant kamaboko. However, the addition of freeze-dried Sp-P from the dark muscle of the carp decreased the whiteness of the resultant surimi. Furthermore, the gel strength could not be associated with either the number of polygonal structures/mm2 or the area of the polygonal structures.
115

Experimental manipulation of connectivity and common carp: the effects on native fish, water-column invertebrates, and amphibians in Delta Marsh, Manitoba

Parks, Candace R. 05 April 2007 (has links)
Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restrict or exclude carp access into ponds, channels were either screened or diked to four ponds. Two connected and two isolated ponds functioned as controls. Although common carp were the original subject of the study, it became apparent that hydrological connection to the surrounding marsh had a paramount importance on the abundance and diversity of the fish, amphibian and water-column invertebrate communities. Connectivity, or lack of connectivity, played an important role in the distribution of the fish community, and subsequently the composition and abundance of water-column invertebrates and amphibians. Ponds with direct connection had diverse, mixed-species fish assemblages, with fewer invertebrates and amphibians. Ponds with restricted connections had fish communities composed of tolerant small-sized species and increased abundance of invertebrates and amphibians. Ponds that lacked connection could freeze and lose all fish, and had higher numbers of invertebrates and amphibians. An absence of adult common carp may have been responsible for increased amphibian numbers in the screened ponds, however more study is needed. Confounding impacts of fluctuating water levels made it impossible to implicate common carp for most changes observed within ponds in Delta Marsh. / May 2006
116

Sazan (Cyprinus carpio) ve sudak (Stizostedion lucioperca) balıklarında gastrointestinal kanalın histokimyasal yapısı ve bazı peptidlerin lokalizasyonu /

Şenol, Nurgül. Eren, Ülker. Çınar, Kenan. January 2009 (has links) (PDF)
Tez (Doktora) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Biyoloji Anabilim Dalı, 2009. / Kaynakça var.
117

Berichte aus der Fischerei / Fishery reports

Rümmler, Frank, Wedekind, Helmut, Pfeifer, Matthias 09 November 2006 (has links) (PDF)
Die Studie enthält zwei Berichte. Rümmler, Heidrich und Pfeifer berichten über die kombinierte Satzkarpfen-Edelfischaufzucht in geschlossenen Kreislaufanlagen. Im zweiten Bericht referieren die Autoren Heidrich, Wedekind und Pfeifer über Optimierung biologischer und technologischer Parameter für die Aufzucht von Stören in geschlossenen Kreislaufanlagen.
118

Grass carp activin: molecular cloning and functional role in regulating growth hormone gene expression in grasscarp pituitary cells

Fung, Sai-kit., 馮世傑. January 2004 (has links)
published_or_final_version / abstract / toc / Zoology / Master / Master of Philosophy
119

Einfluss der Fütterung auf die Qualität von Kaviar

Füllner, Gert, Pfeifer, Matthias, Stähler, Georg, Pistor, René 06 May 2015 (has links) (PDF)
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.
120

Experimental manipulation of connectivity and common carp: the effects on native fish, water-column invertebrates, and amphibians in Delta Marsh, Manitoba

Parks, Candace R. 05 April 2006 (has links)
Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restrict or exclude carp access into ponds, channels were either screened or diked to four ponds. Two connected and two isolated ponds functioned as controls. Although common carp were the original subject of the study, it became apparent that hydrological connection to the surrounding marsh had a paramount importance on the abundance and diversity of the fish, amphibian and water-column invertebrate communities. Connectivity, or lack of connectivity, played an important role in the distribution of the fish community, and subsequently the composition and abundance of water-column invertebrates and amphibians. Ponds with direct connection had diverse, mixed-species fish assemblages, with fewer invertebrates and amphibians. Ponds with restricted connections had fish communities composed of tolerant small-sized species and increased abundance of invertebrates and amphibians. Ponds that lacked connection could freeze and lose all fish, and had higher numbers of invertebrates and amphibians. An absence of adult common carp may have been responsible for increased amphibian numbers in the screened ponds, however more study is needed. Confounding impacts of fluctuating water levels made it impossible to implicate common carp for most changes observed within ponds in Delta Marsh.

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