The object of this study is to design demembranation method on four freshwater species and its application on study of the influence of HgCl2 on the axoneme and motity sperm motility parameters. Demembranation was designed and examined for all investigated species common carp (Cyprinus carpio), sterlet (Acipenser ruthenus), perch (Perca fluviatilis) and african catfish (Clarias gariepinus). One-step and two-step method was designed and tested for common carp. One-step method was designed for sterlet and perch. Two-step method of demembranation was designed for african catfish. Demembranation was designed and examined for all species under examination. Sperm motility was evidently increased above normal physiological value. Other sperm motility parameters (velocity, percent of motile cells) slightly decreased. HgCl2 in concentration 0,01 mM to the demembranation medium didn't show effect on flagellar microtubule aparat and then to the motility parameters, except sterlet; demembranated sterlet sperm was inhibited at all used concentration of HgCl2. Concentration 0,1 mM had inhibition effect on carp and africant catfish spermatozoa. Concentration 1 mM HgCl2 inhibited sperm of all tested species.

The aim of this diploma thesis was to test the production effectiveness of cereals and compound feed and at the same time, find out what influence they have on the water quality when applied in the semi-intensity carp farming. The feeding test was taking place in the period of 112 days in 10 experimental storage ponds. The feed which was tested, was cereals, extruded feed from the Aller Aqua company with 24% share of protein, pelleted feed glycid type feed with the 12,5% share of protein (KP) and pellet feed glycid type compound feed with 12,5% share of protein and reduced share of phosphorus (KPminus). A tested carp population of the same density was left without any additional feeding, to be fed only on the natural nutrition. Every one of these separated carp populations were fed three times a week in the morning and on the same spot of the fish tank. The testing was taking place twice.The measuring of the parametres of the water (temperature, oxygen, pH) took place once a fortnight, taking samples of the water once a month. At the end of the experiment, the level of phosphorus and the observed production parametres were evaluated.The highest production effectiveness was reached in the carps that were fed with cereals (FCR - Food Convertion Ration 2,41 - 0,46, SGR - Specific Growth Rate 0,54 - 0,07 %.d-1). The lowest production effectiveness was achieved with the pelleted feed KPminus (FCR - 3,72 - 0,30, SGR - 0,39 - 0,02 %.d-1). The highest retention of phosphorus (88%) in the fish biomass was reached with cereals. The lowest retention of phosphorus (60%) was reached in the carps fed with the pelleted feed KP. Feeding carps with tested feeds did not have any significant influence on the water quality. From both the economic and the environmental point of view, the best feed for carp pond farming is cereals.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pesticides can affect toxicological parameters and cause oxidative stress in fish. In Brazil there are few studies linking pesticide toxicity with fish. For this reason, two experiments were conducted to evaluate possible effects of herbicides on some toxicological parameters in carp (Cyprinus carpio). The fish were exposed to two commercial herbicides, one composed of a mixture formulated imazetapir and imazapic and the second composed of clomazone. The periods of exposure were seven days in the laboratory and seven, 30 or 90 days on rice field condition. After the experimental period, metabolic and toxicological parameters in the liver, brain and muscle tissues were evaluated. The enzymatic parameters analyzed in different tissues of this species were acetylcholinesterase activity (AChE), catalase (CAT) and glutathione S-transferase (GST). Also, oxidative stress parameters, such as carbonyl protein and TBARS levels in hepatic tissue, were analyzed. The metabolic parameters analyzed in liver and muscle of carp were glucose, glycogen, lactate, protein, amino acids and ammonia. Moreover, metabolic assessments were made (glucose, lactate and protein) in carp plasma. The results showed that AChE activity was increased in carp brain after seven days of exposure to a commercial formulation containing imazethapyr and imazapic herbicides both under field and laboratory conditions. In the same period of exposure, muscle tissue showed reduced activity of AChE after exposure to all herbicides (imazetapir and imazapic and clomazone) under laboratory conditions. At 30 days, in the field, AChE activity was reduced in brain and enhanced in muscle of carps exposed to imazethapyr and imazapic. Fish exposed to clomazone herbicide did not show any change in the activity of this enzyme in this period. On the other hand, at 90 days of exposure, only the fish exposed to the herbicide clomazone, showed a reduction in muscle AChE activity. The antioxidant enzyme catalase showed increased activity in liver tissue after seven days of exposure under both experimental conditions. At 30 days of exposure, catalase activity showed no further changes and after 90 days of exposure activity was reduced in liver of carp exposed to clomazone herbicide. The enzyme glutathione S-transferase was altered only after 30 and 90 days of exposure in the field. GST activity was reduced in liver tissue after exposure to both herbicides tested. TBARS levels were increased in almost all periods, terms of exposure and tissues considered, with the exception of brain tissue, which presented a decrease in TBARS levels at 30 days of exposure. Protein carbonyl was reduced in liver of carp exposed to clomazone herbicide after seven days under laboratory conditions. Moreover, at 30 and 90 days of exposure, the protein carbonyl levels were increased in the liver of fish exposed to both herbicides. After exposure to both herbicides, the carp showed metabolic disorders. In general, protein and amino acid levels were reduced and the amount of glycogen was enhanced in liver and muscle of carp exposed to both herbicides at all times tested. However, ammonia, lactate and glucose levels were increased and reduced according to the tissue considered, time of exposure and herbicide tested. These results indicate that the parameters measured may be good indicators of contamination of these commercial herbicides in Cyprinus carpio. / Os pesticidas podem afetar parâmetros toxicológicos e ainda causar estresse oxidativo em peixes. No Brasil existem poucos estudos relacionando toxicidade de pesticidas com peixes. Por esta razão foram conduzidos dois experimentos com objetivo de avaliar possíveis efeitos dos herbicidas sobre alguns parâmetros toxicológicos em carpas (Cyprinus carpio). Os peixes foram expostos a dois herbicidas comerciais, um composto pela mistura formulada de imazetapir e imazapic e o segundo composto por clomazone. Os períodos de exposição foram de sete dias em laboratório e por sete, 30 ou 90 dias em condição de lavoura de arroz. Após os períodos experimentais, nos tecidos hepático, cerebral e muscular foram avaliados parâmetros metabólicos e toxicológicos. Os parâmetros enzimáticos analisados foram a atividade da acetilcolinesterase (AChE), catalase (CAT) e glutationa S-transferase (GST) em diferentes tecidos desta espécie. Além disso, analisaram-se parâmetros de estresse oxidativo, como a carbonilação de proteínas e níveis de TBARS no tecido hepático. Os parâmetros metabólicos analisados foram glicose, glicogênio, lactato, proteína, amônia e aminoácidos em fígado e músculo de carpas. Ademais, foram feitas avaliações metabólicas (glicose, lactato e proteína) em plasma de carpas. Os resultados mostraram que a atividade da AChE foi aumentada em cérebro de carpas, após sete dias de exposição a formulação comercial contendo os herbicidas imazetapir e imazapic, em condições de campo e laboratório. Neste mesmo período de exposição, o tecido muscular mostrou redução da atividade da AChE após exposição as duas formulações comerciais em laboratório. Aos 30 dias em campo, a atividade da enzima AChE foi reduzida em cérebro e aumentada em músculo de carpas expostas a formulação contendo a mistura dos herbicidas imazetapir e imazapic. Os peixes expostos ao herbicida clomazone não mostraram alteração na atividade desta enzima, neste período. Já aos 90 dias de exposição, somente os peixes expostos ao herbicida clomazone, mostraram uma redução na atividade da AChE muscular. A enzima antioxidante catalase mostrou sua atividade aumentada no tecido hepático após sete dias de exposição em ambas as condições experimentais e às duas formulações comerciais testadas. Aos 30 dias de exposição, a enzima não foi alterada e após 90 dias de exposição a sua atividade foi reduzida em fígado de carpas expostas ao herbicida clomazone. A enzima glutationa S-transferase só foi alterada após 30 e 90 dias de exposição em campo. Sua atividade foi reduzida no tecido hepático após exposição às formulações comerciais dos herbicidas testados. Os níveis de TBARS foram aumentados em praticamente todos os períodos, condições de exposição e tecidos considerados, com exceção do tecido cerebral que aos 30 dias de exposição, mostrou os níveis de TBARS diminuídos. Os níveis de proteína carbonil foram diminuídos em fígado de carpas expostas por sete dias ao herbicida clomazone em laboratório. Por outro lado, aos 30 e 90 dias de exposição os níveis de proteína carbonil foram aumentados no fígado de peixes expostos as duas formulações comerciais. Após exposição aos dois herbicidas comerciais, as carpas demonstraram desordens metabólicas. De uma maneira geral, os níveis de proteína e aminoácidos foram diminuídos e o conteúdo de glicogênio aumentado em fígado e músculo de carpas expostas aos dois herbicidas comerciais e tempos testados. Porém, os níveis de amônia, lactato e glicose mostraram alterações variáveis de acordo com o tecido considerado, com o tempo de exposição e com o herbicida testado. Estes resultados indicam que os parâmetros medidos podem ser bons indicadores da contaminação destes herbicidas comerciais em Cyprinus carpio.

The study summarizes methods of artificiale and semiartificiale reproduction of pikeperch. The aim of the present study is to study ovulation rate by injection of different hormones: carp pituitary, analogs of GnRH Supergestran, Ovopel (containing dopamine inhibitor), Dagin (containing too dopamine inhibitor) in zander (Sander lucioperca) and determination of stripped eggs to broodstock weight, relative and absolute fertility and period of latency. On the basis of results, zander can be considered to be usefull species for semiartificiale and artificiale propagation.

Small cyprinid fish, the topmouth gudgeon (Pseudorasbora parva Schlegel, 1842) is considered as an undesirable fish species because it represents an important food competitor for commercial non-predatory fishes. This study was performed under pond conditions (four ponds in South Moravia and two ponds in South Bohemia) during the growing seasons in 2006 {--} 2007. The purpose of my work was to determinate the level of food competition between topmouth gudgeon and common carp (Cyprinus carpio) as a dominating pond fish species. Food selectivity was evaluated using Ivlev´s electivity index (Jacobs, 1974). The level of food competition between common carp and topmouth gudgeon was used to evaluate the index of food similarity according to Shorygin (1952). The diet of topmouth gudgeon consisted mainly of chironomid larvae and zooplankton, mostly cladocerans (Daphnia, Bosmina), detritus and periphyton (Oscillatoria, Scenedesmus, Sphaerotilus). Macrophytes, copepods and Brachionus were also ingested by P.parva but in comparatively low proportions. In contrast, carp diet consisted mainly of bottom items including chironomid larvae, macrophytes and organic debris, mainly detritus and periphyton. The food items of lesser importance were dragon fly (Anisoptera) larvae, cladocerans (Bosmina, Daphnia) and ostracods. Topmouth gudgeon competed with common carp for chironomid larvae, periphyton and detritus, for zooplankton (mainly cladocerans Daphnia, Bosmina). The highest valuation the food competition was registered in fish from the Vracovický pond (South Moravia) and the Podsedek pond (South Bohemia), when it amounted from 24.02 to 34.78 % food similarity.

The objectives of this project were to measure changes in frequency of occurrence of submerged macrophytes over the first two growing seasons following stocking with triploid grass carp at two fish per acre and to measure differences in macrophyte biomass between areas excluded from herbivory and adjacent control sites after 16 months following establishment of exclosures. The project also seeks to measure concentrations of fluridone following the herbicide treatment, and to compare two methods of aquatic vegetation sampling.

No description available.

Twenty-nine (Group One, June 8,1995) grass carp (Ctenopharyngodon idella) and five (Group Two, April 18, 1996) grass carp were radio-tagged to monitor movement patterns and habitat preferences on North Lake, a 335 hectare multi-use reservoir located in Irving, Texas. Overall fish mean Average Daily Movement (ADM) rates were 49.2 meters/day (during Half One, 6/8/95-11/30/95) and 5.3 meters/day (during Half Two, 12/14/95-6/6/96). Aquatic macrophtye distribution data were obtained. Radio-tagged grass carp were located in Hydrilla verticillata infested areas increasingly throughout the study, however, percent frequency of Hydrilla along 15 transects did not decrease. Radio-transmitters were equipped with temperature-sensors (10-35 Celsius range). Results indicated that radio-tagged grass carp showed no avoidance of areas of North Lake with elevated water temperatures. Radio-tagged grass carp dispersed quickly from stocking point, then moved into littoral areas infested with Hydrilla. After an initial movement period, most fish remained in a localized area.

The need for more sustainable protein sources is growing globally due to the significant climate impact from the food system and the estimated population growth. Although vegetarian protein sources have been proven to be sustainable alternatives, there may exist additional resources that currently are not utilized but potentially could contribute as sustainable protein sources. Life Cycle Assessment (LCA) is an internationally standardized tool used to assess the potential environmental impacts of a product or service throughout its entire life cycle. The results from a recently conducted LCA for Swedish carp species showed that the average potential climate impact was 0.77 kg CO2-eq per kg of edible product, which is significantly lower than more commonly consumed protein sources. The bream is a carp fish that previously was consumed in Sweden, but now is caught only as a by-catch that is released back.  This study aims to assess the potential environmental impacts of minced bream produced in Stockholm and utilizing bream caught as by-catch to wild capture fishery in Mälaren. The study also investigates how the potential environmental impacts may change in alternative systems and how the potential climate impact compares to the potential climate impact of other protein sources consumed in Sweden. The results of the study confirm many of the conclusions made in reviewed literature, such as the wild capture fishery and transports being identified hotspots. The results also show a low potential environmental impact of the minced bream in the current system but significant increases in the potential environmental impacts if the minced bream was produced in the alternative systems. In comparison to other protein sources, the minced bream shows great potential, both now and in the future when the carbon budget may be limited to 0.5 kg CO2-eq per meal if we are to limit global warming to 1.5°Cabove pre-industrial levels.  Further studies are encouraged to collect more data and provide a better understanding of the environmental impacts of fish products. However, the results could function as an important benchmark that also highlights the potential of currently underutilized species of fish. / Behovet av mer hållbara proteinkällor ökar globalt till följd av matproduktionens stora klimatavtryck samt uppskattningar om en snabbt växande befolkning. Även om vegetariska proteinkällor har visats vara hållbara alternativ, finns en möjlighet att även andra resurser som i dagsläget inte utnyttjas har potential att bidra som hållbara proteinkällor. Livscykelanalys (LCA) är ett internationellt standardiserat verktyg som används för att utvärdera den potentiella miljöpåverkan från en produkt eller tjänst under hela livscykeln. En nyligen genomförd LCA visar att svenska karpfiskar har ett genomsnittligt potentiellt klimatavtryck på 0.77 kg CO2- ekvivalenter per kg ätlig produkt, vilket är avsevärt mycket lägre den potentiella klimatpåverkan hos många av de proteinkällor som idag konsumeras i större utsträckning. Braxen är en karpfisk som tidigare konsumerats i Sverige men som numera fångas enbart som en bifångst som släpps tillbaka.  Denna studie syftar till att utvärdera den potentiella miljöpåverkan av braxenfärs som produceras i Stockholm på braxen fångad som bifångst till gösfiske i Mälaren. Studien undersöker också hur den potentiella miljöpåverkan kan förändras i alternativa system och hur den potentiella klimatpåverkan kan jämföras med den potentiella klimatpåverkan från andra proteinkällor som konsumeras i Sverige. Resultaten från studien bekräftar många av slutsatserna i litteraturen som granskats, som att fisket och transporter identifierats som hotspots. Resultatet visar också en låg potentiell miljöpåverkan från braxenfärsen i det nuvarande systemet men en betydande ökning av den potentiella miljöpåverkan om braxenfärsen produceras i de alternativa systemen. Jämfört med andra proteinkällor visar braxenfärsen stor potential både nu och i framtiden när koldioxidbudgeten kan begränsas till 0.5 kg CO2-ekvivalenter per huvudmåltid om den globala uppvärmningen ska begränsas till 1.5 °Cöver förindustriella nivåer.  Ytterligare studier uppmuntras för att samla in mer data och ge en bättre förståelse för fiskprodukters miljöpåverkan. Resultatet kan dock fungera som ett viktigt riktmärke som också belyser potentialen hos för närvarande underutnyttjade fiskarter.

Invasive exotic species threaten native biodiversity, alter ecosystem structure and function, and annually cost over $100 billion in the US alone. Determining the ecological traits and interactions that affect invasion success are thus critical for predicting, preventing, and mitigating the negative effects of biological invasions. Native herbivores are widely assumed to facilitate exotic plant invasions by preferentially consuming native plants and avoiding exotic plants. Here, I use freshwater plant communities scattered broadly across the Southeastern U.S. to show that herbivory is an important force driving the ecology and evolution of freshwater systems. However, native consumers often preferentially consume rather than avoid exotic over native plants. Analyses of 3 terrestrial datasets showed similar patterns, with native herbivores generally preferring exotic plants. Thus, exotic plants appear defensively nave against these evolutionarily novel consumers, and exotic plants may escape their coevolved, specialist herbivores only to be preferentially consumed by the native generalist herbivores in their new ranges. In further support of this hypothesis, a meta-analysis of 71 manipulative field studies including over 100 exotic plant species and 400 native plant species from terrestrial, aquatic, and marine systems revealed that native herbivores strongly suppressed exotic plants, while exotic herbivores enhanced the abundance and species richness of exotic plants by suppressing native plants. Both outcomes are consistent with the hypothesis that prey are susceptible to evolutionarily novel consumers. Thus, native herbivores provide biotic resistance to plant invasions, but the widespread replacement of native with exotic herbivores eliminates this ecosystem service, facilitates plant invasions, and triggers an invasional meltdown. Consequently, rather than thriving because they escape their co-evolved specialist herbivores, exotic plants may thrive because their co-evolved generalist herbivores have stronger negative effects on evolutionarily nave, native plants.