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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.
41

Testování účinnosti vybraných antiparazitik na metacerkárie motolice oční (Diplostomum spathaceum) u amura bílého (Ctenopharyngodon idella). / Testing of the efficiency of selected antiparasitics on the metacercaria of the eye flukes (Diplostomum spathaceum) in grass carp (Ctenopharyngodon idella).

MICHÁLKOVÁ, Jarmila January 2017 (has links)
In this thesis, the efficiency of orally applied praziquantel (PQ) in two concentrations (Pramik 1 and Pramik 2) and mebendazole (MB) were tested on metacercaria of eye flukes (Diplostomum spathaceum, Rudolphi, 1819) in the grass carp (Ctenopharyngodon idella, Valenciennes, 1844). Naturally infected fish (average fish weight was 1.6 g and standard deviation was 0.1) were divided into four groups, for each tested group (Pramik 1, Pramik 2 and MB) belonged two aquariums of 100 liters each with 25 fish and for a control group belonged three aquariums of 100 liters each with 25 fish. The fish in the individual groups were fed with medicated feed containing praziquantel (Pramik 1 - 2.5 g PQ. kg-1 of feed, Pramik 2 - 1.25 g PQ. kg-1 of feed) and medicated feed mixture KP1 enriched with mebendazole (2.5 g MB. kg-1 of feed). The control group was fed with KP1 without drug addition. During the test the parasitological examinations of the ophthalmic lens were performed. The prevalence and intensity of infection were recorded. In the group of fish fed with medicated mixture containing MB, no statistically significant differences of the intensity of the infection indicating the MB potential in the fight against this fish infection were reported during the test. In the case of tested groups of fish fed with medicated feed mixture containing PQ (Pramik 1, Pramik 2), a statistically significant difference in the intensity of the infection was proved compared with the control group already after the first examination (estimated dose of consumed PQ. kg-1 of weight of fish = 500 and 250 mg). Near complete elimination of the eye flukes occurred in the group fed with feed mixture Pramik 1 after the expected consumption of 900 mg PQ. kg-1 of weight of fish. Statistically significant differences in the intensity of the infection in PQ treated fish groups compared to control groups indicate the usability of medicated feed containing PQ in the fight against fish diplostomosis.
42

Ondersoeke na die kunsmatige teelt en produksiepotensiaal van die Europese en Sjinese karpsoorte, Cyprinus carpio, Hypophthalmichthys molitrix en Ctenopharyngodon idella, met verwysing na die benuttingsvermoe van probleemwaterplante deur die Sjinese graskarp

Brandt, Feltus de Waal 02 June 2014 (has links)
Ph.D. (Zoology) / Please refer to full text to view abstract
43

'n Ekologiese studie van die Floridameer, Roodepoort, met spesiale verwysing na die biologiese beheer van probleemwaterplante

Venter, Andries J.A. 13 February 2014 (has links)
M.Sc. (Zoology) / Ari investigation was made into the biological control of the submerged aquatic weeds Potamogeton pectinatus, Lagarosiphon major and L. muscoides in the Florida Lake, Transvaal using the Chinese grass carp Ctenopharyngodon idella (Val.) as biological control agent. The physical, chemical (including selected heavy metals), faunal and bacteriological conditions were also investigated over a period of one year. The total standing crop of P.pectinatusand Lagarosiphon spp, were reduced from an initial 0,193 kg m" 2 (wet mass) in March 1990 to 0,0338kg m-2 (wet mass) in March 1991. Reductions in the densities of the macrophytes coincided with a corresponding increase in chIorophyll-a values in the water columm of the lake. Abnormally high concentrations of the heavy metals copper, manganese, iron, nickel chromium, zinc and lead were found to occur in the lake sediments, aquatic macrophytes, ftlamentous algae, macroinvertebrate fauna as well as in organs and tissues of the perch Perea fluviatilis. These metals could be related to gold mining activities which occurred in the vicinity of the lake some years ago. Faecal bacterial counts of the water in the lake point towards the possible contamination of the lake water with domestic sewage. Ari analysis of the faeces of the numerically dominant birds which occur at the lake i.e. the coot Fulica aistata and the egyptian goose Alopochen aegyptiacus suggest that the main cause of faecal contamination of the lake's water possibly originates from these and other water birds frequenting the lake. By using the results on the physical-chemical conditions in the lake, conditions which presently prevail can be summarized as being largely that of a mesotrophic impoundment with strong tendencies towards eutrophic conditions. Secondary effects of the grass carp on the lake ecosystem was the progressive decline of weed eating birds and a slight increase in the numbers of piscivorous birds, both of which could be linked to the drastic reduction in the standing crop of the submerged weeds in the Lake. The present survey confirms the value of the Chinese grass carp as biological control agent in the management of excessive growths of submerged aquatic weeds in lakes and reservoirs in South Africa...
44

Corbicula fluminea Invasion as a Secondary Effect of Hydrilla verticillata Management via Triploid Grass Carp (Ctenopharyngodon idella)

Holbrook, David Lee 12 1900 (has links)
A study of Asian clam (Corbicula fluminea Müller) colonization in relation to changes in aquatic vegetation community as a result of management of Hydrilla verticillata (L. f.) Royle with grass carp was conducted at the Lewisville Aquatic Ecosystem Research Facility (LAERF), Lewisville, TX, from April 2015 through October 2016. Percent vegetation cover, C. fluminea abundance and water quality metrics (pH, turbidity, conductivity, DO, calcium, chlorophyll a) from 16 experimental subjects were analyzed. Treatments included four replicated grass carp stocking densities; 1-control with no fish stocked (n = 4), 2-low density of 40-43 fish per vegetated ha (n = 4), 3-medium density of 72-81 fish per vegetated ha (n = 4) and 4-high density of 110-129 fish per vegetated ha (n = 4). Data analysis showed statistical significance in the relation of C. fluminea abundance to percent vegetation cover (multiple linear regression, r2 = 0.820), grass carp stocking densities (two-way analysis of variance, p = <0.001) and chlorophyll a (multiple linear regression, r2 = 0.339). Findings of this research indicate the possibility that management of hydrilla had enabled establishment of secondary invasive species.
45

Probiótico, prebiótico e simbiótico na nutrição de juvenis de carpa capim

Geraldo, Andressa Mariza Ribeiro 21 July 2016 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T17:38:31Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) ANDRESSA MARIZA RIBEIRO GERALDO.pdf: 730207 bytes, checksum: 5df837babcc118e5f1db740d596c32b6 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T17:42:09Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) ANDRESSA MARIZA RIBEIRO GERALDO.pdf: 730207 bytes, checksum: 5df837babcc118e5f1db740d596c32b6 (MD5) / Made available in DSpace on 2017-06-05T17:42:09Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) ANDRESSA MARIZA RIBEIRO GERALDO.pdf: 730207 bytes, checksum: 5df837babcc118e5f1db740d596c32b6 (MD5) Previous issue date: 2016-07-21 / O objetivo deste estudo foi avaliar o desempenho de carpas capim (Ctenopharyngodon idella) alimentadas com dietas suplementadas com diferentes aditivos no consumo de forragem teosinto (Euchlaena mexicana). O delineamento foi inteiramente casualizado com 4 tratamentos em triplicata, sendo, TCont: dieta controle; TPre: dieta com prebiótico (casca de soja: 5%/Kg de ração); TPro: dieta com probiótico (B. cereus e B. subtilis: 0,5%/Kg de ração) e TSim: dieta com simbiótico (níveis de probiótico e prebiótico juntos). As rações formuladas tinham 30% PB e 3000 kcal/ED/Kg. O período experimental foi de 70 dias nos quais os peixes foram alimentados com 3% PV de ração e forragem ofertada a vontade. Foram avaliados os parâmetros de desempenho zootécnico, conversão alimentar aparente, índices corpóreos, análise centesimal corporal e parâmetros hematológicos. Para análise estatística foi realizada ANOVA com P<0,05 e teste de comparação de médias. Os resultados indicaram que a inclusão de probiótico, prebiótico e simbiótico na concentração usada apresentaram melhor consumo de forragem em relação ao controle, mas não em relação o desempenho zootécnico dos animais. Também, a inclusão dos aditivos proporcionou menor gordura corporal nos animais. Palavras chave: Aquicultura. Bacillus cereus. Bacillus subtilis. Casca de soja. Ctenopharyngodon idella. Nutrição de peixes. / The aim of this study was to evaluate the performance of grass carp (Ctenopharyngodon idella) fed diets supplemented with different additives in the consumption of forage teosinte (Euchlaena mexicana). The experimental design was completely randomized with 4 treatments in triplicate being TCont: control diet; Tpre: prebiotic (soybean hulls: 5%/kg of diet); TPro: Probiotic (B. cereus and B. subtilis: 0.5%/kg of diet) and Tsyn: synbiotic (probiotic and prebiotic levels together). The diets formulated had 30% CP and 3000 kcal / DE / kg. The experimental period was 70 days in which fish were fed 3% BW feed and forage offered ad libitum. It were evaluated the growth performance parameters, aparent feed conversion, corporeal indices, chemical analysis of the boby and hematological parameters. Statistical analysis was performed with ANOVA P <0.05 and mean comparison test. The results may indicate that the addition of probiotic, prebiotic and synbiotic in the concentration used showed better forage intake compared to control, but not over the growth performance of animals. Also, the inclusion of additives provided lower body fat in animals.
46

Assessment of Changes in Aquatic Macrophyte Occurrence Following Introduction of Triploid Grass Carp in a North Texas Reservoir

Bickel, Ken (Kenneth E.) 08 1900 (has links)
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.
47

Citlivost adultních ryb různých druhů k anestetiku hřebíčkový olej / Sensitivity to anesthetic clove oil different species of adult fish

ŠKEŘÍK, Jindřich January 2007 (has links)
Nomenclature: Sensitivity to anesthetic clove oil different species of adult fish Sensitivity of breeding fishes of various species (Siberian sturgeon, Brook trout, Black carp- young breeding fishes) for anesthetic clove oil was probed by the tests performed at temperature in the period of stripping (apart from Brook trout and Black carp). The tests were carried out with 17 fish species- with cyprinids (Ide- golden form, Common dace, European Chub, Sneep, Barbel, Grass carp, Black carp, bighead carp), salmonids (Brown trout, Rainbow trout, Brook trout), thymallinae (Grayling), pikes (Northern pike), perches (Pike-perch), sturgeons (Siberian sturgeon, Beluga) and airbreathing catfishes (North African catfish). Using concentration of 0,03ml.l-1 (Brown trout, Rainbow trout, Brook trout, Grayling, Pike, Pike perch, Ide, Dace, Chub, Barbel and Sneep), 0,04ml.l-1 (Grass carp, Black carp, Bighead carp), 0,05ml.l-1 (North African catfish) and 0,07ml.l-1 (Siberian sturgeon, Beluga) the IIb. Phase has been achieved, which is sufficient for manipulation with fishes during stripping. The anesthesia subsided after time period of 10-17 minutes (12 species) at the majority of fishes and at others after interval of 20-26 minutes (5 species). The results confirmed concentrations recommended for salmodis and Grayling (0,025-0,03ml.l-1), sturgeons (0,07ml.l-1), and North African catfish (0,05ml.l-1). At the majority of cyprinids (apart from Grass carp, Black carp and Bighead carp), the concentration used was lower than recommended (0,04-0,05ml.l-1)

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