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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.
211

Fish health, condition and biomarkers : a mechanistic and environmental perspective on copper pollution / Daléne van Heerden

Van Heerden, Daléne January 2005 (has links)
Thesis (Ph.D. (Zoology))--North-West University, Potchefstroom Campus, 2005
212

The effect of dietary L-carntine [i.e. carnitine] supplementation on production performance parameters of Mozambique tilapia, Oreochromis mossambicus, at sub-optimal water temperature

Tekle, Esayas Welday 12 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: 60-day growth experiment was conducted to investigate the effect of dietary Lcarnitine supplementation on the production performance parameters of Mozambique tilapia, Oreochromis mosambicus. A number of approximately 140 tilapia fry with average weight of l.4g ± 0.71g were stocked in each of 40 fine-meshed hapas (I mx 1mx 1.5m) submerged within a complete recirculation pond system. During the first 30 days of the experiment water temperatures ranged from 19 to 23°C where after it decreased to 16-20°C for the consecutive 30-day period. Dietary treatments consisted of 8 replicates of 5 levels of L-carnitine supplementation labelled as Co, C250,C500, C750 and C 1000represented Omg, 250mg, 500mg, 750mg and 1000mg L-carnitine supplementation per kg feed respectively. Results were analyzed for significant differences using one-way analysis of variance (ANOVA) and Tukey's pairwise comparison test for growth rate, feed intake (FI) and feed conversion efficiency. After completion of the trial 8 fish from each hapa were sacrificed and analyzed for cephalosomatic index (CSI), dress out percentage (viscera, gills and head excluded), viscerosomatic index (VSI) and hepatosomatic index (HSl). Poor production performance results were generally observed as water temperatures were sub-optimal, especially during the second 30-days period. Results from the trial indicate no significant differences (P>0.05) between treatments for weight gain, FCR, FI and VS!. A negative trend was observed for FCR with increasing level of L-carnitine supplementation for both the first 30-day period (1.50±0.07, 1.53±0.08, 1.58±0.09 and 1.61±0.17 for C250,C50Q,C750and C 1000)as well as for the consecutive lower temperature 30-day period (2.22±0.10, 2.25±0.ll, 2.27±0.28 and 2.29±0.2l for C250, C500, C750 and C 10(0)'Although statistically not significant, fish fed the C250showed better performance in dress out percentage weight either than the control or the higher levels. The increasing trend for head weight with increasing level of L-carnitine supplementation were significant (P<0.05) from Co and C250with and above C500.The decreasing trend for liver weight with increasing level of L-carnitine supplementation became significant (P<0.05) with and above C750.The results of the current study showed a trend in the improvement of L-carnitine on the production performance parameters. However, the natural content of L-carnitine in the basal diet impaired with the inclusion levels, thus further research at lower inclusion levels is recommended. / AFRIKAANSE OPSOMMING: 'n Proef oor 'n tydperk van 60-dae is onderneem om die effek van L-karniten aanvulling op produksie prestasie parameters van Mosambiek tilapia (0. mosambicusi te ondersoek. 140 tilapia vingerlinge met 'n gemiddelde massa van lAg ± 0.7lg is ewekansig uitgeplaas in 40 eksperimentele hapa-hokkies (lmxlmx1.5m) in "n hersirkulasie sementdam-stelsel. Gedurende die eerste 30 dae van die proef het water temperatuur gewissel tussen 19 to 23°C waarna dit gedaal het na tussen l6-20°C vir die opeenvolgende 30-dag periode. Proef-rantsoen behandelings het bestaan uit 8 herhalings van 5 vlakke van L-karnitien aanvulling, naamlik Co,C250, C500, C750 en CIOOOvir Omg, 250mg, 500mg, 750mg en 1000mg L-karnitien aanvulling per kg voer afsonderlik. Resultate was ontleed vir betekenisvolle verskille deur gebruik te maak van analise van variansie (ANOVA) ontleding en die Tukey se vergelykende toets vir groeitempo, voerinname en voeromsettingsverhouding. Aan die einde van die proefperiode is 8 visse van elke hapa ontleed vir liggaamskomponent-samestelling (kop-, ingewande- en hepatosomatiese indekse. Ondergemiddelde produksie resultate is waargeneem wat toegeskryf kan word aan onder-optimale water temperature, veral gedurende die tweede 30-dag periode van die proef. Proef resultate het geen betekenisvolle verskille (P>0.05) in massatoename, voeromsettingsverhouding (VOV) of visserosomatiese indeks tussen behandelings getoon nie. 'n Negatiewe neiging is waargeneem vir VOV met toenemende vlakke van L-kamitien insluiting vir beide die eerste 30 dag periode (1.50±0.07, 1.53±0.08, 1.58±0.09 and 1.61±0.17 for C250, C500, C750 and CIOOO) sowel as vir die opvolgende 30-day periode nie (2.22±0.10, 2.25±0.11, 2.27±0.28 and 2.29±0.21 for C250, C50o, C750 and CIOOO). 'n Toenemende neiging vir kop-massa met toenemende L-kamitien insluiting was betekenisvol (P<0.05) vanaf Co en C250 met en hoër as C500. 'n Dalende neiging vir lewermassa met toenemde L-kinsluiting was betekenisvol (P<0.05) met en hoër as C750. Resultate van die proef dui oor die algemeen op 'n neiging tot verbeterde produksie prestasie parameters van tilapia vingerlinge met toenemde insluiting van Lkamitien. Verdere navorsing word aanbeveel om die invloed van natuurlike Lkamitien in die proteïen-bronne van die basaalrantsoen te op die gebrek aan betekenisvolheid van hierdie neiging te verklaar.
213

Age-dependent effect of environmental light on spectral sensitivity and body colouration of Nile tilapia Oreochromis niloticus

Hornsby, Mark 06 December 2012 (has links)
Signal reception and production form the basis of animal communication, and are largely constrained by environmental biophysical factors such as environmental light. However, the role of environmental light in producing variation in either signal reception or production has not been fully investigated. Using two distinct environmental light treatments, as well as a third treatment for a sampling of adults, I recorded corneal electroretinograms, lens transmission, and spectral reflectance of the body pattern of juvenile and adult Nile tilapia to chart the effect of environmental light on visual sensitivity and body colouration throughout ontogeny. Environmental light had an age-dependent effect on spectral sensitivity and an age-independent effect on spectral reflectance. Spectral sensitivity in juveniles reared under a broad-spectrum light treatment and a red-shifted light treatment differed mostly at short wavelengths, where the irradiance of the two environmental light treatments differed the most. In contrast, adults reared under the two environmental light treatments did not differ in spectral sensitivity. Lens transmission did not differ significantly between environmental light treatments, indicating that differences in spectral sensitivity of juveniles originated in the retina. Both juveniles and adults reared under the two environmental light treatments differed in spectral reflectance, and adults transferred to the third environmental light treatment differed in spectral reflectance from their counterparts reared under the two original treatments. These results demonstrate that environmental light plays a large role in shaping signal reception in juveniles and signal production throughout ontogeny, suggesting that environmental light has the capacity to drive ecological speciation. / Thesis (Master, Biology) -- Queen's University, 2012-12-03 11:32:59.441
214

The evaluation of novel bio-ethanol derived co-products as potential feed ingredients for carp Cyprinus carpio and tilapia Oreochromis niloticus

Omar, Samd Sofy January 2012 (has links)
The nutritional value of novel yeast products were evaluated for warmwater fish species. A yeast co-product (yeast protein concentrate unrefined (YPCU)) obtained from a bio-ethanol process using wheat was tested using iso-nitrogenous (38% crude protein) and iso-lipidic (8%) diets for juvenile mirror carp (Cyprinus carpio). The fishmeal (FM) protein component of a basal diet was replaced by (YPCU) at 7.5, 15, 20, and 50% of total dietary protein. After an 8 week feeding trial, all fish fed YPCU yielded better growth performance than the control fed fish, with diets containing 15% and 20% YPCU being optimal. Whole body composition was unaffected by dietary treatment, however, ash levels were elevated in fish fed &gt;15% YPCU. Hepatic alanine amino transferase (ALAT) and aspartate amino transferase (ASAT) were measured as bio-indicators of liver function in carp. Only ASAT activity was significantly lower for carp fed 20% and 50% YPCU. Additionally, histological assessment of liver and intestinal tissues gave no indication of impairment, but high YPCU inclusion (&gt;15%) elevated the number of goblet cells present in the posterior intestine. Molecular microbiological analysis using DGGE revealed no definitive changes in intestinal microbial communities. In a second study, bio-ethanol yeast (refined YPCR and unrefined YPCU) and dried distillers grain with solubles (DDGS) a co-product of the bio-fuel process and distillery yeast from potable alcohol (whisky) production (YPCPA) were evaluated as before for carp. FM was replaced with 30% of YPCU, YPCR and YPCPA and 15, or 30 % DDGS with a combination of 10% YPCR. Weight gain, and Apparent Net Protein Utilization (ANPU%) were higher in fish fed YPCU 30%, equivalent for fish fed FM, YPCR 30%,DDGS 15% and DDGS 30%, and lower in fish fed YPCPA 30% diets. Feed conversion ratio was significantly increased in carp fed YPCU 30% and decreased for carp fed DDGS 30% and YPC PA 30% compared with the control group. A significant improvement of net mineral retention was seen for carp feed the yeast supplementation diets compared to the fishmeal control group. The YPCU 30% diet produced the highest mineral retention in fish fed yeasts and the YPCPA 30% gave lowest retention. The microvilli density of the intestinal tract decreased for carp fed YPCR 30%, but microvilli length significantly increased in fish fed YPCU 30% compared with other groups, thus indicating changes in gut integrity. In the third study, four diets were formulated to replace 0, 10, 20 and 30% of the fishmeal with refined yeast protein concentrate (YPCR) for Nile tilapia (O. niloticus) of mean weight 12.39g. Growth performance and feed efficiency were not affected with up to 20% replacement with YPCR. There were no obvious changes in the liver structure, but high yeast inclusion showed higher numbers of intestinal goblet cells with increasing YPCR dietary inclusion suggesting enhanced intestinal integrity. Microvilli density and length was significantly (P = 0.025) improved with up to 10% and 30% YPCR inclusion in comparison to other dietary treatments. It was generally concluded that YPC co-products were effectively viable for both juvenile carp and tilapia offering an option for partial fish meal replacement.
215

Die effek van swaarmetale by variërende pH op die bloedfisiologie en metaboliese ensieme van Tilapia sparrmanii (Cichlidae)

19 November 2014 (has links)
M.Sc. / Please refer to full text to view abstract
216

Atividade antimicrobiana do tianfenicol sobre bactérias patogênicas de peixes /

Assane, Inácio Mateus January 2018 (has links)
Orientador: Fabiana Pilarski / Banca: Jonas Augusto Rizzato Paschoal / Banca: Luiz Augusto do Amaral / Resumo: Os surtos de bacterioses na piscicultura são imprevisíveis, por essa razão é necessário dispor de opções terapêuticas eficazes para reduzir a morbidade e mortalidade. Para que a terapia seja eficaz, a escolha do antimicrobiano deve se basear nas informações farmacocinéticas do fármaco no hospedeiro, nas condições de produção e na sensibilidade do patógeno. No Brasil, atualmente só dois antimicrobianos são legalizados para uso na aquicultura, a oxitetraciclina (OTC) e o florfenicol (FFC), os quais muitas vezes são ineficazes. Destes, somente o FFC é autorizado para tratar bacterioses em tilápia-do-Nilo, a espécie mais produzida no país. Este cenário nos levou a investigar a atividade antimicrobiana do tianfenicol (TAF) contra as principais bactérias patogênicas de peixes cultivados no Brasil. Foi determinada a concentração inibitória mínima (CIM) e a concentração bactericida mínima (CBM) do TAF para 49 cepas isoladas de surtos de bacteriose ocorridos no período 2011 a 2017 em três estados. Adicionalmente, avaliou-se a atividade antimicrobiana do TAF (G1: 10 mg/kg), do FFC (G2: 10 mg/kg) e da combinação do TAF com o FFC (G3: TAF+FFC: 5 + 2,5 mg/kg e G4: 2,5 + 1,25 mg/kg) no tratamento de aeromonose em tilápia-do-Nilo experimentalmente infectadas com Aeromonas hydrophila. Como resultado do estudo in vitro, mais da metade das cepas testadas foram sensíveis ao TAF, sendo que os gêneros Aeromonas, Lactococcus e Vibrio foram os mais sensíveis. No estudo in vivo, o TAF foi eficaz no ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Outbreaks of bacterial diseases in fish farm are unpredictable; therefore, it is necessary to have effective therapeutic options to reduce the morbidity and mortality. For effective therapy, the anticipated pharmacokinetics and antibacterial activity of the antimicrobial in the target fish species under the given conditions must be considered before decide which antimicrobial to use. In Brazil, only two antimicrobials are approved for use in aquaculture, oxytetracycline (OTC) and florfenicol (FFC), which are often innefective. Moreover, only FFC is approved for use to treat bacterial diseases in Nile tilapia, the main specie in Brazil. This scenario led us to investigate the antibacterial activity o thiamphenicol (TAP) against the main bacteria infecting fishes in Brazil. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of TAP were determined for 49 strains isolated from diseases outbreaks registered during 2011 - 2017 in three States. Additionally the antibacterial activity of TAP (10 mg kg-1), FFC (10 mg kg-1) and TAF combined with FFC (G3: TAF+FFC: 5 + 2.5 mg kg-1 e G4: 2.5 + 1.25 mg kg-1) against Aeromonas hydrophila in Nile tilapia aeromoniosi models were evaluated. More than half of the tested strains were in vitro sensitive to TAP, being TAP highly potent against Aeromonas, Lactococcus, and Vibrio. The in vivo therapy with TAP alone and combined with FFC was effective to treat aeromoniosis in Nile tilapia. Groups G1, G2, G3, G4 and co... (Complete abstract click electronic access below) / Mestre
217

Análise de parabenos em amostras de água de cultivo de tilápia do Nilo (Oreochromis niloticus) e efeitos em biomarcadores bioquímicos / Parabens analysis in water samples with nile tilapia (Oreochromis niloticus) and effects in biochemical biomarkers

Silva, Daniele Caetano da 13 July 2015 (has links)
Os parabenos utilizados como conservantes nas indústrias de cosméticos, alimentos e fármacos não são removidos por completo nas estações de tratamento de água e esgoto, além disso, podem causar danos a biota aquática. O presente estudo teve como finalidade aplicar um método analítico novo para quantificar o metil (MP), etil (EP), propil (PP), butil (BP), benzilparabeno (BzP) e a mistura (metil e propilparabeno) em amostras de água dos aquários com tilápias do Nilo (Oreochromis niloticus). A técnica analítica usada foi a cromatografia líquida com detector de arranjo de diodo (HPLC-DAD). Avaliou-se a toxicidade dos parabenos em tilápias e os efeitos nos biomarcadores bioquímicos dos animais após 6 e 12 dias dos testes de exposição e por administração via injeção intraperitoneal. A concentração dos parabenos utilizada em todos os testes foi de 4,0 mg L-1 (de cada parabeno individualmente) e de 6,0 mg L-1 do metil e de 1,7 mg L-1 do propilparabeno para a mistura. Foram feitas análises nos biomarcadores superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx), glutationa redutase (GR), glutationa reduzida(GSH-t) e peroxidação lipídica (MDA). O limite de detecção dos parabenos foi de 0,03 mg L-1 (MP e EP), 0,05 mg L-1 (PP) e 0,10 mg L-1 (BP e BzP), e o limite de quantificação foi de 0,13 mg L-1 (MP, EP, PP), 0,18 mg L-1 (BP) e 0,25 mg L-1 (BzP). Foi possível quantificar somente o PP e a mistura (MP + PP) nas amostras de água dos aquários que continham peixe, no máximo 30 h após a exposição. Nas amostras de água sem a presença dos peixes, foi possível quantificar o BP e a mistura, metil e propilparabeno, durante os 12 dias de exposição. Os testes de toxicidade mostraram que a concentração letal para 50% dos indivíduos após 48 h de exposição foi de 67,11 mg L-1 do MP, 24,08 mg L-1 do EP, 17,34 mg L-1 do PP, 7,98 mg L-1 do BzP e 7,80 mg L-1 do BP, sendo que estes dois últimos compostos podem ser considerados os mais tóxicos da classe. Outro modo de ação tóxica também observada dos parabenos foi a narcose, ou seja, a perda temporária da consciência e da mobilidade. À medida que aumenta o comprimento da cadeia, aumenta a lipofilicidade destas substâncias, que está relacionada com o coeficiente de partição octanol/água (Kow) das mesmas e consequentemente aumenta a toxicidade. Estes dados indicaram que quanto mais lipofílico mais tóxico é o composto. Relacionando as atividades enzimáticas testadas com os níveis de peroxidação lipídica, o metilparabeno foi o único composto capaz de provocar danos aos tecidos testados por meio das espécies reativas de oxigênio. Isso foi comprovado através da inibição da atividade das enzimas analisadas com o aumento nos níveis de MDA. Por outro lado, mesmo com as enzimas antioxidantes apresentando atividades elevadas isso não foi suficiente para impedir a redução nos níveis de GSH-t. Tais resultados indicam que os parabenos podem agir negativamente nas tilápias. / Parabens, used as preservatives in cosmetics, foodstuffs and pharmaceuticals are not completely removed from water in sewage treatments, which may cause damage to aquatic biota. The present study addresses a new methodology to measure the quantity of methyl (MP), ethyl (EP), propyl (PP), butyl (BP), benzyl (BzP) parabens and a mixture of methyl and propylparaben in water. Aquarium water of experiments with tilapia samples was analyzed for 12 days by liquid chromatography with a doide array detector (HPLC-DAD). The toxicity of parabens in Nile tilapia (Oreochromis niloticus) and its effects on biochemical biomarkers were also evaluated after 6 and 12 days of exposure and intraperitoneal injection. The concentrations of parabens used in all tests were 4.0 mg L-1 (alone) and to mixture was 6.0 mg L-1 of methyl and 1.7 mg L-1 of propylparaben. Biomarkers, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione reduced (GSH-t) and lipid peroxidation (MDA) were analyzed. The results show the detection limits for the analysis of parabens were 0.03 mg L-1 (MP and EP), 0.05 mg L-1 (PP) and 0.10 mg L-1 (BP and BzP), and the quantification limits were 0.13 mg L-1 (MP, EP, PP), 0.18 mg L-1 (BP) and 0.25 mg L-1 (BzP). In the water sample with fish, the compounds PP and the mixture (MP + PP) could be quantified up to 30h after exposure. In the water sample without fish, the compounds BP and the mixture were quantified for 12 days of exposure. Toxicity test revealed the lethal concentrations for 50% of individuals after 48 h of exposure were 67.11 mg L-1 for MP, 24.08 mg L-1 for EP, 17.34 mg L-1 for PP, 7.98 mg L-1 for BzP and 7.80 mg L-1 for BP. Therefore, BzP and BP can be considered the most toxic of the class. As the chain length grows, the lipophilicity of the substances increases. Such an increase is related to their octanol/water (Kow) partition coefficient and, consequently, increases toxicity. Another toxic action observed for the parabens was the temporary loss of consciousness and mobility of the organisms. According to the enzymatic activity tested and the lipid peroxidation levels, the methylparaben was the only compound that caused damage by reative oxidative species, supported by the inhibition of the activities of the enzymes and the increase in the MDA levels. However, the high activity of the antioxidant enzymes to exposure and intraperitoneal injections could not prevent the reduction in the levels of GSH-t. Such results indicate parabens can cause negative effects on tilapia.
218

Heavy metal contamination and metallothionein mRNA levels in the tissues of tilapia.

January 1998 (has links)
Lam Kwok Lim. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 107-126). / Abstract also in Chinese. / Acknowledgments --- p.i / Presentations Derived from the Present Thesis Work --- p.ii / Abstract --- p.iv / Abbreviations --- p.vii / Abbreviation Table for Amino Acids --- p.ix / List of Figures --- p.x / List of Tables --- p.xii / Contents --- p.xiii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Metallothionein (MT) --- p.1 / Chapter 1.1.1 --- Classification of MT --- p.1 / Chapter 1.1.2 --- Structure of MT --- p.2 / Chapter 1.1.3. --- Structure of MT Genes --- p.4 / Chapter 1.1.4 --- Function of MT --- p.5 / Chapter 1.1.5 --- Regulation of MT Expression --- p.7 / Chapter 1.1.6 --- Fish MT --- p.9 / Chapter 1.1.7. --- Aims and Rationale of the Present Study --- p.12 / Chapter 2 --- MT mRNA Induction of Tilapia After Intraperitoneal Injection of Metal --- p.18 / Chapter 2.1 --- Introduction --- p.18 / Chapter 2.1.1. --- Specific Aims of This Chapter --- p.19 / Chapter 2.2 --- Materials and Methods --- p.20 / Chapter 2.2.1 --- Regents --- p.20 / Chapter 2.2.1.1 --- Purification of Total RNA --- p.20 / Chapter 2.2.1.2 --- Denaturing Gel and Vacuum Blotting of RNA (Northern Blotting) --- p.20 / Chapter 2.2.1.3 --- Hybridization --- p.21 / Chapter 2.2.2 --- Methods --- p.21 / Chapter 2.2.2.1 --- Purification of Total RNA --- p.21 / Chapter 2.2.2.2 --- Vacuum Blotting of Total RNA (Northern Blotting) --- p.22 / Chapter 2.2.2.3 --- Radioactive Labeling of Nucleic Acid Probes --- p.22 / Chapter 2.2.2.4 --- Hybridization --- p.22 / Chapter 2.2.2.5 --- Densitometric Analysis --- p.23 / Chapter 2.2.2.6 --- Calculation of MT mRNA Levels and Analysis of Results --- p.23 / Chapter 2.2.3 --- Endogenous MT mRNA Expression of Juvenile Tilapia and Carp --- p.23 / Chapter 2.2.4 --- Induction of MT mRNA Juvenile Tilapia and Carp Injected with Metals --- p.24 / Chapter 2.3 --- Results --- p.25 / Chapter 2.3.1 --- Endogenous Levels of MT mRNA in Tilapias in Normal Conditions --- p.25 / Chapter 2.3.2 --- Induction of MT mRNA Levels in Juvenile Tilapia Injected with Metals --- p.25 / Chapter 2.3.1.1 --- Copper Injection --- p.25 / Chapter 2.3.1.2 --- Zinc Injection --- p.25 / Chapter 2.3.1.3 --- Cadmium Injection --- p.26 / Chapter 2.3.3 --- Induction of MT mRNA Levels in Juvenile Carp with Zinc Injection --- p.26 / Chapter 2.4 --- Discussion --- p.26 / Chapter 2.4.1 --- MT mRNA Expression of Tilapia and Carp Injected with Metals --- p.26 / Chapter 2.5 --- Conclusions --- p.29 / Chapter 3 --- Induction Level of MT mRNA in Tilapia After Aqueous Exposure to Metals --- p.35 / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.1.1 --- Specific aims of this chapter --- p.36 / Chapter 3.2 --- Material s and Methods --- p.36 / Chapter 3.2.1 --- 96hours LC-50 values for zinc and copper --- p.36 / Chapter 3.2.2 --- Induction of MT mRNA in Juvenile Tiapias under Metal Aqueous Exposures --- p.37 / Chapter 3.2.3 --- Calculation of Fold Induction of MT mRNA and Analysis of Results --- p.38 / Chapter 3.2.4 --- Metal Analysis --- p.38 / Chapter 3.3 --- Results --- p.38 / Chapter 3.3.1 --- LC-50 values of metals for Juvenile Tilapia --- p.38 / Chapter 3.3.2 --- Induction of MT mRNA in Juvenile Tilapia under Metal Aqueous Exposures --- p.39 / Chapter 3.3.2.1 --- Aqueous Exposure to Copper --- p.39 / Chapter 3.3.2.2 --- Aqueous Exposure to Zinc --- p.40 / Chapter 3.3.2.3 --- Aqueous Exposure to Cadmium --- p.41 / Chapter 3.3.3 --- Induction of MT mRNA in Juvenile Carp after Aqueous Exposures to Metal --- p.41 / Chapter 3.3.3.1 --- Aqueous Exposure to Cadmium --- p.41 / Chapter 3.3.4 --- Metal Concentrations of Water Samples from the Aquaria in the Metal Exposure Test of Tilapia and Carp --- p.42 / Chapter 3.4 --- Discussion --- p.42 / Chapter 3.4.1 --- LC-50 values of Metals for Tilapia --- p.42 / Chapter 3.4.2 --- MT mRNA Expression of Tilapias under Metal Aqueous Exposure --- p.44 / Chapter 3.4.3 --- Normalization of the Signals of Northern Blot Analysis --- p.47 / Chapter 3.5 --- Conclusions --- p.48 / Chapter 4 --- Field Study --- p.58 / Chapter 4.1 --- Introduction --- p.58 / Chapter 4.1.1 --- Specific Aims of this Chapter --- p.59 / Chapter 4.2 --- Materials and Methods --- p.59 / Chapter 4.2.1 --- Sampling Sites --- p.59 / Chapter 4.2.2 --- Data Analysis --- p.60 / Chapter 4.2.3 --- Harvest of Feral Tilapia --- p.60 / Chapter 4.2.4 --- Determination of Metal Concentration of Metal Concentration in the Tissues of Feral Tilapia --- p.60 / Chapter 4.2.5 --- Endogenous MT mRNA Levels Using Northern Blot Analysis --- p.61 / Chapter 4.2.6 --- Calculation of MT mRNA Levels and Analysis of Results --- p.61 / Chapter 4.3 --- Results --- p.62 / Chapter 4.3.1 --- Metal Concentrations in the Tissues of Feral Tilapia --- p.62 / Chapter 4.3.2 --- Comparison of Metal Concentrations Among Different Tissues of Feral Tilapia --- p.62 / Chapter 4.3.3 --- MT mRNA Levels in the Tissues of Feral Tilapia --- p.63 / Chapter 4.3.4 --- Correlation Between Metal Concentrations and Endogenous MT mRNA Levels in the Tissues of Feral Tilapia --- p.63 / Chapter 4.4 --- Discussion --- p.64 / Chapter 4.4.1 --- Bioaccumulation of Metals --- p.64 / Chapter 4.4.2 --- Endogenous Levels of MT mRNA in the Feral Tilapia --- p.67 / Chapter 4.5 --- Conclusions --- p.68 / Chapter 5 --- Cloning of Tilapia MT Genes --- p.86 / Chapter 5.1 --- Specific Aims of This Chapter 、 --- p.86 / Chapter 5.2 --- Materials and Methods --- p.87 / Chapter 5.2.1 --- Regents --- p.87 / Chapter 5.2.1.1 --- Preparation of Plasmid DNA --- p.87 / Chapter 5.2.1.2 --- Preparation of Genomic DNA --- p.87 / Chapter 5.2.1.3 --- Restriction Enzyme Digestion --- p.88 / Chapter 5.2.1.4 --- Vacuum Blotting of DNA (Southern Blotting) --- p.88 / Chapter 5.2.1.5 --- Polymerase Chain Reaction --- p.89 / Chapter 5.2.1.6 --- Transformation of E.coli Competent Cells --- p.89 / Chapter 5.2.1.7 --- Nucleotide Sequence Determination --- p.89 / Chapter 5.2.1.8 --- List of Primers --- p.90 / Chapter 5.2.1.8.1 --- Primers for Nucleotide Sequence Determination --- p.90 / Chapter 5.2.1.8.2 --- Tilapia MT Specific Primers for PCR --- p.90 / Chapter 5.2.2 --- Methods --- p.91 / Chapter 5.2.2.1 --- Preparation of Plasmid --- p.91 / Chapter 5.2.2.2 --- Preparation of Genomic DNA --- p.91 / Chapter 5.2.2.3 --- Preparation of Enzyme Digestion --- p.92 / Chapter 5.2.2.4 --- Vacuum Blotting of Genomic DNA (Southern Blotting) --- p.92 / Chapter 5.2.2.5 --- Radioactive Labeling of Nucleic Acid Probes --- p.92 / Chapter 5.2.2.6 --- Hybridization --- p.93 / Chapter 5.2.2.7 --- Polymerase Chain Reaction --- p.93 / Chapter 5.2.3 --- Southern Blot Analysis of Tilapia Genomic DNA --- p.93 / Chapter 5.2.4 --- Analysis of the Sequences of Tilapia MT Genes --- p.94 / Chapter 5.2.4.1 --- Amplification of MT Genes Using PCR --- p.94 / Chapter 5.2.4.2 --- Cloning of the MT Genes --- p.94 / Chapter 5.2.4.3 --- Transformation of E.coli Competent Cell --- p.94 / Chapter 5.2.4.4 --- Nucleotide Sequence Determination --- p.95 / Chapter 5.3 --- Results --- p.95 / Chapter 5.3.1 --- Southern Blot Analysis of Tilapia Genomic DNA --- p.95 / Chapter 5.3.2 --- Amplification of MT Gene Fragments Using PCR --- p.95 / Chapter 5.3.3 --- Analysis of the Sequences of Tilapia MT Genes --- p.96 / Chapter 5.4 --- Discussion --- p.96 / Chapter 5.4.1 --- Fish MT Genes --- p.96 / Chapter 5.5 --- Conclusions --- p.98 / Chapter 6 --- General Discussion --- p.104 / References --- p.107
219

Eficácia terapêutica, segurança clínica e ecotoxicológico da fosfomicina em tilápias, Oreochromis niloticus, com aeromonose e estreptococose /

Barbuio, Roberto. January 2017 (has links)
Orientador: Marco Antonio de Andrade Belo / Coorientador: Claudinei da Cruz / Banca: Silvia Patrícia Carraschi de Oliveira / Banca: Wilson Gomez Manrique / Banca: Eduardo Makoto Onaka / Banca: Annelise Carla Camplesi dos Santos / Resumo: O presente estudo teve por objetivos avaliar a eficácia terapêutica a segurança clínica e ecotoxicológica do antimicrobiano fosfomicina para o tratamento de aeromonose e streptococose em tilápia do Nilo (Oreochromis niloticus). Para tal, a segurança clínica foi avaliada com as doses de 10, 20 e 40 mg de fosfomicina.kg-1; os estudos de eficácia com a dose terapêutica de 10 mg de fosfomicina.kg-1, foram conduzidos com peixes desafiados com Aeromonas hydrophila e Streptococcus agalactiae; os ensaios de ecotoxicidade foram feitos para a determinação de CL50 em peixes (O. niloticus) e plantas aquáticas (Lemna minor) e de CE50 para crustáceos (Daphnia magna) e moluscos (Pomacea canaliculata). Nos estudos foram utilizadas tilápias de 112g ± 5,6g, acondicionadas em tanques de 400 L (n=10). Ambos os estudos de eficácia terapêutica com 10 mg.kg-1 demonstraram a eficácia para A. hydrophila e S. agalactiae, pois nas análises de reisolamento destes microrganismos não ocorreu crescimento dos mesmos em amostras de fígado, rim, baço e cérebro dos peixes tratados quando comparados aos grupos infectados e não tratados nos quais o número de unidades formadoras de colônias (UFC) foi de 7,6 ± 2,4 por placa. Na infecção por A. hydrophila apresentaram microcitose e linfopenia, assim como, trombocitose na fase inicial da infecção seguida de trombocitopenia. Lesões nos tecidos hepáticos e renais corroboraram as alterações da atividade enzimática sérica de ALT, AST, FA e nos níveis de creatinina, cole... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study aimed to evaluate the therapeutic efficacy of clinical and ecotoxicological safety of antimicrobial fosfomycin for the treatment of aeromonose and streptococcosis in Nile tilapia (Oreochromis niloticus). For this, clinical safety was evaluated with doses of 10, 20 and 40 mg of fosfomycin.kg-1; Efficacy studies with the therapeutic dose of 10 mg of fosfomycin.kg-1 were conducted with fish challenged with Aeromonas hydrophila and Streptococcus agalactiae; The ecotoxicity assays were performed for the determination of LC50 in fish (O. niloticus) and aquatic plants (Lemna minor) and EC50 for crustaceans (Daphnia magna) and molluscs (Pomacea canaliculata). In the studies, tilapia of 112 g ± 5.6 g were used, packed in 400 L tanks (n = 10). Both therapeutic efficacy studies with 10 mg.kg-1 demonstrated efficacy for A. hydrophila and S. agalactiae, because in the reisolation analyzes of these microorganisms there was no growth in liver, kidney, spleen and brain samples of treated fish, While in the infected and untreated groups, mean growth was greater than ten colony forming units (CFU) per plaque. In the A. hydrophila infection they presented microcytosis and lymphopenia, as well as thrombocytosis in the initial phase of infection followed by thrombocytopenia. Liver and renal tissue damage corroborated the changes in serum enzyme activity of ALT, AST, FA and creatinine, cholesterol and triglyceride levels. In S. agalactiae infection, there was a decrease in the n... (Complete abstract click electronic access below) / Doutor
220

Aclimação e desempenho de tilápias (Oreochromis sp.) em sistema de recirculação de água do mar /

Ostini, Sérgio. January 2002 (has links)
Orientador: Newton Castagnolli / Banca: Dalton José Carneiro / Banca: João Donato Scorvo Filho / Banca: José Eurico Possebon Cyrino / Banca: Teresa Cristina Ribeiro Dias / Resumo: Alevinos de tilápia vermelha foram transferidos diretamente da água doce (0‰) para água do mar (35‰), e também submetidos a dois diferentes sistemas gradativos de aclimação: aumento gradual de salinidade em 5‰ a cada dia e, aumentos de 5‰ a cada dois dias. O estudo foi conduzido no Setor de Carcinicultura do Centro de Aqüicultura da Universidade Estadual Paulista (CAUNESP), Jaboticabal, SP. Três diferentes tamanhos de alevinos de tilápia vermelha foram testados: tratamento 1 - animais com 18,50 ± 1,2 mm; tratamento 2 - 49,33 ± 4,45 mm; tratamento 3 - 71,97 ± 5,7 mm respectivamente. Grupos de 10 animais (n = 3) de cada classe de tamanho foram transferidos diretamente da água doce para água do mar em aquários de 10 litros, aerados, e mantidos a 26ºC e com salinidade de 35‰, A mortalidade foi avaliada em intervalos de 15 minutos. Para aclimação gradativa, 25 animais por parcela (n = 3) foram mantidos em tanques cilíndrico-cônicos de 100 L equipados com filtro mecânico de 40 L com substrato de conchas marinhas. Os peixes foram alimentados duas vezes ao dia, sendo a temperatura, salinidade e mortalidade avaliadas diariamente. Os experimentos tiveram duração de 20 dias cada, e 20% dos indivíduos sobreviventes foram submetidos à biometria. Os dados foram analisados segundo delineamento fatorial 3 x 2. Os resultados demonstraram não haver sobrevivência da tilápia vermelha, quando transferida diretamente da água doce para a água do mar, para todos os tamanhos estudados. Os sistemas de aclimação demonstram a viabilidade de aclimação gradativa de alevinos de tilápia vermelha em todos os tamanhos testados, porém, a maior taxa de sobrevivência foi obtida com alevinos com comprimento padrão médio ³ a 49,3 mm e aumento de salinidade de 5‰.dia- 1, Os animais apresentaram melhores condições corporais quando aclimados mais lentamente (5‰ 2 dias-1) / Abstract: Red tilapia fingerlings were either directly transferred from freshwater to sea water (35‰) and also submitted to two different systems of gradual acclimation: daily increasing of 5‰ and the same gradual increment every two days. The study was set up at the Freshwater Prawn Laboratory, classes Aquaculture Center of the UNESP, Jaboticabal, SP. Three different size of red tilapia fingerlings were used: Trial 1 - 18.5 ± 1.2 mm, Trial 2 - 49.33 ± 4.45mm and Trial 3 - 71.9 ± 5.7 mm, respectively. Groups of 10 animals (n = 3) of each class were directly transferred to sea water in 10 L aquarium and maintained at 26oC, 35‰ salinity, and mortality were recorded every 15 minutes. For the gradual acclimation, 25 fish per parcel (n = 3) of each treatment were stocked in 100 L, conic-cylindrical tanks equipped with mechanical filter (40 L) made out of marine shell substrate. Fish were fed twice a day and water salinity and temperature and mortality were recorded every day. The experiment lasted for 20 days, 20% of the remained fish were weighed and data were analyzed through a 3 x 2 factorial. Results show that the tolerance of red tilapia to direct transfer to sea water increases with size until a certain extent, and that viability of a gradual acclimation to marine water as satisfactory for all tested class sizes but better survival rates were obtained with fingerlings measuring 49.3 mm total length, with a daily increase in salinity of 5‰. Better condition factor was presented by animals acclimated with 5‰ increase every two days / Doutor

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