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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.
131

Examination of the signalling properties and ligand-binding potential of stimulatory leukocyte immune-type receptors (IpLITRs) in the channel catfish (Ictalurus punctatus)

Mewes-Ares, Jacqueline Unknown Date
No description available.
132

The morphology and function of the peritoneum in lower vertebrates with special reference to teleosts

Lewis, Philip Nigel January 2001 (has links)
No description available.
133

Selected population characteristics of channel catfish, Ictalurus punctatus, and flathead catfish, Pylodictis olivaris, in the lower 200 miles of the Wabash River

Willenberg, Zachary J. January 2000 (has links)
This study describes the population characteristics of channel catfish (Ictalurus punctatus) and flathead catfish (Pylodictis olivaris) in the lower 200 miles of the Wabash River in 1998. Densities of channel and flathead catfish did not differ over the study reach for either species. Electrofishing captured twice as many channel as flathead catfish, and hoop nets captured twice as many flatheads as channel catfish. Growth rates of channel catfish were fast as compared to documented growth in other rivers in the United States, with ages ranging from 1-8. Flathead catfish growth was average when compared to that reported in other United States rivers with ages ranging from 0-7. Length-frequency analysis for both species revealed the populations were comprised of small individuals with mortality higher than expected in older fish. This study will aid in the management of the Wabash River, as historic data are limited. / Department of Biology
134

Dietary protein and energy interactions in African catfish Clarias gariepinus (Burchell, 1822)

Ali, Md. Zulfikar January 2001 (has links)
In order to investigate the interactions of dietary protein and energy and their utilisation by African catfish, Clarias gariepinus (Burchell, 1822) (12.43 ± 0.05 g), a series of four nutritional experiments (triplicate groups of 20 fish per 30-L tank at 28 ± 1°C, for 8 weeks) were carried out using fish meal based diets. Optimum dietary protein to energy ratio (P/E ratio) and optimum lipid to carbohydrate ratio (L/CHO ratio) were investigated. Based on optimised dietary P/E ratio and L/CHO ratio, optimum feeding regime and compensatory growth were also investigated in this species. In the experiments to optimise P/E ratio and L/CHO ratio fish were offered each diet at 5% of their body weight per day adjusted fortnightly. In the optimum feeding regime experiments, fish were offered each diet to appetite or to a restricted level. The restricted regimes were achieved by offering fish decreasing fixed feeding rates with increasing dietary protein level. Studies on compensatory growth were conducted in two phases each of 4 weeks. In the first phase, triplicate groups of 30 fish and in the second phase triplicate groups of 20 fish (per 30-L tank) were offered the diet in six mixed feeding schedules at two feeding regimes i.e. appetite and restricted. The restricted regime was achieved by offering fish 1% (maintenance ration) of their body weight per day adjusted after fortnightly weighing. Optimum dietary P/E and L/CHO ratios were 20.54-mg protein/kJ of GE and 0.40 g/g respectively, with a crude protein level over 40% and gross energy of more than 20 kJ/g GE. The results of investigating feeding regimes suggest that dietary protein level could be reduced from over 40% to 35% by feeding to appetite based on the above optimised dietary P/E and L/CHO ratios. Addition of dietary energy as lipid at varying protein levels resulted in increased growth, protein and energy utilisation in C. gariepinus. Based on optimised dietary P/E ratio, dietary carbohydrate levels were increased (with concomitant reduction in dietary lipid levels) resulting in a trend towards higher growth performance, protein and energy utilisation. Protein and energy utilisation did not vary (P > 0.05) with feeding regime or dietary protein level. C. gariepinus showed partial compensatory growth under alternating periods of feeding a restricted (maintenance requirements) and appetite ration and also showed higher feed, protein, lipid and energy utilisation efficiencies in comparison to appetite feeding.Increase in dietary lipid produced an increment in carcass lipid deposition, both in whole body and liver in all studies. Fish in all treatments did not show significant differences (P < 0.05) in body protein content. Optimum P/E ratio studies, with varying dietary protein and energy level, produced higher liver glycogen, plasma glucose and plasma triglycerides at higher dietary carbohydrate level with lower protein diets. In the studies to optimise lipid to CHO ratio comparatively lower (P < 0.05) plasma glucose and plasma cholesterol deposition were observed while no consistent trends were found in liver glycogen deposition in fish fed higher dietary lipid with concomitant lower CHO levels. Studies on optimising feeding regime, with varying protein levels, did not show any significant differences (P < 0.05) in liver glycogen, plasma glucose, plasma triglycerides and plasma cholesterol in response to dietary treatment. In all studies fish fed the experimental diets showed insignificant differences (P > 0.05) in plasma amino acid levels and digestive enzyme activities (protease and lipase) while intestinal a-amylase activity increased with increasing dietary carbohydrate level. Histological examination of intestine & liver in all studies showed no abnormalities. In conclusion, these studies suggest that manipulation and optimisation of dietary protein and energy intakes plays a very significant role in African catfish, Clarias gariepinus nutrition.
135

Hormonálně indukovaný umělý výtěr jikernaček sumce velkého (Silurus glanis) / Hormonal induction of artificial stripping of the female European catfish (Silurus glanis)

BORKOVEC, Tomáš January 2010 (has links)
The optimalization way of hormonal induction ovulation females European catfish Silurus glanis was the aim of experiment with the help of hormonal preparate on the base functional of the analogue GnRH. Fish with females were fish out in the ponds early in june and injected by hormonal preparates CPE, Dagin and Ovopel. Was monitoring latency time in dependency of water temperature, percent of ovulated females, relative weight of ovulated eggs, fertilization eggs and hatching performance.
136

Study of Edwardsiella ictaluri Conserved Genes Towards the Development of an Attenuated Recombinant Vaccine for Fish Host

January 2012 (has links)
abstract: Teleosts have the most primitive adaptive immune system. However, in terms of functionality the teleost immune system is similar to birds and mammals. On the other hand, enteric bacterial pathogens of mammals and birds present conserved regulatory mechanisms that control virulence factors. In this context, deletion of conserved genes that control virulence factors have been successfully used as measure to construct live attenuated bacterial vaccines for mammals and birds. Here, I hypothesize that evolutionary conserved genes, which control virulence factors or are essential for bacterial physiology in Enterobacteriaceae, could be used as universal tools to design live attenuated recombinant bacterial vaccines from fish to mammals. The evolutionary conserved genes that control virulence factors, crp and fur, and the essential gene for the synthesis of the cell wall, asd, were studied in Edwardsiella ictaluri to develop a live recombinant vaccine for fish host. The genus Edwardsiella is one of the most ancient represent of the Enterobacteriaceae family. E. ictaluri, a host restricted pathogen of catfish (Ictalurus punctatus), is the causative agent of the enteric septicemia and one of the most important pathogens of this fish aquaculture. Although, crp and fur control different virulence factors in Edwardsiella, in comparison to other enterics, individual deletion of these genes triggered protective immune response at the systemic and mucosal level of the fish. Deletion of asdA gene allowed the creation of a balanced-lethal system to syntheses heterologous antigens. I concluded that crp, fur and asd could be universally used to develop live attenuate recombinant Enterobacteriaceae base vaccines for different hosts. / Dissertation/Thesis / Ph.D. Microbiology 2012
137

Revisão taxonômica de Heptapterus mustelinus (Valenciennes, 1835) (Siluriformes: Heptapteridae)

Fuster, Dario Ruben Faustino January 2017 (has links)
As populações de Heptapterus mustelinus do rio Uruguai, sistema da Laguna dos Patos e os rios dos sistemas costeiros do sul do Brasil e Uruguai foram revisados com dados morfológicos e moleculares. Duas novas espécies de Heptapterus foram reconhecidas. Heptapterus sp.n.A com distribuição restrita para o rio Pelotas na bacia do alto rio Uruguai. Heptapterus sp.n.B endêmica de tributários do rio Ibicuí na bacia do baixo rio Uruguai. As novas espécies distinguem-se do seu congênere mais próximo H. mustelinus pelo menor número de vértebras. Dados morfométricos e moleculares são congruentes no reconhecimento das duas espécies novas. / The populations of Heptapterus mustelinus from the Uruguay River, laguna dos Patos system and the coastal streams of southern Brazil were reviewed with morphological and molecular data. Two new species of Heptapterus were recognized. Heptapterus sp.n.A with a restricted distribution to rio Pelotas, in the upper Uruguay River basin. Heptapterus sp.n.B endemic to tributaries of rio Ibicuí, in the lower Uruguay River basin. The new species are distinguished from its closest congener H. mustelinus by the lower number of vertebrae. Morphometric and molecular data are congruent to recognize the two new species.
138

Vliv teploty na udržení schopnosti oplození a líhnivosti při přechovávání neoplozených jiker u keříčkovce červenolemého

BORŮVKA, Vít January 2017 (has links)
When hormonally induced artificial spawning of african catfish (Clarias gariepinus), was several female injected intraperitoneally in one dose preparation Ovopel at doses of 1.5 pellet × kg-1. Females were kept separately in the tanks at a temperature of 21.5 °C. All females were spawned at the same time latency 19.2 hours. Eggs from three spawned females were mixed and divided into 6 doses. Each batch was placed into thermoboxes at temperature 5 °C, 10 °C, 15 °C, 20 °C, 25 °C and 30 °C. These eggs were stored in thermoboxes and after times of storage 0.5 h, 1 h, 1.5 h, 2 h, 3 h, 4 h, 6 h, 8 h, 10h, part of the eggs (approximately 50 to 100 pieces) were taken out from each thermoboxes in three replications and was placed into individuals cups and fertilized by adding 5 drops of sperm and 20 ml of water. In these samples were subsequently observed fertilization, hatching rate and survival rate. When watching fertilization was in individual temperature the highest values and also statistically non-significant difference ( = 0.05) achieved: at 5 °C in times of fertilization 0.5 2 hrs. (61.6 +- 5.81 % - 47.7 +- 1.48 %), at 10 °C in times 0.5 - 1.5 hrs. (70 +- 6.7 % - 62.1 +- 8.9 %), at 15 °C in times 0.5 - 3 hrs. (59.6 +- 9.4 % - 59.6 +- 2.9 %), at 20 °C in times 0.5 - 3 hrs. (61.4 +- 3.6 % - 56.1 +- 2.5 %), at 25 °C in times 0.5 - 4 hrs. (55.5 +- 7.2 % - 49.7 +- 9.3 %) and at 30 °C in times 0,5 - 3 hrs. (61.6 +- 10.3 % - 51.8 +- 17.8 %). When watching hatching rate was in individual temperature the highest values and also statistically non-significant difference ( = 0.05) achieved: at 5 °C in times of fertilization 0.5 - 1 hrs. (28.4 +- 2.9 % - 21.1 +- 9.5 %), at 10 °C in times 0.5 - 1 hrs. (36.6 +- 17.3 % - 22.1 +- 7 %), at 15 °C in times 0.5 - 2 hrs. (34.1 +- 5.5 % - 26.9 +- 5.1 %), at 20 °C in times 0.5 - 2 hrs. (33 +- 8.2 % - 28.8 +- 1.6 %), at 25 °C in times 0.5 - 4 hrs. (31.4 +- 6.2 % - 15.3 +- 13.5 %) and at 30 °C in times 0.5 - 2 hrs. (33.1 +- 9.2 % - 21.2 +- 8 %). When watching survival rate was in individual temperature the highest values and also statistically non-significant difference ( = 0.05) achieved: at 5 °C in times of fertilization 0.5 - 1 hrs. (20.1 +- 6 % - 13 +- 3.3 %), at 10 °C in times 0.5 - 3 hrs. (19.8 +- 15.31 % - 3.1 +- 3 %), at 15 °C in times 0.5 - 6 hrs. (23.3 +- 9 % - 5 +- 2.8 %), at 20 °C in times 0.5 - 2 hrs. (22.4 +- 1.9 % - 15.1 +- 5.2 %), at 25 °C in times 0.5 - 4 hrs. (18.7 +- 4.4 % - 4.1 +- 1.9 %) and at 30 °C in times 0.5 - 1.5 hrs. (26.2 +- 5.5 % - 21.4 +- 6.8 %). Suitable temperatures for the storage of unfertilized eggs after spawning are two hours before fertilization at temperatures from 15 to 30 °C. Other suitable temperatures which are useful for storage are temperatures 15 to 25 °C, for preservation after 3 hrs. and longer after fertilization.
139

Tracking blue catfish: quantifying system-wide distribution of a mobile fish predator throughout a large heterogeneous reservoir

Gerber, Kayla M. January 1900 (has links)
Master of Science / Division of Biology / Martha E. Mather / A flexible distribution is an adaptive response that allows animals to take advantage of spatial variation in the fluctuation of resources. Distribution of mobile organisms is complex so multi-metric patterns derived from dynamic distribution trajectories must be deconstructed into simpler components for both individuals and populations. Tagging and tracking fish is a very useful approach for addressing these fisheries research questions, but methodological challenges impede its effectiveness as a research tool. Here, I developed and evaluated a high-retention, high-survival tagging methodology for catfish. Then, I integrated multiple distribution metrics to identify if sites within an ecosystem function differently for mobile predators. Finally, I determined if distinct groups of individuals existed, based on distributional patterns. In the appendices, I test sources of variation in system-wide detections (i.e., season, diel period, size, and release location) and provide additional details on methods and interpretation of the results. To address these objectives, I tracked 123 acoustically tagged (VEMCO V9-V13) Blue Catfish (Ictalurus furcatus mean: 505.3 mm TL; SE: 12.3 mm; range: 300-1090 mm) from June through November, 2012-2013, in Milford Reservoir, KS. Across the five months, 85.4-100.0% of the tagged Blue Catfish were detected at least once a month by an array of 20 stationary receivers (VR2W), a detection rate much higher than rates reported in the literature for catfish (38%). Blue Catfish were consistently aggregated in the northern portion of the middle region of Milford Reservoir. Using three metrics (population proportion, residence time, and movements), I found four types of functional sites that included locations with (i) large, active aggregations, (ii) exploratory/transitory functions, (iii) small, sedentary aggregations, and (iv) low use. I also found that tagged Blue Catfish clustered into three groups of individuals based on distribution. These included (1) seasonal movers, (2) consistent aggregations across seasons, and (3) fish exhibiting site fidelity to Madison Creek. Sites with different functions and groups of individual fish were related but not the same. My approach to looking at multiple responses, functions of sites, and individual groupings provided new insights into fish ecology that can advance fisheries management of mobile predators.
140

Revisão taxonômica de Heptapterus mustelinus (Valenciennes, 1835) (Siluriformes: Heptapteridae)

Fuster, Dario Ruben Faustino January 2017 (has links)
As populações de Heptapterus mustelinus do rio Uruguai, sistema da Laguna dos Patos e os rios dos sistemas costeiros do sul do Brasil e Uruguai foram revisados com dados morfológicos e moleculares. Duas novas espécies de Heptapterus foram reconhecidas. Heptapterus sp.n.A com distribuição restrita para o rio Pelotas na bacia do alto rio Uruguai. Heptapterus sp.n.B endêmica de tributários do rio Ibicuí na bacia do baixo rio Uruguai. As novas espécies distinguem-se do seu congênere mais próximo H. mustelinus pelo menor número de vértebras. Dados morfométricos e moleculares são congruentes no reconhecimento das duas espécies novas. / The populations of Heptapterus mustelinus from the Uruguay River, laguna dos Patos system and the coastal streams of southern Brazil were reviewed with morphological and molecular data. Two new species of Heptapterus were recognized. Heptapterus sp.n.A with a restricted distribution to rio Pelotas, in the upper Uruguay River basin. Heptapterus sp.n.B endemic to tributaries of rio Ibicuí, in the lower Uruguay River basin. The new species are distinguished from its closest congener H. mustelinus by the lower number of vertebrae. Morphometric and molecular data are congruent to recognize the two new species.

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