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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.
261

Energy Reserves in Native Freshwater Mussels (Bivalvia:Unionidae) with and without Attached Zebra Mussels: Effects of Food Deprivation

Patterson, Matthew Alan 16 June 1998 (has links)
This project evaluated the feasibility of salvaging zebra mussel-infested freshwater mussels from their native habitat by determining 1) how zebra mussel infestation affects unionid feeding and body condition, 2) how starvation in quarantine affects body condition of unionids, and 3) what feeding regime maintain unionid condition in quarantine. The effects of zebra mussel infestation on two mussel species were evaluated through glycogen analyses of mantle tissue and gut content analysis. Specimens of Amblema p. plicata (Say, 1817) and Quadrula p. pustulosa (I. Lea, 1831), collected from a heavily infested reach of the Ohio River in 1996, had significantly lower (p<0.05) glycogen levels than specimens collected from a low-infestation reach upstream. In 1996 and 1997, heavily infested Amblema p. plicata and Quadrula p. pustulosa had significantly less (p<0.01) organic matter and fewer algal cells in their guts than lightly infested specimens. In addition, gut contents of individual A. p. plicata contained significantly less (p<0.05) organic matter and fewer algal cells than the combined gut contents of all zebra mussels (18-33 mm in length) attached to their shells. Gut analyses also revealed significant diet overlap between native unionids and infesting zebra mussels. Thus, competitive interactions or interference by zebra mussels likely reduced unionid ingestion and consequently reduced glycogen stores. During quarantine, unionids salvaged from a lightly infested area and starved for 30 days had glycogen levels that declined dramatically. After 30 days without supplemental feeding, mean glycogen levels of A. p. plicata declined 85%, and mean glycogen levels of Q. p. pustulosa declined 70%. Thus, feeding of unionids is necessary to maintain their condition during lengthy quarantine. To determine the best feeding regime for unionids in quarantine, assimilation efficiencies and carbon budgets were established for the rainbow mussel, Villosa iris (Lea, 1829), using radio-labelled cultures of Neochloris oleoabundans (Chantanachat and Bold 1962) at three cell concentrations. Assimilation efficiencies for Villosa iris at 100,000cells/ml, 10,000 cells/ml, and 1,000 cells/ml were similar (45-56%); however, regardless of these similarities, assimilation efficiencies from this study indicate that Neochloris oleoabundans is readily assimilated (~50% AE) by Villosa iris . In addition, total assimilation was maximized at 100,000cells/ml, which indicates that Villosa iris has the greatest amount of energy available for growth, reproduction, and maintenance of condition in captivity at this cell concentration. During a second quarantine experiment, specimens were provided with 100,000cells/ml of N. oleoabundans twice per day. Initial mean glycogen levels for Amblema p. plicata (9.4 + 2.4 mg/g) and Quadrula p. pustulosa collected from ORM 175.5 in July 1997 were not significantly different (p>0.3) than the mean glycogen levels of A. p. plicata and Q. p. pustulosa collected from the same site in July 1996. Glycogen stores of unionids entering quarantine, therefore, were similar in both the starvation and controlled feeding experiments. After 7, 14, and 30 days of controlled feeding in quarantine, mean glycogen levels of A. p. plicata and Q. p. pustulosa did not change significantly (p>0.1). Thus, quarantine protocol for salvaged native mussels should include the feeding of algae to captive specimens to sustain glycogen levels prior to relocation. / Master of Science
262

Developmental axial skeletal deformities : baseline study with a zebrafish model

Harden, Jon M. 23 September 2003 (has links)
The aim of this study was to assess sensitivity of early life stage zebrafish to cadmium (Cd). Embryos and larva were exposed to Cd before the formation of skeletal elements. Exposure times were selected to determine whether Cd perturbed developmental processes that lead to skeletal deformities, and to characterize the types of skeletal deformities that occurred. Embryo/larva were exposed to 3μM, 10μM, 30μM, 100μM, 300μM, and 1000μM Cd at 12-36 hours post fertilization (hpf), 36-60hpf, 60-84hpf, and 144-168hpf in one series of experiments. This experiment was conducted at circumneutral pH. A second series of experiments with these same Cd concentrations were also conducted at pH 6 with embryo/larva exposed at 12-36hpf, 36-60hpf, and 60-84hpf. The fish that survived the exposures were raised for 40-60 days whereupon the surviving fish were overdosed with MS222, and X-rayed. The later early life stage fish were more sensitive to Cd toxicity; the chorion appeared to protect the earlier exposed embryos (zebrafish hatch 48-72hpf). Embryo/larva were more resistant to toxicity from dissolved Cd (pH 6) than particulate Cd (circumneutral pH); absence of functional gills during early life stages perhaps explained resistance to dissolved Cd. Notochord lesions (typically lethal within two weeks) occurred when embryos were exposed 12-36hpf. There was no evidence for sensitivity of early life stage zebrafish to Cd induced skeletal deformities that occurred within 40-60 days of Cd exposures. / Graduation date: 2004
263

Molecular and cellular mechanisms of heart regeneration in zebrafish

Sleep Ronquillo, Eduard 30 June 2010 (has links)
In contrast to mammals, zebrafish do have the ability to regenerate their heart after injury. A better understanding of how regenerationcompetent species do so should help developing strategies to enhance human cardiac regeneration. Here, by genetic lineage-tracing using an inducible Cre/lox system, we show that newly formed cardiomyocytes arise from the proliferation of differentiated heart muscle cells. These results argue against a significant contribution of stem or progenitor cells in this process. Our microarray and electron microscopy data provide evidence that cardiomyocyte proliferation is accomplished by limited cardiomyocyte dedifferentiation and increased expression of cell cycle regulators. One of these genes, polo-like kinase 1 (plk1), is upregulated in the regenerating area of the zebrafish heart and, by specifically inhibiting plk1 activity, we show that it is essential for regeneration. We have also identified a series of additional transcripts differentially expressed during zebrafish heart regeneration that warrant further research. The data presented here offer new insights to understanding heart regeneration in zebrafish and should provide useful information for cardiac repair in humans.De manera oposada als mamífers, els peixos zebra sí tenen la capicitat de regenerar el cor després d'una lesió. Entenent millor com s'ho fan les espècies capaces de regenerar hauria d'ajudar-nos a desenvolupar estratègies per a augmentar la capacitat de regeneració en humans. Aquí, mitjançant un sistema Cre/lox de traçat genètic de llinatge, mostrem que la creació de nous cardiomiòcits prové de la proliferació de cèl·lules cardíaques diferenciades. Aquests resultats discrepen amb una contribució significativa de cèl·lules mare o progenitores en aquest procés. Les dades obtingudes de microarray i de microscòpia electrònica evidencien que la proliferació de cardiomiòcits és deguda a una dediferenciació parcial i a un increment de l'expressió de gens que promouen el cicle cel·lular. Un d'aquests, el polo-like kinase 1 (plk1), augmenta d'expressió a l'àrea regenerant del cor de peix zebra i, un cop inhibida la seva activitat, mostrem que és essencial per a la regeneració. També hem identificat una sèrie adicional de trànscrits que s'expressen de manera diferencial durant la regeneració cardíaca en el peix zebra i que mereixen més investigació. Els resultats aquí presents profunditzen en la comprensió de la regeneració cardíaca en el peix zebra i ofereixen informació rellevant per la teràpia cardíaca en humans.
264

The investigation of innate immune system memory in rag1-/- mutant zebrafish

Hohn, Claudia M., January 2008 (has links)
Thesis (Ph.D.)--Mississippi State University. College of Veterinary Medicine. / Title from title screen. Includes bibliographical references.
265

Pax6 and Six1/2 orthologs in leech ectodermal patterning

Quigley, Ian Kirk 09 October 2012 (has links)
Clitellate annelids display conserved mechanisms of segmental ectodermal and mesodermal patterning. These tissues are generated by asymmetric divisions of large stem cells called teloblasts, elongating the ectoderm and mesoderm of the embryo. Each teloblast-derived lineage makes highly stereotyped contributions to the leech: the N, O, P, and Q contribute specific neurons, epidermis, and other ectodermal tissues along the ventral-to-dorsal axis of the embryo, respectively. The N and Q ectodermal lineages appear to be specified autonomously, but specification of the O and P lineages depends upon interactions with other, neighboring teloblast lineages. Until quite recently, there have been precious few teloblast lineage-specific markers, and virtually no molecular candidates for genes influencing the proper differentiation of any of these lineages. Here, I explore the possibility that members of the Pax-Six-Eyes absent-Dachshund network are involved in leech ectodermal patterning. I show that the leech Helobdella sp. Austin has two Pax6 paralogs, and demonstrate that Hau-Pax6A is expressed early in a subset of N-derived cells and O-derived cells. Next, I demonstrate that an ortholog of the six gene family, Hau-six1/2a, is expressed in the P lineage. I show through a series of cell ablations that Hau-six1/2a expression is regulated by neighboring teloblasts in a manner consistent with P fate induction, hinting that this transcription factor may be involved in P specification. The identification of these genes is a first step towards dissecting the molecular mechanisms of ectodermal teloblast differentiation in the leech embryo. The evolutionary context of the deployment of these genes is also discussed. In the appendices, I present two projects on the evolution of pigment patterns in Danio rerio and its relatives. In the first, I show that the larval melanin-containing pigment cells of Danio nigrofasciatus are uniquely redeployed into the adult pigment pattern, in contrast to seven related fishes. In the second, I show that variation in yellow pigment cell populations in different danio species may be dependent on variable signaling through the receptor tyrosine kinase fms pathway. / text
266

Characteristics of the 1990-1994 zooplankton community at a sample location in Lake Michigan near Michigan City, Indiana, with emphasis on zebra mussel (dreissena polymorpha) dynamics

Coffman, Curtis D. January 1995 (has links)
The Summer (May through August) community of crustacean zooplankton and zebra mussel (Dreissena polvmorpha) larvae at a 15 m sample site in Lake Michigan near Michigan City was evaluated for the years 1990 through 1994. Yearly mean densities were compared with investigations done at the same sample location by Johnson (1972) and Ball State University (unpublished data) during 1970 and 1971, respectively to investigate possible changes in community composition during the past 25 years. Potential declines in crustacean zooplankton relating to the 1991 introduction of the filter-feeding zebra mussel were also evaluated.Overall declines in major species since 1970-71 included Bosmina longirostris, Daphnia retrocurva, and Diacyclops thomasi. Recent increases in the nearshore fish population of alewife (Alosa pseudoharengus) and spottail shiner (Notropis hudsonius) may have influenced the densities of these species in recent years. Copepod nauplii were the only crustaceans to increase in overall abundance since the period of 1970-71, as the number of invertebrate predators appeared to decrease. Other species did not show any noticeable change in long-term abundance or during the 1990-94 period.Zebra mussel larvae were first observed in the zooplankton complex studied on June 17, 1991. -Densities of larvae reached maximal levels for the period of study in 1994 with two large reproductive pulses of 195,000 and 210,000/m3 in June and August, respectively. The mean abundance during 1994 made up 65% of the total crustacean zooplankton/zebra mussel community complex. Evaluation of the vertical stratification of zebra mussel larvae in 1994 revealed a strong (r2=0.75, p<0.0005) tendency for veligers to remain in the upper 10 m of the water column due to thermal stratification. / Department of Biology
267

Temperature tolerances and predation susceptibilities of transgenic and wildtype zebra danios, Danio rerio.

Cortemeglia, Cheryl 08 1900 (has links)
Both the upper and lower temperature tolerances of red fluorescent protein transgenic zebra danios and wildtype zebra danios, Danio rerio, were significantly different via two different methods; however, all differences are small (< 1°C) and probably not ecologically important. The U.S. geographic distributions of both transgenic and wildtype zebra danios will not be restricted by their upper thermal tolerances, but will be limited to the southern and western portions of the U.S. by their lower thermal tolerances. Largemouth bass did not preferentially prey upon transgenic zebra danios compared to wildtype danios or wildtypes relative to a native fish. If transgenic or wildtype zebra danios are released into southern or western U.S. waters, it is possible they could be eliminated by predation.
268

Cellular and molecular studies of postembryonic muscle fibre recruitment in zebrafish (Danio rerio L.)

Lee, Hung-Tai January 2010 (has links)
Cellular and molecular mechanisms of postembryonic muscle fibre recruitment were investigated in zebrafish (Danio rerio L.), a standard animal model for developmental and genetic studies. Distinct cellular mechanisms of postembryonic muscle fibre recruitment in fast and slow myotomal muscles were found. In slow muscle, three overlapping waves of stratified hyperplasia (SH) from distinct germinal zones sequentially contributed to a slow and steady increase in fibre number (FN) through the life span. In fast muscle, SH only contributed to an initial increase of FN in early larvae. Strikingly, mosaic hyperplasia (MH) appeared in late larvae and early juveniles and remained active until early adult stages, accounting for >70% of the final fibre number (FFN). The molecular regulation of postembryonic muscle fibre recruitment was then studied by characterising myospryn and cee, two strong candidate genes previously identified from a large scale screen for genes differentially expressed during the transition from hyperplastic to hypertrophic muscle phenotypes. Zebrafish myospryn contained very similar functional domains to its mammalian orthologues, which function to bind to other proteins known to regulate muscle dystrophy. Zebrafish myospryn also shared a highly conserved syntenic genomic neighbourhood with other vertebrate orthologues. As in mammals, zebrafish myospryn were specifically expressed in striated muscles. Zebrafish cee was a single-copy gene, highly conserved among metazoans, ubiquitously expressed across tissues, and did not form part of any wider gene family. Its protein encompassed a single conserved domain (DUF410) of unknown function although knock-down of cee in C. elegans and yeast have suggested a role in regulating growth patterns. Both myospyrn and cee transcripts were up-regulated concomitant with the cessation of postembryonic muscle fibre recruitment in zebrafish, indicating a potential role in regulating muscle growth. Furthermore, a genome-wide screen of genes involved in the regulation of postembryonic muscle fibre recruitment was performed using microarray. 85 genes were found to be consistently and differentially expressed between growth stages where muscle hyperplasia was active or inactive, including genes associated with muscle contraction, metabolism, and immunity. Further bioinformatic annotation indicated these genes comprised a complex transcriptional network with molecular functions, including catalytic activity and protein binding as well as pathways associated with metabolism, tight junctions, and human diseases. Finally, developmental plasticity of postembryonic muscle fibre recruitment to embryonic temperature was characterised. It involved transient effects including the relative timing and contribution of SH and MH, plus the rate and duration of fibre production, as well as a persistent alteration to FFN. Further investigation of FFN of fish over a broader range of embryonic temperature treatments (22, 26, 28, 31, 35°C) indicated that 26°C produced the highest FFN that was approximately 17% greater than at other temperatures. This finding implies the existence of an optimal embryonic temperature range for maximising FFN across a reaction norm. Additionally, a small but significant effect of parental temperature on FFN (up to 6% greater at 24 and 26°C than at 31°C) was evident, suggesting some parental mechanisms can affect muscle fibre recruitment patterns of progeny. This work provides a comprehensive investigation of mechanisms underlying postembryonic muscle fibre recruitment and demonstrates the power of zebrafish as an ideal teleost model for addressing mechanistic and practical aspects of postembryonic muscle recruitment, especially the presence of all major phases of muscle fibre production in larger commercially important teleost species.
269

The involvement of the insulin-like growth factor system during the oocyte maturation and early development of zebrafish. / CUHK electronic theses & dissertations collection

January 2011 (has links)
As a functional unit involved in both maintaining endocrine homeostasis and also producing mature eggs, the ovary plays a central role in female reproduction. The development and function of the ovarian follicles are controlled by gonadotropins released from the pituitary. It is widely accepted that the action of gonadotropins on ovarian follicles is mediated by paracrine/autocrine factors produced by the somatic cells surrounding the oocyte. Increasing evidence indicates that the Igf system is involved in mediating the action of gonadotropins in the ovary. Previously, we identified a gonad-specific Igf subtype (Igf3) distinct from Igf1 and Igf2. This fmding further highlights the importance of the Igf system in the fish ovary. In this thesis, efforts were made to understand the role of the Igf system in ovary using zebrafish as the model organism, and attention was focused on Igf3. / Because the expression of Igf3 is correlated with the LH receptor in zebrafish follicles, the regulation of igf3 by gonadotropins was subsequently studied in the ovary. The expression of igf3 was significantly up-regulated in both ovarian fragments and isolated follicles upon treatment with hCG in dose- and time-dependent manners. Treatment with 8-Br-cAMP or IBMX mimicked the effects of hCG on the expression of igf3 in follicles of different stages. / Four Igfs are present in zebrafish, and our results show that all four igfs are expressed in the ovary of zebrafish and exhibit the differential expression profiles during folliculogenesis. Using a primary culture of zebrafish follicle cells, we demonstrated that hCG stimulated igf2b and igf3 expression but suppressed igf2a expression. Moreover, the effect of gonadotropin could be mimicked by IBMX, which increased the intracellular levels of cAMP, suggesting the possible involvement of cAMP in the gonadotropin-based regulation and differential expression of igf2a, igf2b and igf3. These results also show that the Igf3 is the Igf subtype most sensitive to gonadatropin and cAMP. / In addition, the expression patterns of igf1, igf2a, igf2b, igf3, igf1ra and igf1rb were also studied during zebrafish embryogenesis. The unique temporal and spatial expression patterns of igf1, igf2a, igf2b, igf3, igf1ra and igf1rb were revealed by both real-time PCR and whole mount in situ hybridization, the results suggest divergent functions for these Igfs in early zebrafish development. / Taken together, the present studies provide substantial information about the Igf system, especially that of Igf3 in the zebrafish ovary. Data were gathered regarding Igf3 expression, regulation and functions, which is not only helpful for the understanding of the role of the Igf system in fish reproduction, but also contributes toward uncovering the ovarian signaling network involved in oocyte maturation across vertebrates. This study of igfs gene expression provides direct information to the study of Igf signaling in zebrafish. / To study the function of Igf3, bioactive recombinant Igf3 proteins were prepared using a bacterial expression system. Incubation of follicles with recombinant zebrafish Igf3 significantly enhanced oocyte maturation in time-, dose- and stage-dependent manners. The potential mechanisms of Igf3-induced oocyte maturation were then investigated. Igf3 stimulated oocyte maturation via a steroid-independent manner. Igf3 induced oocyte maturation through Igf1rs and the PI3 kinase, PDE3 and MAP kinase were necessary for Igf3-mediated oocyte maturation in zebrafish. / We first examined the gene expression patterns of Igf3 in the ovary. The igf3 gene in zebrafish was found to be alternatively spliced into two transcripts, with transcript variant 1 exclusively expressed in the gonads and transcript variant 2 only expressed during early development. Using specific antibodies developed for zebrafish Igf3, both the prepropeptide and the mature peptide forms of Igf3 were found to be predominantly expressed in the zebrafish ovary. Real-time PCR and in situ hybridization revealed that igf3 mRNA levels were relatively low in the early follicles but significantly increased after the mid vitellogenic stage (midstage III) and were high in the full grown follicles. In the full grown follicles, igf3 mRNA was detected primarily in the somatic follicular cells, with a low level of expression in the oocytes. Igf3 immunoreactivity was confined to the follicular cells alone. / Li, Jianzhen. / Advisers: Hui Zhao; Hon Ki Christopher Cheng. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 122-150). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
270

Peixes ornamentais do rio xingu: manutenção e reprodução do Acari zebra Hypancistrus zebra Isbrücker & Nijssen, 1991 (Siluriformes, Loricariidae) em cativeiro

RAMOS, Fabrício Menezes 29 April 2016 (has links)
Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-08-31T16:41:40Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_PeixesOrnamentaisRio.PDF: 2336216 bytes, checksum: e8cebf097ea942240722616c1fdcf882 (MD5) / Approved for entry into archive by Irvana Coutinho (irvana@ufpa.br) on 2017-09-04T15:14:31Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_PeixesOrnamentaisRio.PDF: 2336216 bytes, checksum: e8cebf097ea942240722616c1fdcf882 (MD5) / Made available in DSpace on 2017-09-04T15:14:31Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_PeixesOrnamentaisRio.PDF: 2336216 bytes, checksum: e8cebf097ea942240722616c1fdcf882 (MD5) Previous issue date: 2016-04-29 / O Hypancistrus zebra, é espécie ameaçada de extinção, mas que permanece ilegalmente capturada e comercializada, na região do Médio Xingu, devido principalmente à falta de tecnologia de criação que viabilizem sua criação em cativeiros e diminua a exploração de seus estoques naturais. Assim, o principal objetivo deste trabalho é gerar protocolos de manutenção e reprodução do acari zebra, Hypancistrus zebra em cativeiro. Para tanto, foram obtidos 300 exemplares de acari zebra de acordo com a autorização SISBIO nº 38.215-2 e comitê de ética animal nº 03.14.00.017.00.00. O presente trabalho foi dividido em quatro capítulos, sendo o primeiro relacionado a realizar um inventário das espécies do rio Xingu para selecionar a espécie prioritária para o desenvolvimento de tecnologias de cultivo; Avaliar a aceitação de diferentes abrigos e alimentos na manutenção de acari zebra mantido em laboratório; Avaliar diversas condições para a indução da reprodução do acari Zebra, em aquários e; Avaliar o manejo alimentar para os alevinos da geração F1 de Hypancistrus zebra. Com base na matriz foram escolhidos cinco espécies da Família Loricariidae (Hypancistrus zebra, Hypancistrus sp2, Baryancistrus xanthelus, Scobinancistrus sp3 e Ancistrus sp4), uma espécie para Potamotrygonidae (Potamotrygon leopoldii) e duas espécies de Cichlidae (Creniciclha regani e Teleociclha spp.). Com relação à preferência por abrigos em acari zebra o tempo passado nos abrigos foi maior em abrigos de cerâmica (276±51 min dia-1) seguido pelo abrigo de pedra (198±96 min dia-1), fora dos abrigos (134±15 min dia-1), e no abrigo de PVC (70±52 min dia-1). Quanto a preferência por alimentos a ordem de classificação de preferência dos alimentos foi maior para a Artemia sp. seguido pelo alimento peixe, camarão e mexilhão. Porém, quando os peixes alimentados com Artemia sp. ou o mix de alimentos, estes apresentaram maior peso final, comprimento final e ganho de peso em relação aos alimentos isolados com o camarão e peixe. Com relação à frequência e taxa de alimentação, não houve interação entre a taxa e a frequência de alimentação sendo que as frequências de 2 e 3 alimentações diárias e a taxa de alimentação de 10% peso vivo dia-1 promovem melhores resultados de desempenho zootécnico. Também foi observado que a melhor densidade de estocagem é de 2,00g L-1 por proporcionar as melhores taxas de crescimento específico. Em relação a reprodução foram observadas cinco desovas de diferentes casais, sendo 3 para 1 macho e 2 fêmeas. O macho maior é o dominante, territorialista e apresenta cuidado parental. Postura média de 13,8±6,72 ovos, diâmetro de 4,4±0,12, volume de 41,4 mm3 e volume de vitelo 34.3 mm3. A eclosão ocorre com 7 dias pós fertilização (PF) e no 17 dias PF o saco vitelinico foi absorvido. Os diferentes valores testados de condutividade elétrica na água e tratamentos hormônais não foram suficiente para promover desovas no acari zebras. Os valores de desempenho em alevinos de acari zebra permaneceram semelhantes entre os tratamentos testados. Conclui-se assim, que o acari zebra é a espécie do rio Xingu prioritária no desenvolvimento de tecnologia. O uso de refúgios de cerâmica é o mais indicado, em Hypancistrus zebra. Os acaris zebras devem ser cultivados na densidade de 2g L-1, sendo que sua alimentação não é aleatória, tendo preferência por artêmia, que devem ser distribuídas em 10% peso vivo dia-1 em 2 alimentações diárias. Adicionalmente alimentos complementares à artêmia podem ser conjugadas para proporcionar desempenho similar. A reprodução em cativeiro é possível porém novas técnicas que propiciem o escalonamento da reprodução devem ser avaliadas. Além disso, devido a longa fase larval e com grande reserva de saco vitelínico, promove alevinos mais saudáveis e resistentes sendo que a frequência alimentar não influência diretamente no desempenho. / The Hypancistrus zebra is an endangered species, but remains illegally captured and sold in the Middle Xingu region, mainly due to lack of creating technology that enable its creation in captivity and reduce the exploitation of natural stocks. Thus, the main objective of this work is to generate maintenance protocols and reproduction of zebra pleco, Hypancistrus zebra in captivity. Therefore, we obtained 300 copies of acari zebra according to SISBIO authorization No. 38215-2 and ethics committee animal No 03.14.00.017.00.00. This study was divided into four chapters, the first being related to conduct an inventory of the species of the Xingu River to select the priority species for the development of farming technologies; Evaluate the acceptability of different food and shelter in maintaining zebra pleco maintained in the laboratory; To evaluate various conditions for inducing playback zebra pleco in tanks and; Evaluate feeding management for fry of F1 generation Hypancistrus zebra. Based on the array were chosen five species of the family Loricariidae (Hypancistrus zebra, Hypancistrus sp.2, Baryancistrus xanthelus, Scobinancistrus sp.3 and Ancistrus sp.4), one species to Potamotrygonidae (Potamotrygon leopoldii) and two species of cichlid (Creniciclha regani and Teleociclha spp.). With respect to the preference for shelters acari zebra time spent in shelters was higher in clay shelters (276 ± 51 day min-1) followed by the stone shelter (198 ± 96 day min-1), outside the shelter (134 ± 15 day min-1), and PVC under (70 ± 52 day min-1). The preference for food the sort order of preference of the food was higher for Artemia sp. followed by food fish, shrimp and mussels. But when the fish fed with Artemia sp. or mix food, they had higher final weight, final length and weight gain compared to single foods with shrimp and fish. Regarding the frequency and feed rate, there was no interaction between the rate and the supply frequency and the frequency 2:03 daily feeds and feed rate of 10% day-1 body weight promote better results of production performance. It was also observed that the best storage density is 2.00 g L-1 to provide the best specific growth rate. Regarding reproduction were observed five spawns from different couples, and 3 to 1 male and 2 females. The biggest male is the dominant territorialist and have parental care. average position of 13.8 ± 6.72 eggs, diameter of 4.4 ± 0.12, volume 41.4 mm3 volume and calf 34.3 mm3. The outbreak is 7 days post fertilization (PF) and PF 17 days the yolk sac has been absorbed. The different values tested for electrical conductivity in the water and hormonal treatments were not enough to promote spawns in acari zebras. Performance figures in fingerlings acari zebra remained similar between the treatments. It follows therefore, that the zebra pleco is the kind of priority Xingu river in technology development. The use of ceramic refuges is the most suitable in Hypancistrus zebra. The zebra pleco should be cultivated at a density of 2 g L-1, and its power is not random, with preference for brine shrimp, which must be distributed in 10% day-1 body weight in 2 daily feedings. In addition to complementary food brine shrimp can be combined to provide similar performance. Captive breeding is however possible new techniques that facilitate the scheduling of reproduction should be evaluated. Furthermore, due to the short larval stage and with great reserve yolk sac, promote healthier fry and being resistant to feed frequency not directly influence on performance.

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