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Desempenho reprodutivo e diferenciação gonadal em piau-três-pintas, Leporinus friderici, Bloch 1794 /Souza, Thiago Gonçalves de. January 2015 (has links)
Orientador: Sérgio Ricardo Batlouni / Banca: Rafael Henrique Nóbrega / Banca: George Shigueki Yasui / Banca: Maria Inês Borella / Banca: Diogo Teruo Hashimoto / Resumo: Os objetivos deste trabalho foram avaliar o desempenho reprodutivo e o processo de diferenciação gonadal do Leporinus friderici. Primeiramente avaliamos a evolução do processo meiótico e o desempenho reprodutivo de matrizes de L. friderici induzidas com doses convencionais e reduzidas de extrato bruto de hipófise de carpa (EC) e de hormônio liberador de gonadotropinas análogo ao de mamífero associado à metoclopramida (mGnRHa + MET). Posteriormente, investigamos o início e as características do processo de diferenciação gonadal desta espécie expostos a 25 e 29°C. Para a avaliação do desempenho reprodutivo, utilizamos o EC em doses de 0,5 e 5,5mg/Kg (doses convencionais) e em doses de 0,5 e 1,0mg/Kg (doses reduzidas). Paralelamente utilizamos dose única de 40pg de mGnRHa + 20mg de MET/Kg (dose convencional) e duas doses de 4pg + 2mg; e 8pg + 4mg, de mGnRHa + MET/Kg (doses reduzidas). Para avaliação do processo de diferenciação gonadal foram amostrados aleatoriamente cinco peixes com 50, 70, 90, 110, 130, 150, 170, 190, 210 e 240 dias após eclosão (DAE), expostos a 25 e 29°C, em sistema de recirculação de água. Concluimos que embriões viáveis de L. friderici podem ser obtidos com doses reduzidas de EC, mas não com doses convencionais. Não foi possível obter embriões viáveis de L. friderici com uso de mGnRHa + MET, pelo menos com as doses e procedimentos aqui empregados, pois estes causaram baixa fertilidade, baixa eclosão e redução da qualidade dos ovos. Com relação ao processo de diferenciação gonadal, demonstramos que a temperatura mais elevada (29°C) provocou aumento no comprimento padrão (CP) e peso médio (P), intensificou a diferenciação gonadal e propiciou um maior número de fêmeas de L. friderici. Concluindo, é possível que a espécie apresente alguma toxicidade provocada pelo excesso de GnRH, hormônio luteinizante ou aos esteroides gonadais, os quais seriam transmitidos da fêmea para... / Abstract: The objectives of this study were to evaluate the reproductive performance and gonadal differentiation process Leporinus friderici. First we assess the evolution of the meiotic process and the reproductive performance of L. friderici broodstock induced with conventional and lower dose of crude carp pituitary extract (EC) and mammalian gonadotropin releasing hormone analogue associated with metoclopramide (mGnRHa + MET ). Subsequently, we investigated the beginning and the characteristics of gonadal differentiation process of this species exposed at 25 and 29°C. For the evaluation of reproductive performance, we used the EC at doses of 0.5 and 5.5 mg / kg (conventional dose) and at doses of 0.5 and 1.0mg / kg (lower doses). Parallel use of a single dose of 40pg + 20mg mGnRHa MET / kg (conventional dose) and two doses of 4pg + 2mg; and 4pg + 8mg of mGnRHa + MET / kg (lower doses). For evaluation of gonadal differentiation process were randomly sampled five fish 50, 70, 90, 110, 130, 150, 170, 190, 210 and 240 days after hatching (DAE), exposed to 25 and 29°C in recirculation system water. We conclude that viable L. friderici embryos can be obtained with low doses of EC, but not with standard doses. Could not get viable embryos L. friderici with use of mGnRHa + MET, at least with the doses and procedures used here, as these caused low fertility, low hatching and reduced egg quality. With respect to gonadal differentiation process, we have demonstrated that the higher temperature (29°C) caused an increase in average weight (P) and standard length (CP), intensified gonadal differentiation and provided a greater number of females L. friderici. In conclusion, it is possible that the species has any toxicity caused by excess GnRH, luteinizing hormone or the gonadal steroids, which would be transmitted to the female embryos before the ovulation process, killing them. With the production of females, which is the genre of greater economic ... / Doutor
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Fontes lipídicas e ácidos graxos essenciais no desenvolvimento ovariano e desempenho reprodutivo de jundiás Rhamdia quelen /Hilbig, Cleonice Cristina. January 2015 (has links)
Orientador: Laura Satiko Okada Nakaghi / Coorientador: Robie Allan Bombardelli / Banca: Luiz Edvaldo Pezzato / Banca: Renata Guimarães Moreira Whitton / Banca: George Yasui / Banca: José Augusto Senhorini / Resumo: A nutrição de reprodutores é um dos principais aspectos relacionados com a qualidade dos ovos e larvas produzidos. Os lípidos e sua composição em ácidos graxos são considerados importantes para o desenvolvimento das gônadas, sobre hormônios gonadotrópicos e esteroidiais, bem como influencia a formação de estruturas biológicas incluindo membranas celulares. Os ácidos graxos essenciais para os peixes são o ácido linoleico e o ácido linolênico, que quando convertidos fornecem os ácidos graxos poli-insaturados, como ARA, EPA e DHA, respectivamente. O óleo de pescado marinho é considerado uma fonte ideal de ácidos graxos poli-insaturados, no entanto, os óleos vegetais são mais comumente utilizados em dietas de peixe. Assim, o objetivo deste estudo foi avaliar o desenvolvimento ovariano e o desempenho reprodutivo de jundiás (Rhamdia quelen) alimentados com diferentes fontes lipídicas (óleo de soja, óleo de peixe marinho, óleo de palma refinado e a mistura dos três óleos). As fontes lipídicas não influenciaram no desenvolvimento do ovário, nos níveis de estradiol e 17α-hidroxyprogesterona, e nos índices gonadossomáticos. No entanto, o ácido graxos influenciaram no perfil de ácidos encontrados no fígado, gônadas e oócitos. Adicionalmente dietas 'a base de o óleo de palma resultou em melhores taxas de fertilização, sendo recomendado sua utilização em substituição ao óleo de pescado marinho / Abstract: Broodstock nutrition is one of the main aspects related with the quality of eggs and larvae produced. Lipids and its fatty acid composition are considered important on gonadal development, gonadotropic and steroid hormones, as well as influencing the formation of biological structures including cell membranes. In fish linoleic and linolenic are the essential fatty acids, which mabe converted into polyunsaturated fatty acids, like ARA, EPA and DHA, respectively. The marine fish oil are good sources of polyunsaturated fatty acids, however, vegetable oils are more communly used in fish diets. Thus, the aim of this study was to evaluate the ovarian and reproductive development of silver catfish (Rhamdia quelen) fed with lipid sources (soybean oil, marine fish oil, refined palm oil and a mixture). The lipid sources did not influence ovarian development, levels of estradiol, 17α-hidroxyprogesterona, and gonadosomatic index. However, the fatty acid changed fatty acid profile found in the liver, gonads and oocytes. Additionally, palm oil give rise to better fertilization rates and are recommended, suggesting that it may be used for fish oil replacement / Doutor
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Metodologias de avaliação de sêmen e procedimentos de fertilização artificial de surubim-do-paraíba, Steindachneridion parahybae /Sanches, Eduardo Antônio. January 2012 (has links)
Orientador: Elizabeth Romagosa / Banca: Laura Helena Orfão / Banca: Luis David Solis Murgas / Banca: Marcos Weingartner / Banca: Adilson Reidel / Resumo: O objetivo do trabalho foi de adaptar metodologias de análises espermáticas e aprimorar o processo de fertilização artificial e condições de estocagem de gametas de surubim-do-paraiba, Steindachneridion parahybae: espécie de peixe criticamente ameaçada de extinção. Para tanto, foram realizados quatro ensaios experimentais: (1) validação de método e avaliação dos parâmetros espermáticos por meio de software livre. (2) determinação da dose inseminante e volume de água empregados na fertilização artificial; (3) estocagem de ovócitos in natura em quatro temperaturas ao longo de 355 minutos; (4) estocagem do sêmen in natura em quatro temperaturas ao longo 112h. Observou-se que o método de análise espermática utilizando o software de código aberto ImageJ/plugin CASA é uma ferramenta eficiente, exata, objetiva e barata, além de possibilitar uma nova perspectiva de análises em peixes nativos. As configurações estabelecidas no presente trabalho poderão servir de base para novos trabalhos relacionados às análises espermáticas do surubim-do-paraíba, bem como de outras espécies. Verificou-se que a quantidade de espermatozóides e o volume de água interferem diretamente no procedimento de fertilização artificial, com melhores resultados na utilização de 5,5×106 espermatozóides ovócito-1 e 1,0mL de água g-1 de ovócitos. Foi observado que a estocagem de ovócitos e sêmen de forma in natura não é recomendada em ambientes com temperaturas superiores a 25ºC e inferiores a 15ºC. Temperaturas intermediárias (15-25ºC) possibilitam melhores condições e prolongam a qualidade dos gametas, entretanto, recomenda-se em procedimentos de fertilização artificial da espécie, a coleta do sêmen antes que os ovócitos. Os resultados obtidos no presente trabalho além de proporcionarem aumento das... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim was to adapt methodologies of sperm analysis and to improve the artificial fertilization process and gamete storage conditions of surubim-of-paraiba, Steindachneridion parahybae: critically endangered fish species. So that, four experimental tests were performed: (1) validation of method and evaluation of sperm parameters using free software. (2) determination of the inseminating dose and water volume used in artificial fertilization, (3) storage of fresh oocytes into four temperatures over 355 minutes, (4) storage of fresh semen into four temperatures over 112h. It was observed that the sperm analysis method using open source software ImageJ/plugin CASA is an effective tool, accurate, objective and inexpensive, besides enables a new perspective of the analysis on the native fish. The settings established in this study could serve as a basis for further work related at sperm analysis of surubim-do-paraiba and other species. It was found that sperm quantity and water volume interfere directly in the procedure of artificial fertilization, with improved results on usage of 5.5×106 spermatozoa oocyte-1 and 1.0 ml of water g-1 of oocyte. It was observed that the fresh oocytes and sperm storage is not recommended in environments with temperatures above 25ºC and below 15ºC. Intermediate temperatures (15-25ºC) enable better results and prolong the gametes quality, however, it is recommended in the artificial fertilization procedures the semen collection before the oocytes. The results obtained in this study providing increased rates of fertilization and hatching, besides to allow gametes optimization through of the utilization of controlled manner, and with satisfactory quality for more time after collection. Besides, these results provide a basis for future research, contributing to the... (Complete abstract click electronic access below) / Doutor
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Efeito da estocagem a curto prazo e da temperatura sobre gametas de jundiá, Rhamdia quelen (Quoy & Gaimard, 1824) /Sanches, Eduardo Antônio. January 2009 (has links)
Orientadora: Elizabeth Romagosa / Banca: Sérgio Ricardo Batlouni / Banca: Rodolfo Nardez Sirol / Resumo: O trabalho foi conduzido com o objetivo de avaliar o efeito da temperatura de estocagem a curto prazo e da temperatura da água sobre os ovócitos e sêmen de jundiá, Rhamdia quelen. O experimento foi realizado em três etapas: (1) avaliar a qualidade dos ovócitos após estocagem e ativação em diferentes temperaturas; (2) padronizar a utilização de análise espermática computadorizada por meio de softwares livres; (3) avaliar os parâmetros espermáticos computadorizados após estocagem e ativação em diferentes temperaturas. Para a primeira, utilizou-se um delineamento experimental fatorial no tempo (5×3×3×3), com os tratamentos realizados em triplicata a cada 48h, na exposição de ovócitos nas temperaturas de 15; 25 e 35ºC e, ativados com água à 15; 25 e 35ºC cada, nos períodos de: 0; 45; 90; 135 e 180 minutos pós-coleta. A segunda etapa foi realizada através da captura de vídeos da movimentação espermática pelo software AMCAP, a uma taxa de 60 frames por segundo, processados no software VIRTUALDUB e analisados no software IMAGEJ por meio do aplicativo CASA. Os seguintes parâmetros foram analisados: taxa de motilidade espermática (MOT), velocidade curvilinear (VCL), velocidade média do deslocamento (VMD), velocidade em linha reta (VLR), linearidade (LIN), balanço (BAL) e freqüência de batimentos (FBAT). Os parâmetros espermáticos foram avaliados em um segundo de imagem nos tempos de 15, 25 e 35 segundos após a ativação espermática. Para a terceira etapa foi utilizado um delineamento experimental fatorial no tempo semelhante à primeira ,com 13 tempos de avaliação pós-coleta: 0; 2; 4; 6; 8; 10; 12; 16; 20; 24; 32; 40 e 48 horas. Os tratamentos foram realizados em triplicata e em protocolos sequenciais a cada 50 horas avaliando-se os parâmetros obtidos na segunda etapa. Estes foram submetidos às análises de correlação (Pearson) ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study was conducted to evaluate the effect of temperature of storage in the short-term and the temperature of the water on the oocytes and sperm of jundiá, Rhamdia quelen. The experiment was conducted in three stages: (1) assess the quality of oocytes after storage and activation at different temperatures; (2) standardize the use of computerized sperm analysis by software free, (3) evaluate the computerized sperm parameters after storage and activation at different temperatures. For the first, was used a factorial experimental design in time (5×3×3×3), with treatments performed in triplicate every 48 hours, the exposure of oocytes at temperatures of 15, 25 and 35 C, and activated with water to 15, 25 and 35 C each, in the periods of: 0; 45; 90; 135 and 180 minutes post-collection. The second stage was performed by video capture of the movement of sperm through AMCAP software at a rate of 60 frames per second, processed and analyzed in VirtualDub software and ImageJ software using the CASA application. The following parameters were analyzed: rate of sperm motility (MOT), velocity curvilinear (VCL), velocity average path (VAP), velocity straight line (VSL), linearity (LIN), wobble (WOB), beating cross frequency (BCF). The sperm parameters were evaluated in a second image in the times of 15, 25 and 35 seconds after sperm activation. For the third step we used a factorial experimental design similar to the first in time, with 13 times of evaluation post-collection: 0; 2; 4; 6; 8; 10; 12; 16; 20; 24; 32; 40 and 48 hours. The treatments were performed in triplicate and sequencing protocols to be evaluated every 50 hours if the parameters obtained in the second stage. These were submitted to analysis of correlation (Pearson). The significant parameters (P<0.05) were summarized by the principals components analysis. For the first stage interaction (P<0.05) between time and temperature... (Complete abstract click electronic access below) / Mestre
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Reproductive behaviour of the skunk clownfish, Amphiprion akallopisos, under captive conditionsHaschick, Rory Dean January 1998 (has links)
The objectives of the study were to determine whether or not behaviour could be used to predict spawning in Amphiprion akallopisos, and to document the behaviour of this species under various environmental conditions in captivity. The spawning behaviour of A. akallopisos was studied and quantified. Three behaviour patterns - belly touching, nest cleaning by the female and mutual nest cleaning (by the male and the female) were identified as predictors for spawning. The reproductive behaviour of A.akallopisos under three photoperiods was investigated. The photoperiods were: 14L:10D, 10hr15minL:13hr45minD and a natural photoperiod cycle condensed into three months. A. akallopisos maintained under 14 L:10D exhibited a significantly higher frequency and duration of chasing, nest cleaning and total interaction compared to fish kept under 10hr15minL:13hr45minD. A photoperiod of 14L:10D was selected for further studies. As manipulation of photoperiod did not induce spawning, GnRHa was administered to the fish in the diet at levels of 10, 20, 40 and 80 μg/kg BW. Control groups were fed untreated food. None of the dosages were successful in inducing spawning, or spawning behaviour in A. akallopisos. It is possible that the method of hormone application was not suitable for this species. It is also possible that behaviour may regulate blood hormone levels as opposed to endocrine status influencing behaviour. In the third trial, A. akallopisos was maintained with, and without sea anemones in order to determine whether or not anemone hosts are necessary for spawning. The presence of anemones did not induce spawning and A. akallopisos kept without anemones exhibited significantly more interactive behaviour than fish kept with hosts. Spawning of A. akallopisos at a later date without anemones suggests that anemones are not necessary for spawning in A. akallopisos. Light intensity was investigated as a cue for spawning. The reproductive behaviour of A. akallopisos was then studied under light intensities of 4.16 x 10¹⁵ quanta.sec⁻¹.cm⁻², 8.85 x 10¹⁵ quanta.sec⁻¹.cm⁻² and this intensity plus natural light. Spawning occurred mainly under 8.85 x 10¹⁵ quanta.sec⁻¹.cm⁻². Fish maintained under this light intensity exhibited significantly more of nest cleaning behaviour in terms of frequency and duration than fish maintained under low light intensity. A minimum light intensity of 8.85 x 10¹⁵ quanta. sec⁻¹.cm⁻² is recommended for conditioning of this species. This study can be of practical relevance to hatchery managers who can use the methods developed and record predictors for spawning in A. akallopisos and other Amphiprion species. In this way imminence of spawning may be estimated. Most importantly, the study also has academic merit as little work has been undertaken in this field. Although the observational method used in this study was adequate for the purposes of the investigation, future work of this nature should incorporate other methods of documenting gonadal development such as gonadal staging and GSI in order to obtain more conclusive results.
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Reproductive isolation between two co-existing populations of stickleback (Gasterosteus) in Enos Lake, Vancouver IslandRidgway, Mark S. January 1982 (has links)
Morphological, biochemical, and trophic evidence from other studies indicate that two populations of stickleback (Gasterosteus) co-exist in Enos Lake, Vancouver Island. One population is limnetic and the other is benthic (the names allude to their foraging behaviour and use of space). In this study, field observations, mate selection experiments, and courtship behaviour experiments were conducted to determine if the two stickleback populations are reproductively isolated.
When breeding, limnetic males develop red throats whereas benthic males become uniformly black. In the field limnetic and benthic males nest in different habitats. Despite this difference, reproductive males and females of each population encountered each other, but in the few cases where courtship occurred, it never went beyond the initial stages of the lead-follow sequence. Apparently behavioural differences in courtship contributed to the break off of these natural courtships. In mate selection experiments, males and females of each population preferred mates from their own population. In the courtship experiments, behavioural differences between limnetics and benthics were found to be greatest in the early stages of courtship. With females from their own population, benthic males were more aggressive in their approach and leading sequences than limnetic males. In the beginning of the lead-follow phase, benthic females tend to position themselves above benthic males whereas limnetic females tend to position themselves alongside limnetic males. Male courtship behaviour was sometimes dependent on the phenotype of the female courted; benthic males bit and chased limnetic females whereas, limnetic males bit and led benthic females in a meandering path to the nest. Since the mate choice experiments indicated total positive assortative mating between limnetics and benthics, it is likely that the behavioural differences found in courtship behaviour contribute to reproductive isolation between the limnetic and benthic sticklebacks in Enos Lake. / Science, Faculty of / Zoology, Department of / Graduate
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Experimental studies on the behavioral component of reproductive cost in Daphnia pulexKoufopanou, Vasso. January 1983 (has links)
No description available.
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Aspects of Fathead Minnow Reproductive BehaviorPyron, Mark 05 1900 (has links)
Following a study of normal reproductive behavior of fathead minnows, Pimephales promelas, experiments were conducted to determine the stability/variability of behavior by sexually mature, territorial males under a variety of manipulated conditions. Collectively, these experiments indicate that although the individual behaviors of fathead minnows appear to be quite variable, the overall process, reproductive behavior, is stable.
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Larval development and reproductive strategies of Central Amazon fishesAraujo Lima, Carlos A. R. M. January 1990 (has links)
Larval development and reproduction of 19 species of Central Amazonian fish (five cichlids, two siluriforms, one osteoglossiform and 11 characiforms) were studied over two years. Most species spawn during the flooding season. The cichlids, the siluriforms and two species of characiform are nest spawners, reproducing in the littoral areas of the floodplain. The osteoglossiform is a mouth-brooder. The remaining characiforms spawn in the river channels and show no parental care. Two main strategies explain 90% of the variability of reproductive traits found among the 19 species. The first strategy is used by riverine spawners (characiforms). They have high fecundity , high to very high reproductive expenditure (calories per spawn per wet weight of female) and spawn once a year during a short season. Their eggs vary in size from 0.06 to 0.3 mg and have intermediate to high calorific value. The second strategy is used by the cichlids and two species of characiforms. They have low fecundity, low reproductive expenditure, long spawning season, multiple spawnings per season and some of them show parental care. Their eggs vary in size from 0.4 to 1.2 mg and have an intermediate calorific content. The other three species show distinct combinations of reproductive traits, but have as common feature a high reproductive expenditure, a short annual spawning season and parental care. Patterns of larval development are correlated with egg size and adult spawning sites. Egg size explained most of variability of larval body size at hatching, pectoral fin bud, eye pigmentation, jaw formation, swim bladder inflation, onset of swimming, first feeding and maximum size attained with exclusively endogenous feeding. The pattern of blood circulation of the larvae was correlated with the spawning sites. Larvae of riverine spawners are small, utilize yolk efficiently and are relatively resistant to starvation. Newly hatched larvae of riverine spawners seem to be very sensitive to physico-chemical conditions of the floodplain lakes, but by the first feeding stage they develop some resistance to the low availability of oxygen. Larvae of littoral spawners are large, utilize yolk less efficiently, and seem to be resistant to low concentrations of oxygen. The resistance of larvae to oxygen deficiency is correlated with the development of the larval respiratory system. It is suggested that egg size of riverine spawners was selected to optimize the distance of the dispersal of the larvae in a range of floodplain lakes. Conversely, egg size of floodplain spawners seemed to be selected to optimize larval survival in the spawning lake. The results are further discussed in relation to life history models.
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Reprodução induzida e desenvolvimento inicial do Jundiá Leiarius marmoratus (PISCES: SILURIDAE) /Mira López, Tatiana María. January 2014 (has links)
Orientador: Fausto Foresti / Banca: Diogo Teruo Hashimoto / Banca: José Sávio Colares de Melo / Banca: Alexandre de Azevedo / Banca: Pablo Emilio Cruz Casallas / Resumo: O Jundiá Leiarius marmoratus é um peixe siluriforme da família Pimelodidae, com migração reprodutiva durante a época de chuvas e que ocorre nas bacias dos rios Amazonas e Orinoco. É uma espécie de grande valor econômico por suas características zootécnicas favoráveis, como pouco canibalismo na fase de larvicultura e boa aceitação de alimentos secos na fase adulta. Pode ser uma espécie vulnerável às alterações de hábitat em função do comportamento essencialmente reofílico em pelo menos uma fase do seu ciclo de vida. Neste contexto, estudos que possibilitem a reprodução adequada em cativeiro e o conhecimento da biologia do desenvolvimento inicial da espécie são extremamente necessários, visando produzir juvenis para a aquicultura ou para subsidiar os programas de conservação das suas populações. O presente estudo tem como objetivo estabelecer um protocolo de reprodução em cativeiro com duas substâncias hormonais, extrato bruto de hipófise de carpa (EHC) e Ovopel® (OVO: mGnRHa + metoclopramida), e descrever o desenvolvimento de embriões e o crescimento das larvas do L. marmoratus. Para o estabelecimento dos protocolos de indução à reprodução, machos e fêmeas adultos foram selecionados com base na observação de características externas indicadoras de maturidade reprodutiva, como ventre abaulado nas fêmeas e liberação de sêmen nos machos. Os machos foram injetados com OVO na dosagem total de 2,5 mg.kg-1. Nas fêmeas foram testadas duas substâncias indutoras: um grupo foi injetado com EHC na dosagem total de 5,5 mg.kg-1 e um segundo grupo foi injetado com OVO na dosagem total de 5,5 mg.kg-1. As fêmeas responderam eliminando ovócitos com 175,9 e 177,2 horas-grau para EHC e OVO, respectivamente, a uma temperatura média da água de 25,5 ± 8,8 °C (p>0.05). O diâmetro dos ovócitos ovulados foi de 665 ± 3,11 μm. Parâmetros reprodutivos tais como fecundidade total e relativa e fertilidade foram ... / Abstract: The Jundiá (Leiarius marmoratus) is a siluriform fish of the family Pimelodidae with reproductive migration during the rainy season, which occur in the basins of the Amazon and Orinoco rivers. It is a species of great economic value for its favorable husbandry characteristics, as little cannibalism in hatchery phase and good acceptance of dry foods in adulthood. It may be a vulnerable species due to changes in habitat because its reofilic behavior in at least one stage of its life cycle. In this context, studies that provide an appropriate captive breeding and knowledge of the biology of early development of the species, are sorely needed, aiming to produce juveniles for aquaculture or to support conservation programs their populations. The present study aims to establish a protocol for captive breeding with two hormonal substances, crude carp pituitary extract (EHC) and Ovopel ® (OVO: mGnRHa + metoclopramide), and describe the development of embryos and growth of larvae L. marmoratus. To establish the induction and reproduction protocols, males and females were selected based on observing external characteristics indicative of reproductive maturity, as bulging belly in females and emission of semen in males. Males were injected with OVO in total dosage of 2.5 mg.kg-1. In females, two inducing substances were tested: one group was injected in total dosage of 5.5 mg.kg-1 EHC and a second group was injected in total dosage of 5.5 mg.kg-1 of OVO. Females responded with oocytes elimination with 175.9 and 177.2 hours-degree for EHC and OVO at an average water temperature of 25.5 ± 8.8 ° C (p> 0,05). The diameter of ovulated oocytes was 665 ± 3.11 μm. Reproductive parameters such as the total and relative fecundity, and fertility were the same for both inducing substances (p> 0.05), with values of 612,000 and 605,400 oocytes.female-1 (fecundity), 125,800 and 132,000 oocytes.kg-1 body weight of the female (fecundity on weight) and 74.7 ... / Doutor
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