Consulta: subjectFacets:"Reproductive cycle"
Registros recuperados: 45
Data/hora: 06/06/2024 02:29:44

Аспекты биологии размножения Scapharca inaequivalvis (Bruguière) (Bivalvia, Arcidae) в Черном море
Provedor de dados: 13
Autores: Чикина, М. В.; Коючкина, Г. А.; Кучерук, Н. В.
Приведены результаты изучения репродуктивного цикла, темпов роста, возраста наступления половой зрелости и плодовитости вселившегося в Черное море моллюска Scapharca inaequivalvis (Bruguière, 1789).
Tipo: Journal Contribution
Palavras-chave: Reproductive cycle.
Ano: 2003
URL: http://repository.ibss.org.ua/dspace/handle/99011/584

Aspectos da biologia reprodutiva de Bothrops jararaca em cativeiro (Serpentes, Viperidae)
Provedor de dados: 76
Autores: Alves,Maria Lúcia Machado; Leitão-de-Araujo,Moema; Witt,André Alberto.
The reproduction of Bothrops jararaca (Wied, 1824) in captivity in ordened to determine the intercourse period, births, number of neonates, proportion of males and females per litter were performed between 1989 and 1999. Fifty eight females were observed, 16 intercourses in captivity, 45 females arrived already fertilized from nature and 53 litters, resulting on the birth of 426 live neonates, 67 infertile egg masses, 18 stillborn neonates and 4 abnormal neonates. The intercourse period was from february to december and the births happened between february and may. From the two gestacional periods observed, the shortest one was 152 days and the longest 239. The average amount of live neonates per litter was 8,04. Among 323 neonates, 47,68% were males and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bothrops jararaca; Reproductive cycle; Neonates; Development; Captivity.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212000000200009

Descrição do ciclo reprodutivo de Donax hanleyanus (Bivalvia, Donacidae) no sul do Brasil
Provedor de dados: 76
Autores: Gil,Guacira M.; Thomé,José W.
The changes in gonadal development in male and female of Donax hanleyanus Philippi, 1847 are described. Gonad development and spawning seasons were assessed by monthly sampling of population from Arroio Teixeira beach, southern Brazil. Histological examination of clams showed in the most of the adult population sampled that the spawning is practically continuous, without any period of sexual rest. There are two main periods of gametogenesis, in winter and in summer, being the degree of maturation longer in the latter. The water temperature is stimulant on gametes proliferation and spawning.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Donax; Reproductive cycle; Spawning season.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212004000300008

Peculiarities of reproduction and generative production of tropical copepods
Provedor de dados: 5
Autores: Sazhina, L.
The aim of the present investigation consisted in revealing the regular natural changes of fecundity in mass pelagic copepods of the World Ocean tropical zone. Particular emphasis was placed on determination of the clutch size, duration of development, rate of generative production formation at both organism and population levels, and connection of these processes with environmental conditions. The major difficulty lay in the fact that most mass species of tropical copepods are laying eggs immediately into water thus complicating the determination of quantitative characteristics of reproduction.
Tipo: Text
Palavras-chave: Copepoda; Pelagic environment; Clutch; Environmental factors; Population density; Tropical environment; Fecundity; Biological production; Reproductive cycle.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-1525.pdf

Etude cytologique de la gamétogenèse, de la sex-ratio et du cycle de reproduction chez l'huître perlière Pinctada margaritifera (L) var. cumingii (Jameson), (mollusques, bivalves). Comparaison avec le cycle de Pinctada maculata (Gould)
Provedor de dados: 5
Autores: Thielley, Maryse.
The population of Pinctada margaritifera and Pinctada maculata lay eggs throughout the year. Temperature variations induce huge but asynchronous laying. Preferential periods of gonad maturity correspond to the season changings in both species. However. some differences between the two specics are noticed. Both species are protandric hermaphrodites. Female condition is unstable: a reversion to the male condition may be observed and is probably linked with stress. The average size for the first sexual maturation as weil as for sexual conversion are specified in P. margaritifera. The breeding conditions induce modifications in some reproductive cycle processes (maturation, sex-ratio). Some conditions suitable for reproduction may become unfavorable to...
Tipo: Text
Palavras-chave: Gamétogenèse; Cycle de reproduction; Sex-ratio; Pinctad margaritifera; Mollusque; Bivalve; Huître perlière; Gametogenesis; Reproductive cycle; Sex-ratio; Pinctada margaritifera; Mollusca; Bivalvia; Pearl oyster.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00440/55208/56677.pdf

Gametogenic cycle and reproductive effort of the tropical blacklip pearl oyster, Pinctada margaritifera (Bivalvia : Pteriidae), cultivated in Takapoto atoll (French Polynesia)
Provedor de dados: 5
Autores: Pouvreau, Stephane; Gangnery, Aline; Tiapari, Jerome; Lagarde, Franck; Garnier, Matthieu; Bodoy, Alain.
The gametogenic cycle and the reproductive effort of the blacklip pearl oyster, Pinctada margaritifera, cultivated in Takapoto lagoon were studied for a 1-year period (March 1997-April 1998) by bimonthly observations of gonadal sections, dry tissue weights and gonadal index in a population of pearl oyster composed of three age-groups. pearl oysters attained sexual maturity in the end of their first year (height approximate to 40 mm), implying that P. margaritifera is a late-maturing species in comparison with other Pteriidae. This species was also confirmed to be a marked protandrous successive hermaphrodite in culture, with 100 % of males at first maturity and 75 % in older pearl oyster (height &gt; 120 mm). The general pattern of gametogenic activity,...
Tipo: Text
Palavras-chave: French Polynesia; Reproductive effort; Reproductive cycle; Tropical aquaculture; Gametogenesis; Blacklip pearl oyster; Polynésie française; Effort de reproduction; Cycle de reproduction; Aquaculture tropicale; Gamétogenèse; Huître perlière.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-1391.pdf

Cycles saisonniers, reproduction et qualite des ovocytes chez Pecten maximus en rade de Brest
Provedor de dados: 5
Autores: Paulet, Yves-marie; Bekhadra, Farida; Devauchelle, Nicole; Donval, Anne; Dorange, Germaine.
This work is part of the program, "recruitment determinism in scallops" initiated in 1992 by the "Contrat de Baie". The aim of this research was to explain interannual abundance fluctuations observed for Pecten maximus, in the Bay of Brest. To this end an analytical approach to the life cycle of the species was undertaken to determine its critical phases. A phase may be considered as "critical" if the mortality rate at its level varies from one year to the other. Using data from 1989 to 1994, a precise time-table of the "physiological year" of the scallop in the Bay of Brest was determined. Fecundity and gamete production kinetics were estimated from the annual variation in the weight indices of the gonad. In the laboratory, egg quality was estimated...
Tipo: Text
Palavras-chave: Pecten maximus; Recruitment; Reproductive cycle; Digestion.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00044/15495/12861.pdf

Reproduction et recrutement de la coque Cerastoderma edule L. a Saint-Pol-de-Leon (Bretagne Nord)
Provedor de dados: 5
Autores: Guillou, Jean-louis; Tartu, C.
Investigation on the recruitment of Cerastoderma edule was carried out at St-Pol-de-Leon over three years. This approach is intended to disclose in the fluctuations of recruitment the part of variability linked with reproduction and spawning. Stages of sexual maturity are used together with a condition index. The reproductive activity spread out over the most part of the year, ripe individuals being observed even in winter. Main spawning took place in summer and autumn. Seasonal and interannual fluctuations of recruitment are associated with the variations of the condition index. An increase of the reproductive activity could be observed between 1987 and 1989 related with temperature. It is shown that this factor is the main responsible of the variations...
Tipo: Text
Palavras-chave: Cerastoderma edule; Bivalvia; Marine molluscs; Temperature effects; Recruitment; Seasonal variations; Sexual maturity; Reproductive cycle; Spawning; Sexual reproduction.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/acte-1719.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport scientifique annuel du réseau national Velyger, convention DPMA-Ifremer 2016
Provedor de dados: 5
Autores: Pouvreau, Stephane.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 60 à 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage. Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une quinzaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (2003, 2006, 2008, 2012, 2014). A Marennes-Oléron, cette variabilité existe, mais s’avère beaucoup...
Tipo: Text
Palavras-chave: Huître creuse; Naissain; Cycle de reproduction; Captage; Recrutement; Changement climatique; Larves; Pacific oyster; Spat; Recruitment; Seed collecting; Larvae; Reproductive cycle; Climate change.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00433/54427/55776.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport annuel 2014
Provedor de dados: 5
Autores: Pouvreau, Stephane; Petton, Sebastien; Queau, Isabelle; Haurie, Axel; Le Souchu, Pierrick; Alunno-bruscia, Marianne; Palvadeau, Hubert; Auby, Isabelle; Maurer, Daniele; D'Amico, Florence; Passoni, Sarah; Barbier, Claire; Tournaire, Marie-pierre; Rigouin, Loic; Rumebe, Myriam; Fleury, Elodie; Fouillaron, Pierre; Bouget, Jean-francois; Pepin, Jean-francois; Robert, Stephane; Grizon, James; Seugnet, Jean-luc; Chabirand, Jean-michel; Le Moine, Olivier; Guesdon, Stephane; Lagarde, Franck; Mortreux, Serge; Le Gall, Patrik; Messiaen, Gregory; Roque D'Orbcastel, Emmanuelle; Quemener, Loic; Repecaud, Michel; Mille, Dominique; Geay, Amelie; Bouquet, Anne-lise.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage. Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une dizaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple les années 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (les années 2003, 2006, 2008, 2012, 2013). A Marennes-Oléron, cette variabilité existe, mais...
Tipo: Text
Palavras-chave: Huître creuse; Naissain; Recrutement; Captage; Larves; Cycle de reproduction; Changement climatique; Pacific oyster; Spat; Recruitment; Spat collecting; Larvae; Reproductive cycle; Climate change.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00279/38990/37561.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport annuel 2015
Provedor de dados: 5
Autores: Pouvreau, Stephane.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 60 à 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage.  Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une dizaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (2003, 2006, 2008, 2012, 2014). A Marennes-Oléron, cette variabilité existe, mais s’avère beaucoup...
Tipo: Text
Palavras-chave: Huître creuse; Naissain; Recrutement; Captage; Larves; Cycle de reproduction; Changement climatique; Pacific oyster; Spat; Recruitment; Seed collecting; Larvae; Reproductive cycle; Climate change.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00334/44533/44240.pdf

The reproductive cycle of the European clam Ruditapes decussatus (L., 1758) in two Portuguese populations: Implications for management and aquaculture programs
Provedor de dados: 5
Autores: Matias, Domitilia; Joaquim, Sandra; Matias, Ana Margarete; Moura, Paula; Sousa, Joana; Sobral, Paula; Leitao, Alexandra.
The reproductive cycle, as well as its nutrient storage and utilization, of two populations of Ruditapes decussatus from the main production areas of this species: Ria de Aveiro and Ria Formosa Lagoon (Portugal) were studied here over a 24 month period (May 2010-April 2012). The reproductive cycle of both populations of R. decussatus followed an annual cyclicality that comprised a ripe stage in spring followed by a spawning period that began in late spring and extended throughout summer until early autumn. This extended and continuous spawning period may be an advantageous strategy for this species by ensuring a continuous supply of gametes. Moreover, R. decussatus can adopt different reproductive strategies depending on the geographical origin. The...
Tipo: Text
Palavras-chave: European clam; Ruditapes decussatus; Reproductive cycle; Portuguese populations; Biochemical composition; Seasonal variations.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00152/26292/25461.pdf

Rising water temperatures, reproduction and recruitment of an invasive oyster, Crassostrea gigas, on the French Atlantic coast
Provedor de dados: 5
Autores: Dutertre, Mickael; Beninger, Peter G.; Barille, Laurent; Papin, Mathias; Haure, Joel.
The recent appearance and invasion of feral oysters (Crassostrea gigas) along the northern European Atlantic coast, underscores the necessity to investigate the relationship between environmental variables, reproductive physiology, larval development and recruitment. We studied these relationships at both high (HT) and intermediate (IT) - turbidity sites, through historical data on water temperatures, multi-parameter environmental probes, histological analyses, and field collections of planktonic larvae and settled post-larvae in 2005 and 2006. A progressive warming trend was observed, especially since 1995, when oyster proliferation first became severe. Threshold temperatures for oocyte growth, larval development and settlement were achieved in both 2005...
Tipo: Text
Palavras-chave: Aquaculture; Climate warming; Coastal waters; Crassostrea gigas; Reproductive cycle; Oyster larvae; Settlement; Turbidity.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00000/11150/7938.pdf

Reproductive Strategies of Brazilian Lizards of the Genus Tropidurus Rodrigues, 1987 (Squamata, Tropiduridae) in the Temporal and Spatial
Provedor de dados: 77
Autores: Ferreira,Adelina; Kihara,Virginia Ojeda; Mehanna,Mahmoud.
Reproductive strategy is the set of adaptations that promote the most efficient way that the species will survive under the particular conditions of a determined environment. Understanding these adaptations is important and can help pinpoint populations indicator of environmental changes. Spermatogenesis is a measurable biological process of these adaptations in spatial and temporal scales. We analyzed the morphology of the testes and oviducts of the lizard species that comprise the genus Tropidurus, taking into account the geographical distribution and sympatric relations. For the analysis and the testes were removed from the middle part of the oviducts from Tropidurus etheridge, T. oreadicus, T. itambere, T. spinulosus and T. Guarani species, collected...
Tipo: Journal article
Palavras-chave: Reproductive cycle; Lizards; Brazil.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022011000400058

Gonadal steroids levels and vitellogenesis in the formation of oocytes in Prochilodus lineatus (Valenciennes) (Teleostei: Characiformes)
Provedor de dados: 83
Autores: Hainfellner,Patrick; Souza,Thiago Gonçalves de; Moreira,Renata Guimarães; Nakaghi,Laura Satiko Okada; Batlouni,Sergio Ricardo.
The objective of this study was to obtain information about the possible mechanisms related to poor reproductive performance in tropical rheophilic fish. To that effect, cages (Cs) and earthen ponds (EPs) were used as experimental systems to provide unsuitable and suitable conditions, respectively, for curimbatá (Prochilodus lineatus) breeders. Fish were maintained under experimental conditions for 18 months, and during this period females were randomly sampled every two months for biometric analysis (n=30), blood (n=5/sampling) and ovary (n=5/sampling). After this period EPs females (EPFs) and Cs females (CFs) were submitted to the induced breeding experiments. The results showed that rearing curimbatá for such long time in a cage at this stocking...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Reproductive cycle; Spawning performance; Steroid levels; Tropical rheophilic fish.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000300014

Reproductive biology of Triportheus trifurcatus (Castelnau, 1855) (Characiformes: Characidae) in the middle rio Araguaia, MT, Brazil
Provedor de dados: 83
Autores: Martins-Queiroz,Mirian F.; Mateus,Lúcia A. de F.; Garutti,Valdener; Venere,Paulo C.
The study of the reproductive biology of Triportheus trifurcatus of the middle rio Araguaia was carried out using 275 specimens obtained in seven collections conducted in the period between November 2003 and January 2005. Females prevailed among the classes of intermediate length, as well as in the total number of samples. On the other hand, males prevailed in the smaller classes. The average length of females was larger than that of males. Four stages of gonadal maturation were macro- and microscopically identified: B - maturation, C - mature, D - spent and E - resting. Stage A (immature) was not found in the habitats sampled. The smallest-length male was 110 mm in standard length, and the smallest female, 119 mm. The spawning period occurred from...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fecundity; Sex ratio; Reproductive cycle; Gonadal maturation.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000200010

Mobilization of energetic substrates in the endangered catfish Steindachneridion parahybae (Siluriformes: Pimelodidae): changes in annual reproductive cycle in captivity
Provedor de dados: 83
Autores: Tolussi,Carlos E.; Gomes,Aline D.; Ribeiro,Cristiéle da S.; Caneppele,Danilo; Moreira,Renata G.; Honji,Renato M.
ABSTRACT This study aimed at analyzing the energetic substrate (ES) in the main storage tissues of Steindachneridion parahybae, throughout the reproductive cycle in captivity. Differently from wild, in captivity, feeding is not interrupted during the reproductive period, the females do not spawn spontaneously, and they are sedentary. Adult females were sampled monthly and based on their histology and gonadosomatic index (GSI), ovaries were classified into: previtellogenic (PRV), vitellogenic (VTG), and regression (REG) stages. Ovaries at the VTG stage showed higher protein and lipids levels than at the PRV stage with a positive correlation between these substrates and the GSI. Muscle was the main source of proteins transferred to the ovaries, according to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycogen; Lipids; Metabolic substrate; Protein; Reproductive cycle.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000200208

Observations macroscopiques des gonades de deux espèces de Mugilidés: Liza falcipinnis et Mugil cephalus.
Provedor de dados: 20
Autores: Djadji, E.L.G.; Sylla, S.; Atsé, B.C.
L'étude descriptive de ces différents stades de maturation sexuelle nous permettra de mieux cerner l'approche macroscopique des observations. Elle est d'autant plus importante que le dimorphisme sexuel dans cette famille est inexistant et que la détermination du sexe des individus nécessite une dissection.
Tipo: Journal Contribution
Palavras-chave: Fish species; Reproductive cycle.
Ano: 2010
URL: http://hdl.handle.net/1834/5775

Reproductive cycle of edible echinoderms from the Southwestern Indian Ocean:  I. Tripneustes gratilla L. (Echinoidea, Echinodermatata)
Provedor de dados: 20
Autores: Vaïtilingon, D.; Rasolofonirina, R.; Jangoux, M.
The reproductive cycle of the edible echinoid Tripneustes gratilla (Linneaus 1758) was investigated in a population located in the southwest coast of Madagascar (Toliara). The reproductive cycle was followed for two consecutive years (October 1999 to October 2001) and characterised by means of gonad and maturity indices. T. gratilla has an annual reproductive cycle mediated by seawater temperature, day length and feeding activity. The histology of the gonads revealed six different maturity stages grouped in three main reproductive phases: growing and maturing, spawning, and spent and recovering. Reproduction is seasonal. Growing and maturing stages occurred from late summer to early winter correlating with decreasing temperatures and day length. Spawning...
Tipo: Journal Contribution
Palavras-chave: TRIPNEUSTES GRATILLA; Abiotic factors; Sexual maturity; Reproductive cycle; Temperature; Sea water; Maturity; Temperature.
Ano: 2005
URL: http://hdl.handle.net/1834/1133

Reproduction et fécondité du mâchoiron Chrysichthys nigrodigitatus en élévage
Provedor de dados: 20
Autores: Otémé, Ziriga Josué.
Différentes structures d'élevage (bassin en béton, enclos et étangs) ont été testées pour leurs convenance comme structures de ponte. Les bassins en béton et les petits enclos en lagune ont donné les meilleurs résultats quant au nombre de pontes obtenues. Des trois types de réceptacles de pontes testés, les réceptacles avec une petite ouverture (150mm de diamètre) à l'une des deux extrémités ont été préférentiellement utilisés par les poissons. Les géniteurs de C. nigroditatus, une fois matures entrent spontanément dans les réceptacles de ponte pour déposer leurs œufs sans intervention externe humaine. L'étude de la fécondité a permis a permis de déterminer la production d’œufs en fonction de la taille et du poids des individus. La fécondité effective...
Tipo: Journal Contribution
Palavras-chave: Reproductive behaviour; Reproductive cycle; Fish ponds.
Ano: 1993
URL: http://hdl.handle.net/1834/5472

Bio-écologie des cétacés et enjeux de leur conservation pour les Etats côtiers africains comme le Sénégal
Provedor de dados: 20
Autores: Ndao, Ibrahima.
Tipo: Theses and Dissertations
Palavras-chave: Whaling; Anatomy; Morphology (biology); Physiology (fish); Preservation (fishery products); Biodiversity; Baleens; Migrations; Reproductive cycle; Fish consumption; Overfishing; Pollution.
Ano: 2006
URL: http://hdl.handle.net/1834/5005

Cycle sexuel et fécondité du mâchoiron Chrysichthys nigrodigitatus en lagune Ebrié, Côte d'Ivoire.
Provedor de dados: 20
Autores: Otémé, Ziriga Josué.
L'évolution saisonnière du développement des gonades chez les femelles de Chrysichthys nigrodigitatus en lagune Ebrié (Côte d'Ivoire) a été étudiée sur un cycle annuel de reproduction. Sept stades macroscopiques de maturation des gonades ont été identifiés. Ces poissons ne pondent qu'une seule fois durant une saison de reproduction qui s'étend de juillet à novembre. La fécondité potentielle varie entre 4878 et 87724 ovocytes et 5438 et 36257 ovocytes respectivement pour le milieu naturel et le milieu d'élevage. La corrélation entre la fécondité et la longueur du poisson est légèrement plus marquée que celle entre la fécondité et et le poids des gonades
Tipo: Journal Contribution
Palavras-chave: Reproductive cycle; Pond culture.
Ano: 1993
URL: http://hdl.handle.net/1834/5519

Biología reproductiva de algunas especies de la tribu Thenaria (Cnidaria: Anthozoa) en el litoral marplatense
Provedor de dados: 20
Autores: Excoffon, A.C.
Universidad Nacional de Mar del Plata, Facultad de Ciencias Exactas y Naturales (Argentina).
Tipo: Theses and Dissertations
Palavras-chave: Sexual reproduction; Asexual reproduction; Gametogenesis; Reproductive cycle; Embryonic development; Larval development; Comparative studies; Asexual reproduction; Gametogenesis; Embryonic development; Sexual reproduction; Http://aims.fao.org/aos/agrovoc/c_664; Http://aims.fao.org/aos/agrovoc/c_27931; Http://aims.fao.org/aos/agrovoc/c_2545; Http://aims.fao.org/aos/agrovoc/c_26876.
Ano: 1993
URL: http://hdl.handle.net/1834/2957

Historia de vida y dinámica de poblaciones de Lychnorhiza lucerna (Scyphozoa) ¿Un recurso pesquero alternativo?
Provedor de dados: 20
Autores: Schiariti, A.
In this Thesis we presented the first steps in the study of the life history and population dynamics of Lychnorhiza lucerna as well as the possibilities of development of its fishery in Argentina. L. lucerna presented a metagenetic life cycle characteristic of most scyphozoans. Polyps reproduced asexually by the production of podocysts and polidisk strobilation. The combination of both types of asexual reproduction resulted in a high strobilation rates indicating that the abundance of medusae would strongly depend on polyps abundance and reproduction. The absence of ephyrae in the Río de la Plata estuary suggest that L. lucerna doest not complete its life cycle locally but medusae would be produced by polyps located northwards along the Uruguayan or...
Tipo: Theses and Dissertations
Palavras-chave: Life cycle; Life history; Population dynamics; Reproductive cycle; Biomass; Estuarine fisheries; Life history; Biomass; Estuarine fisheries; Life cycle; Population dynamics; Http://aims.fao.org/aos/agrovoc/c_12170; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_2674; Http://aims.fao.org/aos/agrovoc/c_4317; Http://aims.fao.org/aos/agrovoc/c_6111.
Ano: 2008
URL: http://hdl.handle.net/1834/3109

Ciclo reproductivo y fecundidad del lenguado Paralichthys patagonicus Jordan, Jordan y Goss 1889
Provedor de dados: 20
Autores: Macchi, G.J.; Diaz de Astarloa, J.M.
The reproductive characteristics of the flounder (Paralichthys patagonicus)are analyzed on the basis of the microscopic and macroscopic study of the ovaries. Preliminary estimations of the fecundity of this species are also made. The samples were obtained from the monthly commercial langings in Mar del Plata and from research cruises undertaken by the INIDEP. A total of 641 ovaries were studied; 210 of which were selected for the histological analysis. 24 ovaries with hydrated oocytes and without post-ovulatory follicles were used to determine batch fecundity. A macroscopic maturity scale of five stages was established. The histological analysis allowed to introduce three substage within the maturation stage including a partial spawning stage. According to...
Tipo: Journal Contribution
Palavras-chave: Reproductive cycle; Fecundity; Ovaries; Ovaries; Fecundity; Http://aims.fao.org/aos/agrovoc/c_5456; Http://aims.fao.org/aos/agrovoc/c_15725.
Ano: 1996
URL: http://hdl.handle.net/1834/1960

El comportamiento reproductivo del besugo (Pagrus pagrus)en el ecosistema costero bonaerense.
Provedor de dados: 20
Autores: Cotrina, C.P.; Christiansen, H.E.
The species, like other members of the Family Sparidae, has a hermaphroditic phase in its sexual development, affecting the population partially during the first period of life. The sexual differentiation mechanisms have been inferred by the way of macroscopic characterization and proportionality of the different stages observed during the first five year classes. The highest proportion of specimens with bisexual gonads is observed during the third year of life: from the macroscopical point of view, both sexes are equally developed or with predominance of the masculine crest; microscopically, both are functional and synchronous. The masculine portion demostrate a normal expulsion of germ cells and in the ovaric part post-ovulatory and atretic follicles...
Tipo: Journal Contribution
Palavras-chave: Reproductive cycle; Ovaries; Ovaries; Http://aims.fao.org/aos/agrovoc/c_5456.
Ano: 1994
URL: http://hdl.handle.net/1834/1929

Dinámica de la metapoblación de almeja panopea Panopea abbreviata en los golfos norpatagónicos
Provedor de dados: 20
Autores: Zaidman, P.C.
Panopea abbreviata es el molusco bivalvo infaunal de mayor tamaño del Mar Argentino. Se distribuye desde Río de Janeiro (Brasil) hasta la Patagonia Argentina. En los golfos San Matías (GSM) y San José (GSJ), conforma una metapoblación que presenta una distribución discontinua, formada por una serie de poblaciones ubicadas a lo largo de las costas.Es el bivalvo más longevo explotado en el Atlántico Sur. En el GSM su pesquería comenzó en el año 2000 y, si bien la misma es incipiente, debido a las características biológico-poblacionales de P. abbreviata es un recurso que requiere de un manejo precautorio. Excepto por estudios preliminares sobre el crecimiento y el ciclo reproductivo, no se contaba con la información básica para manejo. El objetivo general del...
Tipo: Theses and Dissertations
Palavras-chave: Fishery biology; Marine molluscs; Population dynamics; Sustainable management; Age; Growth; Mortality rate; Recruitment; Population structure; Spatial variations; Sex composition; Reproductive cycle; Histology; Environmental conditions.
Ano: 2013
URL: http://hdl.handle.net/1834/5236

Observaciones sobre el ciclo reproductivo del mero, Acanthistius brasilianus (Serranidae, Pisces)
Provedor de dados: 20
Autores: Dell'Arciprete, O.P.; Christiansen, H.E.; Diaz de Astarloa, J.M.
The present paper deals with the study of the reproductive cycle of the sea-bass (Acanthistius brasilianus). Its main objective is getting some advance in the inderstanding of the gonad cycle of the sea-bass and the comprehension of its mode of reproduction. The study is emphasized on tahe females because it is thought that they permit a better analysis in this first stage of the reseach work. Some basic aspects, such as the anatomical and the histological description of the gonadas, the study of ovocyte maturation phases and the development of ovary maturity scales were into account. The gonad cycle was analized throughout the year by means of different approaches; histological analysis of ovary preparation and by following the statistical structure of...
Tipo: Journal Contribution
Palavras-chave: Sexual maturity; Reproductive cycle; Reproduction; Ovaries; Testes; Ovaries; Sexual maturity; Reproduction; Testes; Http://aims.fao.org/aos/agrovoc/c_5456; Http://aims.fao.org/aos/agrovoc/c_7016; Http://aims.fao.org/aos/agrovoc/c_6507; Http://aims.fao.org/aos/agrovoc/c_7682.
Ano: 1987
URL: http://hdl.handle.net/1834/2004

Estrategias reproductivas de moluscos bivalvos y equinoideos
Provedor de dados: 20
Autores: Calvo, J.; Morriconi, E.; Orler, P.
The theoretical aspects of reproductive strategies and life histories are analyzed. The gonadal structures and the main features of gametogenesis of bivalves and echinoids are described. Research on the reproductive characteristics and gametogenic cycles of the bivalve molluscs in the Argentinian littoral and the echinoid Loxechinus albus is reviewed. Special references to Mytilus edulis, Aulacomya ater, Brachidontes purpuratus, Aequipecten tehuelchus, Zygochlamys patagonica, Ostrea puelchana, Clausinella gayi, Protothaca antiqua, Eurhomalea exalbida and Mesodesma mactroides are made. Analysis of reproductive cycles includes histological and ponderal descriptions of gonadal variations. The main trend found is the partial and multiple spawning episodes....
Tipo: Book Section
Palavras-chave: Hermaphroditism; Gametogenesis; Life cycle; Marine molluscs; Reproduction; Reproductive cycle; Hermaphroditism; Gametogenesis; Life cycle; Reproduction; Http://aims.fao.org/aos/agrovoc/c_3571; Http://aims.fao.org/aos/agrovoc/c_27931; Http://aims.fao.org/aos/agrovoc/c_4317; Http://aims.fao.org/aos/agrovoc/c_6507.
Ano: 1998
URL: http://hdl.handle.net/1834/2581

Reproductive cycle of edible echinoderms from the South-Western Indian Ocean:  II. The sandfish Holothuria scabra (Jaëger, 1833)
Provedor de dados: 20
Autores: Vaïtilingon, D.; Rasolofonirina, R.; Eeckhaut, I.; Jangoux, M.
The reproductive cycle and gonad morphology were investigated in a population of Holothuria scabra (Jaëger, 1833) from Toliara, south-west of Madagascar. Surveys were done from November 1998 to April 2001 by monthly samplings of 30 individuals. There is a single gonad formed by a tuft of numerous ramified tubules. The annual reproductive cycle of the population was determined from monthly variations of the gonad index and the maturity index. Five sexual maturity stages were described. An annual reproductive cycle occurred with most individuals being mature or spawning between November and April. Gametogenesis was not synchronous in the population, but was synchronous in all the tubules of a single gonad except the smallest immature ones (length &lt; 1 cm)....
Tipo: Journal Contribution
Palavras-chave: Reproductive cycle; Spawning.
Ano: 2005
URL: http://hdl.handle.net/1834/1134

Etude de la dynamique de population de &lt;Talitrus saltator&gt; (crustace, amphipode) issu de la plage de Bizerte
Provedor de dados: 20
Autores: Ayari-Akari, A.; Nasri-Ammar, K.
La dynamique de population de l’Amphipode supralittoral Talitrus saltator (Montagu, 1808) a été étudiée mensuellement de juin 2007 à décembre 2008, au niveau de la plage de Bizerte (37°19’17.1”N; 09°51’57.3”E). Durant cette période, 2073 spécimens de Talitrus saltator ont été identifiés. La reproduction est saisonnière, s’étendant de mars à novembre avec une période de repos sexuel pendant l’hiver. La sex-ratio globale est égale à 0,74 révélant ainsi un déséquilibre en faveur des femelles; cependant, au niveau des prélèvements des mois de juillet, août et octobre 2007 et des mois de mai, août et septembre 2008, ce déséquilibre s’inverse en faveur des mâles. En effet, la taille de la ponte augmente avec celle des femelles. Au cours de cette étude, trois...
Tipo: Journal Contribution
Palavras-chave: Reproductive cycle; Marine crustaceans.
Ano: 2013
URL: http://hdl.handle.net/1834/5900

Reproductive biology and histological studies of the grey mullet, liza ramada, (risso, 1826) in lake timsah, suez canal
Provedor de dados: 20
Autores: Ramadan, A.M.; El-Halfawy, M.M.; Mahmoud, W.F.
Reproductive characteristics of Liza ramada in Timsah Lake showed that the male reaches first sexual maturity smaller than the female at a total body length of 14 cm. and 16 cm., respectively. Overall sex ratio is 1: 1.7 for males to females. The gonado-somatic index of males was lower than that of females. Where, the maximum GSI values were recorded in November 5.03 % and 12.4 % for males and females, respectively. The maturity stages of male and female Liza ramada are morphologically separated according to the changes in shape, size and colour of the gonad in different successive stages. These stages are virgin, maturing virgin, developing, developed, gravid and spent stages. Histologically, the oocyte maturation showed the following phases; first growth...
Tipo: Journal Contribution
Palavras-chave: Field study; Histology; Reproductive cycle; Mullet fisheries.
Ano: 2007
URL: http://hdl.handle.net/1834/1905

Reproductive performance of &lt;i&gt;Macrobrachium rosenbergii&lt;/i&gt; females in captivity
Provedor de dados: 27
Autores: Cavalli, R.O.; Lavens, P.; Sorgeloos, P.
The breeding frequency, fecundity, egg hatchability, larval output and viability of pond-reared, mature &lt;i&gt;Macrobrachium rosenbergii&lt;/i&gt; females were individually followed up during 180 d. Sexually mature prawns were maintained under controlled laboratory conditions (28.7 C and 12-h light/d) in a 190-L freshwater recirculation system and fed a formulated diet. Ovarian development, moulting and spawning events were checked daily. At least six consecutive moults were recorded for each of the 18 females. The duration of the intermoult period averaged 27.5 d and was not affected by ovarian development or spawning, but intermoult periods followed by spawning had significantly lower growth rates. From a total of 126 moulting events recorded, egg...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fecundity; Moulting; Prawn culture; Rearing; Recirculating systems; Reproductive cycle; Macrobrachium rosenbergii.
Ano: 2001
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=8494

Reproductive biology of the swamp racer Mastigodryas bifossatus (Serpentes: Colubridae) in subtropical Brazil
Provedor de dados: 103
Autores: Leite,Pedro T.; Nunes,Simone de F.; Kaefer,Igor L.; Cechin,Sonia Z.
The swamp racer Mastigodryas bifossatus (Raddi, 1820) is a large snake of Colubrinae. It is widely distributed in open areas throughout South America. Dissection of 224 specimens of this species housed in herpetological collections of the southern Brazilian states of Rio Grande do Sul, Santa Catarina and Paraná provided information on its sexual dimorphism, reproductive cycle and fecundity in subtropical Brazil. Adult specimens of M. bifossatus average approximately 1190 mm in snout-vent length and females are larger than males. The reproductive cycle of females is seasonal, with secondary vitellogenesis occurring from July to December. However, examination of male gonads did not reveal signs of reproductive seasonality in this sex. Egg laying was recorded...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fecundity; Neotropics; Reproduction; Reproductive cycle; Sexual dimorphism.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702009000100003

Ovarian follicular cycle of Tropidurus hispidus and Tropidurus semitaeniatus (Squamata: Tropiduridae) in a semiarid region of Brazil
Provedor de dados: 103
Autores: Santos,Hellen S.; Santos,Jamile M.S.; Matos,Maria H.T.; Silva,Naisandra B.; Freire,Eliza M.X.; Ribeiro,Leonardo B.
The reproductive cycle of Squamata reptiles is often associated with environmental conditions, such as rainfall. In this respect, seasonal variations may affect the morphology of the ovarian follicles, which are associated with vitellogenesis. The present study describes histological alterations in the ovarian cycle of two lizard species, Tropidurus hispidus (Spix, 1825) and Tropidurus semitaeniatus (Spix, 1825), which inhabit a caatinga region in the state of Rio Grande do Norte. Our goal was to identify morphological differences in the ovarian follicles at each phase of vitelloge nesis and to ascertain if they are associated with rainfall. Three follicular phases were identified in both species: pre-vitellogenesis, vitellogenesis and follicular atresia....
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Ovarian stages; Reproductive cycle; Semiarid; Vitellogenesis.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702015000100086

Ciclo reprodutivo de machos de Liolaemus occipitalis Boulenger (Sauria, Tropiduridae)
Provedor de dados: 104
Autores: Verrastro,Laura; Krause,Lígia.
The aim of this work is to describe the reprodutive cycle of the males of L. occipitalis from the coastal sand-dunes of Rio Grande do Sul State, Brazil. It was carried out between April/86 and March/88, at Jardim Atlântico Beach, Tramandaí, Rio Grande do Sul. These lizards showed reprodutive activity between September and December, with a retreat period during January and February. The seasonality of the reprodutive cycle became fully evident by the monthly variation of the testicular mass, showing an inverse relation with the temperature along the year.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Tropiduridae; Liolaemus; Neotropical lizards; Reproductive cycle.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751999000100019

PHENOLOGY, BIOMETRICS AND FRUITS PRODUCTION OF Attalea nucífera (ARECACEAE) IN COLOMBIA
Provedor de dados: 37
Autores: Jiménez-Morera,Ivon; García,Néstor.
ABSTRACT Attalea nucífera is a threatened palm endemic to the Magdalena River basin in Colombia. In the past its seeds were consumed by the inhabitants of the town of Guaduas, Cundinamarca, although currently its use is less frequent. To assess the productive potential of this palm, we studied its phenology, biometric parameters, and fruit productivity in a forest relict in Guaduas. Field work was carried out between April 2016 and March 2017. The reproductive cycle of this species lasted approximately 12 and a half months from bud to fruit ripening. Although bud production occurred throughout the year, it increased during periods of greatest rainfall. Flowering peaks occurred towards the end of the rainy season and fruits ripened towards the period of low...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conservation; Reproductive cycle; Threatened species; Tropical Dry Forest.
Ano: 2020
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2020000100104

Reproductive biology of Thamnodynastes hypoconia (Serpentes: Dipsadidae) in Brazilian subtemperate wetlands
Provedor de dados: 42
Autores: REBELATO,MARLUCI M.; PONTES,GLÁUCIA M.F.; TOZETTI,ALEXANDRO M.
ABSTRACT This study aimed to describe the reproductive biology of populations of Thamnodynastes hypoconia in subtemperate wetlands based on macroscopic analyses of their gonads. We analyzed 101 specimens from the southernmost regions of Brazil. The males had a greater snout-vent length, but the females reached sexual maturity with a greater body size. The reproductive cycle of the females was seasonal, with secondary vitellogenesis occurring between the winter and spring (May-October). Based on macroscopic analysis of gonads, data suggests that males have a continuous reproductive cycle. Parturition occurs between the late summer and early fall (January-April). The clutch size ranged between 4 and 16 embryos and showed no relationship with the female's...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecology; Pampa; Reproductive cycle; Sexual maturity; Snakes.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000501699

Reproductive biology of a viviparous lizard (Mabuya dorsivittata) from the subtropical Wet Chaco of Argentina: geographical variations in response to local environmental pressures
Provedor de dados: 42
Autores: ORTIZ,MARTÍN A.; BORETTO,JORGELINA M.; IBARGÜENGOYTÍA,NORA R.
Herein we studied the reproductive biology of a viviparous lizard (Mabuya dorsivittata) from the Wet Chaco region (northeastern Argentina) and compared the results with other populations from the Espinal (central Argentina) and the Atlantic Forest (southeastern Brazil), and with other Neotropical species of Mabuya to better understand the possible causes of its reproductive phenotype variation. Males and females of M. dorsivittata from the Wet Chaco exhibited associated, seasonal, and annual reproductive cycles. Spermatogenic activity related positively to a lengthening photoperiod reaching maximum activity in late spring (December). Females displayed an extended gestation period of 11 months, from mid-summer (February) to late spring or early summer...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Reproductive cycle; Sexual dimorphism; Ecotypic variation; Lizard; Squamata.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000100609

Reproduction of a whiptail lizard (Ameivula ocellifera, Teiidae) from a coastal area in northeastern Brazil
Provedor de dados: 42
Autores: ZANCHI-SILVA,DJAN; BORGES-NOJOSA,DIVA M.; GALDINO,CONRADO A.B.
The reproductive ecology of Ameivula ocellifera was studied from September 2009 to August 2010 in a coastal area of the state of Ceará, Brazil. Females reproduced continuously throughout the year, with a peak at the end of the rainy season. Even though there was a predominance of pre-reproductive individuals in the sample, gonadal activity of males peaked synchronously to female reproduction. Mean clutch size was 1.98 ± 0.56 and positively associated with female body size, while mean egg volume was 510.54 ± 84.29 mm3 and unrelated to female body size. We did not find any association between clutch size and average egg volume.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ameivula; Cnemidophorus; Life history; Reproductive cycle.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000301263

Diet, sexual dimorphism and reproduction of sympatric racers Philodryas aestiva and Philodryas patagoniensis from the coastal Brazilian Pampa
Provedor de dados: 42
Autores: QUINTELA,FERNANDO M.; LOEBMANN,DANIEL.
Abstract: Herein we investigated diet, sexual dimorphism and reproductive biology of two sympatric congeneric species at the coastal Brazilian Pampa, Philodryas aestiva and P. patagoniensis. Analysis of the stomach content of the scansorial Philodryas aestiva revealed that it feeds mainly on Anura and small mammals, while it occasionally consumes Insecta, Squamata and Aves. The more terrestrial Philodryas patagoniensis presented a broader diet, composed mainly of Anura, Squamata and small mammals. Insecta and Actinopterygii were found in lower frequencies. In females of both species, snout-vent length was significantly larger than in males, while tail length/snout-vent length ratio was significantly higher in males. Males reach sexual maturity at smaller...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Feeding habits; Natural history; Neotropical snakes; Fecundity; Reproductive cycle.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000100633

Population dynamics and reproductive biology ofAchatina fulica Bowdich, 1822 (Mollusca, Gastropoda) in Salvador - Bahia
Provedor de dados: 49
Autores: Silva,Eder Carvalho da; Omena,Elianne Pessoa.
The risks following introduction of invasive species are enormous and incalculable. Achatina fulica is considered one of the 100 species of greatest invasive potential, stands out among the land pulmonate snails, mostly for its high reproductive potential that accelerates the process of dispersion, increasing the damages related to health (disease transmission), to economy (crops destruction) and to environment (biodiversity loss). In order to investigate the relationship of the African snail with the environment, trying to relate sexual activity with climatic variables (temperature, rainfall and humidity), a study was conducted on aspects of population dynamics and reproductive biology in Salvador city. The snails were collected by hand, monthly....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bioinvasion; Invasive species; Reproductive cycle; Growth; Giant African snail.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032014000300115

Reproduction of the greater bulldog bat Noctilio leporinus (Chiroptera: Noctilionidae) in a mangrove area in southern Brazil
Provedor de dados: 49
Autores: Bordignon,Marcelo Oscar; França,Adriana de Oliveira.
The reproductive pattern of the greater bulldog bat (Noctilio leporinus) was studied in southern Brazil from January to December 1999. The morphological characteristics of their reproductive organs were recorded monthly, through histological analysis of testes and ovaries. Those data were correlated with forearm size and body mass, as well as with external reproductive characteristics. The diameter of the seminiferous tubule increased proportionately to testis mass and body weight, and larger males had greater testis mass. Sexually mature males were recorded throughout the year. Ovary histology revealed that females ovulate between July and December. Lactating females were recorded in nearly every month of the year. Noctilio leporinus has a bimodal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquatic systems; Neotropics; Reproductive cycle; Seminiferous tubules; Testis mass.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032012000400006

Reproductive biology of Oligosarcus argenteus (Gunther, 1864) adult males and description of the gonadal maturation stages
Provedor de dados: 52
Autores: Matt,Sérgio Luis Pinto da; Gomes,Marcos de Lucca Moreira; Andrade,Dálcio Ricardo de.
Oligosarcus argenteus belongs to the Acestrorhynchinae subfamily, being restricted to South America, and found in several Brazilian hydrographic basins, in lotic and lentic environments, where they are able to reproduce. With the purpose of studying the reproductive biology of the males from this species, many morphological parameters were analyzed during a 24 month period, as well as characterizing the different testicular maturation stages. A maturity scale, with three stages (I - Initial Maturing, II - Intermediate Maturing, III - Final Maturing) was proposed for the adult males of Oligosarcus argenteus. The reproductive period was established by the bimonthly frequency of spermatogenesis and by the gonadal maturation stages.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Reproductive cycle; Histology; Testis; Oligosarcus argenteus.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000100016

Plasma testosterone and 11-ketotestosterone levels of male pacu Piaractus mesopotamicus (Cypriniformes, Characidae)
Provedor de dados: 56
Autores: Gazola,R.; Borella,M.I.
The levels of testosterone (T) and 11-ketotestosterone (11-KT) of the South American pacu Piaractus mesopotamicus were determined by radioimmunoassay during two stages of the reproductive cycle, i.e., resting and maturation, and the gonadosomatic index (GSI) was calculated. The highest levels of T and 11-KT were reached during the maturation stage (T = 2400 ± 56 pg/ml; 11-KT = 2300 ± 60 pg/ml) and lower levels were maintained during the resting period. The rise in androgen levels occurred with the appearance of spermatozoa in the maturation stage, when GSI was highest
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Teleost fish; Testosterone; 11-ketotestosterone; Radioimmunoassay; Reproductive cycle.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997001200017