Consulta: subjectFacets:"Spermatozoon"
Registros recuperados: 8
Data/hora: 10/06/2024 15:15:21

Marine fish spermatozoa: racing ephemeral swimmers
Provedor de dados: 5
Autores: Cosson, J; Groison, A; Suquet, Marc; Fauvel, Christian; Dreanno, Catherine; Billard, R.
After along period of spermatogenesis (several weeks to months), marine fish spermatozoa are delivered at male spawning in seawater (SW) at the same time as ova. In some fish species, as the ova micropyle closes quickly after release, these minute unicells, the spermatozoa, have to accomplish their task of reaching the micropyle within a very brief period (several seconds to minutes), for delivery of the haploid male genetic information to the ova. To achieve this goal, their high-performance motile equipment, the flagellum, must fully activate immediately on contact with the SW and then propel the sperm cell at an unusually high initial velocity. The cost of such 'hyperactivity' is a very rapid consumption of intracellular ATP that outstrips the supply....
Tipo: Text
Palavras-chave: Cell activation; Osmolality; Ions; Cell energetics; Motility; Spermatozoon; Marine fish.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6967.pdf

Morphology, morphometry and ultrastructure of the Amazonian manatee (Sirenia: Trichechidae) spermatozoa
Provedor de dados: 103
Autores: Amaral,Rodrigo S.; Lucci,Carolina M.; Rosas,Fernando C. W.; Silva,Vera M. F. da; Báo,Sônia N.
This study describes the morphological, morphometric and ultrastructural characteristics of the Amazonian manatee Trichechus inunguis (Natterer, 1883) spermatozoon. The spermatozoa were obtained from a urine sample of an adult T. inunguis kept in captivity. The spermatozoa were analyzed by light and transmission electron microscopy. The head of Amazonian manatee spermatozoa had a flat oval shape and a well distinguishable midpiece. The mean dimensions of the spermatozoa were: head length, 7.49 ± 0.24 µm; head width, 3.53 ± 0.19 µm; head thickness, 1.61 ± 0.13 µm; midpiece length, 11.36 ± 0.34 µm; flagellum length, 40.91 ± 1.94 µm; total tail length, 52.16 ± 1.06 µm; total spermatozoon length, 60.08 ± 1.40 µm. The Amazonian manatee spermatozoa were similar...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anatomy; Reproduction; Sirenians; Spermatozoon; Trichechus inunguis.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702010000600025

Effect of adenosine concentration on quality of cooled ram semen
Provedor de dados: 96
Autores: Bezerra,Andréia Santana; Nascimento,Thialla Emille Costa do; Castilho,Erick Fonseca de; Gonçalves,Natália Larissa Cunha; Silva,Sillas Matteus Batista Soares da; Cardoso,Aline Serrão; Souza,Heloíse Karine Rolim de; Rodrigues,Luiz Fernando de Souza.
ABSTRACT This study analyzed the adenosine concentration on quality of ram semen in different refrigerated storage times at 5 °C. The design was in blocks with repeated-measures factorial design. Five levels of adenosine and four refrigeration times were considered as fixed effects and the animal as random effect (block). Ram semen was diluted with Andromed® diluent (control) and increasing adenosine levels (0.5, 0.75, 1, and 1.5%). The samples were taken from refrigeration after 4, 8, 12, and 16 h and evaluated for progressive rectilinear sperm motility, sperm vigor, and membrane integrity (supravital test). Data were subjected to analysis of variance with Tukey's test. The regression analysis was conducted to evaluate behavior of adenosine levels. Factor...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Nucleoside; Oxidative stress; Purinergic; Reproduction; Spermatozoon.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982019000100606

Estrutura fina do espermatozóide de Acestrorhynchus falcatus Bloch (Teleostei, Characidae) da região norte do Brasil
Provedor de dados: 104
Autores: Matos,Edilson; Matos,Patricia; Corral,Laura; Azevedo,Carlos.
Spermatozoa of amazon fish, Acestrorhynchus falcatus Bloch, 1794 were investigated by optical microscopy (DIC) and electron microscopy (TEM). Spermatozoa have no acrosome, the head is ovoid, and the midpiece region cylindrical, contains spherical mitochondria. The centriolar complex is located at the lateral side of the nucleus, formed by nine peripheral pairs of microtubules and arranged in a right angle to each other. The flagellum consists of nine pairs of peripheral and two central microtubules.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Teleostei; Characidae; Acestrorhynchus falcatus; Ultrastructure; Spermatozoon.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752000000300019

Estrutura fina do espermatozóide de Mellita quinquiesperforata Leske (Echinodermata) do litoral norte do Brasil
Provedor de dados: 104
Autores: Matos,Edilson; Matos,Patricia; Corral,Laura; Azevedo,Carlos.
The fine structure of the spermatozoon in the Mellita quinquiesperforata Leske, 1778 was studied. Collected from the Amazon region, were described by light and transmission electron microscopy. The spermatozoon consisted of a acrosome complex, nucleus, four to six mitochondria, two centrioles and flagellum. The acrosome was composed of a acrosome complex, the acrosomal vesicle and the subacrosomal space. The nucleus are composed by dense material. The middle piece contains 4-6 mitochondria which are arranged around the centrioles, the 9p+0, whose axoneme has the classic 9p+2 microtubular construction.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Equinodermata; Mellita quinquiesperforata; Ultrastructure; Spermatozoon.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752000000300018

Buserelin acetate-induced spermiation in Leptodactylus ocellatus and evaluation of semen characteristics - doi: 10.4025/actascibiolsci.v35i1.14777
Provedor de dados: 3
Autores: Pereira, Marcelo Maia; Universidade Federal de Viçosa; Ribeiro Filho, Oswaldo Pinto; Universidade Federal de Viçosa; Zanuncio, Jose Cola; Universidade Federal de Viçosa; Troni, Allan Reis; Universidade Federal de Viçosa; Navarro, Rodrigo Diana; Universidade de Brasília; Takamura, Angela Emi; Universidade Federal de Viçosa.
By understanding the hormonal action behind the induction of spermiation in Leptodactylus ocellatus can help in the collection of semen for artificial insemination and cryopreservation. The experiments were conducted at the Experimental Frog Farm of the Federal University of Viçosa. Seven L. ocellatus males with the following secondary sexual characteristics were selected: black thorns, developed forelimbs, and amplexus reflex. Spermiation was induced in these animals by applying daily 0.4 μg buserelin acetate hormone (GnRHa) for 7 days, being the semen collected 90 min after the application. The volume, color, vigor, motility, sperm concentration, and spermatozoa morphology were subsequently evaluated. Three animals responded to GnRHa induction, enabling...
Tipo: Estudos morfológicos
Palavras-chave: 2.04.06.00-2; 5.05.04.00-2; 5.06.03.00-0 creole frog; GnRHa; Semen; Spermatozoon; Sperm motility Aquicultura.
Ano: 2012
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/14777

Use of aqueous extract of noni in extender for sheep semen freezing
Provedor de dados: 45
Autores: Nascimento,A.L.C.; Santos,A.D.F.; Azevedo,H.C.; Velarde,J.M.D.S.; Lima,C.A.; Pereira,M.A.; Pinheiro,G.O.; Gomes,L.C.
ABSTRACT The study aimed to evaluate the action of aqueous extract of noni in an extender for sheep semen freezing. Treatments differed in inclusion of aqueous extract of noni in the extender: T1 ˗ no addition; T2 ˗ 24µg/mL; T3 ˗ 72µg/mL; and T4 ˗ 120µg/mL. Ejaculates were collected, diluted in the four treatments, and frozen. After thawing, the semen was subjected to a thermoresistance test and evaluated for subjective motility, vigor, membrane integrity assessment by hypo-osmotic swelling test, live-dead assay, computer-assisted sperm analysis and the status of sperm capacitation and acrosome reaction. Data were subjected to ANOVA, and then to Student Newman Keuls’s test at 5% significance level. In the thermoresistance test after two hours of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Concentrations; Lipid peroxidation; Plasma membrane; Spermatozoon.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352018000501547

Structural and ultrastructural characterization of zebu (Bosindicus) spermatozoa
Provedor de dados: 47
Autores: Aquino Luque,Maria Carolina; Báo,Sônia Nair.
The ultrastructure of normal, ejaculated spermatozoa of Bos indicus was studied by means of electron microscopy, being evaluated in two principal parts, the head and the tail. The head is flat, oval or paddle-shaped with a square base, which provides a concave recess for the insertion of the tail. The acrosome tightly covers the anterior two thirds of the nucleus. A distinct unilateral acrosomal bulge was observed along the apical edge of the head. The equatorial region demarcates the acrosome from the post-equatorial region that covers the caudal one third of the nucleus. The classical 9+9+2 fiber pattern which composes the axoneme was observed along three segments of the tail, namely middle, principal and terminal pieces. The axoneme is anteriorly bound...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Spermatozoon; Ultrastructure; Bos indicus.
Ano: 2006
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452006000100005