Navegando por Assunto "Saimiri sciureus"

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Acesso aberto (Open Access)
Análise imunohistológica e desenvolvimento folicular após auto-transplante de tecido ovariano de macaca de cheiro Saimiri collinsi
(Universidade Federal do Pará, 2014-12-11) SCALERCIO, Sarah Raphaella Rocha de Azevedo; DOMINGUES, Sheyla Farhayldes Souza; http://lattes.cnpq.br/2794753357251149; SANTOS, Regiane Rodrigues dos; http://lattes.cnpq.br/0500967766886604
The main objective of the present work was to study ovarian folliculogenesis in Saimiri sciureus. Therefore, we evaluated the expression of intra-ovarian factors related with the follicular development, inhibition and cell proliferation, as well as investigation the effects of pretreatment with vitamin E analogue, Trolox, on the viability and follicular function, apoptosis index, cell proliferation, vascularization and fibrosis after auto-transplanted of fresh ovarian tissue. It was possible for the first time imuno localize proteins expressed as: growth and differentiation factor -9 (GDF -9), c- kit/Kit Ligand and Ki-67 and confirm the expression of anti-Mullerian Hormone (AMH) in different stages of follicular development in squirrel monkey ovary. Regarding pre-incubation with the Trolox antioxidant, it can improves follicular survival after autotransplantation, decrease apoptosis rates in stromal cells, although increase areas of fibrosis after graft. Our results suggest that fresh ovarian tissue can be grafted and incubated without major impact on early follicular growth and morphology after subcutaneous autotransplantation for a short-term. We believe that our results provide an important contribution to understanding the process of folliculogenesis in neotropical monkeys. This knowledge is an important tool to evaluate follicular viability and functionality after cryopreservation of ovarian tissue transplantation and in vitro culture of early follicles, especially for animals at risk of extinction and women that are undergoing to chemotherapy and radiation with risk of loss fertility.
Acesso aberto (Open Access)
Biometria testicular, caracterização e congelamento de sêmen de macacos-de-cheiro de vida livre (Saimiri vanzolinii, S. cassiquiarensis e S. macrodon) e cativeiro (S. Collinsi) em água de coco em pó (ACP-118®)
(Universidade Federal do Pará, 2014-06-24) OLIVEIRA, Karol Guimarães; DOMINGUES, Sheyla Farhayldes Souza; http://lattes.cnpq.br/2794753357251149
Recently, Saimiri sciureus taxon (squirrel monkey) was revised and some subspecies are now classified by some authors as species, for example: Saimiri collinsi, S. cassiquiarensis and S. macrodon. Phenotypically these species are well determined. However, information on reproductive aspects is still quite scarce. The objective of the first phase of this study was to describe and correlate the testis with the seminal quality from captive (S. collinsi) and free-living (S. vanzolinii, S. cassiquiarensis and S. macrodon) squirrel monkeys. Length, width, height, circumference and testicular volume were measured as well as motility, vigour, plasma membrane integrity and morphology, for correlation data. No difference was observed between the right and left testicles within species, neither difference between species concerning to testicular measures. Semen, which was collected by electroejaculation with rectal probe, was constituted by a coagulated fraction, a liquid fraction or both. Seminal quality was similar among species. There is no correlation between testicular volume and seminal volume (of liquid or coagulated fraction) in S. collinsi and S. vanzolinii. The second phase of this work aimed to propose a semen freezing protocol in an extender based in ACP- 118® (powdered coconut water), testing two glycerol concentrations (1.5 and 3%) for captive S. collinsi. The third phase aimed to test a semen cooling protocol without addition of egg yolk (extracellular cryoprotector) followed by freezing with the best glycerol concentration observed in the preceding experiment and apply these protocols, previously tested in captive S. collinsi, in free-living males from S. vanzolinii, S. cassiquiarensis and S. macrodon in field conditions. Semen from S. collinsi could be cooled in ACP-118® without egg yolk. The freezing protocol developed proved to be useful for semen cryopreservation of S. Collinsi, although requiring improved to allow better maintenance of sperm quality after thawing. The procedure proved to be also applicable under field conditions on free-living animals, providing very encouraging results for the formation of genebanks for species vulnerable to extinction as the S. vanzolinii.
Acesso aberto (Open Access)
Desenvolvimento do dimorfismo sexual nos macacos-de-cheiro (Saimiri VOIGT, 1831)
(Universidade Federal do Pará, 2005) MUNIZ, Izaura da Conceição Magalhães; SILVA JÚNIOR, José de Sousa e; http://lattes.cnpq.br/4998536658557008
The squirrel monkeys Saimiri Voigt, 1831 are arboreal and agile primates with a relatively small body as compared to other New World primates. The species are distributed in the Amazon and part of Central America. Several investigations were contucted in order to stablish the taxonomic groups in Saimiri. However, the results of these investigations showed an amount of divergences as to the classification, taxon validity as well as the taxonomic status. In this genus, there are sexual differences with regard to the pattern of coloration of skin, size and form of canine teeth and in the annual spermatogenic cycle in males that characterises the fatted condition due to the deposition of subcutaneuos fat. During this period, the males present an increase in weight ranging from 15 to 20%. The present study aimed to analyse the sexual dimorfism in Saimiri sciureus, comparing the results with other five species of the genus Saimiri (S. cassiquiarensis, S. juruanus, S. ustus, S. boliviensis e S. vanzolinii). A total of 610 specimens were analysed from the collections of the Museu Paraense Emílio Goeldi (MPEG), Museu Nacional, Universidade Federal do Rio de Janeiro (MNRJ) and Museu de Zoologia da Universidade de São Paulo (MZUSP). The age classes were determined according to the morphology of the dental arch described on the basis of the eruptive sequence of deciduous and permanent teeth. Data on chromatic characteristics were collected to analyse the preauricular patch of females in relation to the process of dental eruption, cranial morphology to verify the sexual and age differentiation. In addition, twenty one cranial measurements were perfomed using the Student t-test. There were no differences in the coloration of the skin among the sexual classes up to the adult age in any sexes. There were no differences in the coloration of the skin among the age classes in males. The blackish preauricular patch is an exclusive trait of adult females, however it is not related to ontogeny. The beginning of the sexual dichromatism of the skin is not associated with the rising of dimorfism in cranial morphology, specially of teeth. Macroscopic sexual differences such as size and morphology of cranium, morphology of face, bizygomatic distance and morphology of jaw could be observed from the subadult age. The findings indicated that the sexual dimorfism for the species analysed is better observed in the variables related to the mastigatory apparatus. Moreover, sexual differences in the mophology of cranial bones could be clearly identified among subadult individuals of any taxon. The males were bigger than females from the subadult age onwards and the most conspicuous characteristic of the sexual dimorfism is the cranium length. The species differ from each other because they presented an exclusive or a group of morphometric variables demonstrating the sexual dimorfism.
Acesso aberto (Open Access)
Ecologia, comportamento e associações poliespecíficas do macaco-de-cheiro (Saimiri sciureus), Amazônia Oriental
(Universidade Federal do Pará, 2010) MAGALHÃES, Tatyana Pinheiro; LOPES, Maria Aparecida; http://lattes.cnpq.br/3377799793942627