Seasonal variations in gonadosomatic index and seminal quality of squirrel monkeys (Saimiri collinsi).

BACKGROUND: We hypothesized that seasonal variations in testicular biometry in Saimiri collinsi are influenced by body mass and that testicular enlargement is related to improved seminal quality. Therefore, the gonadosomatic index (GSI) can be a tool to determine reproductive seasons and the predictors of seminal quality. METHODS: Body mass, testicular biometry, and semen samples were obtained from eight adult males monthly and evaluated. RESULTS: In the non-fattening/non-reproductive season, the body mass and GSI decreased and increased, respectively, in the fattening. A positive correlation was only observed between the GSI and seminal volume. During fattening, high seminal volume and normal morphology were observed, but sperm concentrations were low. CONCLUSION: The GSI cannot be used as a predictor of seminal quality, but selective pressure to improve seminal quality may increase the chances of fertilization at fattening. The GSI provides new information on seasonality and can be used to identify reproductive seasons in squirrel monkeys.

Morphological and ultrastructural changes in seminal coagulum of the squirrel monkey (Saimiri collinsi Osgood, 1916) before and after liquefaction.

Studies with squirrel monkey semen are of special interest due to the large amount of coagulation that is a component of the semen, which is a problem that has to be overcome when the objective is harvesting of gametes. In the present study, there was characterization of the seminal coagulum of captive S. collinsi. Four samples of ejaculates were collected using electroejaculation procedures from four animals. The aim in conducting this study was to evaluate seminal coagulum of S. collinsi using histological and scanning electron microscopy (SEM) procedures before and after semen liquefaction in an ACP-118® extender. Seminal coagulum of S. collinsi was composed of a superficial plate (external), which coats the spongy seminal plasma matrix of S. collinsi. Additionally, there were sperm in the external and internal components of the coagulum with these gametes being isolated or grouped and with there being a heterogeneous distribution of gametes. The supplementation of semen with ACP-118® resulted in a partial dissolution of the seminal plate and spongy matrix portions of the seminal coagulum within the first hour of incubation.

Estudo preliminar da morfometria da cabeça espermática do macaco-de-cheiro de vida livre / Preliminary study of the spermatic head morphometry of free living Ecuadorian Squirrel Monkey

The objective of this study was to describe and compare the head morphometry of normal and pathological sperm from Saimiri macrodon. In the morphological analysis, 39% of the sperm had normal morphology, and 61% had major or minor defects, with pathology in the tails being the most frequent with 47% (38% curled tail, 7% folded tail and 2% strongly folded tail). Among the evaluated head morphometry parameters, area (A), width (L) and ellipticity (E) showed statistical difference (p>0.05) between normal and pathological sperm. The average head area and width was lower in normal sperm (p=0,01 e p=0,04, respectively), and the mean ellipticity was higher (p=0,038), when compared to pathological sperm. This definition of the sperm morphometric parameters of S. macrodon is important for the samples selection destined to reproduction biotechnologies and for the clarification of taxonomic and evolutionary issues in the genus Saimiri.

Biotecnologias da reprodução sob a perspectiva dos machos de primatas neotropicais: contribuições para a conservação de espécies ameaçadas de extinção / Reproduction biotechnologies for neotropical primate males and contributions to the conservation of endangered species

As biotecnologias da reprodução animal são uma alternativa para a conservação ex situ de espécies de primatas neotropicais ameaçados de extinção, e também podem ser utilizadas como uma ferramenta para o estudo da sua biologia reprodutiva. O entendimento dos mecanismos pré/pós copulatórios e pós-fertilização em primatas neotropicais podem auxiliar no sucesso do estabelecimento de protocolos de criopreservação seminal, visto que são necessários estudos de acordo com as especificidades fisiológicas de cada espécie. No intuito de realizar uma reflexão a acerca do papel do macho no tocante as biotecnologias da reprodução, esta revisão busca destacar os avanços e perspectivas a esse respeito, bem como as principais particularidades no tocante a manipulação do sêmen desses animais, visando uma reflexão acerca de melhorias de protocolos já estabelecidos, e fornecer uma referência para estudos futuros em primatas neotropicais.

The biotechnologies of animal reproduction are an alternative for the ex situ conservation of neotropical primates in some degree threatened with extinction, and could also be used as a tool for the study of reproductive biology. Understanding the pre/post copulatory and post-fertilization mechanisms in neotropical primates can help in the successful establishment of seminal cryopreservation protocols, since studies are necessary according to the physiological specificities of each species. In order to reflect on the role of the male in the reproductive biotechnologies, this review aim to highlight the advances and perspectives, as well as the main particularities with the manipulation of the semen in this animals, aiming at a reflection of improvements to already established protocols, and provide a reference for future studies in neotropical primates.

Análise morfométrica da cabeça espermática em Saimiri cassiquiarensis / Morphometric analysis of the sperm head in Saimiri cassiquiarensis

The objective was to evaluate the sperm morphometry between normal and pathological cells in Saimiri cassiquiarensis aiming at the future use of data in CASA (Computer Assisted Sperm Analysis). Semen was collected from a male (S. cassiquiarensis) by electroejaculation. After collection, a smear in the proportion of 1:1 (semen and eosin-nigrosin stain) was performed, and 100 sperm were measured and morphologically classified as normal and pathological defects (major and minor). Of the total sperm analyzed, 48% were classified as normal and 52% pathological. Of the pathologies, the most frequent was a folded tail (40%), followed by a strongly folded tail (5%), curled tail (2%) and isolated head (5%). The morphometric data showed no statistical difference (p<0.05) between normal and pathological defects. This is the first description for the sperm morphometry in Saimiri cassiquiarensis, therefore, from this database, future assessments at CASA can be conducted for this species.

Biotecnologias da reprodução sob a perspectiva dos machos de primatas neotropicais: contribuições para a conservação de espécies ameaçadas de extinção / Reproduction biotechnologies for neotropical primate males and contributions to the conservation of endangered species

As biotecnologias da reprodução animal são uma alternativa para a conservação ex situ de espécies de primatas neotropicais ameaçados de extinção, e também podem ser utilizadas como uma ferramenta para o estudo da sua biologia reprodutiva. O entendimento dos mecanismos pré/pós copulatórios e pós-fertilização em primatas neotropicais podem auxiliar no sucesso do estabelecimento de protocolos de criopreservação seminal, visto que são necessários estudos de acordo com as especificidades fisiológicas de cada espécie. No intuito de realizar uma reflexão a acerca do papel do macho no tocante as biotecnologias da reprodução, esta revisão busca destacar os avanços e perspectivas a esse respeito, bem como as principais particularidades no tocante a manipulação do sêmen desses animais, visando uma reflexão acerca de melhorias de protocolos já estabelecidos, e fornecer uma referência para estudos futuros em primatas neotropicais.(AU)

The biotechnologies of animal reproduction are an alternative for the ex situ conservation of neotropical primates in some degree threatened with extinction, and could also be used as a tool for the study of reproductive biology. Understanding the pre/post copulatory and post-fertilization mechanisms in neotropical primates can help in the successful establishment of seminal cryopreservation protocols, since studies are necessary according to the physiological specificities of each species. In order to reflect on the role of the male in the reproductive biotechnologies, this review aim to highlight the advances and perspectives, as well as the main particularities with the manipulation of the semen in this animals, aiming at a reflection of improvements to already established protocols, and provide a reference for future studies in neotropical primates.(AU)

Análise morfométrica da cabeça espermática em Saimiri cassiquiarensis / Morphometric analysis of the sperm head in Saimiri cassiquiarensis

The objective was to evaluate the sperm morphometry between normal and pathological cells in Saimiri cassiquiarensis aiming at the future use of data in CASA (Computer Assisted Sperm Analysis). Semen was collected from a male (S. cassiquiarensis) by electroejaculation. After collection, a smear in the proportion of 1:1 (semen and eosin-nigrosin stain) was performed, and 100 sperm were measured and morphologically classified as normal and pathological defects (major and minor). Of the total sperm analyzed, 48% were classified as normal and 52% pathological. Of the pathologies, the most frequent was a folded tail (40%), followed by a strongly folded tail (5%), curled tail (2%) and isolated head (5%). The morphometric data showed no statistical difference (p<0.05) between normal and pathological defects. This is the first description for the sperm morphometry in Saimiri cassiquiarensis, therefore, from this database, future assessments at CASA can be conducted for this species.(AU)

O coágulo seminal de primatas neotropicais sob diferentes abordagens biológicas / The seminal coagulum of neotropical primates under different biological approaches

Após a ejaculação o sêmen de primatas pode coagular em consistência variável, dependendo da espécie. Tanto em termos biológicos quanto em aspectos relacionados à manipulação in vitro para fins de desenvolvimento de biotécnicas reprodutivas, a coagulação seminal é tratada por muitos pesquisadores como um evento intrigante, no qual muitas questões básicas que envolvem a constituição e função do coágulo seminal na reprodução neste grupo de mamíferos, incluindo os primatas neotropicais, ainda permanece em aberto. A fim de reunir informações até hoje divulgadas sobre conceito, mecanismos fisiológicos, grupamentos moleculares e aspectos evolutivos relacionados à coagulação seminal, este texto-base busca destacar o progresso e as lacunas nas pesquisas a esse respeito, bem como as particularidades relacionadas aos símios da Amazônia.

After ejaculation, the semen of primates can coagulate in variable consistency, depending on the species. Both in biological terms and in aspects related to in vitro manipulation for the purpose of developing reproductive biotechniques, seminal coagulation is treated by many researchers as an intriguing event in which many basic issues involving the constitution and function of the seminal coagulum in reproduction in this group of mammals, including the neotropical primates, still remains open. In order to gather information to date on concepts, physiological mechanisms, molecular clusters and evolutionary aspects related to seminal coagulation, this basic text seeks to highlight progress and gaps in research in this regard, as well as the particularities related to Amazonian monkeys.

O coágulo seminal de primatas neotropicais sob diferentes abordagens biológicas / The seminal coagulum of neotropical primates under different biological approaches

Após a ejaculação o sêmen de primatas pode coagular em consistência variável, dependendo da espécie. Tanto em termos biológicos quanto em aspectos relacionados à manipulação in vitro para fins de desenvolvimento de biotécnicas reprodutivas, a coagulação seminal é tratada por muitos pesquisadores como um evento intrigante, no qual muitas questões básicas que envolvem a constituição e função do coágulo seminal na reprodução neste grupo de mamíferos, incluindo os primatas neotropicais, ainda permanece em aberto. A fim de reunir informações até hoje divulgadas sobre conceito, mecanismos fisiológicos, grupamentos moleculares e aspectos evolutivos relacionados à coagulação seminal, este texto-base busca destacar o progresso e as lacunas nas pesquisas a esse respeito, bem como as particularidades relacionadas aos símios da Amazônia.(AU)

After ejaculation, the semen of primates can coagulate in variable consistency, depending on the species. Both in biological terms and in aspects related to in vitro manipulation for the purpose of developing reproductive biotechniques, seminal coagulation is treated by many researchers as an intriguing event in which many basic issues involving the constitution and function of the seminal coagulum in reproduction in this group of mammals, including the neotropical primates, still remains open. In order to gather information to date on concepts, physiological mechanisms, molecular clusters and evolutionary aspects related to seminal coagulation, this basic text seeks to highlight progress and gaps in research in this regard, as well as the particularities related to Amazonian monkeys.(AU)

Contribuições da biotecnologia da reprodução sobre os desafios na manipulação do semên de primatas do gênero Saimiri / Reproductive biotechnology contributions on the challenges of semen manipulation in primates of the Saimiri genus

Algumas espécies de primatas do gênero Saimiri estão classificadas como vulneráveis ou quaseameaçadas. Diante desta realidade, é necessária a aplicação de alternativas para a conservação ex situ (emcativeiro) desses primatas, sobretudo o desenvolvimento de biotécnicas voltadas para a reprodução. Desta forma,o presente trabalho objetivou compilar informações, em linhas gerais, a respeito dos desafios, avanços eperspectivas em relação às pesquisas desenvolvidas no tocante à biotecnologia da reprodução em machos do gênero Saimiri.

Some species of Saimiri primates are classified as vulnerable or near threatened with extinction. Facingthis reality, it is necessary to apply alternatives for the ex situ conservation (in captivity) of these primates,especially the development of biotechniques of reproduction. In this way, the present study aimed to compileinformation, in general terms, regarding the challenges, advances and perspectives in relation to the researchesdeveloped regarding the biotechnology of reproduction in males of the genus Saimiri.

Contribuições da biotecnologia da reprodução sobre os desafios na manipulação do semên de primatas do gênero Saimiri / Reproductive biotechnology contributions on the challenges of semen manipulation in primates of the Saimiri genus

Algumas espécies de primatas do gênero Saimiri estão classificadas como vulneráveis ou quaseameaçadas. Diante desta realidade, é necessária a aplicação de alternativas para a conservação ex situ (emcativeiro) desses primatas, sobretudo o desenvolvimento de biotécnicas voltadas para a reprodução. Desta forma,o presente trabalho objetivou compilar informações, em linhas gerais, a respeito dos desafios, avanços eperspectivas em relação às pesquisas desenvolvidas no tocante à biotecnologia da reprodução em machos do gênero Saimiri.(AU)

Some species of Saimiri primates are classified as vulnerable or near threatened with extinction. Facingthis reality, it is necessary to apply alternatives for the ex situ conservation (in captivity) of these primates,especially the development of biotechniques of reproduction. In this way, the present study aimed to compileinformation, in general terms, regarding the challenges, advances and perspectives in relation to the researchesdeveloped regarding the biotechnology of reproduction in males of the genus Saimiri.(AU)