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1.
Anim. Reprod. (Online) ; 20(1): e20230017, 2023. graf, ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1427272

Resumo

The puma population is constantly decreasing, and cloning by somatic cell nuclear transfer can be used to conserve the species. One of the factors determining the success of the development of cloned embryos is the cell cycle stage of the donor cells. We evaluated the effects of full confluency (~100%), serum starvation (0.5% serum), and roscovitine (15 µM) treatments on the cell cycle synchronization in G0/G1 of puma skin-derived fibroblasts by flow cytometric analysis. Also, we assessed the effects of these synchronization methods on morphology, viability, and apoptosis levels using microscopy tools. The results showed that culturing the cells to confluence for 24 h (84.0%), 48 h (84.6%), and 72 h (84.2%) and serum starvation for 96 h (85.4%) yielded a significantly higher percentage of cells arrested in the G0/G1 (P < 0.05) phase than cells not subjected to any cell cycle synchronization method (73.9%). Nevertheless, while serum starvation reduced the percentage of viable cells, no difference was observed for the full confluence and roscovitine treatments (P > 0.05). Moreover, roscovitine for 12 h (78.6%) and 24 h (82.1%) was unable to synchronize cells in G0/G1 (P > 0.05). In summary, full confluency induces puma fibroblast cell cycle synchronization at the G0/G1 stage without affecting cell viability. These outcomes may be valuable for planning donor cells for somatic cell nuclear transfer in pumas.(AU)


Assuntos
Animais , Feminino , Panthera/genética , Fibroblastos/fisiologia , Pele , Sincronização do Estro/genética , Técnicas de Transferência Nuclear/veterinária , Roscovitina/efeitos adversos
2.
Rev. bras. reprod. anim ; 45(4): 179-183, out.-dez. 2021. ilus, graf
Artigo em Português | VETINDEX | ID: biblio-1492657

Resumo

Ovinos e caprinos são espécies que devido ao seu tamanho adequado, curto período gestacional e produção leiteira, tornaram-se importantes modelos na pesquisa pecuária, farmacêutica e biomédica. Assim, a engenharia genética tem sido amplamente aplicada à pesquisa com pequenos ruminantes. Caprinos e ovinos modificados geneticamente fornecem modelos valiosos para pesquisa sobre as funções dos genes, melhorando a exploração, obtendo produtos farmacêuticos no leite e aumentando a resistência às doenças. Além disso, o uso conjunto da clonagem e transgênese já foi responsável por marcos importantes na biotecnologia animal. Esta revisão destaca os avanços da clonagem e da engenharia genética nessas espécies obtidos nas últimas quatro décadas, com ênfase nas pesquisas realizadas no Brasil.


Sheep and goats are valuable species that due to their suitable size, short pregnancy period, and secretion of milk, have become important model in agricultural, pharmaceutical, and biomedical research. Thus, genome engineering has been widely applied to sheep and goat research. Gene-edited sheep and goats provide valuable models for investigations on gene functions, improving animal breeding, producing pharmaceuticals in milk and improving disease resistance. Additionally, the joint use of cloning and transgenesis has already been responsible for major milestones in animal biotechnology. This review highlights the advances of cloning and genome engineering in these species over the past four decades with particular emphasis on research in Brazil.


Assuntos
Animais , Clonagem de Organismos , Ovinos , Ruminantes , Transporte Ativo do Núcleo Celular
3.
R. bras. Reprod. Anim. ; 44(4): 121-128, out.-dez. 2020. tab
Artigo em Português | VETINDEX | ID: vti-763420

Resumo

Linhagens celulares, principalmente fibroblastos derivados da pele, podem ser ferramentas interessantes para a conservação e multiplicação de felídeos silvestres ameaçados de extinção. Esses animais em virtude de seu quantitativo reduzido têm nos bancos de células somáticas uma alternativa para a conservação de material biológico derivado de pequenas populações, garantindo assim o armazenamento da diversidade genética de diferentes grupos de indivíduos. Isso porque tais linhagens, quando apropriadamente estabelecidas por meio das técnicas de cultivo in vitro e criopreservação, permitem seu emprego na obtenção de embriões por clonagem por transferência nuclear de célula somática e produção de células induzidas à pluripotência. Assim, uma das etapas essenciais para o uso dessas linhagens de maneira eficiente consiste na avaliação dos efeitos das condições de cultivo in vitro e criopreservação das células, visando reconhecer os danos gerados pelas manipulações e identificar os ajustes necessários aos protocolos empregados. Portanto, o objetivo desta revisão consiste em reunir e explorar informações úteis sobre as condições de cultivo in vitro e criopreservação de células derivadas de felídeos silvestres, visando o estabelecimento de linhagens celulares na conservação e multiplicação destas espécies.(AU)


Cell lines, mainly fibroblasts derived from the skin, can be interesting tools for the conservation and multiplication of endangered wild felids. These animals, due to their reduced quantity, have somatic cell banks as an alternative for the conservation of biological material derived from small populations, thus guaranteeing the storage of the genetic diversity of different groups of individuals. This is because such lines, when properly established through in vitro culture and cryopreservation techniques, allow their use in obtaining embryos by cloning by somatic cell nuclear transfer and production of cells induced to pluripotency. Thus, one of the essential steps for the use of these lines in an efficient way consists of the evaluation of the effects of the conditions of in vitro culture and cryopreservation of the cells, aiming to recognize the damages generated by the manipulations and to identify the necessary adjustments to the employed protocols. Therefore, the aim of this review is to gather and explore useful information about in vitro culture and cryopreservation conditions of cells derived from wild felids, aiming at the establishment of cell lines in the conservation and multiplication of these species.(AU)


Assuntos
Animais , Animais Selvagens/embriologia , Animais Selvagens/genética , Linhagem Celular/classificação , Felidae/embriologia , Criopreservação , Fibroblastos
4.
Rev. bras. reprod. anim ; 44(4): 121-128, out.-dez. 2020. tab
Artigo em Português | VETINDEX | ID: biblio-1492626

Resumo

Linhagens celulares, principalmente fibroblastos derivados da pele, podem ser ferramentas interessantes para a conservação e multiplicação de felídeos silvestres ameaçados de extinção. Esses animais em virtude de seu quantitativo reduzido têm nos bancos de células somáticas uma alternativa para a conservação de material biológico derivado de pequenas populações, garantindo assim o armazenamento da diversidade genética de diferentes grupos de indivíduos. Isso porque tais linhagens, quando apropriadamente estabelecidas por meio das técnicas de cultivo in vitro e criopreservação, permitem seu emprego na obtenção de embriões por clonagem por transferência nuclear de célula somática e produção de células induzidas à pluripotência. Assim, uma das etapas essenciais para o uso dessas linhagens de maneira eficiente consiste na avaliação dos efeitos das condições de cultivo in vitro e criopreservação das células, visando reconhecer os danos gerados pelas manipulações e identificar os ajustes necessários aos protocolos empregados. Portanto, o objetivo desta revisão consiste em reunir e explorar informações úteis sobre as condições de cultivo in vitro e criopreservação de células derivadas de felídeos silvestres, visando o estabelecimento de linhagens celulares na conservação e multiplicação destas espécies.


Cell lines, mainly fibroblasts derived from the skin, can be interesting tools for the conservation and multiplication of endangered wild felids. These animals, due to their reduced quantity, have somatic cell banks as an alternative for the conservation of biological material derived from small populations, thus guaranteeing the storage of the genetic diversity of different groups of individuals. This is because such lines, when properly established through in vitro culture and cryopreservation techniques, allow their use in obtaining embryos by cloning by somatic cell nuclear transfer and production of cells induced to pluripotency. Thus, one of the essential steps for the use of these lines in an efficient way consists of the evaluation of the effects of the conditions of in vitro culture and cryopreservation of the cells, aiming to recognize the damages generated by the manipulations and to identify the necessary adjustments to the employed protocols. Therefore, the aim of this review is to gather and explore useful information about in vitro culture and cryopreservation conditions of cells derived from wild felids, aiming at the establishment of cell lines in the conservation and multiplication of these species.


Assuntos
Animais , Animais Selvagens/embriologia , Animais Selvagens/genética , Criopreservação , Felidae/embriologia , Linhagem Celular/classificação , Fibroblastos
5.
R. bras. Reprod. Anim. ; 43(2): 242-247, abr.-jun. 2019. tab
Artigo em Português | VETINDEX | ID: vti-21843

Resumo

A clonagem por transferência nuclear de células somáticas (TNCS) desempenha um importante papel na conservação e na multiplicação de mamíferos silvestres, especialmente quando associada à TNCS interespecífica. Contudo, a clonagem ainda possui uma baixa eficiência, sendo necessária uma extensa busca por elucidações mais precisas das metodologias empregadas em suas etapas de preparo do carioplastos (células doadoras de núcleo), obtenção dos citoplastos (oócitos receptores), e reconstrução embrionária. Assim, o objetivo desta revisão é abordar os aspectos relevantes das etapas da clonagem aplicadas a mamíferos silvestres, descrevendo seus resultados promissores e avanços alcançados.(AU)


Cloning by somatic cell nuclear transfer (SCNT) plays an important role in the conservation and multiplication of wild mammals, especially when associated with interspecific SCNT. Nevertheless, cloning still has a low efficiency, requiring an extensive search for more precise elucidations of the methodologies used in its stages of preparation of the karyoplasts (nucleus donor cells), production of cytoplasts (receptor oocytes), and embryonic reconstruction. Thus, the purpose of this review is to address the relevant aspects of the cloning steps applied to wild mammals, describing their promising results and advances.(AU)


Assuntos
Animais , Técnicas de Transferência Nuclear/veterinária , Clonagem de Organismos/veterinária , Animais Selvagens/embriologia
6.
Rev. bras. reprod. anim ; 43(2): 242-247, abr.-jun. 2019. tab
Artigo em Português | VETINDEX | ID: biblio-1492575

Resumo

A clonagem por transferência nuclear de células somáticas (TNCS) desempenha um importante papel na conservação e na multiplicação de mamíferos silvestres, especialmente quando associada à TNCS interespecífica. Contudo, a clonagem ainda possui uma baixa eficiência, sendo necessária uma extensa busca por elucidações mais precisas das metodologias empregadas em suas etapas de preparo do carioplastos (células doadoras de núcleo), obtenção dos citoplastos (oócitos receptores), e reconstrução embrionária. Assim, o objetivo desta revisão é abordar os aspectos relevantes das etapas da clonagem aplicadas a mamíferos silvestres, descrevendo seus resultados promissores e avanços alcançados.


Cloning by somatic cell nuclear transfer (SCNT) plays an important role in the conservation and multiplication of wild mammals, especially when associated with interspecific SCNT. Nevertheless, cloning still has a low efficiency, requiring an extensive search for more precise elucidations of the methodologies used in its stages of preparation of the karyoplasts (nucleus donor cells), production of cytoplasts (receptor oocytes), and embryonic reconstruction. Thus, the purpose of this review is to address the relevant aspects of the cloning steps applied to wild mammals, describing their promising results and advances.


Assuntos
Animais , Animais Selvagens/embriologia , Clonagem de Organismos/veterinária , Técnicas de Transferência Nuclear/veterinária
7.
Anim. Reprod. (Online) ; 14(1): 102-123, Jan.-Mar. 2017. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461258

Resumo

Since the beginning of modern embryology, scientists have wondered about how a small number of totipotent embryonic cells can become an individual with a wide variety of organs and tissues with distinct functions. Also, the idea of generating a cloned animal using a nucleus from a donor cell is not recent. However, it has taken years of research to achieve this goal, especially regarding mechanisms of cell reprogramming required to return a differentiated cell to totipotency. Cloning by somatic cell nuclear transfer (SCNT) has been a valuable tool to understand epigenetic mechanisms related to cellular reprogramming. However, cloning efficiency is still low, with a low percentage of embryos resulting in healthy animals. The high attrition rate is associated with incomplete or abnormal epigenetic reprogramming, such that many cloned embryos have DNA methylation patterns different than controls, resulting in faulty gene expression and subsequent developmental failures. Attempts to improve genome reprogramming by modulation of oocyte quality and/or somatic cell plasticity, thereby increasing cloning efficiency and preventing detrimental effects on development, have proven ineffective. The recent development of DNA editing techniques may facilitate an improved understanding of cellular reprogramming and the role of DNA methylation in development. These novel tools may lead to new means to modulate epigenetic programming and inheritance, and hold great promise to assist in epigenetic remodeling of the donor nucleus. Such strategies are likely to improve the odds for successful cloning.


Assuntos
Animais , Clonagem de Organismos/história , Clonagem de Organismos/tendências , Clonagem de Organismos/veterinária , Epigênese Genética/genética
8.
Anim. Reprod. (Online) ; 14(2): 377-382, Apr.-June.2017. ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1461271

Resumo

Twenty Years passed by since the production of Dolly the sheep, but despite significant technical progress has been achieved in the manipulation procedures, the proportion of offspring following transfer of SCNT embryos has remained almost unchanged in farm animals. Remarkable progress has been obtained instead in laboratory animals, particularly by Japanese Groups, in the mouse. However, the nuclear reprogramming strategies tested in mouse do not always work in farm animals, and others are difficult to be implemented, for require complicated molecular biology tools unavailable yet in large animals. In this review we put in contest the previous work done in farm and laboratory animals with recent achievements obtained in our laboratory, and we also indicate a road map to increase the reliability of SCNT procedures.


Assuntos
Animais , Reprogramação Celular/genética , Transferência Embrionária , Transferência Embrionária/tendências , Células-Tronco Adultas
9.
Anim. Reprod. (Online) ; 14(4): 1110-1123, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1461307

Resumo

The birth of cloned goats has been well documented, but the overall goat cloning efficiency by somatic cell nuclear transfer procedures is still low, which may be further intensified in extreme environments. The aim of this study was to produce cloned goats under the conditions of the Brazilian Semi Arid region, in a transgenic program for the expression of human lysozyme in the milk to target childhood diarrhea and malnutrition, comparing the effects of oocyte source, cell type, and embryo reconstruction procedures on in vitro and in vivo embryo survival after cloning by micromanipulation or by handmade cloning. The use of in vitro-matured oocytes resulted in more viable embryos after cloning than in vivo-matured cytoplasts, but no differences in pregnancy rates on day 23 were seen between oocyte sources (77.5 vs. 77.8%, respectively). The presence or absence of the zona pellucida for embryo reconstruction (78.8 vs. 76.0%, respectively) did not affect pregnancy outcome after transfer. However, pregnancy rate on day 23 was higher for embryos chemically activated by a conventional than a modified protocol (88.1 vs. 50.0%), and for embryos reconstructed with mesenchymal stem cells and fetal fibroblasts (100.0 and 93.3%) than with adult fibroblasts (64.7%). Although most pregnancies were lost, the birth of a cloned female was obtained from embryos reconstructed by micromanipulation using non-transgenic control cells and in vitro-matured oocytes with intact zona pellucida, after conventional activation and transfer at the 1-cell stage.


Assuntos
Animais , Cabras/embriologia , Clonagem de Organismos , Clonagem de Organismos/tendências , Técnicas de Maturação in Vitro de Oócitos/veterinária
10.
Anim. Reprod. ; 14(4): 1110-1123, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-18090

Resumo

The birth of cloned goats has been well documented, but the overall goat cloning efficiency by somatic cell nuclear transfer procedures is still low, which may be further intensified in extreme environments. The aim of this study was to produce cloned goats under the conditions of the Brazilian Semi Arid region, in a transgenic program for the expression of human lysozyme in the milk to target childhood diarrhea and malnutrition, comparing the effects of oocyte source, cell type, and embryo reconstruction procedures on in vitro and in vivo embryo survival after cloning by micromanipulation or by handmade cloning. The use of in vitro-matured oocytes resulted in more viable embryos after cloning than in vivo-matured cytoplasts, but no differences in pregnancy rates on day 23 were seen between oocyte sources (77.5 vs. 77.8%, respectively). The presence or absence of the zona pellucida for embryo reconstruction (78.8 vs. 76.0%, respectively) did not affect pregnancy outcome after transfer. However, pregnancy rate on day 23 was higher for embryos chemically activated by a conventional than a modified protocol (88.1 vs. 50.0%), and for embryos reconstructed with mesenchymal stem cells and fetal fibroblasts (100.0 and 93.3%) than with adult fibroblasts (64.7%). Although most pregnancies were lost, the birth of a cloned female was obtained from embryos reconstructed by micromanipulation using non-transgenic control cells and in vitro-matured oocytes with intact zona pellucida, after conventional activation and transfer at the 1-cell stage.(AU)


Assuntos
Animais , Cabras/embriologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Clonagem de Organismos/tendências , Clonagem de Organismos
11.
Anim. Reprod. ; 14(1): 102-123, Jan.-Mar. 2017. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-16011

Resumo

Since the beginning of modern embryology, scientists have wondered about how a small number of totipotent embryonic cells can become an individual with a wide variety of organs and tissues with distinct functions. Also, the idea of generating a cloned animal using a nucleus from a donor cell is not recent. However, it has taken years of research to achieve this goal, especially regarding mechanisms of cell reprogramming required to return a differentiated cell to totipotency. Cloning by somatic cell nuclear transfer (SCNT) has been a valuable tool to understand epigenetic mechanisms related to cellular reprogramming. However, cloning efficiency is still low, with a low percentage of embryos resulting in healthy animals. The high attrition rate is associated with incomplete or abnormal epigenetic reprogramming, such that many cloned embryos have DNA methylation patterns different than controls, resulting in faulty gene expression and subsequent developmental failures. Attempts to improve genome reprogramming by modulation of oocyte quality and/or somatic cell plasticity, thereby increasing cloning efficiency and preventing detrimental effects on development, have proven ineffective. The recent development of DNA editing techniques may facilitate an improved understanding of cellular reprogramming and the role of DNA methylation in development. These novel tools may lead to new means to modulate epigenetic programming and inheritance, and hold great promise to assist in epigenetic remodeling of the donor nucleus. Such strategies are likely to improve the odds for successful cloning.(AU)


Assuntos
Animais , Epigênese Genética/genética , Clonagem de Organismos/história , Clonagem de Organismos/tendências , Clonagem de Organismos/veterinária
12.
Anim. Reprod. ; 14(2): 377-382, Apr.-June.2017. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-15899

Resumo

Twenty Years passed by since the production of Dolly the sheep, but despite significant technical progress has been achieved in the manipulation procedures, the proportion of offspring following transfer of SCNT embryos has remained almost unchanged in farm animals. Remarkable progress has been obtained instead in laboratory animals, particularly by Japanese Groups, in the mouse. However, the nuclear reprogramming strategies tested in mouse do not always work in farm animals, and others are difficult to be implemented, for require complicated molecular biology tools unavailable yet in large animals. In this review we put in contest the previous work done in farm and laboratory animals with recent achievements obtained in our laboratory, and we also indicate a road map to increase the reliability of SCNT procedures.(AU)


Assuntos
Animais , Reprogramação Celular/genética , Transferência Embrionária/tendências , Transferência Embrionária , Células-Tronco Adultas
13.
R. bras. Reprod. Anim. ; 40(4): 154-157, Out-Dez. 2016. ilus
Artigo em Português | VETINDEX | ID: vti-24014

Resumo

Transgenic animals are those animals which are genetically modified. A foreign gene is inserted intothese animals to see certain characteristics. These animals can be helpful in producing organs, growthhormones and useful proteins for the humans. Transgenic farm animals were first developed in 1985 and wereuseful in the production of biopharmaceuticals shortly thereafter. The ideal transgenic animal produces plentyof milk, and has relatively short generation times. Thus, small ruminants have been selected for a number ofreasons, the chief of which is the short generational time of 18 months. Thus, this review aims to present thecharacteristics and main applications of transgenesis and cloning in small ruminants.(AU)


Assuntos
Animais , Clonagem de Organismos/veterinária , Ruminantes/embriologia , Células-Tronco Adultas
14.
Rev. bras. reprod. anim ; 40(4): 154-157, Out-Dez. 2016. ilus
Artigo em Português | VETINDEX | ID: biblio-1492227

Resumo

Transgenic animals are those animals which are genetically modified. A foreign gene is inserted intothese animals to see certain characteristics. These animals can be helpful in producing organs, growthhormones and useful proteins for the humans. Transgenic farm animals were first developed in 1985 and wereuseful in the production of biopharmaceuticals shortly thereafter. The ideal transgenic animal produces plentyof milk, and has relatively short generation times. Thus, small ruminants have been selected for a number ofreasons, the chief of which is the short generational time of 18 months. Thus, this review aims to present thecharacteristics and main applications of transgenesis and cloning in small ruminants.


Assuntos
Animais , Clonagem de Organismos/veterinária , Ruminantes/embriologia , Células-Tronco Adultas
15.
Anim. Reprod. ; 12(3): 389-396, July.-Sept.2015. ilus
Artigo em Inglês | VETINDEX | ID: vti-26228

Resumo

This paper provides basic concepts of genomic selection (GS) methods in beef and dairy cattle production in combination with assisted reproductive technologies (ART) such as ovum-pick up and in vitroproduction (OPU-IVP). We first introduce genomic tools and discuss main methods of GS as practiced to-date. The general benefit from GS is that it enables selecting animals accurately early in life using genomic predictions particularly those phenotypes that are very difficult or expensive to measure. While it is known that GS increases genetic gain and profit in conventional cattle breeding, GS is much more desirable when combined with OPU-IVP in cattle production. The expected benefits of GS-OPU-IVP far exceed the benefits achieved by either GS or OPU-IVP alone mainly due to tremendous reduction in generation interval. The genetic improvement will increase even further, if genetic merit of donor cows and bulls used in OPU-IVP for key economic traits are maximal. The paper also highlights some challenges particularly with regard to embryo biopsies and quantity and quality of embryo DNA for whole genome genotyping and ways to overcome difficulties. We briefly discuss the somatic cell nuclear transfer (SCNT) technique in the context of applying GS on fibroblast cell lines from fetuses obtained from OPU-IVP techniques and provide our perspectives on how it might pave way for even more rapid cattle improvement. Main conclusion is that employing genomic selection in ARTs such as OPU-IVP of embryos coupled with embryo sexing and SCNT will lead to rapid dissemination of high genetic merit animals on a scale never been seen before. Finally, the paper outlines current research activities on combined genomic selection and advanced reproductive technologies in the GIFT project consortium (www.gift.ku.dk). (AU)


Assuntos
Animais , Bovinos , Melhoramento Genético , Criação de Animais Domésticos , Genômica/classificação , Transferência Embrionária/veterinária
16.
Anim. Reprod. (Online) ; 12(3): 389-396, July.-Sept.2015. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461166

Resumo

This paper provides basic concepts of genomic selection (GS) methods in beef and dairy cattle production in combination with assisted reproductive technologies (ART) such as ovum-pick up and in vitroproduction (OPU-IVP). We first introduce genomic tools and discuss main methods of GS as practiced to-date. The general benefit from GS is that it enables selecting animals accurately early in life using genomic predictions particularly those phenotypes that are very difficult or expensive to measure. While it is known that GS increases genetic gain and profit in conventional cattle breeding, GS is much more desirable when combined with OPU-IVP in cattle production. The expected benefits of GS-OPU-IVP far exceed the benefits achieved by either GS or OPU-IVP alone mainly due to tremendous reduction in generation interval. The genetic improvement will increase even further, if genetic merit of donor cows and bulls used in OPU-IVP for key economic traits are maximal. The paper also highlights some challenges particularly with regard to embryo biopsies and quantity and quality of embryo DNA for whole genome genotyping and ways to overcome difficulties. We briefly discuss the somatic cell nuclear transfer (SCNT) technique in the context of applying GS on fibroblast cell lines from fetuses obtained from OPU-IVP techniques and provide our perspectives on how it might pave way for even more rapid cattle improvement. Main conclusion is that employing genomic selection in ARTs such as OPU-IVP of embryos coupled with embryo sexing and SCNT will lead to rapid dissemination of high genetic merit animals on a scale never been seen before. Finally, the paper outlines current research activities on combined genomic selection and advanced reproductive technologies in the GIFT project consortium (www.gift.ku.dk).


Assuntos
Animais , Bovinos , Criação de Animais Domésticos , Genômica/classificação , Melhoramento Genético , Transferência Embrionária/veterinária
17.
Ci. Rural ; 45(10): 1879-1886, Oct. 2015.
Artigo em Inglês | VETINDEX | ID: vti-28889

Resumo

This review aim to present some clinical problems found in IVP-derived animals focusing on NT procedures and to discuss the possible role of epigenetics in such process. Also, as cell-secreted vesicles have been reported as possible regulators of important physiological reproductive processes such as folliculogenesis and fertilization, it is also presented herein a new perspective of manipulating the pre-implantation period trough effector molecules contained in such vesicles.(AU)


Nesta revisão, apresentamos alguns problemas clínicos encontrados nos animais derivados de PIV, principalmente derivados de transferência de núcleo, e discutimos o possível papel da epigenética em tais processos. Além disso, uma vez que vesículas secretadas por células têm sido descritas como possíveis reguladores de processos reprodutivos fisiológicos importantes, tais como a foliculogênese e a fertilização, estas são aqui apresentadas como uma possível nova ferramenta para a manipulação do período embrionário pré-implantacional através de moléculas efetoras, contidas em tais vesículas.(AU)


Assuntos
Animais , Bovinos , Reprodução , Fertilização in vitro/veterinária , Embrião de Mamíferos , Desenvolvimento Embrionário , Epigenômica
18.
R. bras. Reprod. Anim. ; 38(1): 43-48, Jan.-Mar. 2014. tab
Artigo em Português | VETINDEX | ID: vti-29098

Resumo

As biotécnicas reprodutivas têm sido cada vez mais utilizadas como ferramentas alternativas emprogramas de conservação do material genético de espécies ameaçadas de extinção. O presente artigo delineia osavanços já ocorridos na reprodução de animais carnívoros, com ênfase na clonagem, não somente para apreservação das espécies em vias de extinção, como também para sua aplicação com fins terapêuticos. Aclonagem animal representa um dos maiores avanços dentro da medicina veterinária, mas ainda apresentagrandes entraves para a consolidação da sua eficácia, necessitando de mais investimentos científicos na área.(AU)


The reproductive biotechnologies have been increasingly used as alternative tools in conservationprograms of genetic material from endangered species. This article outlines the progress that has alreadyoccurred in the reproduction of carnivorous animals, with emphasis on cloning, not only for the preservation ofendangered species, but also regarding its application for therapeutic purposes. Animal cloning is one of thebiggest advances in veterinary medicine, but still has major obstacles for the consolidation of its effectiveness,requiring more investment in the scientific area.(AU)


Assuntos
Animais , Animais Selvagens/embriologia , Animais Selvagens/genética , Clonagem de Organismos/tendências , Clonagem de Organismos/veterinária , Biotecnologia
19.
Rev. bras. reprod. anim ; 38(1): 43-48, Jan.-Mar. 2014. tab
Artigo em Português | VETINDEX | ID: biblio-1492097

Resumo

As biotécnicas reprodutivas têm sido cada vez mais utilizadas como ferramentas alternativas emprogramas de conservação do material genético de espécies ameaçadas de extinção. O presente artigo delineia osavanços já ocorridos na reprodução de animais carnívoros, com ênfase na clonagem, não somente para apreservação das espécies em vias de extinção, como também para sua aplicação com fins terapêuticos. Aclonagem animal representa um dos maiores avanços dentro da medicina veterinária, mas ainda apresentagrandes entraves para a consolidação da sua eficácia, necessitando de mais investimentos científicos na área.


The reproductive biotechnologies have been increasingly used as alternative tools in conservationprograms of genetic material from endangered species. This article outlines the progress that has alreadyoccurred in the reproduction of carnivorous animals, with emphasis on cloning, not only for the preservation ofendangered species, but also regarding its application for therapeutic purposes. Animal cloning is one of thebiggest advances in veterinary medicine, but still has major obstacles for the consolidation of its effectiveness,requiring more investment in the scientific area.


Assuntos
Animais , Animais Selvagens/embriologia , Animais Selvagens/genética , Clonagem de Organismos/tendências , Clonagem de Organismos/veterinária , Biotecnologia
20.
Anim. Reprod. (Online) ; 10(3): 334-343, 2013. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1461080

Resumo

Assisted reproductive techniques in the horse have been only recently become available compared to other domestic species, in particular ruminants. The scarce availability of abattoir ovaries and t he lack of interest from horse breeders and breed associations, and the anatomical and physiological differences have been the main reasons for this delay. Progressively though, the technology of oocyte maturation in vitro has been established especially after the application of ICSI to obtain in vitro fertilization. The parallel improvement of oocyte maturation conditions and embryo culture media has increased the rates of embryo development from in vitro matured and in vitro cultured ICSI embryos from 5-10% in the early studies to up to 26% in the latest under experimental conditions with abattoir derived oocytes. In 2003, the birth of the first cloned foal established the technology of somatic cell nuclear transfer. The largest set of data on non-surgical embryo transfer of in vitro produced embryos, from ICSI of in vitro-matured Ovum Pick Up (OPU) oocytes, and from somatic cell nuclear transfer, has been obtained in our laboratory. In the clinical context, where OPU and ICSI are applied for the treatment of female and or male infertility, the yield of embryos has been lower compared to experimental conditions. In conclusion, the basic procedures have been established for the use of assisted reproduction and somatic cell nuclear transfer to a degree suitable for clinical applications and the results have been replicated in several laboratories around the world.


Assuntos
Animais , Infertilidade/metabolismo , Matadouros , Ovário/anatomia & histologia , Reprodução/fisiologia , Cavalos/classificação
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