Transferência Nuclear de Células Somáticas interespecífica (TNCSi) na conservação de cervídeos em risco de extinção / Interspecific Somatic Cell Nuclear Transfer (TNCSi) in the conservation of endangered species of deer

A Transferência Nuclear de Células Somáticas interespecífica (TNCSi) envolve a transferência de um núcleo ou célula de uma espécie para o citoplasma de um oócito enucleado de outra espécie. Após ativação, os complexos carioplasto-citoplasto reconstruídos podem ser cultivados in vitro até o blastocisto, o estádio final de desenvolvimento pré-implantação. Esta pode ser uma estratégia interessante na tentativa de conservação de espécies em risco de extinção. Esta revisão tem por objetivo apresentar alguns detalhes da técnica e relatar a experiência de nosso grupo usando como modelo o veado-catingueiro.(AU)

Interspecies Somatic Cell Nuclear Transfer (iSCNT) involves the transfer of a nucleus or cell from one species into the cytoplasm of an enucleated oocyte from another. Once activated, reconstructed caryoplast-cytoplast complexes can be cultured in vitro to blastocyst, the final stage of preimplantation development. This may be an interesting strategy in attempting to conserve endangered species. The objective of this review is to present some details of the technique and to report the experience of our group using as model the brown brocket deer.(AU)

Transferência Nuclear de Células Somáticas interespecífica (TNCSi) na conservação de cervídeos em risco de extinção / Interspecific Somatic Cell Nuclear Transfer (TNCSi) in the conservation of endangered species of deer

A Transferência Nuclear de Células Somáticas interespecífica (TNCSi) envolve a transferência de um núcleo ou célula de uma espécie para o citoplasma de um oócito enucleado de outra espécie. Após ativação, os complexos carioplasto-citoplasto reconstruídos podem ser cultivados in vitro até o blastocisto, o estádio final de desenvolvimento pré-implantação. Esta pode ser uma estratégia interessante na tentativa de conservação de espécies em risco de extinção. Esta revisão tem por objetivo apresentar alguns detalhes da técnica e relatar a experiência de nosso grupo usando como modelo o veado-catingueiro.

Interspecies Somatic Cell Nuclear Transfer (iSCNT) involves the transfer of a nucleus or cell from one species into the cytoplasm of an enucleated oocyte from another. Once activated, reconstructed caryoplast-cytoplast complexes can be cultured in vitro to blastocyst, the final stage of preimplantation development. This may be an interesting strategy in attempting to conserve endangered species. The objective of this review is to present some details of the technique and to report the experience of our group using as model the brown brocket deer.

Premissas e promessas da clonagem interespecífica de espécies em risco de extinção / Premises and promises of interspecific cloning in endangered species

Nos últimos anos, a transferência nuclear de células somáticas interespecífica (TNCSi) tem recebidodestaque devido à possibilidade de resgatar material genético de animais extintos e de auxiliar na multiplicaçãode espécies em vias de extinção. No entanto, apesar dos avanços obtidos até o momento, a TNCSi aindaapresenta baixa eficiência por possuir, por exemplo, altas taxas de perdas embrionárias e mortalidade após onascimento. Esses eventos estão relacionados com uma reprogramação anormal, que inclui a capacidade dooócito de modificar o estado de uma célula somática diferenciada para um estado de pluripotência. Assim, estarevisão tem por objetivo descrever o uso dessa biotécnica em diferentes espécies, relatar aspectos molecularesque comprometem o sucesso do desenvolvimento embrionário, bem como mostrar sua importância na medicina por meio da clonagem terapêutica.(AU)

In last years, the interspecific Somatic Cell Nuclear Transfer (iSCNT) has been highlighted due to thepossibility of recovering genetic material of extinct animals and aid to multiplied endangered species. However,despite the progress achieved to date, the iSCNT still has low efficiency by having, for example, high rates toboth embryonic loss and mortality after birth. These events are related to an abnormal reprogramming, whichincludes the oocyte's ability to modify the state of a differentiated somatic cell to a state of pluripotency. So thisreview is to describe the use of this biotechnical in different species, reporting molecular aspects thatcompromise the success of embryonic development as well as show their importance in medicine by therapeuticcloning(AU)

Premissas e promessas da clonagem interespecífica de espécies em risco de extinção / Premises and promises of interspecific cloning in endangered species

Nos últimos anos, a transferência nuclear de células somáticas interespecífica (TNCSi) tem recebidodestaque devido à possibilidade de resgatar material genético de animais extintos e de auxiliar na multiplicaçãode espécies em vias de extinção. No entanto, apesar dos avanços obtidos até o momento, a TNCSi aindaapresenta baixa eficiência por possuir, por exemplo, altas taxas de perdas embrionárias e mortalidade após onascimento. Esses eventos estão relacionados com uma reprogramação anormal, que inclui a capacidade dooócito de modificar o estado de uma célula somática diferenciada para um estado de pluripotência. Assim, estarevisão tem por objetivo descrever o uso dessa biotécnica em diferentes espécies, relatar aspectos molecularesque comprometem o sucesso do desenvolvimento embrionário, bem como mostrar sua importância na medicina por meio da clonagem terapêutica.

In last years, the interspecific Somatic Cell Nuclear Transfer (iSCNT) has been highlighted due to thepossibility of recovering genetic material of extinct animals and aid to multiplied endangered species. However,despite the progress achieved to date, the iSCNT still has low efficiency by having, for example, high rates toboth embryonic loss and mortality after birth. These events are related to an abnormal reprogramming, whichincludes the oocyte's ability to modify the state of a differentiated somatic cell to a state of pluripotency. So thisreview is to describe the use of this biotechnical in different species, reporting molecular aspects thatcompromise the success of embryonic development as well as show their importance in medicine by therapeuticcloning

Reproductive parameters and the use of MOET in transgenic founder goat carrying the human granulocyte colony-stimulating factor (hG-CSF) gene

This study aimed to monitor estrous cycle parameters of a human granulocyte colony-stimulating factor (hG-CSF)-transgenic founder female goat and to perform superovulation and embryo recovery (surgical or transcervical method) for further transfer to recipients to quickly obtain offspring. Two experiments were performed using a transgenic (TF) and a non-transgenic (NTF) female. In experiment 1, three estrous cycles were monitored for the following parameters: estrus behavior, progesterone concentration and ovarian activity. In experiment 2, two superovulation/embryo recovery sessions were performed and the recovered embryos were transferred to previously prepared recipients. Data were compared by either t test or Fisher's exact test. The mean interval between natural estrus was 20.7 ± 0.6 and 19.7 ± 0.6 (P > 0.05) days for the TF and NTF, respectively. Progesterone concentrations and ovarian activity were normal and similar between goats. The ovulation rate was similar between TF and NTF (12.0 ± 1.4 vs. 18.0 ± 4.2 CL; P > 0.05). No significant differences in embryo recovery rate (P > 0.05) were observed between the surgical and transcervical methods for TF (69.2 vs. 72.7%) or NTF (100.0 vs. 86.7%). Sixteen embryos from the TF were transferred to recipients, and eight kids were born. Among these kids, the transgene was identified in three (two males and one female), resulting in a transgenesis rate of 37.5%. In summary, the TF is a true founder, since she proved fertility and capacity of transmitting the hG-CSF transgene to progeny, suggesting that the analyzed reproductive traits were not compromised by the presence of the transgene.

Reproductive parameters and the use of MOET in transgenic founder goat carrying the human granulocyte colony-stimulating factor (hG-CSF) gene

This study aimed to monitor estrous cycle parameters of a human granulocyte colony-stimulating factor (hG-CSF)-transgenic founder female goat and to perform superovulation and embryo recovery (surgical or transcervical method) for further transfer to recipients to quickly obtain offspring. Two experiments were performed using a transgenic (TF) and a non-transgenic (NTF) female. In experiment 1, three estrous cycles were monitored for the following parameters: estrus behavior, progesterone concentration and ovarian activity. In experiment 2, two superovulation/embryo recovery sessions were performed and the recovered embryos were transferred to previously prepared recipients. Data were compared by either t test or Fisher's exact test. The mean interval between natural estrus was 20.7 ± 0.6 and 19.7 ± 0.6 (P > 0.05) days for the TF and NTF, respectively. Progesterone concentrations and ovarian activity were normal and similar between goats. The ovulation rate was similar between TF and NTF (12.0 ± 1.4 vs. 18.0 ± 4.2 CL; P > 0.05). No significant differences in embryo recovery rate (P > 0.05) were observed between the surgical and transcervical methods for TF (69.2 vs. 72.7%) or NTF (100.0 vs. 86.7%). Sixteen embryos from the TF were transferred to recipients, and eight kids were born. Among these kids, the transgene was identified in three (two males and one female), resulting in a transgenesis rate of 37.5%. In summary, the TF is a true founder, since she proved fertility and capacity of transmitting the hG-CSF transgene to progeny, suggesting that the analyzed reproductive traits were not compromised by the presence of the transgene.(AU)

Mensurações ultrassonográficas da cisterna da glândula mamária de caprino transgênico / Ultrasound measurements of the mammary gland of transgenic hormone-induced lactating goat

Milk production of transgenic does was evaluated by ultrasound measurements of the mammary gland. Two Canindé goats, which were nine months of age were used in the trial, one non-transgenic or other transgenic for hG-CSF. For hormone-induced lactation, animals were given estradiol (0.25mg/kg, IM), progesterone (0.75mg/kg, IM), and prednisolone (0.4mg/kg, IM). Ultrasonographic exams were carried out during milking, using a Falcon 100 ultrasound equipment with a 5MHz convex probe and were performed by the same operator. The results were expressed as mean±standard error. The maximum greater length and shorter length of the cistern were respectively 5.14cm and 1.36cm for the transgenic animal and 7.28cm and 2.25cm for non-transgenic, which is consistent with the maximum milk volume produced. The relationship between the average area of cisterns and milk yield was expressed as a linear correlation curve, with a correlation coefficient significantly positive for both transgenic (Y=-1.1314+10.8538*x; r=0.97) and non-transgenic (Y=-21.7551+18.3634*x; r=0.97) animals. In conclusion, the ultrasound is a practice and appropriate technique to evaluate the cisterns in ruminant udders in transgenic animal.(AU)