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Marcos Antonio Lemos de Oliveira - One of the best experts on this subject based on the ideXlab platform.
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Conceptus loss in Santa Inês ewes carrying twin pregnancies by Natural Mating or embryo transfer
Theriogenology, 2018Co-Authors: José Carlos Ferreira-silva, Leopoldo Mayer Freitas Neto, Marcelo Tigre Moura, Fernando Tenório Filho, L. R. S. Oliveira, Cláudio Coutinho Bartolomeu, Marcos Antonio Lemos de OliveiraAbstract:Abstract Commercial application of reproductive biotechnologies such as multiple ovulation and embryo transfer depends on its overall efficiency. Sheep embryo transfer is gradually gaining wider adoption, but pregnancy rates after embryo transfer remain lower than those derived from Natural Mating for most breeds. The work was aimed to evaluate embryonic and fetal losses in Santa Ines ewes carrying twin pregnancies by Natural Mating or embryo transfer. Ewes were subjected to synchronized Natural Mating by ram effect or used as recipients for embryo transfer. Ewes diagnosed as carrying twin pregnancies at day 25 were used in the experiment (n = 42). Conceptus viability was monitored by ultrasonography on days 30, 35, 40, 45, 50, and 55 after conception. Conceptus loss was similar (P > 0.05) within Natural Mating 11/42 (26.19%) and embryo transfer 14/42 (33.34%). However, overall embryonic loss (80.0%) was greater (P
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ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer
Journal of Reproduction and Development, 2010Co-Authors: Leopoldo Mayer Freitas Neto, M H B Santos, Paulo Fernandes de Lima, C R Aguiar Filho, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Jose Monteiro Almeida Irmao, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P<0.05) in NM (42.21 ± 2.86 days) than in FrE (43.98 ± 3.00 days), FE (44.97 ± 1.83 days) and VE (44.58 ± 1.97days). Visualization of the scrotal bag, prepuce and vulva occurred, respectively, earlier (P<0.05) in NM (45.22 ± 1.25, 45.95 ± 1.53 and 45.01 ± 1.03 days) than in FrE (48.91 ± 1.92, 48.52 ± 1.41 and 47.41 ± 1.41 days), FE (49.97 ± 1.08, 49.18 ± 2.00 and 47.64 ± 1.82 days) and VE (50.12 ± 1.66, 49.27 ± 1.61 and 47.93 ± 1.92 days). The results show that fetal sexing can be accomplished from the 50th day onward in fetuses produced by Natural Mating and from the 55th day onward in fetuses derived from fresh, frozen and vitrified embryos. It can also be concluded that real-time ultrasonography is a reliable tool for fetal sex determination in sheep taking into account both the location of the genital tubercle and the identification of external genital structures.
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Ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer.
The Journal of reproduction and development, 2010Co-Authors: Leopoldo Mayer de Freitas Neto, Paulo Fernandes de Lima, Maico Henrique Barbosa dos Santos, Cristiano Rocha de Aguiar Filho, José Monteiro de Almeida Irmão, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P
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Reliability of ultrasound for early sexing of goat fetuses derived from Natural Mating and from fresh, frozen and vitrified embryo transfer.
Reproduction, fertility, and development, 2010Co-Authors: L M Freitas Neto, Paulo Fernandes de Lima, Maico Henrique Barbosa dos Santos, C R Aguiar Filho, E R Santos Junior, José Monteiro de Almeida Irmão, Eduardo Luiz Cavalcanti Caldas, Marcos Antonio Lemos de OliveiraAbstract:The aim of the present study was to identify the migration period of the genital tubercle and its later differentiation into external genital structures in fetuses derived from Natural Mating and fetuses from fresh, frozen and vitrified embryo transfer. A transrectal ultrasound with a double-frequency linear transducer (6.0 and 8.0 MHz) was used to monitor 123 goat fetuses, which were allocated to one of four groups: fetuses originating from controlled Natural Mating (G1, n = 32) and fetuses derived from fresh (G2, n = 34), frozen (G3, n = 30) and vitrified (G4, n = 27) embryo transfer. The transferable embryos were collected 7 days after Mating by laparoscopy. Migration of the genital tubercle occurred significantly earlier (P < 0.05) in G1 than in G2, G3 and G4. The visualisation of the scrotum, prepuce and vulva occurred significantly earlier (P < 0.05) in G1 than in G2, G3 and G4. Our results show that fetal sexing is feasible after 55 days for fetuses from Natural Mating and after 60 days in fetuses from fresh and cryopreserved embryos. Thus, real-time ultrasonography is a reliable tool for fetal sex determination in goats after Day 50 of pregnancy, taking into account both the location of the genital tubercle and the identification of external genital structures.
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Sexing of Dorper sheep fetuses derived from Natural Mating and embryo transfer by ultrasonography.
Reproduction, fertility, and development, 2007Co-Authors: M H B Santos, C I M Gonzalez, F Q G Bezerra, H-D Reichenbach, Paulo Fernandes de Lima, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:In order to improve fetal sexing in the Dorper sheep breed, the objective of the present study was to determine, by repeated ultrasonographic examinations, the migration period of the genital tubercle (GT) in sheep fetuses derived from Natural Mating or embryo transfer and to compare the accuracy of a single examination with repeated examinations at short intervals. For this purpose, transrectal ultrasound was performed, using a double-frequency linear transducer (6.0 and 8.0 MHz) for monitoring 51 sheep fetuses distributed in three experimental groups (EI, EII and EIII). The fetuses in EI (n = 23) and EII (n = 18) derived, respectively, from Natural Mating and embryo transfer were monitored at 48-h intervals from the 30th to 60th day of gestation and sexed based on the final location of the GT. The fetuses in EIII (n = 10), which originated from embryo transfer, were examined only once on the 65th day of gestation and sexed taking into consideration the final position of the GT and/or by identification of anatomical structures of external genitalia. The accuracy of fetal sexing was 91.3% (21 fetuses sexed/23 quantified) in EI, 88.9% (16 sexed/18 quantified) in EII and 100% (10 sexed/10 quantified) in EIII, without significant difference (P > 0.05) between experiments. Migration of the GT occurred earlier (P < 0.05) in fetuses produced by Natural Mating (43.0 +/- 2.8 days) than in those derived from embryo transfer (46.1 +/- 4.7 days). The results show that fetal sexing can be done from the 50th day onward in fetuses produced by Natural Mating and from the 60th day onward in fetuses derived from frozen embryos. It can also be concluded that repeated ultrasonographic exams in short time intervals do not maximise the accuracy of fetal sexing. In addition, real-time ultrasonography is a reliable tool for fetal sex determination in sheep after Day 50 of gestation, taking into account both the location of the GT and the identification of external genital structures.
Paulo Fernandes de Lima - One of the best experts on this subject based on the ideXlab platform.
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ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer
Journal of Reproduction and Development, 2010Co-Authors: Leopoldo Mayer Freitas Neto, M H B Santos, Paulo Fernandes de Lima, C R Aguiar Filho, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Jose Monteiro Almeida Irmao, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P<0.05) in NM (42.21 ± 2.86 days) than in FrE (43.98 ± 3.00 days), FE (44.97 ± 1.83 days) and VE (44.58 ± 1.97days). Visualization of the scrotal bag, prepuce and vulva occurred, respectively, earlier (P<0.05) in NM (45.22 ± 1.25, 45.95 ± 1.53 and 45.01 ± 1.03 days) than in FrE (48.91 ± 1.92, 48.52 ± 1.41 and 47.41 ± 1.41 days), FE (49.97 ± 1.08, 49.18 ± 2.00 and 47.64 ± 1.82 days) and VE (50.12 ± 1.66, 49.27 ± 1.61 and 47.93 ± 1.92 days). The results show that fetal sexing can be accomplished from the 50th day onward in fetuses produced by Natural Mating and from the 55th day onward in fetuses derived from fresh, frozen and vitrified embryos. It can also be concluded that real-time ultrasonography is a reliable tool for fetal sex determination in sheep taking into account both the location of the genital tubercle and the identification of external genital structures.
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Ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer.
The Journal of reproduction and development, 2010Co-Authors: Leopoldo Mayer de Freitas Neto, Paulo Fernandes de Lima, Maico Henrique Barbosa dos Santos, Cristiano Rocha de Aguiar Filho, José Monteiro de Almeida Irmão, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P
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Reliability of ultrasound for early sexing of goat fetuses derived from Natural Mating and from fresh, frozen and vitrified embryo transfer.
Reproduction, fertility, and development, 2010Co-Authors: L M Freitas Neto, Paulo Fernandes de Lima, Maico Henrique Barbosa dos Santos, C R Aguiar Filho, E R Santos Junior, José Monteiro de Almeida Irmão, Eduardo Luiz Cavalcanti Caldas, Marcos Antonio Lemos de OliveiraAbstract:The aim of the present study was to identify the migration period of the genital tubercle and its later differentiation into external genital structures in fetuses derived from Natural Mating and fetuses from fresh, frozen and vitrified embryo transfer. A transrectal ultrasound with a double-frequency linear transducer (6.0 and 8.0 MHz) was used to monitor 123 goat fetuses, which were allocated to one of four groups: fetuses originating from controlled Natural Mating (G1, n = 32) and fetuses derived from fresh (G2, n = 34), frozen (G3, n = 30) and vitrified (G4, n = 27) embryo transfer. The transferable embryos were collected 7 days after Mating by laparoscopy. Migration of the genital tubercle occurred significantly earlier (P < 0.05) in G1 than in G2, G3 and G4. The visualisation of the scrotum, prepuce and vulva occurred significantly earlier (P < 0.05) in G1 than in G2, G3 and G4. Our results show that fetal sexing is feasible after 55 days for fetuses from Natural Mating and after 60 days in fetuses from fresh and cryopreserved embryos. Thus, real-time ultrasonography is a reliable tool for fetal sex determination in goats after Day 50 of pregnancy, taking into account both the location of the genital tubercle and the identification of external genital structures.
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Sexing of Dorper sheep fetuses derived from Natural Mating and embryo transfer by ultrasonography.
Reproduction, fertility, and development, 2007Co-Authors: M H B Santos, C I M Gonzalez, F Q G Bezerra, H-D Reichenbach, Paulo Fernandes de Lima, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:In order to improve fetal sexing in the Dorper sheep breed, the objective of the present study was to determine, by repeated ultrasonographic examinations, the migration period of the genital tubercle (GT) in sheep fetuses derived from Natural Mating or embryo transfer and to compare the accuracy of a single examination with repeated examinations at short intervals. For this purpose, transrectal ultrasound was performed, using a double-frequency linear transducer (6.0 and 8.0 MHz) for monitoring 51 sheep fetuses distributed in three experimental groups (EI, EII and EIII). The fetuses in EI (n = 23) and EII (n = 18) derived, respectively, from Natural Mating and embryo transfer were monitored at 48-h intervals from the 30th to 60th day of gestation and sexed based on the final location of the GT. The fetuses in EIII (n = 10), which originated from embryo transfer, were examined only once on the 65th day of gestation and sexed taking into consideration the final position of the GT and/or by identification of anatomical structures of external genitalia. The accuracy of fetal sexing was 91.3% (21 fetuses sexed/23 quantified) in EI, 88.9% (16 sexed/18 quantified) in EII and 100% (10 sexed/10 quantified) in EIII, without significant difference (P > 0.05) between experiments. Migration of the GT occurred earlier (P < 0.05) in fetuses produced by Natural Mating (43.0 +/- 2.8 days) than in those derived from embryo transfer (46.1 +/- 4.7 days). The results show that fetal sexing can be done from the 50th day onward in fetuses produced by Natural Mating and from the 60th day onward in fetuses derived from frozen embryos. It can also be concluded that repeated ultrasonographic exams in short time intervals do not maximise the accuracy of fetal sexing. In addition, real-time ultrasonography is a reliable tool for fetal sex determination in sheep after Day 50 of gestation, taking into account both the location of the GT and the identification of external genital structures.
M H B Santos - One of the best experts on this subject based on the ideXlab platform.
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ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer
Journal of Reproduction and Development, 2010Co-Authors: Leopoldo Mayer Freitas Neto, M H B Santos, Paulo Fernandes de Lima, C R Aguiar Filho, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Jose Monteiro Almeida Irmao, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P<0.05) in NM (42.21 ± 2.86 days) than in FrE (43.98 ± 3.00 days), FE (44.97 ± 1.83 days) and VE (44.58 ± 1.97days). Visualization of the scrotal bag, prepuce and vulva occurred, respectively, earlier (P<0.05) in NM (45.22 ± 1.25, 45.95 ± 1.53 and 45.01 ± 1.03 days) than in FrE (48.91 ± 1.92, 48.52 ± 1.41 and 47.41 ± 1.41 days), FE (49.97 ± 1.08, 49.18 ± 2.00 and 47.64 ± 1.82 days) and VE (50.12 ± 1.66, 49.27 ± 1.61 and 47.93 ± 1.92 days). The results show that fetal sexing can be accomplished from the 50th day onward in fetuses produced by Natural Mating and from the 55th day onward in fetuses derived from fresh, frozen and vitrified embryos. It can also be concluded that real-time ultrasonography is a reliable tool for fetal sex determination in sheep taking into account both the location of the genital tubercle and the identification of external genital structures.
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Sexing of Dorper sheep fetuses derived from Natural Mating and embryo transfer by ultrasonography.
Reproduction, fertility, and development, 2007Co-Authors: M H B Santos, C I M Gonzalez, F Q G Bezerra, H-D Reichenbach, Paulo Fernandes de Lima, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:In order to improve fetal sexing in the Dorper sheep breed, the objective of the present study was to determine, by repeated ultrasonographic examinations, the migration period of the genital tubercle (GT) in sheep fetuses derived from Natural Mating or embryo transfer and to compare the accuracy of a single examination with repeated examinations at short intervals. For this purpose, transrectal ultrasound was performed, using a double-frequency linear transducer (6.0 and 8.0 MHz) for monitoring 51 sheep fetuses distributed in three experimental groups (EI, EII and EIII). The fetuses in EI (n = 23) and EII (n = 18) derived, respectively, from Natural Mating and embryo transfer were monitored at 48-h intervals from the 30th to 60th day of gestation and sexed based on the final location of the GT. The fetuses in EIII (n = 10), which originated from embryo transfer, were examined only once on the 65th day of gestation and sexed taking into consideration the final position of the GT and/or by identification of anatomical structures of external genitalia. The accuracy of fetal sexing was 91.3% (21 fetuses sexed/23 quantified) in EI, 88.9% (16 sexed/18 quantified) in EII and 100% (10 sexed/10 quantified) in EIII, without significant difference (P > 0.05) between experiments. Migration of the GT occurred earlier (P < 0.05) in fetuses produced by Natural Mating (43.0 +/- 2.8 days) than in those derived from embryo transfer (46.1 +/- 4.7 days). The results show that fetal sexing can be done from the 50th day onward in fetuses produced by Natural Mating and from the 60th day onward in fetuses derived from frozen embryos. It can also be concluded that repeated ultrasonographic exams in short time intervals do not maximise the accuracy of fetal sexing. In addition, real-time ultrasonography is a reliable tool for fetal sex determination in sheep after Day 50 of gestation, taking into account both the location of the GT and the identification of external genital structures.
Jairo Pereira Neves - One of the best experts on this subject based on the ideXlab platform.
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ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer
Journal of Reproduction and Development, 2010Co-Authors: Leopoldo Mayer Freitas Neto, M H B Santos, Paulo Fernandes de Lima, C R Aguiar Filho, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Jose Monteiro Almeida Irmao, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P<0.05) in NM (42.21 ± 2.86 days) than in FrE (43.98 ± 3.00 days), FE (44.97 ± 1.83 days) and VE (44.58 ± 1.97days). Visualization of the scrotal bag, prepuce and vulva occurred, respectively, earlier (P<0.05) in NM (45.22 ± 1.25, 45.95 ± 1.53 and 45.01 ± 1.03 days) than in FrE (48.91 ± 1.92, 48.52 ± 1.41 and 47.41 ± 1.41 days), FE (49.97 ± 1.08, 49.18 ± 2.00 and 47.64 ± 1.82 days) and VE (50.12 ± 1.66, 49.27 ± 1.61 and 47.93 ± 1.92 days). The results show that fetal sexing can be accomplished from the 50th day onward in fetuses produced by Natural Mating and from the 55th day onward in fetuses derived from fresh, frozen and vitrified embryos. It can also be concluded that real-time ultrasonography is a reliable tool for fetal sex determination in sheep taking into account both the location of the genital tubercle and the identification of external genital structures.
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Ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer.
The Journal of reproduction and development, 2010Co-Authors: Leopoldo Mayer de Freitas Neto, Paulo Fernandes de Lima, Maico Henrique Barbosa dos Santos, Cristiano Rocha de Aguiar Filho, José Monteiro de Almeida Irmão, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P
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Sexing of Dorper sheep fetuses derived from Natural Mating and embryo transfer by ultrasonography.
Reproduction, fertility, and development, 2007Co-Authors: M H B Santos, C I M Gonzalez, F Q G Bezerra, H-D Reichenbach, Paulo Fernandes de Lima, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:In order to improve fetal sexing in the Dorper sheep breed, the objective of the present study was to determine, by repeated ultrasonographic examinations, the migration period of the genital tubercle (GT) in sheep fetuses derived from Natural Mating or embryo transfer and to compare the accuracy of a single examination with repeated examinations at short intervals. For this purpose, transrectal ultrasound was performed, using a double-frequency linear transducer (6.0 and 8.0 MHz) for monitoring 51 sheep fetuses distributed in three experimental groups (EI, EII and EIII). The fetuses in EI (n = 23) and EII (n = 18) derived, respectively, from Natural Mating and embryo transfer were monitored at 48-h intervals from the 30th to 60th day of gestation and sexed based on the final location of the GT. The fetuses in EIII (n = 10), which originated from embryo transfer, were examined only once on the 65th day of gestation and sexed taking into consideration the final position of the GT and/or by identification of anatomical structures of external genitalia. The accuracy of fetal sexing was 91.3% (21 fetuses sexed/23 quantified) in EI, 88.9% (16 sexed/18 quantified) in EII and 100% (10 sexed/10 quantified) in EIII, without significant difference (P > 0.05) between experiments. Migration of the GT occurred earlier (P < 0.05) in fetuses produced by Natural Mating (43.0 +/- 2.8 days) than in those derived from embryo transfer (46.1 +/- 4.7 days). The results show that fetal sexing can be done from the 50th day onward in fetuses produced by Natural Mating and from the 60th day onward in fetuses derived from frozen embryos. It can also be concluded that repeated ultrasonographic exams in short time intervals do not maximise the accuracy of fetal sexing. In addition, real-time ultrasonography is a reliable tool for fetal sex determination in sheep after Day 50 of gestation, taking into account both the location of the GT and the identification of external genital structures.
Eduardo Luiz Cavalcanti Caldas - One of the best experts on this subject based on the ideXlab platform.
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ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer
Journal of Reproduction and Development, 2010Co-Authors: Leopoldo Mayer Freitas Neto, M H B Santos, Paulo Fernandes de Lima, C R Aguiar Filho, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Jose Monteiro Almeida Irmao, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P<0.05) in NM (42.21 ± 2.86 days) than in FrE (43.98 ± 3.00 days), FE (44.97 ± 1.83 days) and VE (44.58 ± 1.97days). Visualization of the scrotal bag, prepuce and vulva occurred, respectively, earlier (P<0.05) in NM (45.22 ± 1.25, 45.95 ± 1.53 and 45.01 ± 1.03 days) than in FrE (48.91 ± 1.92, 48.52 ± 1.41 and 47.41 ± 1.41 days), FE (49.97 ± 1.08, 49.18 ± 2.00 and 47.64 ± 1.82 days) and VE (50.12 ± 1.66, 49.27 ± 1.61 and 47.93 ± 1.92 days). The results show that fetal sexing can be accomplished from the 50th day onward in fetuses produced by Natural Mating and from the 55th day onward in fetuses derived from fresh, frozen and vitrified embryos. It can also be concluded that real-time ultrasonography is a reliable tool for fetal sex determination in sheep taking into account both the location of the genital tubercle and the identification of external genital structures.
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Reliability of ultrasound for early sexing of goat fetuses derived from Natural Mating and from fresh, frozen and vitrified embryo transfer.
Reproduction, fertility, and development, 2010Co-Authors: L M Freitas Neto, Paulo Fernandes de Lima, Maico Henrique Barbosa dos Santos, C R Aguiar Filho, E R Santos Junior, José Monteiro de Almeida Irmão, Eduardo Luiz Cavalcanti Caldas, Marcos Antonio Lemos de OliveiraAbstract:The aim of the present study was to identify the migration period of the genital tubercle and its later differentiation into external genital structures in fetuses derived from Natural Mating and fetuses from fresh, frozen and vitrified embryo transfer. A transrectal ultrasound with a double-frequency linear transducer (6.0 and 8.0 MHz) was used to monitor 123 goat fetuses, which were allocated to one of four groups: fetuses originating from controlled Natural Mating (G1, n = 32) and fetuses derived from fresh (G2, n = 34), frozen (G3, n = 30) and vitrified (G4, n = 27) embryo transfer. The transferable embryos were collected 7 days after Mating by laparoscopy. Migration of the genital tubercle occurred significantly earlier (P < 0.05) in G1 than in G2, G3 and G4. The visualisation of the scrotum, prepuce and vulva occurred significantly earlier (P < 0.05) in G1 than in G2, G3 and G4. Our results show that fetal sexing is feasible after 55 days for fetuses from Natural Mating and after 60 days in fetuses from fresh and cryopreserved embryos. Thus, real-time ultrasonography is a reliable tool for fetal sex determination in goats after Day 50 of pregnancy, taking into account both the location of the genital tubercle and the identification of external genital structures.
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Ultrasonographic fetal sex identification in pregnant sheep derived from Natural Mating and embryo transfer.
The Journal of reproduction and development, 2010Co-Authors: Leopoldo Mayer de Freitas Neto, Paulo Fernandes de Lima, Maico Henrique Barbosa dos Santos, Cristiano Rocha de Aguiar Filho, José Monteiro de Almeida Irmão, Eduardo Luiz Cavalcanti Caldas, Jairo Pereira Neves, Marcos Antonio Lemos de OliveiraAbstract:The objective of this study was to identify the migration period of the genital tubercle and the period of visualization of external genital structures in fetuses of the Dorper breed of sheep derived from Natural Mating and from fresh, frozen and vitrified embryo transfer. Transrectal ultrasound was performed using a double-frequency linear transducer (6.0 and 8.0 MHz) to monitor 130 ewe fetuses distributed in the four treatments regarding embryo origin. The accuracy of the ultrasound was 100% in this experiment. The fetuses originated from controlled Natural Mating (NM) and from fresh (FrE), frozen (FE) and vitrified (VE) embryo transfer, with embryos collected 7 days after breeding. Migration of the genital tubercle occurred earlier (P
