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Rojas, S., (2024). Selección morfocinética de embriones bovinos con capacidad de implantación [Universidad Nacional Agraria La Molina]. https://hdl.handle.net/20.500.12996/6549
Rojas, S., Selección morfocinética de embriones bovinos con capacidad de implantación []. PE: Universidad Nacional Agraria La Molina; 2024. https://hdl.handle.net/20.500.12996/6549
@misc{renati/244761,
title = "Selección morfocinética de embriones bovinos con capacidad de implantación",
author = "Rojas Medina, Shezira Pamella",
publisher = "Universidad Nacional Agraria La Molina",
year = "2024"
}
Title: Selección morfocinética de embriones bovinos con capacidad de implantación
Authors(s): Rojas Medina, Shezira Pamella
Advisor(s): Mellisho Salas, Edwin Alberto
Keywords: Time lapse
OCDE field: https://purl.org/pe-repo/ocde/ford#4.02.00
Issue Date: 2024
Institution: Universidad Nacional Agraria La Molina
Abstract: La selección de embriones para transferencia con alta capacidad implantatoria es esencial para asegurar el éxito de la transferencia de embriones en bovinos. Sin embargo, el enfoque actual es considerado subjetivo e inadecuado debido a la variación significativa en la selección entre profesionales y laboratorios. El objetivo de este estudio fue evaluar patrones morfocinéticos del desarrollo embrionario in vitro para la selección basado en su capacidad implantatoria en bovinos. Para ello se realizaron 04 experimentos. Experimento 1, evaluación morfocinética del desarrollo embrionario a blastocisto. Experimento 2 y 3, comparación de la producción de embriones in vitro de donantes superestimuladas y no superestimuladas y experimento 4, validación del modelo matemático in vitro para la selección morfocinética de embriones bovinos con capacidad de implantación. En el experimento 1, se utilizaron ovarios de vacas de matadero local, se recuperaron ovocitos para ser madurados y fecundados in vitro. Los posibles cigotos fueron cultivados en placa de 16 micropocillos y se midieron tiempos a la división de 2 células (t2); 3 células (t3); 4 células (t4); 5 células (t5); 8 células (t8); a mórula (tM); a formación del Blastocisto (tB) y tiempo de blastocisto expandido (tBX). En experimento 2 y 3, donantes de raza Holstein y Brown Swiss fueron sometidas a sesiones de aspiración folicular guiada por ultrasonografía transvaginal previamente superovuladas (264 mg de FSH) y no superovuladas. Los blastocistos obtenidos fueron transferidos a receptoras previamente sincronizadas. El diagnostico de preñez fue determinada a los 35 días post transferencia. En el experimento 4, la validación del modelo matemático in vitro para la selección morfocinética de embriones bovinos fue realizado con el diámetro del blastocisto a la transferencia (día 7.5) y la preñez determinada a 35 días post transferencia. Las variables respuesta fueron analizados según data del experimento con la prueba ANOVA (experimento 1,2 y 3) y prueba Kruskal-Wallis (experimento 4). En experimento 1, los resultados nos indica que el tiempo medio hasta la primera escisión y hasta los blastocitos expandidos fue de 32.94 y 182.09 h, respectivamente. Aunque, el tiempo a primera escisión se redujo a 29.98 h en embriones que arribaron a blastocisto expandido exitosamente. La producción de blastocistos por donantes Holstein no superestimuladas fue de 0.65 (hato 1) y 0.31 (hato 2). Sin embargo, la producción de blastocistos por donantes Holstein superestimuladas incremento a 2.60. 11 Los blastocistos in vitro transferidos al día 7.5 post IVF de donantes superestimuladas y no superestimuladas generaron una tasa de preñez de 10,42% y 24,24% respectivamente. En el experimento 4, los resultados de validación del modelo matemático no representaron la predicción de preñez con respecto del diámetro del embrión al día 7.5. En conclusión, la tecnología time lapse nos permite evaluar a detalle el desarrollo morfocinético de los embriones que podría ayudar a la selección de los embriones más competentes para preñez de receptoras. Asimismo, las donantes superestimuladas nos permitió recolectar más ovocitos y blastocistos por donantes. Aunque el modelo matemático no permito validar con precisión la tasa de preñez, requiriendo un mayor número de repeticiones que permita mayor precisión en los resultados.
The embryo selection for transfer with high implantation capacity is essential to ensure the success of embryo transfer in bovine. However, the current approach is considered subjective and inadequate due to significant variation in selection between professionals and laboratories. The objective of this study was to evaluate morphokinetic patterns of embryonic development in vitro for selection based on their implantation capacity in cattle. For this, 04 experiments were carried out. Experiment 1, morphokinetic evaluation of embryonic development to blastocyst. Experiment 2 and 3, comparison of the in vitro embryo production from superstimulated and non- superstimulated donors and experiment 4, validation of the in vitro mathematical model for the morphokinetic selection of bovine embryos with implantation capacity. The methodology in experiment 1, oocytes were recovered from the ovaries of local slaughterhouse cows to be in vitro matured and fertilization. The possible zygotes were cultured in a 16-microwell plate and times to the division of 2 cells (t2) were measured; 3 cells (t3); 4 cells (t4); 5 cells (t5); 8 cells (t8); a morula (tM); Blastocyst formation (tB) and blastocyst time expanded (tBX). In experiments 2 and 3, Holstein and Brown Swiss donors were subjected to transvaginal ultrasonography-guided follicular aspiration sessions previously superovulated (264 mg of FSH) and not superovulated. The blastocysts obtained were transferred to previously synchronized recipients. The pregnancy diagnosis was determined 35 days after embryo transfer. In experiment 4, the validation of the in vitro mathematical model for the morphokinetic selection of bovine embryos was carried out with the diameter of the blastocyst at transfer (day 7.5) and pregnancy of receptor. The response variables were analyzed according to the experiment data with the ANOVA test (experiment 1,2 and 3) and Kruskal-Wallis test (experiment 4). In experiment 1, the results indicate that the average time until the first cleavage and the expanded blastocysts were 32.94 and 182.09 h, respectively. Although, the time to first cleavage was reduced to 29.98 h in embryos that reached a successfully expanded blastocyst. The blastocyst production by non-superstimulated Holstein donors was 0.65 (herd 1) and 0.31 (herd 2). However, blastocyst production by superstimulated Holstein donors increased until 2.60. In vitro blastocysts transferred at day 7.5 post IVF from superstimulated and non-superstimulated donors generated a pregnancy rate of 10.42% and 24.24% respectively. In experiment 4, the validation results of the mathematical model did not represent the prediction of 13 pregnancy with respect to embryo diameter at day 7.5. In conclusion, time-lapse technology allows us to evaluate in detail the morphokinetic development of embryos, which could help in the selection of the most competent embryos for pregnancy of recipients. Likewise, superstimulated donors allowed collect more oocytes and blastocysts per donor. Although the mathematical model does not allow the pregnancy rate to be precisely validated, requiring a greater number of repetitions to allow greater precision in the results.
The embryo selection for transfer with high implantation capacity is essential to ensure the success of embryo transfer in bovine. However, the current approach is considered subjective and inadequate due to significant variation in selection between professionals and laboratories. The objective of this study was to evaluate morphokinetic patterns of embryonic development in vitro for selection based on their implantation capacity in cattle. For this, 04 experiments were carried out. Experiment 1, morphokinetic evaluation of embryonic development to blastocyst. Experiment 2 and 3, comparison of the in vitro embryo production from superstimulated and non- superstimulated donors and experiment 4, validation of the in vitro mathematical model for the morphokinetic selection of bovine embryos with implantation capacity. The methodology in experiment 1, oocytes were recovered from the ovaries of local slaughterhouse cows to be in vitro matured and fertilization. The possible zygotes were cultured in a 16-microwell plate and times to the division of 2 cells (t2) were measured; 3 cells (t3); 4 cells (t4); 5 cells (t5); 8 cells (t8); a morula (tM); Blastocyst formation (tB) and blastocyst time expanded (tBX). In experiments 2 and 3, Holstein and Brown Swiss donors were subjected to transvaginal ultrasonography-guided follicular aspiration sessions previously superovulated (264 mg of FSH) and not superovulated. The blastocysts obtained were transferred to previously synchronized recipients. The pregnancy diagnosis was determined 35 days after embryo transfer. In experiment 4, the validation of the in vitro mathematical model for the morphokinetic selection of bovine embryos was carried out with the diameter of the blastocyst at transfer (day 7.5) and pregnancy of receptor. The response variables were analyzed according to the experiment data with the ANOVA test (experiment 1,2 and 3) and Kruskal-Wallis test (experiment 4). In experiment 1, the results indicate that the average time until the first cleavage and the expanded blastocysts were 32.94 and 182.09 h, respectively. Although, the time to first cleavage was reduced to 29.98 h in embryos that reached a successfully expanded blastocyst. The blastocyst production by non-superstimulated Holstein donors was 0.65 (herd 1) and 0.31 (herd 2). However, blastocyst production by superstimulated Holstein donors increased until 2.60. In vitro blastocysts transferred at day 7.5 post IVF from superstimulated and non-superstimulated donors generated a pregnancy rate of 10.42% and 24.24% respectively. In experiment 4, the validation results of the mathematical model did not represent the prediction of 13 pregnancy with respect to embryo diameter at day 7.5. In conclusion, time-lapse technology allows us to evaluate in detail the morphokinetic development of embryos, which could help in the selection of the most competent embryos for pregnancy of recipients. Likewise, superstimulated donors allowed collect more oocytes and blastocysts per donor. Although the mathematical model does not allow the pregnancy rate to be precisely validated, requiring a greater number of repetitions to allow greater precision in the results.
Link to repository: https://hdl.handle.net/20.500.12996/6549
Note: Universidad Nacional Agraria La Molina. Facultad de Zootecnia. Departamento Académico de Producción Animal
Discipline: Zootecnia
Grade or title grantor: Universidad Nacional Agraria La Molina. Facultad de Zootecnia
Grade or title: Ingeniero Zootecnista
Juror: Alvarado Malca, Armando Enrique; Gallegos Cárdenas, Amalia del Pilar; Gamarra Carrillo, Segundo Gregorio
Register date: 11-Jun-2024
This item is licensed under a Creative Commons License