Sincronización del estro y ovulación en hembras bovinas de razas cárnicas. Bases endocrinas y protocolos usados
Palabras clave:
ciclo estral, olas de crecimiento folicular, sincronización de estro y ovulación, vacas productoras de carneResumen
En México, la eficiencia reproductiva de las vacas en los sistemas de producción de becerro es baja y el uso de esquemas de sincronización del estro y la ovulación puede contribuir a mejorarla. El objetivo de esta revisión fue describir la regulación endocrina del ciclo estral y la dinámica folicular en los bovinos, resaltando cómo, a través del uso de hormonas exógenas se pueden manipular estos procesos para implementar los diferentes protocolos de sincronización del estro y la ovulación. Además, se presentan resultados de tasa de preñez a estro sincronizado (TPES) con los diferentes protocolos de sincronización de estro y ovulación que se reportan en la bibliografía. Se recopilaron revisiones y artículos originales sobre temas de ciclo estral y desarrollo folicular en bovinos y se obtuvieron datos de TPES de artículos científicos publicados entre 2000 y 2023. La TPES reportada oscila entre 23 hasta 76%, sin embargo, aunque el rango es amplio, en protocolos basados en estradiol y GnRH alrededor del 50% de los datos de TPES colectados están entre 45 y 55%. En protocolos basados en progesterona el 50% de los datos reportan TPES de entre 55 y 65%. En la actualidad, existen tres principales protocolos de sincronización de estro y ovulación con los que, según la bibliografía revisada, se puede obtener TPES de entre 45 y 65% en la mayoría de las ocasiones.
http://dx.doi.org/10.21929/abavet2023.16
e2022-11
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