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Resumen
El alto contenido de fibra en forrajes tropicales y su reducida digestibilidad por los rumiantes, es uno de los más grandes limitantes para la productividad animal en el trópico. En este artículo la discusión se centra en dos grandes áreas. La primera tiene que ver con el consumo voluntario de rumiantes en pastoreo, factores que lo afectan y estrategias exitosas para incrementarlo. Debe reconocerse que, aunque de fácil determinación en animales estabulados, la estimación de este parámetro bajo condiciones de pastoreo ha sido tradicionalmente difícil e imprecisa. Estrategias como la renovación de praderas, el establecimiento de asociaciones gramínea – leguminosa y la suplementación estratégica, han sido utilizadas exitosamente para aumentar el consumo voluntario de rumiantes en pastoreo. La segunda área de discusión describe los factores que afectan la digestibilidad de la fibra en rumiantes y plantea estrategias para aumentar la degradabilidad de la fibra en el rúmen. Ambas áreas están muy relacionadas entre sí, pues del adecuado entendimiento y optimización de ambos procesos, depende gran parte de la sostenibilidad económica y ambiental de la ganadería del trópico.
Rolando Barahona Rosales, Corporación Colombiana de Investigación Agropecuaria (Agrosavia)
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