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Resumen
Además de las mediciones tradicionales de cambios en el peso y la condición corporal, los niveles de nitrógeno uréico en sangre (BUN) o en leche (MUN) pueden utilizarse como herramientas para estimar el estado de la nutrición energético-proteínica del ganado. En vacas y novillos sanos, las concentraciones de nitrógeno uréico por debajo de 7 mg/ dL indican deficiencias de proteína (nitrógeno) en la dieta con relación al consumo de energía digestible. En el ganado vacuno de rápido crecimiento o las vacas lecheras de alta producción, las concentraciones de nitrógeno uréico menores de 15 mg/ dL señalan una deficiencia relativa de proteína en la dieta. Las concentraciones de nitrógeno uréico mayores de 19 a 20 mg/dL, se han asociado con una reducción de las tasas de concepción y preñez en vacas lecheras.
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