Concentración de urea en plasma y respuesta productiva de cerdos en iniciación alimentados con dietas sorgo-pasta de soya bajas en proteína

Agrociencia (Impact Factor: 0.26).
Source: OAI

ABSTRACT Existe poca información acerca del uso de dietas con baja proteína cruda (PC) para cerdos en iniciación. Por tanto, se realizaron dos experimentos para determinar el porcentaje mínimo de PC en dietas sorgo-pasta de soya que no afecte el comportamiento productivo, utilizando urea en plasma como indicador. En el experimento 1, los tratamientos (% PC) fueron: T1) testigo 20.5; T2) 19.0; T3) 17.5; T4) 16.0; T5) 14.5, y se aplicaron a 10 cerditas en iniciación usando un diseño cruzado con periodos de 7 d. El último día de cada periodo se obtuvo una muestra de sangre de la vena cava para determinar urea. La menor concentración de este metabolito indicó que la PC en la dieta puede reducirse hasta 16%. Mediante regresión no lineal exponencial se determinó que la PC en la dieta se puede reducir hasta 14.86% y aumentar hasta 20.12% para obtener la mínima y máxima concentración de urea en plasma. En el experimento 2, los tratamientos (%PC y Mcal EM kg-1) fueron: T1) dieta estándar, 20.5 y 3.265; T2) 20.5 y 3.165; T3) 16 y 3.265; T4) 16 y 3.165; T5) 14.5 y 3.265; T6) 14.5 y 3.165, para 24 machos castrados usando un diseño en bloques completos al azar. El menor nivel de proteína redujo la urea en plasma, mientras que al reducir la energía disminuyó la grasa dorsal y aumentó la conversión alimenticia. Lo anterior indica que la urea se reduce al disminuir la PC en la dieta; que la grasa dorsal es menor al bajar la energía; y que otros factores como el peso inicial también influyen en la respuesta de los cerdos en iniciación.

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Available from: Vicente Zamora Zamora, Sep 27, 2015
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