The in vitro prediction of herbage digestibility

K.R. Drew

Invermay Research Station, Mosgiel

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Proceedings of the New Zealand Society of Animal Production. 1966, 26: 52-70

Experiments have been conducted to determine the most suitable in vitro method for predicting herbage digestibility. Incubation of the test forage with a measured quantity of rumen fluid from a grass fed fistulated animal for 72 hours followed by a further 24 hours in acid pepsin gave in vitro digestibilities very close to in vivo figures. A relationship of y = 1.014 x where y = in vivo organic matter digestibility and x = in vitro organic matter digestibility was established. Week to week variation was greatly reduced when this method was used rather than a 48-hour micro-organism digestion followed by a 48-hour pepsin digestion. Duration of incubation and source of rumen liquor are examined as major factors affecting the in vivo : in vitro relationship.

Keywords: NZSAPAB;

Last Updated 24-08-2000