Towards Future Feed Evaluation Systems

  • M. Ryle
  • E. R. Ørskov


It was shown in Chapter 8 that the intake of straw by steers could be predicted quite accurately from information on the degradation characteristics of the feed, generated from the formula p = a + b (1 — e-et). In the same way, M. Gill & Y. Nakashima (personal communication) predicted with similar accuracy the intake of silage-baseddiets by sheep. This formula has generated useful information relating to the restrictions of gut capacity. The soluble material a contained in roughage contributes little to rumen fill. In contrast, the insoluble but fermentable material b contributes to the volume occupied initially, and the rate constant c determines the duration of its diminishing occupation. The insoluble and indigestible material, 100 (a + b), occupies a constant volume until voided.


Wheat Straw Rice Straw Outflow Rate Degradation Rate Constant Fermentable Material 
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Copyright information

© Elsevier Science Publishers Ltd 1990

Authors and Affiliations

  • M. Ryle
    • 1
  • E. R. Ørskov
    • 2
  1. 1.Stocksbridge, SheffieldUK
  2. 2.Applied Research DepartmentThe Rowett Research InstituteUK

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