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Towards Future Feed Evaluation Systems

  • M. Ryle
  • E. R. Ørskov

Abstract

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.

Keywords

Wheat Straw Rice Straw Outflow Rate Degradation Rate Constant Fermentable Material 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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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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