Towards Future Feed Evaluation Systems
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.
KeywordsWheat Straw Rice Straw Outflow Rate Degradation Rate Constant Fermentable Material
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