Chewing index system for predicting physical structure of the diet

Part of the EAAP – European Federation of Animal Science book series (EAAP, volume 30)


An important goal in dairy cow management is, among other things, to develop a feeding strategy that ensures good rumen function, which is vitally important for efficient milk production and healthy animals. A certain intake of physically effective fibre is essential for stimulating rumination, salivation and rumen motility, and avoiding milk fat depression (Mertens, 1997; De Brabrander et al., 2002). A high intake of rapidly fermentable carbohydrates results in the production of a high level of volatile fatty acids in the rumen and a subsequent reduction in pH, which increases the risk of subacute ruminal acidosis (Krause and Oetzel, 2006). In addition to the structural fibre content of a feed, the length of the dietary particles is also important and affects the eating time (ET), rumination time (RT) and, thus, salivation and thereby buffering of the rumen environment (Krause and Oetzel, 2006). De Boever et al. (1993) observed that one kg NDF from late cut grass silage was more effective for stimulating rumination than NDF from early cut grass silage (which has low levels of lignification), demonstrating that fibre type affects chewing activity.


Eating Time Hardness Factor Grass Silage Particle Length Dairy Breed 
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Copyright information

© Wageningen Academic Publishers 2011

Authors and Affiliations

  1. 1.TINE and the Norwegian University of Life SciencesAkershusNorway

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