Mechanistic Equations to Represent Digestion and Fermentation

  • Richard A. Kohn
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 537)


Current mathematical models use different forms of equations to represent feed degradation and microbial fermentation in the rumen. For example, the Cornell Net Carbohydrate and Protein System (CNCPS; Sniffen et al., 1992) assumes that feed digestion rate is first order with respect to substrate, but the models of Baldwin et al. (1987) and Dijkstra et al. (1992) assume Michaelis-Menten kinetics. A model proposed by Kohn and Boston (2000) suggests an alternative form of equations that incorporates the Second Law of Thermodynamics to represent fermentation processes in the rumen. The purpose of this paper is to explore the differences among these approaches, including the form of the equations, the theoretical basis and assumptions, and the behavior. This analysis will identify a number of important research questions to pursue.


Methane Production Volatile Fatty Acid Concentration ofES Mechanistic Equation Propionate Production 
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Copyright information

© Springer Science+Business Media New York 2003

Authors and Affiliations

  • Richard A. Kohn
    • 1
    • 2
  1. 1.University of MarylandDepartment of Animal and Avian ScienceCollege Park
  2. 2.University of MarylandDepartment of Animal and Avian SciencesCollege Park

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