Modelling digestive and metabolic processes in animals has a prominent standing within the Animal Nutrition Group (ANU). Mathematical modelling is a central and integral part of the scientific method. Mathematical models provide a valuable means of advancing quantitative understanding of biological processes and improving our ability to predict response and performance. Models can make good use of quantitative data obtained within the experimental programmes of ANU and worldwide. The model development process can help to pinpoint areas where knowledge and/or data are lacking, and stimulate new ideas and experimental approaches. Obviously, models are used to make predictions, and provide a way of exploring possible outcomes on various nutritional strategies.
The modelling programme of ANU encompasses the main areas of ANU experimental research and deals with dairy cattle, pre-ruminant calves, pigs, and poultry. It covers the spectrum from basic to strategic and applied research on animal nutrition. The modelling approach is concerned with application, integration and understanding. Work is usually collaborative and the ANU modelling group has various collaborative projects notably with the University of Guelph (Canada), the University of California, Davis (USA), the University of Reading (UK),and the University of Leon (Spain).
The modelling research topics can be divided into two broad types of models:
- kinetic models for resolving experimental data
- mechanistic models of digestion and metabolism
Examples of application of kinetic models for describing in vitro gas production kinetics (rate of microbial substrate degradation), animal growth and lactation curves, and describing nutrient flows from the gut to productive tissues and nutrient metabolism. Examples of mechanistic models of digestion and metabolism are a model of the fermentation processes in the rumen including methanogenesis, and N- and P emissions.