Animal feeding models are used as tools to optimise diets and dietary allocations for livestock production, e.g. pig production. Current feed evaluation models have greatly improved the accuracy of farm animal feeding and increased our understanding of the digestive processes. Moreover, these models are often based on empirical relations between intake and output and apply (fixed) digestibility coefficients of nutrients in dietary ingredients.
However, the models ignore the fact that nutrient digestion is a dynamic process and that they should be based on the interactions between feed ingredients as well as interactions between the feed and the animal. For example, physicochemical characteristics of feed ingredients can affect physicochemical characteristics of the digesta and thereby passage kinetics and digestion. Therefore, the aim of the project is to design a digestion model for growing pigs based on the composition and physicochemical characteristics of feed ingredients and the diet, dietary intake and digestive processing of nutrients in the gastro-intestinal tract.
In order to predict the digestibility of nutrients from (mixtures of) feed ingredients a better understanding should be created of the complex interactions between feed ingredients, physicochemical properties of digesta, passage kinetics of digesta and digestion of nutrients. Applying this knowledge will allow more accurate modelling of the effect of these properties on the digestive processes and release of nutrients, but will also enable a more detailed description and characterisation of feed ingredients based on their functional properties in the gastro-intestinal tract. This model can be used for evaluating the effects of adjustments of feeding strategies or changes in physicochemical characteristics of feed ingredients. It will allow the pig production sector to more precisely adjust diet composition and feeding strategy of growing pigs as to minimize environmental nutrient losses.