Characterisation of feedstuffs for ruminants using some physical parameters

Various ingredients and roughages of known chemical composition have been analysed by several physical methods: particle density, particle size, water holding capacity, feed solubilisation and osmotic pressure. Some of these methods already exist and have been adapted and others have been newly developed. All of the methods are quite easy to perform and the results are very repeatable. The data obtained by the physical and chemical methods have been correlated together. The physical methods gave new information about the nutritive value of feedstuffs for ruminants and they can be used to differentiate between feedstuffs. They might explain part of the role played by rumen flora on feedstuffs which is not taken into account by the chemical approach.