Elaboration of a multi-variate model for the determination of the metabolizable energy of Mediterranean bushes based on chemical parameters

Detailed information has been collected on the nutritional value of forbs and shrubs in various Mediterranean areas of Spain using the parameters of crude protein, crude fat, acid detergent fibre, neutral detergent fibre, acid detergent lignin, cellulose, hemicellulose, chlorides, silicon, ash and other minerals. These parameters were the independent variables of a multi-variate model in which the metabolizable energy (ME) was the dependent variable. The results indicate that the model allows for a quick and reliable determination of ME (R-2 = 0.989, F= 1561.2; p<0.001; S.E.= 1.12) for Mediterranean bushes, and is particularly suitable for those studies in which a large number of samples distributed in time or in different geographical areas are evaluated. In our region, this type of analysis may in future be carried out at low cost and high reliability, since the results reported here are based on a large quantity of data from many species of eight areas of Mediterranean Spain, under various environments. (C) 2002 Elsevier Science Ltd.