The apparent metabolic energy (EMA) of barley is modelled as a functio
n of 12 easily obtainable analytical parameters by applying neural net
works with the error back-propagation learning strategy. Kohonen maps
and Ward's clustering technique have been used to define the objects f
or the training and test sets. The architecture of the neural network
and the relevant parameters of error back-propagation learning have be
en optimised providing a RMS of 1.081 and a correlation coefficient (p
redicted versus found values) of 0.82. Contour maps of all variables i
ncluding the output EMA value have been obtained by applying the count
er-propagation learning strategy in a two-layer neural network. The re
sponses yielded by the networks show that this method is capable of es
tablishing a quantitative relationship between EMA and the original va
riables.