Characterization of forages by differential scanning calorimetry and prediction of their chemical composition and nutritive value

Differential scanning calorimetry (DSC) measurements of grass and legume hay samples were made to determine the potential of using this technique to estimate forage chemical composition and cattle intake and digestibility parameters. Ninety-three hay samples were examined, with 56 samples being used for development of calibration equations relating 17 forage chemical parameters and animal measurements to heat fluxes in response to temperature changes in forage samples, and the remaining 37 samples for validating the equations. Percentages of crude protein, neutral detergent fibre, and ash were the only chemical parameters which could be predicted with some accuracy (R2=0.61, 0.72 and 0.46; SE=1.91, 3.84 and 1.19 respectively). The proportion of variation in animal dry matter intake and digestibility which could be accounted for by the DSC technique was only 20 and 13%, respectively (P>0.05). It was concluded that the DSC technique was not practically useful for predicting forage composition or nutritive value.