Relationship between in vitro gas production and near infrared reflectance spectra of gliricidia provenances
The chemical composition of tropical forages is generally more complex than that of temperate forages, yet the need for simple methods to predict nutritive value is greater. Near Infrared Reflectance (NIR) spectra could provide a possible solution. NIR has been used to predict both in vitro and in vivo digestibility (Murray, 1993). Direct calibration with in vivo parameters is ideal, but factors such as different types of forages, animals and management conditions have to be taken into consideration. The gas production technique, which may be considered as an in vitro counterpart of the dacron bag technique, provides information relating to the fermentable fractions and kinetics of a forage and these parameters can be related to the NIR spectra. The aim of this study was to investigate the relationship between NIR spectra and cumulative gas production and derived parameters in tree leaves.