Abstract
Near infrared reflectance spectroscopy (NIRS) was used to predict total digestible nutrients (TDN) contents of hay and grass silage. Calibration for each of hay, grass silage and those pooled samples were developed with 35, 37 and 72 samples, respectively. In addition, another samples of hay (17) and grass silage (16) were used to test the calibration equation. Samples for TDN prediction were including hay and grass silage composed mainly timothy, Italian ryegrass and alfalfa. TDN value of these feeds were obtained by digestion trials carried out with sheep. Accuracy of the prediction was evaluated by the correlation coefficients (r) and standard error of prediction (SEP). The 'r' and SEP value of TDN for all samples were 0.85-0.89 and 2.9-3.4, respectively. These results indicated that TDN contents in hay, grass silage and those pooled samples can be predicted by using NIRS techniques with an acceptable accuracy.
