Primerjava dveh metod za določanje vsebnosti vlaknine v voluminozni krmi

Andrej LAVRENČIČ; Andrej OREŠNIK; Andreja BRANK

doi:10.14720/aas.2003.82.2.15276

Authors

Andrej LAVRENČIČ Univ. of Ljubljana, Biotechnical Fac., Dept. of Animal Science., Groblje 3, SI-1230 Domžale, Slovenia
Andrej OREŠNIK Univ. of Ljubljana, Biotechnical Fac., Dept. of Animal Science., Groblje 3, SI-1230 Domžale, Slovenia
Andreja BRANK Kranjska pot 9, SI-1218 Komenda, Slovenija

DOI:

https://doi.org/10.14720/aas.2003.82.2.15276

Keywords:

animal nutrition, forages, grasses, red clover, fiber, determination, methods, filter bag method, comparison

Abstract

In 76 samples of Italian ryegrass, perennial ryegrass, timothy and red clover, harvested in different morphological stages, the crude fibre (CF) content was determined according to the method of Naumann and Bassler (1976) and neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL) were determined according to the methods of Goering and Van Soest (1970). CF, NDF, ADF and ADL contents of the same samples were also determined with the use of filter bags and labelled as CF_FB, NDF_FB, ADF_FB and ADL_FB. In contrast to grasses, where the differences between NDF and NDF_FB, ADF in ADF_FB and ADL in ADL_FB were small (in average the largest difference was 20 g kg^–1 DM between ADF and ADF_FB in perennial ryegrass), the differences between NDF and NDF_FB, ADF and ADF_FB, ADL and ADL_FB contents in red clover were large (in average 46, 66 and 35 g kg^–1 DM, respectively). The differences between CF and CF_FB contents in grasses and red clover were not so large (in average teh largest difference was 17 g kg^–1 DM in red clover). If the samples of red clover were rinsed with acetone before NDF_FB, ADF_FB and ADL_FB contents determination (acNDF_FB, acADF_FB and acADL_FB) the differences between them and NDF, ADF and ADL contents greatly diminished (in average to 15, 17 and 5 g kg^–1 DM, respectively). The accuracy of the relationship between CF, NDF, ADF and ADL contents and fibre contents determined with the filter bags was measured with the coefficient of determination (R²) in standard error of the estimate (SEE). The best predictions for CF (R² = 0.89, SEE = 1.73), NDF (R² = 0.98, SEE = 1.73), ADF (R² = 0.90, SEE = 1.73) and ADL (R² = 0.69, SEE = 1.73) contents were those which contained as a single dependent variable CF_FB, NDF_FB, ADF_FB and ADL_FB of grasses and CF_FB, acNDF_FB, acADF_FB and acADL_FB of red clover. Results showed that the filter bag method is convenient for the determination of the CF, NDF and ADF contents, but is less suitable for the determination of ADF content.