Session 8: Improved Grassland Machanization and Cropping Systems Including a Section Dealing with Improved Research Techniques for Laboratory and Field Evaluation of Forages
Publication Date
1985
Location
Kyoto Japan
Description
The prediction of the nutritive value of fresh herbage in the UK is currently based on the measurement of modified acid detergent fibre (MADF). The prediction equations used are derived from in vivo measurements made up to 1969. Subsequently Barber et al. (1984) published data on the suitability of a range of predictors indicating the superiority of the neutral detergent fibre cellulase (NCD) technique over MADF. However, this information was based on experiments carried out in one laboratory and variability between laboratories in the measurement of the predictor is an important factor when deciding which predictor is most suitable for use on a national basis. A ring test was therefore undertaken comparing within and between laboratory variability for both MADF and NCD. Between laboratory variability was greater for NCD than MADF, however when this was built into the standard error of prediction, NCD remained a superior predictor of both digestible organic matter content and metabolisable energy. The new equations provide a similar prediction to those currently in use in the UK at high DOMD contents, but predict approximatery 5 % units higher at low DOMD contents, eg. 65 % instead of 60 %. This would have considerable impact on established advice, particularly that given in relation to silage making.
Citation
Adamson, A H.; Givens, D I.; and Barber, W P., "Prediction of the Nutritive Value of Fresh Herbage in the UK" (1985). IGC Proceedings (1985-2023). 5.
(URL: https://uknowledge.uky.edu/igc/1985/ses8/5)
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Prediction of the Nutritive Value of Fresh Herbage in the UK
Kyoto Japan
The prediction of the nutritive value of fresh herbage in the UK is currently based on the measurement of modified acid detergent fibre (MADF). The prediction equations used are derived from in vivo measurements made up to 1969. Subsequently Barber et al. (1984) published data on the suitability of a range of predictors indicating the superiority of the neutral detergent fibre cellulase (NCD) technique over MADF. However, this information was based on experiments carried out in one laboratory and variability between laboratories in the measurement of the predictor is an important factor when deciding which predictor is most suitable for use on a national basis. A ring test was therefore undertaken comparing within and between laboratory variability for both MADF and NCD. Between laboratory variability was greater for NCD than MADF, however when this was built into the standard error of prediction, NCD remained a superior predictor of both digestible organic matter content and metabolisable energy. The new equations provide a similar prediction to those currently in use in the UK at high DOMD contents, but predict approximatery 5 % units higher at low DOMD contents, eg. 65 % instead of 60 %. This would have considerable impact on established advice, particularly that given in relation to silage making.
