The ability of proanthocyanidins (PA) to form insoluble complexes with proteins and polysaccharides affects fiber digestion and analysis. This review discusses these effects in relationship to the application of the detergent system of forage analysis. A fraction of the PA in plants remains after extraction for analysis. Insoluble PA may be a natural part of the plant cell wall or may be insoluble because of high molecular weight and post harvest reactions. These reactions increase the amount of insoluble PA and decrease the amount of soluble PA. The butanol-HCl assay is the most suitable method for analysis of insoluble PA. Insoluble PA are associated with negative apparent digestion coefficients for acid-detergent lignin (ADL), neutral-detergent insoluble N and acid-detergent insoluble N. The addition of sodium sulfite to neutral detergent eliminates insoluble PA from NDF. However, the addition of sodium sulfite to neutral detergent will give misleading results in relationship to true digestibility of protein. The difference between fiber fractions that are prepared with and without the addition of sodium sulfite to neutral-detergent may estimate the amount of PA/protein complex associated with NDF. A better understanding of the relationship between PA structure and function is necessary to manipulate PA in forages through breeding or genetic engineering. The interaction between PA and fiber analysis and digestion is an important component of this research. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020
Scholarly peer-reviewed articles published by the Society for Range Management. Access articles on a rolling-window basis from vol. 1, 1948 up to 5 years from the current year. Formerly Journal of Range Management (JRM). More recent content is available by subscription from SRM.