What it is
ADF measures the cellulose and lignin in a feed [1]. It also contains small amounts of bound protein, cutin, silica and pentosans [2].
What it tells you
ADF is negatively correlated with digestibility [1]. Higher ADF usually means less digestible dry matter and less energy available; ADF rises as plants mature, so cutting forage early is an easy way to increase its available energy [3].
Oregon forages generally range from 24% to 51% ADF on a dry matter basis [1].
See also ndf, crude fibre, digestible energy.
Sources
- 1. Arispe S, Filley S. Understanding your forage test results (EM 8801). Oregon State University Extension Service. Revised October 2020, reviewed 2023. https://extension.oregonstate.edu/catalog/em-8801-understanding-your-forage-test-results (accessed 2026-11-07)
- 2. Van Soest PJ. Effect of environment and quality of fibre on the nutritive value of crop residues. In: Plant breeding and the nutritive value of crop residues. Food and Agriculture Organization of the United Nations (FAO). Undated (references to 1987). https://www.fao.org/4/x5495e/x5495e06.htm (accessed 2026-11-07)
- 3. A&L Canada Laboratories. Defining Analytical Constituents in Equine Feed Reports. Fact Sheet No. 234. London, Ontario. Revised February 2022. https://alcanada.com/Tech_Bulletins/Field_Crops/Forages/234-Defining%20Analytical%20Constituents%20in%20Equine%20Feed%20Report.pdf (accessed 2026-11-07)
Last edited 7 Nov 2026, 1:48 am