The amino acid content in grass and corn/maize silages in the "CVB Table" will be updated with new research data, according to an announcement from the Wageningen University & Research (WUR) Center for Animal Nutrition in the Netherlands.
Since 2019, Wageningen Livestock Research and the Flemish Institute for Agricultural, Fisheries & Food Research (ILVO) in Belgium have oversight of the CVB program in Europe.
According to the announcement, a recent ILVO study determined that the amino acid profile of grass and maize silage (in grams per 100 g of crude protein) is hardly related to other silage characteristics, such as crude fiber in grass silages and dry matter or starch content in maize silages.
In 2019, ILVO researchers Leen Vandaele, Johan De Boever and Dorien Van Wesemael analyzed 12 grass silages and 10 maize silages. The amino acid profiles of these grass and maize silages resembled the existing values in the CVB Table quite well, WUR said.
The ILVO researchers also looked at the availability of the amino acids at the intestinal level, WUR said. The amount of ileal digestible amino acid is calculated by adding the amount of ileal digestible rumen undegradable amino acids to the amount of ileal digestible microbial amino acids and subtracting the amount of ileal digestible metabolic fecal amino acids. These calculations show that about 75% of the ileal digestible amino acids in grass and maize silages are provided by microbial protein, WUR said.
The production of microbial protein in the first place depends on the amount of fermentable organic matter in the rumen; therefore, it remains crucial to aim for high-quality grass and maize silages (with a high digestibility) for good animal performance and for the production of less-expensive roughage-based milk.
The new analytical values from ILVO will be added to the database in the CVB Table, WUR said.