Advances in Ration Formulation

September 2015

Much has changed in our understanding of dairy rations over the years. Historically, the National Research Council (NRC) has been seen as the definitive voice when it comes to feeding livestock. However, the latest version of its “Nutrient Requirements of Dairy Cattle” was published in 2001 – leaving more than 14 years of new findings that need to be considered.

NRC is at work updating “Nutrient Requirements of Dairy Cattle,” and since its last publication, there have been significant technological advances that have improved our ability to formulate dairy rations. One of the biggest changes has been in how feed ingredients are analyzed.

New analyses have been developed to meet current needs and reflect new research. Two areas this has affected include:

1. Protein evaluation: Soluble protein is no longer equated with degraded protein.
2. Predicting energy: Lignin values are no longer part of the estimation for indigestible neutral detergent fiber (NDF) and energy.

Being able to accurately assess protein has helped shed light on canola’s use as a protein ingredient source. We now know the importance of bypass protein to the cow, and canola has more bypass protein than other popular protein sources. Additionally, the change in estimating indigestible NDF and energy has changed how canola is viewed as an ingredient, as it does not have low fiber digestibility as previously thought.

Forage testing labs have made assessments of feed ingredients easier for nutritionists, and newer ration formulation software has helped them as well. By combining these new technologies, nutritionists can choose the right ingredient source based on what we now know about dairy ration needs and feed ingredients.