Rumen Degradable Protein for Dairy: Great Ingredients Have It, Too!
The dairy nutrition industry is intently focused on rumen bypass protein ingredients, and with good reason, as it allows better performance and nutrient efficiency. We, too, are interested in this concept, as our high-shear dry extruders create highly digestible rumen bypass (RBP) protein within ingredients from our machines. In short, ingredients produced by Insta-Pro equipment, like ExPress® soy meal, provide ample, quality protein that feeds the cow and supports the production of more milk and components, like milk fat and protein. However, while the focus on bypass protein is often driven by the desire to maximize amino acid delivery to the small intestine, it’s important to remember that protein nutrition in ruminants is a balancing act, not a single metric to maximize.
The consequence of providing more digestible protein for the cow is that less protein remains in the rumen, more of it leaves and feeds the animal. However, dairy cows, like all ruminants, contain a large microbial fermentation vat called the rumen, and everything the cow consumes is altered by the rumen microbes, such as bacteria, viruses, and protozoa. While this is the goal, after all, to better feed the cow and enhance milk productivity, the rumen microbes are critically important for the overall health and well-being of the cow. For example, the rumen is the major site of the degradation of plant fibers, which are major components of dairy diets. These microbes rely heavily on a steady supply of rumen-degradable protein (RDP) to support microbial protein synthesis, which ultimately becomes one of the cow’s most valuable sources of metabolizable protein.
What happens when an ingredient with very low or overheated rumen-degradable protein is fed? As a clear example, a study carefully demonstrated that, as other important nutrient levels were maintained at constant levels, lactating dairy cows fed lower levels of rumen-degradable protein exhibited corresponding declines in milk production and components. This reduction occurs because microbes need nitrogen primarily from RDP to ferment carbohydrates effectively. Without enough RDP, carbohydrate digestion slows, volatile fatty acid production drops, and cows lose one of their primary energy sources for milk synthesis. Overheated ingredients, in particular, can create protein fractions that are indigestible to both microbes and the cow, wasting valuable nutrients and compromising performance.
So, what to do? Focusing on ingredients from a quality-minded process, like high-shear dry extrusion and ExPress® soy meal, will allow for the best of both worlds in a dairy formulation. The ExPress® process creates rumen bypass protein, as already mentioned, but it also preserves and improves all proteins, including rumen-degradable protein and bypass protein. It may be the only major ingredient for proteins that you need in your dairy formulations. By delivering a balanced profile of RDP and RBP, ExPress® soy meal supports both microbial function and intestinal amino acid supply. When the rumen environment is well-fed and stable, cows extract more energy from fiber, maintain healthier rumen pH levels, and convert nutrients more efficiently into milk and components. This dual benefit makes quality-controlled extrusion processes a strategic tool for nutritionists seeking consistency, performance, and return on investment.
