When milk prices and dairy profit margins are good, such as 2014, we sometimes get comfortable with production and on-farm efficiency. With today’s low milk prices and rising feed protein prices, now is the time to fine-tune rations to enhance microbial growth in the rumen.
Why should we do this? With a good, controlled fermentation (controlling pH or acidity) in the rumen, we will do two things: First, we will maximize the energy derived from the fiber, starch and other carbohydrates fed, and secondly, we will optimize microbial protein flow from the rumen. This results in high-quality protein production in the rumen and can reduce the need to feed more expensive ingredients to meet the energy and amino acid requirements of the cow.
Meeting the needs of the rumen microbiome is in many ways more complicated than meeting the needs of the cow. When the needs are not met correctly, individual microbes in the rumen reduce their growth and change their fermentation behavior. This results in the production of unwanted fermentation acids, like lactic acid, which reduce rumen pH.
One of the biggest requirements is for rumen degradable protein (RDP), which provides nitrogen in the forms of ammonia (NH3) and amino acids from proteins degraded in the rumen. With the right blend of nitrogen sources, fiber digestibility is enhanced; resulting in a more controlled acidity in the rumen.
Additionally, the fermentation results in a higher production of acetate and butyrate, enhancing milkfat production by the cow. The goal should be to maintain a level of ruminal NH3 that optimizes microbial activity and to avoid situations where NH3 is wasted (too high) or is insufficient (too low) to support optimal microbial activity.
The challenge we have is that microbial digestion of fiber is slower than digestion of starch and other carbohydrates. This discrepancy in the rate of digestion of various carbohydrates has become more of a challenge recently, because there has been a push to reduce the amount of protein we feed to cows.
This change results in a bigger challenge in providing the NH3 and amino acids needed by the fiber-digesting bacteria for fiber digestion. We have oversimplified ration formulation by adding raw urea and relying on the NH3 coming from the rapid breakdown of the forage protein sources.
We need to provide a steadier release of NH3 in the rumen to balance the needs of the slower-growing, fiber-digesting bacteria and avoid the peaks and valleys in ruminal NH3 that can occur with inconsistent meal patterns (Figure 1).
This is where the relatively new technology of a microencapsulated nonprotein nitrogen (NPN) source can better meet the needs of the fiber-digesting bacteria. Research has shown that with this technology, fiber digestibility is enhanced, rumen pH is better controlled and microbial yield is increased, increasing metabolizable amino acid supply to the cow.
When properly formulated into diets at rates up to 0.4 pounds per cow per day, a microencapsulated NPN source can deliver the following benefits:
- Increased microbial protein yield
- Increased fiber digestibility
- Increased yield of milk, milkfat and/or milk protein (Table 1)
- Create space in the diet (0.2 pounds of microencapsulated NPN can replace in excess of 1 pound of soybean meal or 1.4 pounds of canola meal), providing formulation flexibility
- May result in moderate diet cost savings, depending on the price of feed proteins and formulation strategies
- Can reduce out-of-pocket feed costs
Talk to your nutritionist to see if microencapsulated NPN can benefit your cows and improve ration efficiency. 
Clay Zimmerman is a ruminant nutritionist with Balchem Animal Nutrition & Health.
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Charlie Sniffen
- President
- Fencrest LLC
