Dr. Alexander Hristov, associate professor of dairy nutrition with Pennsylvania State University, said the concept of dropping crude protein levels originated as a solution to help decrease ammonia emissions.
“In our research we found that as we reduced dietary crude protein, we were able to dramatically decrease ammonia emissions, in some cases as much as 38%,” Hristov says.
This led to even more questions about what could be done with reduced protein diets to decrease ammonia emissions and nitrogen excretions.
Decreasing Ration Crude Protein
To learn more about the protein needed to meet production potential, Dr. Hristov conducted a study¹ where the treatment diet was balanced for 14% crude protein and supplemented with rumen-protected lysine and methionine. The study concluded that treatment cows maintained production levels similar to the control group, which was fed a diet with 16% crude protein. Milk protein concentration, however, was slightly reduced with the 14% crude protein diet.
Dr. Hristov indicates that reducing crude protein delivers multiple benefits to dairy producers, including:
- Reduced ration costs
- Decreased nitrogen excretion by the cow, resulting in less chance of nitrogen leaching and runoff
- Reduced ammonia emissions
He also shares that reducing dietary protein will offer another benefit in the future—meeting more stringent environmental regulations. He foresees these regulations continuing to become more common and restrictive in years to come.
More than dietary protein
While balancing diets with optimal levels of limiting amino acids provides an outstanding opportunity to maintain performance while reducing ration costs, Dr. Hristov notes the importance of properly formulating the ration for key nutrients.
“If there is anything else in the diet that is limiting production potential, lowering dietary protein levels is not going to help; it will only make things worse,” he explains. ”A few key ingredients in the diet—like high-quality forages and adequate energy—are especially important to ensure the diet delivers the nutrients required for peak performance.”
As Dr. Hristov’s research concluded, delivering optimal levels of lysine and methionine to the small intestine maximizes protein efficiency and helped to decrease dietary protein needs. More efficient protein utilization and maintained production levels lead to greater Income Over Feed Cost (IOFC) for your dairy operation.
1 “Researchers alter cow diets to help environment,” The Philadelphia Inquirer, 14 August 2010. Available at: http://www.philly.com/inquirer/health_science/daily/20100814_Researchers_alter_cow_diets_to_help_environment.html. Accessed Oct. 21, 2010.