Why AjiPro®-L Lysine

Nutritionists’ No. 1 Choice¹


AjiPro®-L is the dairy industry’s leading rumen protected lysine

With documented 80% rumen bypass and 80% intestinal digestibility to result in 64% bioavailability, it is a highly bypassable, digestible and available source of lysine for the high-producing dairy cow. These high-quality standards have earned no. 1 brand recognition from nutritionists compared to other competitor brands.

AjiPro®-L is the lowest cost metabolizable lysine per unit. And it offers dairy nutritionists flexibility in feed formulation by allowing them to raise the proportion of lysine in total metabolizable protein (Lys/MP ratio).

Using AjiPro®-L benefits the farmer and the farm. It can:

  • Increase milk production.
  • Increase income over feed cost.
  • Reduce nitrogen excretion.

How AjiPro®-L delivers results

At its core, AjiPro®-L consists of a matrix of L-Lysine-HCl and vegetable oil that resists breakdown as it passes through the rumen. AjiPro®-L’s hydrogenated vegetable oil matrix resists physical damage while its hydrophobic layer prevents the microbial breakdown of lysine.

When properly formulated into a ration, AjiPro®-L delivers a consistent amount of lysine for absorption by dairy cows. This helps balance amino acids in the diet, thereby improving the lactating performance. For more research on AjiPro®-L, click here.

Intestinal Digestibility

Given its high digestibility, AjiPro®-L is designed for maximum absorption, as shown in the figure below.


AjiPro®-L specifications


L-lysine content
40% minimum on dry matter basis

Dry matter
No less than 95%

Specific Gravity
1.10-1.15 g/cm³

AjiPro®-L is composed of:

  • Minimum 50% L-Lysine monohydrochloride (6.11 AAFCO)
  • Approx. 49% Vegetable oil (33.2 AAFCO)
  • Approx. 1% Lecithin (87.5 AAFCO)


What is lysine?

Lysine is an essential amino acid for cows. Cows require 10 essential amino acids to build protein, and of all of these, lysine is most often in short supply and the first to limit protein synthesis. Lysine deficiency often results from a diet that is low in lysine. Common feed ingredients that are low in lysine include corn and corn silage. (In general, and for humans too, vegetable-based diets are lower in lysine.)

When dairy cows experience lysine deficiency in their diet, their milk production and milk protein yield fall short of their potential, resulting in a loss of profitability.

AjiPro®-L is a research proven lysine source that can play a significant role in increasing a dairy cow’s milk efficiency, thereby increasing income over feed.

Lysine supplements

Lysine must be supplemented in a cow’s diet, as cows cannot synthesize it themselves. In the past, excess protein was fed to meet the lysine requirement.

Today common sources of lysine for dairy cows include:

  • Animal byproduct, such as blood meal and bone meal.
  • Soy and soy byproduct.
  • Rumen-protected lysine.

While high-protein supplements like blood meal remain in common practice, there are costs to consider:

  • Batches of blood meal may vary one to the next.2
  • Prices may vary with market shifts.
  • Even when prices are low, feeding blood meal may deliver wasted nutrients; the lysine it contains may not be digestible to the cow.

Rumen protected lysine

A rumen protected lysine supplement protects the amino acid, allowing it to reach the small intestine for maximum absorption. Studies have demonstrated that today’s high-producing dairy cows respond to higher levels of dietary lysine and produce more milk and milk components when their diets are supplemented in the form of rumen protected lysine.

AjiPro®-L can help minimize the excess cost coming from protein sources by delivering a consistent amount of lysine to maximize milk efficiency and income over feed.



  1. Data from the survey conducted in September 2018 and sponsored by Ajinomoto Animal Nutrition North America.
  2. Knapp, J. and St.Pierre, N. (2011) Blood meal variability affects dairy performance. Feedstuffs Vol. 83, No. 10.

Assuring Quality Testing

It’s our mission to expand high-quality products and services in animal nutrition, to pioneer innovative solutions and satisfy customer needs for safe and sustainable products. Follow the link to view our Certificate of Analysis.

Certificate of analysis