Answer provided by Mike Hutjens, extension dairy specialist at the University of Illinois, Urbana.
Q: With the current price of milk ($12/cwt.) and milk protein ($2.20 a pound), is adding rumen-protected amino acids to the ration economically justified?
A: If the herd is marketing in a fluid-based milk market (does not pay for milk protein), the decision will depend on whether the herd responds with enough milk to cover costs and move closer to the desired profit margin. For example, if milk is priced at 12 cents a pound and the amount of rumen-protected amino acid added costs 18 cents, the herd average has to increase by greater than 1.5 pounds of milk per cow.
If the herd is in a milk-component-based market (milk price is based on pounds of true protein and milk fat produced), a similar comparison can be conducted, but is more favorable, especially if milk protein test is below the breed average. For example, if a herd averages 80 pounds of milk and the addition of rumen-protected amino acid increases milk protein test by 0.1 point (from 2.9 percent to 3 percent), the increase in milk protein is 0.08 pound of protein times $2.20 per pound of protein or 17.6 cents per cow per day. If the needed amount of rumen-protected amino acid costs less than 17.6 cents, the decision is economically justified. If milk yield also increases, additional economic benefits are realized.
The following points may be helpful in making the correct decision.
- A computer-software program with a rumen model is critical to estimate current amino acid levels in the current ration to evaluate the level and balance of amino acids delivered to the herd.
- Review the current herd milk protein test. A normal true milk protein test for Holsteins is 2.98, while for Jerseys, the value is 3.55 percent.
- If you add the rumen-protected amino acids, the herd could respond in one to two weeks after supplementation was initiated.
Response to supplemental amino acids varies from zero to 0.2 point of true protein.