Milk Efficiency Calculator

Increasing Milk Production & Efficiency in Cows


Calculating Milk Efficiency

High feed and/or low milk price often prompts dairy producers to look for avenues to reduce production costs. Often, the first step is a general instruction to reduce diet cost. This attempt to minimize ingredient cost may be actually counterproductive and more costly to dairy producers. The goal of producing milk is to maximize income over feed cost (IOFC). Maximizing IOFC depends on maximizing milk production from inputs (ration) given to the cow. Therefore, the primary goal is to reach the maximum milk efficiency (ME) potential. Below are some major factors affecting income over feed cost:

  • Herd management
  • Forage quality
  • Milk efficiency

Milk efficiency (ME) is a good indicator of ration profitability by comparing feed to milk yield. Milk efficiency describes a dairy cow’s performance by comparing the cow’s total milk yield to the amount of dry matter that it consumes. Milk efficiency is equal to milk yield divided by dry matter intake (DMI):


Milk efficiency is closely related to the energy density of the ration. Depending on the net energy of diet of your ration, you should expect a certain level of milk efficiency, per the chart below:

Chart pertains to 100 lbs milk, 3.7% fat, 3.5% protein


Importance of Milk Efficiency

Many dairy cows have milk efficiency of 1.4-1.7. Yet, most could yield milk efficiency of 1.9 or greater. Diet formulation programs can be used to assess a herd’s milk efficiency potential. But why is milk efficiency an important metric? If the diet cost is $6.50 per day, as shown in the data table below, milk price is $13 per cwt, and herd milk efficiency is 1.6 with a diet energy milk efficiency potential of 1.9, the dairy is missing an opportunity for $2.15 increased IOFC per cow per day.


DMI (Lbs.) 55
Feed cost per day $6.50
Milk Price ($cwt)  $13.00
Milk Efficiency Milk Production Milk Value IOFC
1.4 77.0 $10.01 $3.51 $0.72 saving
1.5 82.5 $10.73 $4.23
1.6 88.0 $11.44 $4.94
1.7 93.5 $12.16 $5.66
1.8 99.0 $12.87 $6.37 $2.15 saving
1.9 104.5 $13.59 $7.09
2.0 110.0 $14.30 $7.80
2.1 115.5 $15.02 $8.52


There are several management, environment and nutritional factors that can reduce milk efficiency of dairy cows. However, it is impossible to maximize milk efficiency if a diary cow’s amino acid requirements are not met. Because milk efficiency impacts IOFC, maximizing milk efficiency is essential to maximizing IOFC. Using $6.5 diet cost per day and $13 per cwt milk price, each 0.1 increase in milk efficiency is worth $0.72 IOFC per cow per day. If an ingredient is pulled from a diet that is costing $0.35 per cow per day but reduces milk efficiency by only 0.1 unit, the cost incurred ($0.72) is much greater than the reduced expense of $0.35.

Therefore, it is crucial to evaluate the diet formulation and assess the value of dietary ingredients for dairy farmers. Rumen-protected amino acids play an important role in improving milk efficiency, with its net IOFC benefit outweighing its cost. A gap between the current milk efficiency and maximum potential milk efficiency of a herd indicates a potential economic benefit when a diet is balanced to meet a cow’s amino acid requirement. Using rumen-protected amino acids, such as AjiPro®-L, to balance lactation diets can have positive effects on milk efficiency and improve IOFC even when milk price is low.

Improving IOFC requires:

  • Formulation reevaluation
  • Balancing amino acids to increase milk efficiency

Using AjiPro®-L can improve income over feed cost (IOFC).


Milk Efficiency Calculator

Compare your current milk efficiency with maximum potential milk efficiency by entering data in the calculator below:

Mcal/lb of Diet dry matter
Mcal/lb of Diet dry matter
(Please note that the calculator is designed for Holstein dairy cow diet only)

Your Results

Current Milk Efficiency:

Potential Milk Efficiency:

Current IOFC per cow per day:

Potential IOFC per cow per day:


The figures that you have entered above have created an outcome that is not possible. Please revise your figures and click on the "Recalculate" button again.

Open additional data

NE Required for maintanance

NE Required for lactation

NE Required for maintanance + lactation

NE consumed

Current Diet intake on DM basis

Min Diet intake Required on DM basis