We have all been in a parlor and heard someone say: “You better get the unit on that cow first or we will be here all day.” That cow is a slow milker, and by putting the unit on her first, we are trying to be as efficient as possible. Efficiency is key to making the milking system as profitable as possible. Milk collected per stall has been shown to impact a dairy farm's profitability significantly. Parlor turns can greatly impact milk collected per stall, and milkabilty measures of individual cows, like milking speed and milking duration, will impact how quickly cows make their way through the parlor.

Milking speed vs. milking duration

Evaluating milking speed and duration helps indicate how individual cows can impact parlor turnover. Milking speed measures the rate at which milk is collected during a given time, usually in pounds or kilograms per minute. Duration is the total unit-on time and does not account for the speed at which the cow is actively milking. Therefore, milk production has a greater impact on milking duration than it does speed. Using milk duration as a measurement of efficiency may be causing a biased view in favor of lower-producing cows.

Utilizing information

The increase in technology in the dairy industry has greatly impacted how we can make more informed decisions on farms. However, it can be challenging to know how to use the information. Automated milking systems and many parlors now have in-line sensors that can track milk flow rates. How can this information make the milking system more efficient?

Cow grouping and culling decisions are two main areas where milking speed is used to make a decision. Cows with higher milking speeds tend to have lower unit-on times, making the milking system more efficient. In an automated milking system, slow-milking cows can leave cows waiting to be milked, leading to less milk from each box. Low-milking-speed cows may be culled to prevent individual cows from impacting the total number of daily visits.

In a parlor system, milking shift times can increase if a slow cow holds up one side of the parlor. In both instances, we are worried about cow throughput in the system. Turns in the parlor can only be as fast as the slowest cow on a side. A slow cow can delay each turn when they are intermingled with cows with faster milking speeds. If cows with slower milking speeds are milked together, the milking time for only those turns will increase. Farms have seen a 30% decrease in milking shift time when they have implemented milking speed as a part of their cow grouping strategy.

Efficiency = profitability

Where the farm finds profitability of the milking system depends on whether they are using an automated milking system or parlor system. Many research papers and articles have discussed the importance of milking speed and short box times on the importance of robot profitability. The faster the cow throughput, the more cows we can milk, leading to a higher milk yield per box. Research has shown that with a 500-pound increase in milk output, farms can increase annual income by around $4,000 per robot. Reduced box time is a crucial factor in achieving lower box times.

Reduced labor cost is the main driver for parlor efficiency. Labor accounts for approximately 67% of the operation costs of running a parlor. Unfortunately, little research has examined the economics of milking speed in different systems. However, using labor statistic data with the following assumptions can give a rough estimate for labor savings by being more efficient in the parlor.

According to USDA data from November 2023, the average hourly wage for a livestock worker ranges from $12.77 per hour in the Southeast to $19.75 per hour in California, with an average of $16.48 per hour in the U.S. Being conservative and using a 20% reduction (instead of the 30% discussed earlier) in total milking shift time from eight hours to 6.4 hours, and three full-time employees working a shift, results in a labor savings of $26,350.08 per year. The opportunity cost of the employee should also be considered. Opportunity cost is the loss of potential gain from other alternatives when one alternative is chosen. This means that the farm may also be losing money from employees spending more time in the parlor than taking care of other duties on the farm.

Most farms want their parlor to be efficient but also want to make it profitable by running the parlor 23 hours a day. Let’s evaluate the potential profit from increasing herd size rather than saving labor. Using a double-12 parlor that currently has four turns per hour, a 20% increase in efficiency would result in 4.8 turns per hour. An increase in 0.8 turns per hour would allow the farm to milk 145 additional cows three times in 23 hours. Assuming the cows average 80 pounds per day at an $18 per hundredweight (cwt) milk price, the farm could gross more than $700,000 annually by becoming more efficient.

Improving milk speed

Milk speed has been shown to have a heritability of approximately 0.14. However, besides Brown Swiss, no other breeds in the U.S. offer milking speed as a genetic evaluation. Udder traits have shown some correlation with milk speed. If trying to select for milk speed, fore udder, rear udder and udder tilt are the single udder traits that have the highest correlation with milking speed, according to a study done at the University of Guelph.

Perhaps the most influence on milking speed is the timing of milking procedures. Improper timing of milking procedures can delay milk letdown and impact milk flow. Prep lag time should be between 90 and 180 seconds, allowing the cow to reach a peak milking speed of 8-10 pounds per minute.

Though more research needs to be done in the economics of milk speed, producers have seen an increase in efficiency from using milking speed data. Milking system efficiency can be measured in milk per stall or cow throughput. In most systems, labor savings will be the main driver in increasing cow throughput efficiency.