Along with August 2025 sire evaluations, CDCB released a brand-new milking speed trait. The following FAQs outline everything you need to know about this trait.
What does the new Milking Speed trait measure?
Abbreviated as MSPD, the new Milking Speed trait measures pounds of milk per minute.
How is milking speed (MSPD) calculated?
Milking speed is calculated as the total pounds of milk in an individual milking divided by the total duration of milking, in minutes, for the given milking.
Where does the data come from?
The data for this evaluation comes from in-unit sensors in conventional milking systems from 11 different manufacturers. At this point, there is no data included from automated milking systems.
What details do you need to know about the Milking Speed (MSPD) trait?
- Average MSPD value for Holstein bulls: 7.1 pounds per minute
- Expected range in MSPD trait values: 6.2-8.1 pounds per minute
- To interpret the values, this means that daughters of a bull with an MSPD value of 8.1 pounds per minute are expected to have a faster milking time than the average population. Daughters of bulls with an MSPD value of 6.2 are expected to milk slower than the average population.
- MSPD Standard Deviation: 0.3 pounds per minute
- Heritability: 42%
- Reliability: 58% for genomic proven bulls, 67% for daughter-proven sires
- Breeds: calculated only for Holsteins at this point
- Ages: includes information for cows of all lactations, both complete and partial lactation records
Is Milking Speed correlated with any other traits?
Milking Speed (MSPD) is correlated at 0.43 with Somatic Cell Score (SCS), which means that faster milking speeds are associated with a higher somatic cell score.
MSPD is also correlated at -0.28 with Mastitis Resistance (MAST), which means that faster milking speeds are correlated with less resistance to mastitis.
How is this different than other milking speed traits?
If you’re used to looking at Milking Speed data from Alta, then you’ve been seeing the Canadian Milking Speed trait published by Lactanet. That trait will continue to be published based on subjective, producer-reported milking speeds to identify first lactation cows as average or fast.
Find more information about other milking speed evaluations HERE under the Definition of the Milking Speed trait on the CDCB website.
What is the expected economic benefit?
While the data has not been quantified, and will vary from one farm to another, herds using MSPD for genetic selection can expect improved parlor efficiency and potential improvement in herd uniformity for milking times.
Will MSPD be included in the NM$ index?
Initially, MSPD will not be incorporated into NM$, but it could be added in the future. MSPD is lowly correlated with NM$, which suggests it is not already captured in NM$ through other traits.
Why select for milking speed and not milking duration?
Milking duration does not account for the amount of milk produced, making it a less useful metric.
Does the MSPD evaluation include data from automated milking systems?
At this time, MSPD does not include milking speed data from robotic milking systems. Data utilized to calculate the trait is collected from in-line sensors in traditional parlor equipment.
What data was used to research this trait?
According to CDCB, geneticists at CDCB and USDA Animal Genomics and Improvement Laboratory (AGIL) worked with raw milking parlor data from 304 herds. This data set consisted of milk weights, milking durations, breed, parity, and meter manufacturer (OEM).
After data cleaning, the final dataset used in the research and development of MSPD represented 165 herds, nine milk meter manufacturers, and 47,833 complete lactations of 43,788 Holstein and Jersey cows, including 12,237 genotyped cows. All available phenotype data used in the computation of MSPD lactation records was from complete lactations only. While the initial dataset included automated milking system (AMS) data, it was not included in the final dataset. Inclusion of this data will be investigated as research continues.
How is data from different equipment manufacturers handled?
Because data for this evaluation was captured from 11 different parlor equipment manufacturers, there was a distinction made within the Milking Speed Format 8 data file to identify what type of system was used to collect the data. Since each manufacturer has a unique way to measure the factors included in MSPD, the data is standardized for use in genetic evaluations.
What does the future of this trait look like?
As more data becomes available, MSPD evaluations may be provided for additional breeds.
Since MSPD does not account for automatic milking systems, CDCB will investigate the data collection and evaluation potential for those systems going forward.
How should you use this information?
When it comes to new genetic traits, it’s important to consider your farm’s milk payment situation and management system. We invite you to work with a trusted Alta advisor to determine whether a trait like MSPD should fit within your customized genetic plan.
