Holstein Association USA will implement an adjustment to the Total Performance Index® (TPI®) formula in conjunction with the official genetic evaluation run taking place in April 2021.
The Holstein Association USA Genetic Advancement Committee met in February 2021 to review current research and new traits that have been made available to the industry. Opportunities to enhance the TPI formula were identified, and recommendations were made to the Holstein Association USA board of directors, who recently voted to approve those recommendations.
The April 2021 change enhances HAUSA’s existing Feed Efficiency (FE$) formula by incorporating the new Feed Saved trait that was released in December 2020. The economic assumptions used in the formula have been updated to match the most current research done by USDA-AGIL.
Feed costs can make up over half of the total costs on a dairy farm and selecting for more feed-efficient cows can improve a farm’s bottom line. Genetic selection for feed efficiency supports our industry goals to reduce the overall environmental footprint associated with producing a gallon of milk.
The formula for FE$ starting in April 2021 will be:
($0.0008 x Milk) + ($1.55 x Fat) + ($1.73 x Protein) + ($0.11 x Feed Saved)
The first three components of this formula reflect the extra profit coming from cows producing more pounds of milk, fat, and protein. The additional feed costs required to produce an extra pound of milk, fat, and protein, have been subtracted from the income that farmers receive for their milk. Component prices, reflecting primarily a cheese market, have been updated. The trait Feed Saved includes information based upon HAUSA’s Body Weight Composite and new data on dry matter intake from CDCB. Every pound of feed saved returns a net profit of eleven cents per cow per lactation.
Dr. Tom Lawlor, Holstein Association USA Executive Director, Research & Development, points out that “a higher dollar value for the Feed Efficiency index reflects good feed utilization. It includes better utilization of the feed to produce extra pounds of milk, fat, and protein; feed saved from cows with a lower body weight and less maintenance costs; and feed saved from better feed conversion. This last part is known as residual feed intake (RFI), i.e., the difference in efficiency that we see between cows after accounting for the feed that goes into the maintenance of the cow and the production of milk.”
The improved Feed Efficiency Dollar index now includes three important contributors to net profit: improved production, controlling maintenance costs, and better feed conversion. As more information has been added to FE$, the difference between the lowest and the highest FE$ animals has expanded. The new TPI formula uses a slightly larger standard deviation for FE$, i.e., 52 versus 45.
The new April 2021 TPI formula:
Breeders should focus upon the overall selection indices, such as TPI, to select their top breeding animals and to cull the lower end animals. FE$ is like other sub-indices such as Body Weight Composite, Feed Saved, Fertility Index, and Health Index, in that, they help us to better understand how we are genetically changing our cows and which parts of the dairy enterprise have the largest impact on your bottom line.
Incorporating feed intake data into the feed efficiency equation provides a valuable piece of information. Of all the sub-indexes, FE$ has the highest correlation with overall total profit. Good feed utilization is the most important component of profitability on your farm.
For more information about the genetic evaluations, visit www.holsteinusa.com.