A fresh, forward-thinking approach to udder selection is here. The Modern Udder Index (MUI) is redefining the approach to creating function, modern udders. It’s bringing a more practical and progressive strategy to today’s dairies.
Born from the need for a better measure of functional udders, MUI prioritizes the udder traits that matter most in today’s commercial Holstein herds. Phil Bachman, PEAK Global Product Specialist and a key contributor to the index’s creation, explains the need for a change:
“We know that strong udders are widespread within the industry, with minimal culling for udder problems or poor conformation. With that in mind, a progressive strategy for udder selection is now necessary.”
What Matters Most in Modern Udders
When looking through the lens of a modern dairy, the udder must perform three essential functions:
1. Efficient milk factory: Quickly replenish with large volumes of milk and stay healthy.
2. Secure, mobile storage: Safely store milk, avoid udder injury and stand the test of time.
3. Rapid, efficient milk release: Deposit milk quickly and completely with minimal human handling.
Lifetime performance favors cows with moderate udder depth and udder cleft as well as ideal teat traits (rear teat placement, front teat placement, teat length). While fore and rear udder traits (fore udder attachment, rear udder height, rear udder width) can yield positive lifetime performance, overemphasis can lead to less desirable teat placement and length.
“Industry composites for udders often deliver larger cows with less ideal parlor traits,” shares Bachman. This was a primary driver behind developing MUI.
Why MUI? The Modern Solution for Modern Cows
MUI is designed to promote lifetime production and longevity without selecting for larger cows. It achieves a balanced approach, yielding a “happy medium” for parlor traits – like teat placement and length. It also maintains center support while delivering steady progress in fore and rear udders.
At GENEX, we are proud to offer MUI values for all GENEX Holstein sires. We have also prioritized MUI within the GENEX ICC™ index, our proprietary genetic selection index.
Modern Udder Index (MUI) FAQs
The goal behind MUI is to maintain functional udder traits that impact parlor performance while advancing udder traits that contribute to lifetime production. MUI embraces two-way trait selection for five traits: udder depth, udder cleft, front teat placement, rear teat placement and teat length. In addition, it caps contribution from three additional traits: fore udder attachment, rear udder height and rear udder width. Furthermore, MUI successfully separates udder traits from stature (a major drawback of Udder Composite) while also delivering more functional parlor traits.
MUI is developed by PEAK using the eight udder traits measured and reported by Holstein Association USA, Inc. MUI is not with associated with any official industry indexes. Instead, it’s tailored specifically for genetic selection in modern, commercial dairies.
Two-way (or intermediate optimum) traits promote selection toward the population average and away from extreme values in either direction. Many of today’s conformation traits are examples of two-way traits where change is not desirable. Instead, average is the best outcome.
For certain traits, MUI applies positive selection pressure up to a certain level but does not reward extra value beyond that point that could hinder udder functionality. Research demonstrates added benefit from selection for fore udder attachment, rear udder height and rear udder width; however, extremes for these traits can negatively impact the functional, parlor traits.
Yes! Despite the high correlation between stature and many udder traits, MUI allows for strategic udder selection without the side effect of increased stature.
MUI offers a holistic view of functional modern udders. For best results, it should be considered within a broader selection index – like the GENEX ICC™ index – where multiple traits are weighted appropriately for the best long-term results. Talk with your GENEX representative today about potentially including MUI in your custom genetic plan.
