Select Sires

HERDLIFE BUILDERS
May 2003

Herdlife Builders™: A Practical Approach to Breeding for Longevity

Click here for a list of Herdlife Builders.

In a perfect world cows produce at high levels, produce valuable calves regularly and live long, productive lives. In the "real" world, we know that often cows don’t stay in the herd as long as people would like. And that can affect a herd’s profitability significantly.

So, what is it that can help cows last longer? Recently Dr. Kent Weigel reported on a study evaluating Holsteins that calved for the first time between 1992 and 1996. When looking for type traits that were highly correlated with longevity, he found that all udder traits as well as "rear legs, rear view" had a linear relationship with productive life. For example, cows with high fore-udder scores lasted more than a year longer than their low-scoring counterparts, and a similar pattern was seen for suspensory ligament. The relationship was even more pronounced for udder depth, with cows that scored 40 lasting from 12 to 18 months longer than cows scoring 10 on Holstein Association USA’s 50-point linear scale.

This is consistent with findings published by Holstein Association USA, which concluded that type conformation is an important factor in long-lived cows. Its research has shown that among all linear traits, udder depth and fore-udder attachment are the two most important traits for explaining longevity. In addition, bulls that sire cows that last also sire cows with better feet and legs.

In addition, the Association conducted a study on herdlife, which identified six important linear udder traits and their contribution to increased longevity in Holsteins (see Figure 1). It also has identified that selecting for superior mobility, steeper foot angle, wider rear-leg stance with little or no "hock in," and slightly straight rear legs (side view) results in longer-living offspring. Based on research, these traits have been combined into a single feet-and-legs composite (FLC) value for the convenience of producers.

Figure 1. Udder traits that help increase longevity. Holstein Association USA has developed the Udder Composite Index (UDC), using individual traits derived from the results of a research study on herdlife. This study shows the following weights accurately reflect each udder trait's contribution to increased longevity.

Udder depth	.30	Rear udder height	.16
Fore udder attachment	.16	Rear udder width	.12
Front teat placement	.16	Udder cleft	.10

Collectively this research supports what producers know: a long, productive life begins with well-attached udders, and correct feet and legs.

Identifying Bulls With Type that Leads to Longevity
Building on this research, geneticists at Select Sires looked at Predicted Transmitting Ability (PTA) data for all Holstein sires born since 1980, focusing on type traits and how they correlate with longevity. They found the numerical points at which feet-and-leg and udder traits began to help improve longevity, and looked to see whether there were additional traits that significantly affected herdlife.

The geneticists have translated this research into a practical, convenient way to identify bulls that are best able to sire longevity by developing a new breeding tool called "Herdlife Builders." This designation:

Includes only the top 50 percent of active-A.I. sires for udder composite, which incorporates all six linear udder traits;
Includes only the top 50 percent of active-A.I. sires for feet-and-legs composite, which includes all four linear traits evaluating feet and legs; and
Excludes the highest 10 percent of active-A.I. sires for dairy form, which has a negative correlation to longevity.

Choosing the Best Herdlife Builders for Your Herd
Recognizing that different operating environments call for different management and breeding strategies, we understand that you need to know more about Herdlife Builders to find the ones that are right for your dairy. That’s why you’ll find a summary of information about each of these 45 Herdlife Builders on the back of this flyer. Your professional Select Mating Service™ evaluator and sales representative can work with you to identify sires that will fit best in your program.

Backed by research and designed for use in the real world, Herdlife Builders can add longevity and profitability to your herd.

™Herdlife Builder and Select Mating Service are trademarks of Select Sires Inc.

Select Sires Inc., 11740 U.S. 42 North, Plain City, Ohio 43064 / Phone: (614) 873-4683 Fax: (614) 873-5751