Indexes are important genetic selection tools. They combine all significant genetic traits into one package – and get producers away from setting minimum criteria for specific traits. That allows you to focus on creating a next generation of cows that are the right fit for your environment.
A global industry standard index like TPI has certainly helped dairy producers improve their herds. The one-size-fits all TPI index places 46% of the total weight on production traits, 28% on health and fertility traits and 26% on conformation traits.
However, an index like this assumes all farms face the same challenges within their herd. It assumes everyone has the same farm goals and milk markets. It simply serves as a general overview for a one-size-fits-all genetic plan.
Consider your goals
When you set your own, customized genetic plan, you can divide the weights as you see fit. To decide which production, health or conformation traits to include, consider your farm’s situation and future goals. How are you paid for milk? In a fluid milk market, you’ll likely put more emphasis on pounds of milk as compared to those who ship milk to a cheese plant. Are you expanding or at a stable herd size? If you’re looking to grow from within to expand your herd, you’ll want to put more emphasis on Productive Life and high fertility sires than the producers who are at a static herd size and able to cull voluntarily.
Your farm’s scenario is unique. With different goals, environments and situations, it’s evident there is no such thing as a one-size-fits-all index.
Make progress where it matters
Just 42 TPI points separate the 100th and 200th ranked genomic bulls on Holstein USA’s December 2017 Top 200 TPI list. Does a separation that small mean these bulls offer similar genetic benefits? Of course not!
To illustrate why, let’s compare three different genetic plan scenarios. One focuses on high production, one on high health, the other on high conformation. The tables below show the sires, traits and genetic averages for the top five Alta sires that meet each customized genetic plan. Notice the extreme amount of progress, and also the opportunity cost for using each particular index.
When high production is the goal, your genetic plan may be set with weights of 70% on production, 15% on health, and 15% on conformation. A team of bulls fitting that plan averages 2400 pounds PTAM and 171 pounds of combined fat and protein.
|High Production: 70-15-15||Milk||Protein||Fat||PL||DPR||SCS||PTAT||UDC||FLC||TPI|
When health is the focus, a 30% production, 60% health, 10% conformation genetic plan might make sense for you. That team of bulls delivers averages of +9.5 PL, +5.0 DPR and 2.75 SCS. That’s more than four points higher for DPR than the high production group! However, you give up nearly 1100 pounds of milk and 41 pounds of components to get those high health numbers.
|High Health: 30-60-10||Milk||Protein||Fat||PL||DPR||SCS||PTAT||UDC||FLC||TPI|
Lastly, if your genetic goal is to improve conformation, the team below provides an average 2.47 for PTA Type, 2.86 Udder Composite, and nearly two points for Foot & Leg Composite. With that much emphasis on the conformation traits, you’ll sacrifice on pounds of milk, fat and protein, and give up some productive life and fertility.
|High Conformation: 25-25-50||Milk||Protein||Fat||PL||DPR||SCS||PTAT||UDC||FLC||TPI|
Now, compare those different genetic plan averages side-by-side. You can see that a mere 38 points separate these groups on TPI average. However, the genetic values for the production, health and conformation traits are extremely different.
|High Production: 70-15-15||2400||79||92||6.3||0.8||2.96||1.95||2.01||0.93||2730|
|High Health: 30-60-10||1315||52||78||9.5||5||2.75||1.34||1.43||1.26||2760|
|High type: 25-25-50||1151||49||78||8.1||2.8||2.82||2.47||2.86||1.93||2768|
15 bulls in the Top 5
Most of the bulls above rank similarly for TPI. But not one bull appears in more than one of the customized genetic plan top-5 lists. With 15 bulls in the top five, it’s clear to see there’s no such thing as a perfect bull. There is, however a perfect genetic plan. It’s the one you customize for your farm to match your current situation and future goals.
Think back to the examples above. Think about TPI (46% production, 28% health, 26% conformation). If your main goal is to increase milk production in your herd, emphasizing too much on the health and conformation traits will mean you sacrifice pounds of milk and total components in the next generation of your herd.
Alternatively, maybe you really want to improve the longevity and fertility of your herd. In that case, an index that focuses on conformation will cost you 1.4 months of productive longevity and more than two points of pregnancy rate in the next generation!
Bringing it together
Sticking to an industry standard index like TPI could get you the best ranking bulls for that index only. But that index doesn’t necessarily match your needs. If you’re looking for a more focused approach, keep these points in mind to make the most progress toward your farm’s goals:
- There’s no such thing as a “one-size-fits-all” genetic index.
- Work with your trusted Alta advisor to set your own, unique, customized genetic plan. Consider your farm’s goals, future plans and milk market as you decide how much emphasis to place on the production, health and conformation traits.
- Maximize progress toward your genetic goals by using a group of the best sires to match your unique genetic plan.