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.