From old school dairy breeders telling you, “They are all worthless!” to geneticists telling you “They are the greatest thing since sliced bread!” it can be challenging to figure out whether tools like TPI® and LPI have significant merits in your breeding or marketing program
What Are They?
To get a better understanding of what each of these indexes represent start with the fact that TPI® (Total Performance Index) and LPI (Lifetime Profit Index) are multi-trait indexes. They both combine production, type, and health and fertility traits to rank sires on their ability to transmit an economic balance of these traits. TPI® is calculated by Holstein USA and LPI is calculated by The Canadian Dairy Network.
The big thing to remember about both of these indexes is that they are more or less a predictor of a bull’s ability to transmit based on established weightings. For TPI® that weighting is as follows
Source: Holstein USA, click on image for more details
Whereas LPI has the following weighting, 51% production, 29% conformation and 20% health traits. As you will notice, LPI actually puts a greater weighting on conformation and health than does the TPI®.
They’re Tools You Fool
The big thing to remember is both of these indexes were created to help identify superior sires that combined high production, sound conformation, and desirable health and fertility traits. It does not mean that these sires are the only sires you should be using. Or that if you only use these sires you will have the best herd in the world.
What it does mean is that you can use these tools to help short list what sires you are wanting to use, assuming that you are breeding for high production, conformation, and fertility. If you are like some old school breeders who feel that high lactation production is not worth the tradeoff then fine, LPI and TPI® are not for you. In reality, each breeding program would be best to develop their own index based on the needs and goals of their breeding program. Maybe you would want more emphasis on health or type. It all depends on your goals and then you work from there.
It’s All About the Marketing
Were these indexes created just for marketing? No. Were they created for ways to compare and sell sires? Yes. What’s the difference? Well when both these indexes were created they had all the right intentions. They were created for a way to compare sires on their overall genetic merits. Which lead to major sale and marketing opportunities for those organizations and breeders who had the top sires.
I can remember that, before these multi-trait indexes were introduced, everyone claimed to have the #1 sire or cow. While that is still happening, for the most part TPI® and LPI provide the opportunity for breeders to gain a clear understanding of who is the top sire for producing high production, sound conformation, and healthy cattle.
The Bullvine Bottom Line
With so many different traits that are evaluated, trying to identify which sires have the overall best genetics can be very challenging. While the TPI® and LPI formulas may not be the exact weighting that works for your breeding program, they are designed to represent that average breeder (if there is such a thing). They are designed to give opportunity to compare sires on relative merits and see which sires rise to the top. The big thing to remember is that they are to be used as tools! If you lose focus on that, these tools can have you looking like a fool!
I understand they are tools and only tools. The problem I have is the PL formula. Yes, it’s a formula and not a trait! I don’t really have a problem that PL formula is too confusing, but that it has way too much influence on TPI and NM. It makes the credibility of TPI and NM very low to me*. Big money in having a top 10 bull for world wide marketing/sales and I wouldn’t and don’t have a solution (yet) on how to rank bulls correctly….