With April proofs comes the introduction of JPI 2017 to replace the previous JPI 2015.
Jersey Performance Index™ (JPI™) is the American Jersey Cattle Association’s (AJCA) strategy for increasing lifetime net income.
The AJCA took into account the following three key fundamentals for Jersey sustainability while determining JPI 2017. These fundamentals were determined by a Capper and Cady 2012 study comparing the environmental impact of Jersey and Holstein milk for cheese production.
- Increase production
- Maintain body size
- Maintain or improve components
What is the purpose of the new JPI 2017?
- Increase milk production
- Improve the density of milk
- Moderate body weight
- Improve herd life, fertility, udder health, and functional conformation
What new traits have been added to the formula?
- CFP Milk
- Every 100 pounds of PTA milk needs 8.8 pounds combined fat and protein
- Pounds of Milk = CFP/0.088
- CFP Milk = PTA Milk – Pounds of Milk
- If CFP Milk is positive, the JPI™ value is negative because there is more water than components
- Body Weight Composite (BWC)
- Proxy for feed efficiency, and replaces body size composite
- PTA Cow Livability
- Measures a cow’s ability to stay alive on the farm
What is the impact of JPI 2017?
- Significant drops in JPI for all industry sires.
- The upper JPI threshold will drop from about 300 JPI to 230 JPI, and all industry bulls will drop in their JPI value.
- Significant rescaling, similar to a base change.
- We see genomic sires JPI™ values fall 38 points on average
- Some re-ranking – in both directions
- Some minor and some significant
Here is a full breakdown of the new JPI 2017. In the simplest terms, JPI 2017 has five percent less weight on production and five percent more weight on type traits as compared to JPI 2015. But there’s more to it than that. The following traits are new additions to the JPI 2017 formula.
|JPI 2015||JPI 2017|
|PRODUCTION TOTAL WEIGHT||58||53|
|Somatic cell score||6||6|
|Daughter pregnancy rate||7||7|
|Cow conception rate||2||2|
|Heifer conception rate||2||2|
|HEALTH TOTAL WEIGHT||27||27|
|Rear udder height||1.9||1.8|
|Rear udder width||0.1||0.1|
|TYPE TOTAL WEIGHT||15||20|