# Presentation: 660836

## Properties of International Longevity Evaluations and Correlations with Other Traits 

## Longevity Challenges

**Improve the exchanged statistical parameters**
**Match EDC and heritability to better reflect reliability from different models**
**Are trait definitions consistent?**
**Correlations of longevity with other traits on each nation’s scale**
**Adjustment for yield traits**
**Genetic trends (correlation with birth year)**

## Effective Daughter Contributions

**1 EDC = 1 daughter if no censoring**
**EDC should be reduced for recent birth years due to censoring**
**Use number of culled daughters, or**
**Use squared correlation of partial with final longevity (DEU, ISR, USA), or**
**Use multi-trait EDC formulas for partial longevity traits (CAN and NZL)**

## Problems in Defining EDC

**With binomial traits, observed daughters should contribute EDC, not just culled daughters**
**If daughters had opportunity to be culled but none were culled yet, EDC should be > 0**
**Accurate EDC are more important for traits with low REL**

## Heritabilities

**Wide range (.02 to .20)**
**Genetic correlations and SD may be sensitive to incorrect estimates**
**Single-trait vs multi-trait EDC formulas across lactations (CAN, NZL)**
**Log scale (DEU) vs observed scale. Is transformation to observed scale accurate?**

## Data

**Bulls born 1985-1994 in MACE longevity file (van der Linde and de Jong, 2002)**
**Only data on “home country” scale (country with the most daughters)**
**Yield, SCS, and conformation evaluations from Interbull (Feb 2002)**
**Some scales reversed to make positive always desirable for longevity and undesirable for SCS**

## Correlations of Direct Longevity with SCS and Conformation

|  | Country (INTERBULL code) |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Trait | CAN | DNK | FRA | DEU | ISR | ITA | NZL | SWE | CHE | NLD | USA |
| SCS | -.27 | -.28 | -.35 | -.31 | -.22 | -.17 | - | -.26 | -.46 | -.27 | -.30 |
| Overall Udder  | .28 | .41 | .40 | .22 | - | .14 | -.26 | .23 | .36 | .34 | .26 |
| Udder depth | .25 | .43 | .39 | .26 | - | .27 | - | .34 | .37 | .35 | .28 |
| Foot Angle | .18 | .09 | .07 | .09 | - | .07 | - | .04 | .06 | .13 | .13 |
| Stature | .02 | .16 | .08 | -.02 | - | -.08 | -.47 | .06 | .14 | -.01 | -.07 |

## Correlations of Direct Longevity with Yield Traits

|  | Country (INTERBULL code) |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Trait | CAN | DNK | FRA | DEU | ISR | ITA | NZL | SWE | CHE | NLD | USA |
| Milk | .09 | .06 | .26 | .10 | .51 | -.22 | -.18 | .19 | -.04 | .11 | .25 |
| Fat | -.01 | .10 | .11 | .07 | .30 | -.15 | .28 | .13 | -.08 | -.17 | .19 |
| Protein | .03 | .09 | .17 | .11 | .51 | -.27 | .02 | .15 | -.04 | .04 | .27 |
| Birth Year | .10 | .36 | .26 | .07 | .24 | -.11 | -.01 | .08 | .09 | .14 | .19 |
| Combined Longevity | .86 | 1.00 | .95 | .93 | 1.00 | .98 | 1.00 | .99 | 1.00 | .98 | .97 |

## Percentage of 2nd Crop Bulls

|  |  | % of second-crop bulls in: |  |  |
| --- | --- | --- | --- | --- |
| Country |  Bulls | All Bulls | Top 50 | Bottom 50 |
| Canada (CAN) | 3501 | 8 | 34 | 12 |
| Denmark (DNK) | 3593 | 4 | 42 | 2 |
| France (FRA) | 6774 | 8 | 50 | 2 |
| Germany (DEU) | 6847 | 13 | 88 | 76 |
| Israel (ISR) | 440 | 10 | 12 | 2 |
| Italy (ITA) | 2751 | 13 | 16 | 30 |
| New Zealand (NZL) | 2579 | 15 | 0 | 32 |
| Sweden (SWE) | 907 | 13 | 62 | 22 |
| Switzerland (CHE) | 360 | 18 | 40 | 8 |
| The Netherlands (NLD) | 4622 | 10 | 36 | 6 |
| United States (USA) | 13,571 | 7 | 32 | 20 |

## Conclusions

**Correlations of longevity with SCS and conformation traits were fairly uniform across countries**
**Yield correlations with functional and with true longevity both varied across countries**
**Improved definitions of EDC and heritability are suggested**