# Presentation: 143311

## Choice of Scales for Delivery of Genetic Evaluations to the Public

## Can We Harmonize Trait Scales?

**International marketing and education is  difficult because scales differ**
**Advertisements cross national borders**
**9 of 19 full-page bull advertisements contained only pictures, no numbers! *****(Holstein International, March, 2004)***** **
**Internet sites provide foreign evaluations **
**Joint data analyses could produce evaluations on a common scale**

## Time to Change Bases

**Every 5 years (2005, cows born in 2000)**
**18 of 25**** countries: AUS, BEL, CZE, DEU, ESP, EST, GBR, HUN, IRL, ISR, ITA, JPN, NLD, NZL, POL, SVN, USA, ZAF**
**At beginning of year?**
**Every year**
**6**** countries: CAN, CHE, FIN, FRA, NOR, SWE **
**At beginning of year except FRA=June**
**Each evaluation**
**1**** country: DNK**

## Previous USA Base Changes

| 1965 | Predicted Difference (subtract mean yield) |
| --- | --- |
| 1974 | Modified Contemporary Comparison |
| 1984 | Red & White and Holstein bases separated |
| 1989 | Red & White and Holstein bases merged, Animal Model |
| 1995 | Age-Parity adjustments (changed trend) |
| 2000 | Lifetime Net Merit, true protein (SD change)  |

## Possible Things To Do 

**Change mean and variance base**
**Change units and/or direction**
**Change evaluation models**
**Put different breeds on the same base**
**Submit to the Interbull test run**
**Prepare educational materials**

## Somatic Cell Count

**Measured with same standard metric unit (cells / ml) in every country**
**Transformed by log 2, log 10, or log e**
**Reversed scales in 9 of 19 countries**
**Added means of 100, 3, 4, etc.**
**Changed SD to report EBV, PTA, or STA**

***Different choice in almost every country!***

## Udder Health Scales

| Ctry | Unit | Mean | SD |  | Dir | Ctry | Unit | Mean | SD | Dir |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| USA | PTA | 3.1 |  | .22 | — | NLD | RBV | 100 | 4 | + |
| CAN | PTA | 3.0 |  | .25 | — | DNK | RBV | 100 | 5 | + |
| BEL | EBV | 3.0 |  | .47 | — | SWE | RBV | 100 | 7 | + |
| JPN | EBV | 2.4 |  | .42 | — | DEU | RBV | 100 | 12 | + |
| AUS | EBV | 0.0 |  | .11 | — | ITA | STA | 4 | 1 | + |
| GBR | PTA | 0.0 | 13 |  | — | FRA | STA | 0 | 1 | + |
| HUN | STA | 0.0 | 1 |  | — | ESP | STA | 0 | 1 | + |

## Longevity Scales

| Ctry | Unit | Mean | SD | Ctry | Unit | Mean | SD |
| --- | --- | --- | --- | --- | --- | --- | --- |
| GBR | PTA | 0 | 0.3 | NLD | RBV | 100 | 4.0 |
| CAN | PTA | 3 | 0.2 | DNK | RBV | 100 | 5.0 |
| USA | PTA | 0 | 1.7 | SWE | RBV | 100 | 10.0 |
| ISR | PTA | 0 | 7.0 | DEU | RBV | 100 | 8.0 |
| CHE | EBV | 0 | 4.1 | ITA | STA | 3 | 1.0 |
| AUS | EBV | 0 | 1.9 | FRA | STA | 0 | 1.0 |
| NZL | EBV | 0 | 11.0 | IRL | STA | 0 | 1.0 |

## Yield Trait Scales

**True protein in ****5 of 21**** countries:**
**AUS, FRA, HUN, POL, USA ****(as of 2000)**
**True% = Crude% —.19 ****(e.g. 3.00% vs 3.19%)**
**Protein yield (kg) reduced by 5 - 6%**
**Age-parity adjustments differ **
**16 of 25**** countries adjust to average parity**
**5**** adjust to mature, ****4**** adjust to 1****st**** parity**
**Separate lactation proofs available**
**2 scales (RBV and EBV) seems too much**

## Conformation Scales

**Standardized Genetic Merit (PTA ******** SD)**
**Mean = 0, SD = 1**
**9**** ****of 21**** countries: CHE, CZE, DNK, FRA, HUN, GBR, ITA, JPN, USA**
**Relative Breeding Values**
**Mean = 100, SD = 4, 7, 10, 12**
**8**** countries in northern Europe**
**PTA, EBV, or other ****(****4**** countries)**

## Selection Index Scales

**Units and SD not well documented**
**Top bull for total merit ****(February ‘04)**
**DNK 114, DEU 145, AUS 162, FRA 179**
**NZL 246, NLD 366, GBR 826 **
**USA 857 (NM), USA 1918 (TPI)**
**ESP 2148, CAN 2360, ITA 2944**
**Ranking on home scale may include traits not evaluated by Interbull**

## Conclusions

**Base and scale changes go together**
**Many countries plan to change in Feb 2005**
**Too many different scales cause confusion**
**Direction of udder health / SCS unclear**
**Recommended scales may help**
**Only 3 months until September test run**