PROGRESSIVE PERFORMANCE RANKING (introduced 2007)
The Brown Swiss Progressive Performance Ranking (PPR) is the ranking system for sire and cow genetic evaluations.
The formula has relative weights which add to 100 and, thus, are comparable to the percentage weight for each variable.
|
PPR Formula Relative Weights (Percentage)
|
| |
Protein |
Fat |
PL |
UDC |
MO |
DPR |
LIV |
SCS |
CCR |
HCR |
EFC |
| 2020 PPR |
30 |
22 |
8 |
10 |
6 |
16 |
4 |
4 |
|
|
|
| 2025 PPR |
26 |
26 |
8 |
10 |
6 |
8 |
4 |
4 |
4 |
2 |
2 |
The PPR Formula
D2025 [26(PTAprotein/SDprotein) + 26(PTAfat/SDfat) + 10(PTAUDC/SDUDC) + 8(PTADPR/SDDPR) + 8(PTAPL/SDPL)
+ 6(PTAMO/SDMO) + 4(PTALIV/SDLIV) - 4(PTASCS-3.06/SDSCS) + 4(PTACCR/SDCCR) + 2(PTAHCR/SDHCR) + 2(PTAEFC/SDEFC) ]
where:
UDC = Udder Composite (See Formula below)
DPR = Daughter Pregnancy Rating
PL = Productive Life
MO = Mobility
LIV = Livability
SCS = Somatic Cell Score
CCR = Cow Conception Rate
HCR = Heifer Conception Rate
EFC = Early First Calving
SD = Standard Deviation of corresponding traits follow:
| PPR Trait |
Standard Deviation (04/25) |
| Protein |
18.96 |
| Fat |
23.67 |
| UDC |
0.74 |
| DPR |
2.51 |
| PL |
2.65 |
| MO |
1.00 |
| LIV |
2.03 |
| SCS |
0.21 |
| CCR |
2.85 |
| HCR |
2.59 |
| EFC |
2.75 |
Since the weights sum to 100, the divisor is (100/100) or 1.
Udder Composite
UDC Formula:
(UDC) = .14(PTAFUA/SDFUA) + .22(PTARUH/SDRUH) + .22(PTARUW/SDRUW) + .16(PTAUC/SDUC)
+ .10(PTAUD/SDUD) + .08(PTAFTP/SDFTP) + .04(PTARTP/SDRTP) + .04(PTATL/SDTL)
Corresponding Standard Deviations
| UDC Trait |
Standard Deviation (04/25) |
| Fore Udder Attachment (FUA) |
1.0 |
| Rear Udder Height (RUH) |
0.9 |
| Rear Udder Width (RUW) |
0.8 |
| Udder Cleft (UC) |
0.8 |
| Udder Depth (UD) |
0.9 |
| Front Teat Placement (FTP) |
1.0 |
| Rear Teat Placement (RTP) |
1.0 |
| Teat Length (TL) |
1.3 |