1. Longevity and Fertility
PAUL VANRADEN
Animal Improvement Programs Laboratory
Agricultural Research Service, USDA, Beltsville, MD

2. History of Productive Life
January 1994 – Single-trait PL for bulls
July 1994 – Multi-trait PL at HA for all bulls
January 1995 – Base change of 0.9 months
January 1996 – Cow PL PTA’s first published
August 2000 – New multi-trait methods at USDA
August 2000 – Base change of 0.8 months
November 2000 – Genetic correlations reduced

3. PTA Productive Life Productive Life (PL) =
Total months in milk by seven years of age, including up to 10 months per lactation.
Multi-trait PL includes correlated traits
Milk, fat, protein
SCS
Type composites (udder, feet & legs, size)
Cull rate gradually replaces correlated traits

4. Calculation of Multi-trait PL
PTA PL = PA PL + Cov(true PL – PA, PTA – PA) Var -1(PTA – PA) (PTA – PA)
Begin with PA, regress on PTA – PA
Direct (single trait) PL and 7 indirect traits included in vectors
Weight on PTA – PA for each trait is determined by correlations, heritabilities, and reliabilities
Decline to zero as single-trait REL for PL approaches 99%

5. Heritabilities and Correlations
Milk
Fat
Protein PL
SCS
Size
Udder
F&L
.30
.65
.90
.29
.20
.01
-.20
-.02
.77
.76
.26
.93
.82
.34
.085
-.40
-.04
.19
-.10
-.30
.10
-.11
-.33
.06
.03
.40
.22
.08
.27
.15
Genetic Correlation above diagonal
Heritabilities on the diagonal (for Holsteins)
Phenotypic Correlation below diagonal

6. Example Data for PL PTA REL % 81 61 66 75 71 67 PA -.4 RELPAb % 48 46
Milk (lb)
Fat (lb)
Protein (lb)
PLa (mo)
SCS
Size
Udder
F&L
PTA
+1,947
+61
+1.1
+3.38
+.52
+.90
+.99
REL % 81 61 66 75 71 67 PA
+588
+44
+28
-.4
+3.31
+.73
+.56
+.81
RELPAb % 48 46 47
aPTA is single trait, PA is multi-trait
bRELPA max = 50%

7. Example Weights for PL PTA REL % 81 61 66 75 71 67 PA -.4 RELPAb % 48
Milk (lb)
Fat (lb)
Protein (lb)
PLa (mo)
SCS
Size
Udder
F&L
PTA
+1,947
+61
+1.1
+3.38
+.52
+.90
+.99
REL % 81 61 66 75 71 67 PA
+588
+44
+28
-.4
+3.31
+.73
+.56
+.81
RELPAb % 48 46 47
Relative wt. % 3 4 5 54 -5 -8 16
Multi-Trait PTA
+1.4
RELMT % 63
aPTA is single trait, PA is multi-trait
bRELPA max = 50%

8. Stability of PL Evaluations
Update of 1997 study by Ryan Starkenburg
August 2001 evaluations compared for:
January 1995 active AI bulls
February 1997 active AI bulls
PTA protein adjusted to true protein
Bulls with sample code ‘0’ excluded
August 2001 PL reliability  90%
Regressions (expected to be 1)
Correlations (hoped to be high)

9. High PTA PL Bulls from 1995 PL 19951 PL 20012 PTA PL Bull Daus REL
C-E Bell Jake
103
.72
8461
.99
3.4
2.8
P-R Roebuck 50
.63
21,282
2.0
E S-W-D Eagle
10,823
13,542
3.3
2.5
B-H MarkOPolo
538
.86
11,520
3.2
2.3
B Ethan 39
.57
9687
3.0
1.4
V-V Cleitus Bert 42
.56
12,956
2.9
L-B Abel
3013
.98
1.2
J Secret Kody 28
.48
1410
.96
1.1
1January 1995 Evaluation
2August 2001 Evaluation

10. Low PTA PL Bulls from 1995 PL 19951 PL 20012 PTA PL Bull Daus REL
P Ijon Dakota
2817
.94
4086
.99
-2.0
-4.0
BigAlLouRahls 47
.53
809
-1.3
-0.5
M Enhanc. Tater 49
.57
650
.92
-1.1
-3.5
W-R Chalet-Red
131
.73
3346
.98
-1.0
-1.2
S Ijon Vision 86
.68
1363
.96
-0.9
-1.4
L-Ro-D Reid
120
1124
-0.8
R Rotate Jimmy 66
.62
706
O Rambo
199
.66
1839
-0.6
0.0
1January 1995 Evaluation
2August 2001 Evaluation

11. High PTA PL Bulls from 1997 PL 19971 PL 20012 PTA PL Bull Daus REL
E Meadowlord 73 65
932 93
3.4
1.0
R-VU Emperor 64 63
7016 99
3.3
2.6
SFL Sndwtr Itm 97 66
2396
3.2
2.8
Ked Juror 80 68
9766
1.1
I-C B Troy Cash 71 67
1348 95
3.1
Prices Bonus 54
5142
1.2
H-B Clei Aspen 56
1154 94
1.9
H Aristides 87 69
10,428
3.0
2.0
1February 1997 Evaluation
2August 2001 Evaluation

12. Low PTA PL Bulls from 1997 PL 19971 PL 20012 PTA PL Bull Daus REL
M-B C Geoffry 64
3299 98
-1.4
-1.8
Peticote Lance
1803 95
22,298 99
-1.2
-3.1
S-B N-B Mascot
10,460
31,021
-1.0
-2.7
Q-P Madison
320 81
637 92
-2.8
L Rex Richard
117 74
6581
-0.9
-1.5
J Rotate Jed
429 85
8951
-0.8
-0.7
P Desperado
621 89
1027 94
-0.6
-1.1
R Rte Juggler
2249 96
13,486
-1.7
1February 1997 Evaluation
2August 2001 Evaluation

13. Current and Past Evaluations Regressions and Correlations
August 2001 Regressions
Milk
Fat
Protein PL
SCS
February 1997
.90
.93
.85
.88
.94
January 1995
.92
.87
.96
August 2001 Correlations
.81
.86
.82
.62
.83
.78
.58
.80

14. PL and Lifespan Defined
Credit for maximum 10 mo per lactation
Records  305d weren’t stored in database
Long calving intervals unprofitable
Lifespan
Credit for months between lactations
Higher yield and bST allow longer lactations
Embryo donors not penalized

15. Lifespan and PL Compared
Heritability
6.7% for lifespan
7.6% for PL
(8.5% official PL estimate since 1994)
Genetic correlations of lifespan
.986 with PL
More correlated than PL with yield
Less correlated than PL with SCS
Less correlated with fertility (-.46 vs -.59)

16. Cow Fertility Days Open Calving interval – 280 days
Lower limit of 50 days, upper limit 250
Sold for reproductive problems = 250
Genetic parameters
3.7% heritability
.32 correlation with protein
.30 correlation with SCS

17. Bulls with Low Daughter Fertility
PTA Days Open
PTA PL
P Lance
15.9
-3.0
J Rte Jed
11.1
-0.6
K-M Bell Joy
11.0
-0.5
E Rte Duke
10.9
-1.4
R Rte Juggler
9.7
-1.7
J-S Mark Anthony
9.5
-1.8
H Mr Mark Cinder
9.0
-0.1
A-R Ever-Ready
8.0
-0.7

18. Bulls with High Daughter Fertility
PTA Days Open
PTA PL
E C Valiant
-7.2
1.2
S Mark Arthur
-6.0
3.4
O Chrmn Monitor
-5.4
0.4
S Valiant Winken
-5.3
0.7
T-H Valiant Rockie
-5.2
0.9
C-W Valour
-5.1
1.5
C Emerald Target
-5.0
1.6
L-M Centurian
-4.8

19. Foreign Longevity Evaluations
Measures of longevity:
Survival, herd life, stayability, durability, PL
Most countries adjust for yield
Evaluated in 13 Countries:
Australia, Austria, Canada, Denmark, France, Germany, Great Britain, Israel, Italy, Netherlands, New Zealand, Sweden, Switzerland, USA

20. Foreign Bull Productive Life
Options
Set PL equal to zero or breed average
Simple regressions on yield ( )
Use parent average from domestic PL data (August 2000)
Combine PA with Interbull yield and type (November 2000)
Include also Interbull SCS (May 2001)
MACE for longevity (Dutch research)

21. Conclusions
Longevity rankings have high value but lower accuracy than other traits.
Cow fertility has low heritability (3.7%) but high genetic correlation with PL (-.59).
Selection on PL is effective, but cow fertility evaluations could increase lifetime profit. Credit for embryo donors may be needed.