1. Update on Structure EPD Development R. L. Weaber, J. Bormann, N
Update on Structure EPD Development R.L. Weaber, J. Bormann, N. Bello, B. Jensen, L. Giess, W. Fiske

2. Overview Introduction of feet and leg structure Materials and Methods
Results
Conclusion

3. Introduction Longevity can help offset the cost of replacements
Maintaining a mature cow herd which produces a higher percentage of calves balances the cost of replacement heifers (Cundiff, 1992)
A cow takes 6 years to repay her capital investment above depreciation value (Brooks, 2015)

4. Heritability in Dairy cattle
Foot angle to 0.13
Rear leg side view to 0.23
Rear leg rear view to 0.11
Composite Score to 0.41
(Vollema and Groen 1997, Onyiro and Brotherstone 2008, Laursen et al. 2009, and Wright et al. 2012)

5. Feet and Legs in the Dairy Industry
Moderate genetic relationships with type traits and longevity and functional longevity (Dekkers et al. 1994)
Udder conformation
Feet and leg structure
Longevity tends to be lowly heritable (Vollema and Groen, 1997)

6. Feet and Legs in the Beef Industry
Australian Angus Cattle
Investigate genetic parameters for feet and leg traits
Differences between linear and threshold modeling
(Jeyaruban et al., 2012)

7. Feet and Leg Traits in Beef Cattle
Australian Angus Association is currently publishing 5 structural soundness Estimated Breeding Values (EBVs).
Front Foot Angle
Front Claw Shape
Rear Foot Angle
Rear Leg Side View
Rear Leg Rear View
(Australian Angus Association, 2017)

8. Results Heritability Traits Linear Front Angle 0.32 Front Claw 0.33
Rear Angle
0.29
Rear Claw
0.17
Rear Leg Rear View
Rear Leg Side View
0.21
Jeyaruban et al. (2012)

9. Feet and Leg Traits in Beef Cattle
No genetic evaluations on feet and leg traits are currently being published in the United States
American Angus Association is asking breeders to collect and submit phenotypes
Foot Angle
Claw Shape

10. Feet and leg structure evaluation at K-State
Estimate genetic parameters for feet and leg structure in Red Angus (and Simmental) cattle
Investigate relationships within feet and leg structure traits and between feet and leg structure and production traits

11. Traits Measured
1,885 Red Angus cattle were subjectively scored on 14 traits including:
Body Condition Score (BCS)
Front Hoof Angle (FHA)
Front Heel Depth (FHD)
Front Claw Shape (FCS)
Front Side View (FSV)
Front View Knee Orientation (KNEE)
Front View Hoof Orientation (FHO)
Rear Hoof Angle (RHA)
Rear Heel Depth (RHD)
Rear Claw Shape (RCS)
Size of Hoof (SIZE)
Rear Leg Side View (RLSV)
Rear Leg Rear View (RV)
Composite Score (COMP)

12. KSU feet and leg scoring system

13. KSU feet and leg scoring system

14. KSU feet and leg scoring system

15. KSU feet and leg scoring system

16. KSU feet and leg scoring system

17. KSU feet and leg scoring system

18. KSU feet and leg scoring system

19. KSU feet and leg scoring system

20. KSU feet and leg scoring system

21. KSU feet and leg scoring system

22. Material and Methods
Every animal must be scored by at least two trained evaluators
Scores for each animal were averaged to reduce scorer bias
All animals included in the evaluation must have a registration number with Red Angus Association of America

23. Materials and Methods
1,720 animals included in the evaluation after edits
3 generation pedigree file was acquired from the Red Angus Association of America
13,306 animals
3157 sires, 1282 sires of sires, and sire of dams
8724 dams, 5913 dam of dams, and 2249 dam of sires

24. 1,217 females
503 males

25. Mean
56.6
St Dev
4.57
Mean
57.2
St Dev
4.55
Mean
59.69
St Dev
5.73

26. Distribution of Claw Shape
Mean
57.5
St Dev
6.43
Mean
52.76
St Dev
5.76

27. Results
Mean
46.04
St Dev
3.66

28. Mean
55.78
St Dev
4.95
Mean
53.71
St Dev
2.97

29. Results
Mean
31.37
St Dev
4.04

30. Linear Animal Model
ASREML (Ver 3.0 and 4.0, VSN International, LTD., Hemel Hempstead, UK)
(Co) Variance components and correlations
169 bi-variate models
Consensus (mean) estimates of additive and residual variances for informative bi-variate models
EPDs from Front and Rear Limb models for all animals in pedigree

31. Variance Components
Residual, genetic, and phenotypic variances were averaged between all combinations of 13 traits in bivariate analysis’s
Heritability for each trait was calculated from the mean of the variance components
𝒉 𝟐 = 𝝈 𝒂 𝟐 𝝈 𝒑 𝟐

32. Average Standard Error
Trait
Average Heritability
Average Standard Error
Body Condition Score
0.11
0.04
Front Hoof Angle
0.20
0.06
Front Heel Depth
0.17
0.05
Front Claw Shape
0.09
Rear Hoof Angle
0.19
Rear Heel Depth
0.25
Rear Claw Shape
Size of Hoof
0.36
Front Side View
0.16
Knee Orientation
Front Hoof View
Rear Side View
0.30
Rear View
0.14
Composite Score
0.12

33. Genetic (red; above diagonal) Phenotypic (purple; below diagonal) Correlations
Trait
BCS
FHA
FHD
FCS
RHA
RHD
RCS
Size
FSV
Knee
FHO
RSV RV
Comp
0.27
0.25
0.20
0.26
0.51
0.28
0.08
-0.04
0.24
0.19
0.40
0.38
-0.68
-0.70
-0.27
0.22
-0.26
0.07
0.29
-0.03
0.026
0.89
0.06
-0.21
0.88
0.85
0.09
-0.17
0.11
0.18
0.46
-0.05
0.23
-0.25
0.63
0.15
0.36
-0.33
-0.02
0.025
0.82
0.01
-0.31
0.10
0.94
-0.12
-0.06
0.45
0.05
-0.20
0.17
-0.36
0.03
0.13
0.75
0.12
-0.01
-0.13
0.31
0.02
0.47
0.14
0.86
-0.09
0.004
0.21
-0.24
0.72
-0.44
0.52
0.83
-0.23
0.16
0.56
-0.57
-0.11
0.41
-0.003
0.04
0.32
-0.59
-0.75
-0.07
-0.10
0.87
0.95
-0.38
-0.14
0.73
-0.46
0.002
-0.40
-0.64
-0.15
-0.30
-0.28
-0.32 1 2 3 4

34. Genetic and Phenotypic Correlations
Trait
BCS
FHA
FHD
FCS
RHA
RHD
RCS
Body Condition Score
0.27
0.25
0.20
0.26
0.51
0.28
0.08
-0.04
0.24
0.19
Front Hoof Angle
-0.03
0.026
0.89*
0.06
-0.21
0.88*
0.85*
0.09
-0.17
0.22
Front Heel Depth
-0.02
0.025
0.82*
0.01
-0.31
0.10
0.94*
-0.12
Front Claw Shape
0.05
0.10*
0.03
0.13
-0.05
0.75*
0.17
Rear Hoof Angle
-0.01
0.51*
0.02
0.47*
0.14*
0.86*
-0.09
0.23
Rear Heel Depth
0.46*
0.52*
0.12*
0.83*
0.11
0.21
Rear Claw Shape
0.38*
0.18*
FHA and FHD Strong correlations
FHA, FHD strong genetic corr with RHA and RHD
FCS and RCS low phenotypic corr; strong genetic corr.

35. Genetic and Phenotypic Correlations
Trait
Size of Hoof
Front Side View
Knee Orientation
Front Hoof Orientation
Rear Side View
Rear View
Composite Score
Body Condition Score
0.40*
0.19
0.38
0.25
-0.68*
0.26
-0.70*
0.24
-0.27
0.22
-0.26
0.07
0.29
Front Hoof Angle
0.11
0.18
0.46*
-0.05
0.23
-0.25
0.63*
0.15
0.36*
-0.33
Front Heel Depth
-0.06
0.45*
0.05
-0.20
0.51*
0.17
-0.36
Front Claw Shape
0.20
0.08
0.28
0.12
-0.01
-0.13
0.31
Rear Hoof Angle
0.004
0.21
-0.04
-0.24
0.72*
-0.44*
Rear Heel Depth
-0.23
0.16
0.01
0.56*
-0.57*
Rear Claw Shape
-0.11
0.03
0.41*
-0.36*
0.14
Front limb angles modest correlation with FHA and FHD
Rear limb angles modest genetic corr with RHA and RHD
Limb angles good indicator traits for hoof attributes

36. Genetic and Phenotypic Correlations
Trait
Body Condition Score
Front Hoof Angle
Front Heel Depth
Front Claw Shape
Rear Hoof Angle
Rear Heel Depth
Rear Claw Shape
Size of Hoof
0.23*
0.025
-0.003
0.03
-0.05
0.04
0.01
-0.03
0.02
Front Side View
0.13*
0.07*
0.05
0.08*
-0.02
Knee Orientation
-0.11*
0.11*
Front Hoof Orientation
-0.14*
0.12*
Rear Side View
-0.12*
0.026
0.16*
0.06
0.15*
0.002
0.24*
Rear View
0.10*
0.19*
0.21*
Composite Score
-0.15*
-0.20*
-0.30*
-0.21*
-0.23*
-0.28*
RHA and RHD low phenotypic correlations with limb angles

37. Genetic and Phenotypic Correlations
Trait
SIZE
FSV
KNEE
FHO
RSV RV
COMP
Size of Hoof
0.11
0.18
0.06
0.19
0.17
0.03
0.16
-0.17
0.32
Front Side View
0.02
-0.59*
0.21
-0.75*
-0.07
0.20
-0.10
0.24
0.87*
Knee Orientation
-0.11*
-0.13*
0.95*
0.07
-0.38*
0.23
0.26
Front Hoof Orientation
-0.24*
0.73*
0.01
-0.46*
-0.25
0.27
Rear Side View
-0.01
0.09*
0.10*
0.08*
0.31
-0.40
Rear View
-0.10*
0.21*
0.23*
0.32*
-0.64*
Composite Score
0.25*
0.38*
-0.07*
-0.09*
-0.06*
-0.32*
KNEE, FHO and FSV modest to strong genetic correlations
Low (and some negative) genetic correlations between front and rear limb angles

38. Conclusion Feet and leg traits have low to moderate heritability;
Useful indicator trait data obtainable from limb information via genetic correlations
If selection pressure is place on these traits genetic change can be realized

39. Any Questions? Thank you for listening!