Across country evaluation of clinical mastitis and somatic cell count by multitrait model
Enyew Negussie*, Minna Koivula and Esa Mäntysaari
MTT Agrifood Research, Jokioinen, Finland*[email protected]
55th Annual Meeting of the EAAP, Bled, Slovenia, September 5th – 9th, 2004
Session G2.9: Breeding schemes and functional genetics – Free comunications
Background
8 Rapid genetic progress in milk yield
8 Increased interest in udder health
8 Strategies vary across countries
420August 2004
418August 2003
418August 2002412August 2001
CMSCC
No. of countries Evaluation Year
Countries participated in interbull evaluation for udder health
source: http://www-interbull.slu.se/udder/
Nordic countries
8National recording for health data in dairy
8Clinical mastitis in breeding programs
8 Genetic link - Joint evaluation
Nordic countries
Nordic cooperation
Joint testing and evaluation
8 joint testing and use of AI bulls
8 accurate comparison and selection
8 efficient utilisation of resources
SCC - CM
8 Reasons for culling – single trait model biased
8 Indicators of different aspects of udder health
8 CM – info. from correlated trait important
8 Breeding goal- subsequent lactations needed
Objective
Test multitrait model for joint genetic evaluation of bulls for udder health traits
Source of dataFinland and Sweden
SCC
Lactation mean of log transformed (logescc) test-day somatic cell count (in 1000/ml)
CM”0” / ”1”
Veterinary records/culling due to udder diseases within 7days before and 150 days after calving
Trait definition
Description of the data set
10,38111,280
4358---
6060---
Bulls in pedigree- With daughters- Total
1-31-31-3Lactations
JointSwedenFinland
4,42,12,2Records (mill.)
2,21,01,1Cows (mill.)
11.210.6cm3
8.88.6cm2
7.38.2cm1
CM (%)4.43(1.1)4.39(0.9)scc3
4.14(1.0)4.38(0.9)scc2
3.97(0.9)4.37(0.9)scc1
SCC
SwedenFinlandMean
Mean SCC and CM by lactation
Joint across country model
Residual
Sire
HY
YM x Country
HY5
Calv age x Parity x Country
MT-MP sire model (scc+cm)
Random effects
Fixed effects
0.0220.9550.7590.6870.6960.577cm3
0.0200.8680.6810.7040.654cm2
0.0230.5770.6640.721cm1
0.1190.9810.811scc3
0.1220.899 scc2
0.137scc1
cm3cm2cm1scc3scc2scc1Traits
Heritability and genetic correlations of SCC and CM in the 1st, 2nd and 3rd lactations
Results
I. Univariate vs. Multivariate
Correlation between EBV’s from joint multitrait and joint univariate model
0.8670.8650.8640.9980.9960.996330Young(1995-97)
0.9060.9240.9240.9980.9980.998660Old(1991- 93)
cm3cm2cm1scc3scc2scc1
CMSCC
Traits
No. Bulls
Group of bulls
5CM2
19SCC1
No. of common bulls in the top 20
18SCC3
16SCC2
7
9CM1
CM3
Traits
Ranking top bulls: No. bulls common with the univariate model
CMSCCCMSCC
0.7460.8430.6110.841>200
0.6880.7500.6510.740101-200
0.6740.6400.6010.63520-100
MultivariateUnivariate
Models
Daughters per sire
Correlations between EBVs from randomly split data sets
Genetic trend for CM from joint multivariate(bcm)Vs univariate (ucm) model
-0.02
-0.015
-0.01
-0.005
0
0.005
0.01
0.015
0.02
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
Birth year
Eb
v-cm
bcm ucm
Results
II. Across country vs. within country model
Correlations between EBVs from joint across country Vs. within country models
0.980.980.990.950.960.96215(1995-97)
0.970.980.990.970.970.98338(1991- 93)FINLAND
SWEDEN
Country
0.970.970.970.970.980.99219(1995-97)
0.990.990.990.990.990.99329(1991- 93)
cm3cm2cm1scc3scc2scc1
CMSCC
Traits
No. Bulls
Group of bulls
-0.02
-0.015
-0.01
-0.005
0
0.005
0.01
0.015
0.02
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
Birth year
Eb
v-cm
jcm fcm
Finnish within country vs. joint across country model for CM
-0.02
-0.015
-0.01
-0.0050
0.005
0.01
0.015
0.02
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
Birth year
Ebv-
cm
jcm secm
Swedish within country vs. joint across country model for CM
Conclusions
¤ More accutrate prediction of EBVs for CM from MT model.
¤ MT model stable for predicting breeding value solutions in future records of animals.
¤ Good agreement between the joint andnational models.
