1. Genetic solution to the problem of boar taint for production of entire males
P.K. Mathura,*, H.A. Mulderb , J. Ten Napelb, J. J. Windigb, R.E. Crumpb, B. van der Felsb , L. Heresc, S. Bloemhofa, M. S. Lopesa, E. F. Knola
a IPG, Institute for Pig Genetics B.V., The Netherlands
b Animal Breeding and Genomics Centre, Wageningen UR
c VION Food Group, The Netherlands

2. Genetic solution to the problem of boar taint
Detection methods
Human Nose Scores (HNS)
Androstenone and skatole
Genetic parameters
Production
Reproduction
Genomic analysis
Breeding strategy

3. Boar taint
Consumers recognise boar taint by SMELL
When pork is heated

4. So do the slaughter plants ..
Schnippe, Schweinzuch und Schweinemast, SUS, 4:2011

5. We did so in the “lab” Human Nose Scores (HNS) 4 3 2 1 21,972 samples
Strong boar taint
Boar taint
Weak boar taint
Deviant but not boar taint
Normal pork odour 3 2 1
21,972 samples
Source: Mathur et al. (2011) submitted to Meat Science journal

6. But the science believes in boar taint compounds
Accumulated in fat
Skatole (3-methyle-indole)
Produced in hind gut
Related “Fecal” odour
Androstenone (pheromone)
Produced in testes
Related “urine” odour

7. Genetic parameters More than 7,000 boars Trait And (ln) Ska P
(high Ska)
HNS
Androstenone (ln)
.54
.33
.31
.27
Skatole (ln)
.37
.41
.84
.36
P (High Skatole)
.96
.40
.35
Human Nose Score (HNS)
.65
.90
.93
.12
Heritabilities (diagonal), Genetic correlation (below diagonal), Phenotypic correlations (above diagonal). Significant estimates in bold
Source: Windig et al. (2011) submitted to Journal of Animal Science

8. Production traits Genetic correlations And (ln) Ska P (high Ska) HNS
Daily Gain
-.06
-.10
-.15
-.07
Fat depth
.17
.12
.13
.29
Loin depth
-.13
-.11
N= 7,336 : Androstenone and Skatole N= 20,130 : Human Nose Scores
Source: Windig et al. (2011) submitted to Journal of Animal Science

9. Reproduction traits Genetic correlations And (ln) Ska (ln) P
(high Ska)
HNS
Age at first insem. (d)
-.10
-.13
-.19
Gestation length (d)
.06
.05
.11
Weaning to inse. Int. (d)
-.09
-.06
-.11
Total number born (N)
-.07
-.04
.08
Still born ln(N+1)
.04
.02
Mortality (%)
.12
Significant estimates in bold

10. Genomic information
Reduction in boar taint due to a single SNP with large effect
Source: Duijvesteijn et al. BMC Genetics (2010)

11. We used a panel of SNPs
Each AI boar genotyped with a panel of boar taint related SNPs selected out of 60K SNPs

12. Genotypes based on selected SNP panel Genomic Breeding Values
Genomic selection
Phenotypic data
HNS,
And, Ska
Genotypes based on selected SNP panel
Genomic Breeding Values
(GBVs)

13. Breeding goal Reduce “True” Boar taint
Assumed to follow normal distribution
Values on underlying scale based on area under the curve

14. Sorting of LBT boars a) b) c) LBT = Low Boar Taint
ASI compounds (carcass and biopsy) b)
TOPIGS
LBT-boar
Human nose scores c)
LBT = Low Boar Taint
Genomics

15. Effect of genetic selection
Human Nose Scores
Effect of LBT boars (%) 4
Strong boar taint
Boar taint
Weak boar taint
Deviant but not boar taint
Normal pork odour
- 41%
- 40%
- 19%
- 8%
+ 5% 3 2 1

16. Boar taint can be reduced through genetics
Conclusion
through a combination of:
A) Boar taint compounds (And, Ska)
B) Human nose scores
C) Genomic information
Boar taint can be reduced through genetics

17. Thanks !