1. Selection differences and –intensity Chapter 8: Selection response

2. Selection response Selection difference Selection intensity Selection respons Heritability of threshold traits Breeding value for threshold traits Genetic correlation Changes in correlated traits

3. S = P S - P Selection difference, S

4. i = S/ s P Selection intensity, i

5. Selection intensity table

6. Selection response,  G individual selection R =  G = h 2 S = h 2 i  P = h i  A or  G = (I S – A)

7. Selection response,  G i = Selection intensity r AI = Accuracy  A = Additiv genetic standard error L = Generation interval

8. Extended formula for  G general formula

9. Threshold traits

10. Heritability estimates for threshold traits

11. Threshold traits scale problems

12. Threshold traits Distribution of hip dysplasia (HD) in German Shepherd dogs B1 and more normal, B2 and under HD

13. Threshold traits

14. Calculation of an index, I, for a threshold trait

15. Genetic correlation and change in secondary traits Pleiotropy Linkage

16. Example of negative genetic correlation A1A1 A2A2

17. Determination of genetic correlation by selection experiments r Ax,Ay =  G y /  Ay  G x /  Ax Correlated change in trait y by selection for trait x

18. The genetic correlation is dynamic

19. Correlation between fitness and selected traits

20. Genetic correlation: Examples

21. Back lash on a genetic level - maximal fitness

22. Auto selection for litter size