View Full Table | Close Full ViewTable 1.

Hazard ratios comparing lines1 for overall lifetime survival or for survival ≤5 parities or >5 parities

 
Period
Ratio Overall ≤5 parities >5 parities
MH:MC 1.622 ± 0.13 3.492 ± 0.14 1.42 ± 0.19
ML:MC 2.002 ± 0.11 1.36 ± 0.36 2.582 ± 0.11
MH:ML 0.82 ± 0.17 2.572 ± 1.14 0.552 ± 0.15
1MH = high and ML = low heat loss selection; MC = unselected control.
2Indicates a hazard ratio significantly different from 1 (P < 0.05).



View Full Table | Close Full ViewTable 2.

Hazard ratios comparing lines1 for overall lifetime survival within each culling criteria

 
Culling criteria2
Ratio DI 0BA 0W 42BI LS FL
MH:MC 2.663 ± 0.18 3.86 ± 0.30 2.04 ± 0.45 1.47 ± 0.23 1.10 ± 0.29 1.30 ± 0.98
ML:MC 2.364 ± 0.21 2.00 ± 0.73 2.36 ± 0.37 1.21 ± 0.29 1.893 ± 0.17 2.55 ± 0.47
MH:ML 1.13 ± 0.47 1.94 ± 2.34 0.86 ± 0.68 1.22 ± 0.44 0.58 ± 0.20 0.51 ± 0.49
1MH = high and ML = low heat loss selection; MC = unselected control.
2DI = death or illness; 0BA = 2 consecutive litters with none born alive; 0W = 3 consecutive litters with none weaned; 42BI = birth interval longer than 42 d; LS = average of the most recent 2 litters was less than half the average of the first 3; FL = no first litter by 42 d cohabitation.
3Indicates a hazard ratio significantly different from 1 (P < 0.05).
4Indicates a hazard ratio with a tendency to be different from 1 (P < 0.10).



View Full Table | Close Full ViewTable 3.

Average number of parities by line1 assuming differing maximum number of parities allowed

 
Maximum MH MC ML
4 parities 2.395 2.466 2.461
6 parities 3.290 3.368 3.383
8 parities 4.153 4.282 4.193
10 parities 4.945 4.933 4.841
12 parities 5.583 5.710 5.431
1 yr 6.214 6.248 6.036
1MH = high and ML = low heat loss selection; MC = unselected control.