Table 4 Numbers of observations (N) and number of levels for fixed and random effects in models fitted to litter size (LS0), litter weight (LW0) and body mass traits at ages of 21, 42, 63 days and at mating (BM21, BM42, BM63, BMM). Fixed effects are generation number, linear regression on mother’s weight at mating, litter number and sex; random effects are additive genetic, litter and permanent environmental effects
TraitNGenerationWeight of MotherLitter NumberSexAdditive Genetic EffectLitter env.Permanent env.
LS05,911281214,4302,4201481
LW05,884281214,4102,3971474
BM2119,080291219,0804,362
BM4214,586291213,9593,132627
BM6313,910291213,2833,044627
BMM7,41628127,4162,626