Data on 14210 litters of New Zealand White rabbits produced by 2945 does mothered by 1613 dams were analysed to compute variance components and her itabilities of lifetime production traits. These traits included total number born (TNB), total number born alive (TNBA), tom] number weaned (TNW), and length of lifetime production (LT). For animals with and without records, transmitting abilities (PTA) for these traits were predicted using single-trait (SAM) and multi-traits (MAM) animal models taking into account the relationship coefficient matrix among animals (A4). Heritability for LT was low (0.09), while the estimates for litter-size traits (i.e. TNB, TNBA and TNW) were moderate and ranged from 0.16 to 0.21. For the list of all dams with records, the ranges in estimates of PTA obtained by the MATO vs SAM were 20.6 vs 11.8 bunnies for TNB, 21.08 vs 10,8 bunnies for TNBA, 11,3 vs 7.1 bunnies for TNW and 1.01 vs 0.82 month for LT. The percentages of claim with positive values of PTA obtained by the MANI vs those obtained by the SAM were 97.4 vs 48.2% for TNB, 97.3 vs 49.2 % for TNBA, 99.4 vs 50.8% for TNW and 87.2 vs 50.9% for LT. Percentages of darns ivith records common between the SAM and MANI procedures were moderate or high and ranged from 53.1 to 69,0%. The percentages of dams remaining in the same position when using the two models were almost equal to zero. Estimates of PTA for animals without records showed the same trend obtained for animals with records.. The positive estimates obtained for maternal grand-dams ranged from 44.2 to 47.7% when using the SAM vs 60.3 to 87.1% when using the MAM, while the respective estimates recorded for maternal grand-sires ranged from 43.2 to 45.9% and from 68.6 to 92.4%. Most correlations among ranks of PTA estimated by the SAM and those estimated by the MANI were relatively moderate or low.
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