A tot-V of 2257 bunnies of New Zealand White (NZW) and 1748 of Californian (CAL) weaned rabbits were used to evaluate genetically the growth performance of these two exotic breeds raised in adverse environment. Postweaning body weights at 5, 6, 8, 10 and 12 weeks and livability at the intervals of 5-6, 6-8, 8-10 and JO-12 weeks were studied Variance components and heritabilities (122) were estimated. Breeding values for growth traits were also estimated for sires and paternal granddams using an animal model. Heritabilities in CAL rabbits were generally higher than those in NEW. Estimates of h2 in .NZTV ranged from 0.228 to 0.718 for body weights and fron 0.002 to 0.112 for livability. while the respective estimates in CAL ranged from 0.266 to 0.552 and from 0.055 to 0.177. The ranges in estimates of sire breeding values (SRI') for body weights at 5, 6, 8, 10 and 12 weeks of age were 161, 111.4, 134.4, 419,8 and 660 grams in N.ZW rabbits and 216.1, 181.4, 213.5, 415.2 and 465.4 grams in CAL rabbits, respectively. For livability, the ranges in SBV were 2.0, 15.8, 3.6 and 0.8% at 6, 8, 10 and 12 weeks of age in NZPV and 7.6, 25.2 and 8.2% at 6, 8 and 12 weeks in CAL reibbits, respectively. Generally ranges in estimates of JOY recorded by CAL rabbits were relatively higher than those recorded by INTZW rabbits for most body weights, while the reverse trend was observed for livability Ranges in estimates of breeding values for paternal granddarns were lower than those obtained for sires themselves for most traits.
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