An experiment was carried out to determine the genetic variation in litter traits and reproductive intervals between different parities in New Zealand While (NZW) and Californian (CAL) rabbits. Data on 581 litters produced by 163 does mated to 43 bucks of IN7W and CAL rabbits were involved. A linear mixed model included the effects of service buck and does within service buck (as random effects) and year-season and parity (as fixed effects) was used for analysing such data. NZW breed had higher litter size, weight and gain along with a lower number of stillbirths and preweaning litter mortality relative to CAL breed. Reproductive intervals and number of services per conception of NZW rabbits were relatively lower than in CAL rabbits. Periods of reproductive intervals were short in both breeds (42-43 days from a kindling to another) and they are one of the encouraging factors for the effective use of these two standard breeds on a large scale of commercial production in Egypt. Phenotypic variaton in all litter trails and
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