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Direct and maternal additive effects and heterosis in prolificacy weaning traits in rabbits
Three complete diallel crossbreeding trials were realized between 1968 and 2005 involving 5915 weaning records of four rabbit breeds (California, Chinchilla, New Zealand and Semigiant White) to determine direct and maternal additive effects and heterosis in prolificacy traits at weaning in rabbits: proportion of litters weaned, number weaned and viability. Genetic effect estimations were done applying linear contrasts after Dickerson (1969) model. Maternal additive effects were more important than direct effects and ratify the superiority of New Zealand breed. Direct additive effects were favorable for the Californian and Chinchilla breeds. Heterosis averaged 10.0, 8.8, and 13.0% for the three traits resp. and was significant and positive in 61% of the analysis. Maximum heterosis (13-17%) was found for the reciprocal pair of crosses: NS, CCh, ChS and CS. Results avail simple crossing as a rapid and effective way of genetic improvement for suboptimal conditions.
Keywords:
rabbits, prolificacy, diallel cross
