Crossbreeding experiment on Indonesian local rabbits: the heterosis effect on growth performance

The study aims to investigate the heterosis effect of crossing two imported rabbits with local rabbits on growth characteristics and performance using a nonlinear regression model. The study utilized three rabbit breeds: Flemish Giant rabbits (F), Rex rabbits (R), and Indonesian local rabbits (L). Selective breeding consisted of three breeds: F (FF), R (RR), and L (LL). Two crosses were formed between the male ancestors of L and the respective female ancestors of F (LF) and R (LR). Each offspring's body weight (BW) was measured every 3 d starting from birth. FF exhibited the highest BW among purebred animals. The LF crossbreed had a greater estimated mature weight compared with purebred animals. The predicted mature live weight of the asymptotic value for LR animals was higher than for LL rabbits but lower than for RR rabbits. The heterosis effect was lower when crossing L and F animals compared with crossing L and R animals. The average heterosis impact values were 4.68 for LF and 15.32 for LR. LF rabbits showed superior heterosis effects when the growth parameter and inflection point were determined using a logistic model. This study emphasizes the use of strategic breeding to optimize rabbit growth and performance by offering detailed insights into growth dynamics and heterosis effects in different crossbreeding situations.