Differential analysis on growth of FFRC strain common carp (Cyprinus carpio) selection families at various culture stages

To observe selective potential of Best Linear Unbiased Prediction (BLUP)family based continuing breeding in FFRC common carp (Cyprinus carpio), we measured the indices of body weight (BW) and body shape at differnent culture stages of C.carpio in the second generation continuing breeding families. The results show that the fish in fastest growing group had slow growth speed before four months, but BW reached the maximum after nine months. For body shape, the fish body thickness (BT)/body length (BL) increased with increasing BW, but body height(BH)/BL decreased with increasing BW, showing long body shape of FFRC common carp. And the survival rate during two overwintering periods was all above 94%. The results suggest that the BLUP family selection method is feasible for long-term C.carpio selection. Moreover, the principal components analysis indicates that the first principal component for four morphometric characteristics of C.carpio was BW. Then correlation analysis of BW at different growth stages reveals that the correlation coefficients for 9 months to 24 months, 14 months to 24 months and 21 months to 24 months were significantly different(P < 0.01), which were 0.851, 0.897 and 0.957, respectively. Therefore, early individual selection is worthy of try in continued breeding process of FFRC common carp.