Divergent selection for fleece weight in French Angora rabbits: Non-genetic effects, genetic parameters and response to selection

In order to explore genetic variability of wool production and other quantitative traits, an 8-cohort divergent selection experiment for total fleece weight (TFW) was carried out in French Angora rabbits. Studies were made on the wool production of 669 female rabbits born between 1994 and 2001 and having produced wool from the third to 12th harvests. The aim of the selection experiment was to obtain two divergent lines (low and high) on total fleece weight. The studied traits included total fleece weight, weight of the two qualities of wool (WAJ1 and WAW1), homogeneity (HOM), live body weight at ages of 4 (LW4), 8 (LW8), 12 (LW12), 16 (LW16), and 20 (LW20) weeks and then 9 weeks before each harvest (9LW). A preliminary analysis of non-genetic factors was done with the GLM procedure. The genetic parameters and genetic trends were analysed using a BLUP animal model. Heritability estimates for TFW, WAJ1, WAW1, HOM, LW4, LW8, LW12, LW16, LW20 and 9LW were 0.38, 0.30, 0.10, 0.06, 0.30, 0.09, 0.14, 0.32, 0.39 and 0.45, respectively. Genetic and phenotypic correlations between TFW and WAJ1 were high (0.98 ± 0.01 and 0.89 ± 0.01, respectively). There was a low genetic correlation between TFW and 9LW (0.26 ± 0.12). After eight cohorts of selection, the divergence between the lines was approximately three genetic standard deviations. Selection for total fleece weight had a generally beneficial effect on fleece quality.