ABSTRACT

Data from 363 kitten obtained over period of 9 months (June, 2002 — March, 2003) from the mating of ten bucks and forty — four breeding does consisting of thirty Dutch and fourteen New Zealand White does and five bucks each of New Zealand White and Dutch breeds of rabbit were used to provide estimates of genetic and phenotypic parameters as well as prediction equations for growth traits at 3, 6, 9 and 12 weeks of age. Traits measured were individual body weight (lBW), ear length (EL), body width (BW), body length (BL), head to shoulder (HS), shoulder to tail (ST) and length of leg (LL). High heritability estimates (h2 ) of 0.43 ± 0.35 (6 weeks), 0.45 ± 0.35 (9 weeks), 0.59 ± 0.48 (9 weeks), 0.43 ± 0.19 (9 weeks), 0.67 ± 0.45 (12 weeks) were obtained for IBW, HS, ST, LL and HS, respectively. Moderate estimates of 0.30 ± 0.30 (9 weeks), 0.36 ± 0.35 (12 weeks) and 0.35 ± 0.35 (12 weeks) occurred for BW, IBW and BL, respectively. EL (6 weeks), BW (6 weeks), BL (9 weeks), IBW (9 weeks), BL (12 weeks) and ST (12 weeks) had low heritability estimates (h2 ) of 0.11 ± 0.21, 0.14 +0.24, 0.18 ± 0.25, 0.11 ± 0.22, 0.09 ± 0.34 and 0.06 ± 0.23, respectively. Heritability estimates obtained from both MHS and FS correlations were high in all cases. The moderate to high heritability estimates suggests possible improvement of these traits by either pedigree or individual selection methods. High repeatability estimates were obtained for IBW (0.62), BL (0.69) and LL (0.69) at 6 weeks of age while estimates for other traits at 6, 9 and 12 weeks of age were low. The relative genetic gain per generation expected from selection for repeated records as compared with one record obtained in this study suggest that weighing and measuring 8 - 10 rabbits would provide a satisfactory evaluation of the inherent 6-week body weight and all linear measurement traits. This is expected to give above 16% greater genetic gain than measuring one rabbit. Genetic and phenotypic correlations were moderate to high and positive among traits examined at all stages of growth except for -0.12 and —0.01 values obtained for genetic correlations between IBW and HS and IBW and BL, respectively. These correlations among the traits were generally in the expected direction. As a result of the generally high and positive correlations between body weight and linear body parameters it was possible to predict body weight of live rabbits from linear body measurements, as an aid to farmers in areas where sensitive scales are not available. BL followed by ST and BW were the best predictors of body weight in live rabbits.