Different genetic parameters for weaning weight and wool traits were estimated using restricted maximum likelihood (REML) in Angora rabbits. Total wool yield of first (I), second (II) and third (III) clips were taken as a separate trait under study. The records from more than 2,700 animals were analysed through fitting six animal models with various combinations of direct and maternal effects. A log likelihood ratio test was used to select the most appropriate model for each trait. Direct heritability estimates for the wool traits were found to be moderate to high across different models. Heritability estimates obtained from the best model were 0.24, 0.22, 0.20 and 0.21 for weaning weight, clip I, II and III; respectively. Maternal effects especially due to permanent environment had higher importance at clip I and found to be declining in subsequent clips. The estimates of repeatability of doe effect on wool traits were 0.44, 0.26 and 0.18 for clip I, II and III; respectively. Weaning weight had moderately high genetic correlations with clip I (0.57) and II (0.45), but very low (0.11) with clip III. Results indicated that genetic improvement for wool yield in Angora rabbit is possible through direct selection. Further, weaning weight could be considered as desirable trait for earliest indirect selection for wool yield in view of its high genetic correlation with wool traits.

Genetic parameters of growth traits were estimated in the German Angora rabbit reared in the sub-temperate region of India. Estimates of (co)variance components were obtained for body weights at weaning (42 days) and post-weaning at 84, 126 and 168 days. A total of 8,324 animal records were used for the analysis of these traits. The data were analyzed by restricted maximum likelihood (REML) fitting six animal models with various combinations of direct and maternal effects. A log likelihood ratio test was used to select the most appropriate univariate model for each trait. Direct heritability estimates were observed to be moderate for the traits under study. Heritability estimates for weaning (42 d), 84, 126 and 168 d weights obtained from the best models were 0.25±0.05, 0.17±0.05, 0.21±0.06 and 0.12±0.05. Maternal effects had higher importance at weaning, and declined with the advancement of age. Significant maternal permanent environmental effect on weaning and post-weaning weights was a carryover effect of maternal influences during pre-weaning age. The estimated repeatabilities of doe effects on body weights were 0.37, 0.22, 0.18 and 0.28 at weaning, 84, 126 and 168 d body weight, respectively. Results indicated that modest rate of genetic progress is possible for body weight traits of Angora rabbit through selection. Similarly, these growth traits could be included in selection criteria along with wool traits for early selection of the animals.

This study aimed to assess the effect of genetic and non-genetic factors on growth, wool yield and wool characteristics of German Angora rabbit. Data was collected on 607 adult rabbits over a period of four years (2018-2021). The least squares means of body weights (g) at various ages, wool yield (g) at I, II, III and IV clip and wool characteristics assessed by staple length (cm) and fiber diameter (μ) were estimated. Sires of the rabbit progenies demonstrated highly significant effect (P<0.01) on the studied traits except wool characteristics. Sex of the rabbits had significant effect on body weight at 10th, 12th, 14th, 16th, 24th weeks of ages and wool yield at III clip, with greater estimates of females than the males for III clip, staple length, and 24th weeks body weight. Winter and autumn seasons were the most favourable seasons in comparison to summer season for estimated traits. Winter born kits had the highest body weights of 683±20.1, 961±24.3, 1263±27.5, 1484±34.0, 1735±37.1, 1942±40.1, 2136±36.9, 2232±36.7, 2341±37.4 and 2429±37.4 g and the summer born kits had the lowest body weights of 588±22.0, 820±27.2, 1037±31.2, 1307±38.0, 1515.79±41.0, 1696±44.1, 1847±41.4, 1920±41.0, 2034±42.4 and 2139±41.6 g, at biweekly interval from 6th to 24th, respectively. Rabbits with litter size less than six performed better in comparison to other groups for all growth traits and wool yield at I and III clip. The heritability estimates were found positive and high in magnitude for all growth traits, moderate for wool clip at different clips and very low for staple length. Genetic and phenotypic correlations were found to be very high and significant among growth traits and low to moderate among wool traits. The study revealed scope for further improvement in growth and wool yield by adopting selective breeding in the colony.

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