Elliptical selection experiment for the estimation of genetic parameters of the growth rate and feed conversion ratio in rabbits

• Published in: Journal of animal science Vol. 82; no. 3; pp. 654 - 660
• Main Authors: Piles, M, Gomez, E.A, Rafel, O, Ramon, J, Blasco, A
• Format: Journal Article
• Language: English
• Published: Savoy, IL Am Soc Animal Sci 01-03-2004; American Society of Animal Science
• Subjects: Animal Feed; Animal productions; Animals; Bayes Theorem; Biological and medical sciences; Body Weight - genetics; Breeding; Eating - genetics; Female; Fundamental and applied biological sciences. Psychology; Litter Size - genetics; Male; Models, Biological; Models, Genetic; Multivariate Analysis; Parity - genetics; Rabbits - genetics; Rabbits - growth & development; Rabbits - physiology; Selection, Genetic; Terrestrial animal productions; Vertebrates; Weight Gain; Parameter estimation; Elliptical Selection; Farming animal; Growth rate; Selection; Bayesian Theory; Rabbit; Genetic parameter; Lagomorpha; Feed conversion efficiency; Vertebrata; Meat animals; Mammalia; Genetic Parameters; Feed Conversion Ratio
• ISSN: 0021-8812; 1525-3163

Two elliptical selection experiments were performed in two contemporary sire lines of rabbits (C and R) in order to optimize the experimental design for estimating the genetic parameters of the growth rate (GR) and feed conversion ratio (FCR). Twelve males and 19 females from line C, and 13 males and 23 females from line R, were selected from an ellipse defined by a quadratic index based on these traits. Data from 160 rabbits of each of the parental generations of lines C and R and their offspring (275 and 266 animals, respectively) were used for the analysis. A Bayesian framework was adopted for inference. Marginal posterior distributions of the genetic parameters were obtained by Gibbs sampling. An animal model including batch, parity order, litter size, and common environmental litter effects was assumed. Posterior means (posterior standard deviations) for heritabilities of GR and FCR were estimated to be 0.31 (0.10) and 0.31 (0.10), respectively, in line C and 0.21 (0.08) and 0.25 (0.12) in line R. Posterior means of the proportion of the variance due to common litter environmental effects were 0.14 (0.06) and 0.21 (0.06) for GR and FCR, respectively, in line C and 0.17 (0.06) and 0.22 (0.06) in line R. Posterior means of genetic correlation between both traits were -0.49 (0.25) in line C and -0.47 (0.32) in line R, indicating that selection for GR was expected to result in a similar correlated response in FCR in both lines.