Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh Original cung cấp cho các bạn kiến thức về sinh học đề tài:Phenotypic plasticity of body pigmentation in Drosophila: for single major genes influencing fat androstenone level and development of bulbo-urethral glands in young boars. | 357 Genet Sei Evol 1997 29 357-366 Elsevier Inra Original article Support for single major genes influencing fat androstenone level and development of bulbo-urethral glands in young boars MN Fouilloux1 p Le Roy1 J Gruand2 c Renard3 p Sellier1 M Bonneau 4 1 Station de génétique quantitative et appliquée Institut national de la recherche agronomique 78352 Jouy-en-Josas cedex 2 Station experimentale de selection porcine Institut national de la recherche agronomique 86480 Rouillé 3 Laboratoire de radiobiologie appliquée Institut national de la recherche agronomique -Commissariat à 1 énergie atomique 78352 Jouy-en-Josas cedex 4 Station de recherches porcines Institut national de la recherche agronomique 35590 Saint-Gilles France Received 21 April 1997 accepted 5 June 1997 Summary - A two-step genetic analysis was performed on data collected in a four-generation selection experiment comprising a control and a selected line in a Large White-Landrace crossbred population. The two-trait selection index used for choosing replacement boars of the selected line included fat androstenone level and the average thickness of right and left bulbo-urethral glands the latter trait being an indicator of the sexual maturity status of young boars. Fat androstenone level was determined on a biopsy sample of backfat taken at 118 kg liveweight whereas bulbo-urethral gland size was measured by echotomography using a rectal probe at 99 kg liveweight. A total of 949 entire males from 57 sires and 353 dams were recorded for both traits. In the first step of analysis REML genetic parameters were estimated using a bivariate animal model. Heritability estimates SE were for fat androstenone level and for bulbo-urethral gland size. A fairly close genetic correlation was found between the two traits. The second step of analysis consisted in testing the hypothesis of a mixed mode of inheritance polygenes major gene for each trait using segregation analysis methods. A .
