Agricultural Research Service, University of Georgia, Athens, USA.
Theor Appl Genet. 1978 May;52(3):105-11. doi: 10.1007/BF00264742.
Individual phenotypic selection for high 4 week body weight was conducted for 40 generations in two lines of Japanese quail under two protein environments. Line P was selected on an adequate 28% protein diet, and line T was selected on a 20% protein diet containing 0.2% thiouracil (TU). In generation 20, a subline R was established by subjecting progeny from the T line to a 20% protein diet; in generation 27, a subline S was developed by subjecting progeny from the T line to a 28% protein diet containing 0.2% TU. Progeny from a nonselected control line (C) were reared with selected lines and sublines in all generations.Quail in the P line continued to respond to selection for 40 generations; body weights increased from 90 to approximately 200 g. Mean body weights of T line quail peaked in generation 22 and did not appear to show any definite gains thereafter. Body weight responses of sublines R and S were greater than those in the T line and indicate that changing the selection environment following long-term selection may be an effective technique to maximize total selection responses for 4-week body weight in quail. Realized heritability estimates for 4-week body weight were larger in the P line than in the T line in all comparisons. Realized estimates were high (30-45%) for the ten generations 1-10; moderate (15-20%) for generations 11-30, and small (5-10%) for generations 31-40.
在两种蛋白质环境下，对两条日本鹌鹑品系进行了 40 代个体表型选择，以获得 4 周龄体重高。P 系在 28%的充足蛋白质饮食上进行选择，T 系在含有 0.2%硫尿嘧啶 (TU) 的 20%蛋白质饮食上进行选择。在第 20 代，通过对 T 系后代进行 20%蛋白质饮食的处理，建立了一个亚系 R；在第 27 代，通过对 T 系后代进行含有 0.2% TU 的 28%蛋白质饮食的处理，开发了一个亚系 S。在所有世代中，从非选择对照系 (C) 获得的后代与选择系和亚系一起饲养。P 系的鹌鹑继续对选择做出反应 40 代；体重从 90 克增加到大约 200 克。T 系鹌鹑的体重在第 22 代达到峰值，此后似乎没有出现任何明确的增长。亚系 R 和 S 的体重反应大于 T 系，表明在长期选择后改变选择环境可能是最大限度提高鹌鹑 4 周龄体重总选择反应的有效技术。在所有比较中，P 系的 4 周龄体重实际遗传力估计值均大于 T 系。在第 1-10 代的 10 个世代中，实际估计值较高（30-45%）；在第 11-30 代，中等（15-20%）；在第 31-40 代，较小（5-10%）。
