Bohren B B, Carson J R, Rogler J C
Genetics. 1981 Feb;97(2):443-56. doi: 10.1093/genetics/97.2.443.
Cornell Control White Leghorn chicks were grown in a common environment to five weeks of age and selected for fast and slow gain in body weight from five to nine weeks of age at two temperatures, 21.1 degrees (cold) and 32.2 degrees (hot), during which time a constant 50% relative humidity was maintained. All lines were tested each generation in both temperature environments. Selection continued for four generations, with a second replicate started six weeks after the first replicate in each generation. In the hot environment, a 20% reduction (104 g) in five-to-nine-week weight gain was found. The responses to selection for fast and slow growth were symmetrical except in the first generation, when an outbreak of bronchitis confounded selection for body weight with selection for disease resistance and allowed little gain in the slow lines. No genotype-by-environment interactions were found, indicating that selection in either direction in either selection temperature produced equal responses in either test temperature. This suggests that any interactions observed between the growth of strains in tropical vs. temperature climates must be due to some difference between these environments other than the temperature differences studied.
康奈尔对照白来航鸡雏鸡在共同环境中饲养至5周龄，然后在21.1摄氏度（寒冷）和32.2摄氏度（炎热）这两个温度下，从5周龄到9周龄根据体重增长快慢进行选择，在此期间保持相对湿度恒定为50%。所有品系在每一代都在两种温度环境下进行测试。选择持续了四代，在每一代中，第二个重复在第一个重复开始六周后启动。在炎热环境中，发现5至9周龄的体重增长减少了20%（104克）。除了第一代，对快速和缓慢生长选择的反应是对称的，第一代时支气管炎的爆发使体重选择与抗病性选择混淆，导致慢速品系几乎没有增长。未发现基因型与环境的相互作用，这表明在任何一种选择温度下向任何一个方向的选择在任何一种测试温度下都会产生相同的反应。这表明，在热带气候与温带气候下观察到的品系生长之间的任何相互作用，一定是由于这些环境之间除了所研究的温度差异之外的某些差异所致。
