Grossman M, Bohren B B
J Hered. 1985 Nov-Dec;76(6):459-62. doi: 10.1093/oxfordjournals.jhered.a110145.
Parameters of the logistic function of growth, fit to individual body weight curves of two randombred control populations of each sex of chickens from hatching to 45 weeks of age, were evaluated. Growth-rate constant and age at the infection point in the curve were estimated by the method of sample quantiles from individual weekly body weights of 225 males and 281 females of the Rhode Island Red (RIR) line, and 164 males and 239 females of the White Leghorn (WL) line. Heritability estimates, based on correlation among full-sibs, of growth rate constant were 0.18 +/- 0.32 in males and 0.29 +/- 0.29 in females of the RIR line, and 0.41 +/- 0.40 in males and 0.46 +/- 0.32 in females of the WL line. Estimates of heritability of age at the inflection point were 0.36 +/- 0.44 in males and 0.42 +/- 0.32 in females of the RIR line, and 0.46 +/- 0.41 in males and 0.50 +/- 0.28 in females of the WL line. Observed variation for each trait probably does not provide evidence for heritable differences. No genetic correlations were evident among growth-rate constant, age at the point of inflection, and initial or maximum weight. According to these results, it does not appear that selection for growth-rate constant or age at the point of inflection will change the shape of the growth curve of these populations genetically. Moreover, correlated genetic change in initial or maximum weight would not be expected.
评估了逻辑斯蒂生长函数的参数，该函数拟合了从孵化到45周龄的两个随机繁殖对照鸡群（每种性别各一个群体）的个体体重曲线。通过样本分位数法，根据罗德岛红（RIR）品系的225只雄性和281只雌性以及白来航（WL）品系的164只雄性和239只雌性的每周个体体重，估计了生长速率常数和曲线中感染点的年龄。基于全同胞间相关性的生长速率常数遗传力估计值，在RIR品系雄性中为0.18±0.32，雌性中为0.29±0.29；在WL品系雄性中为0.41±0.40，雌性中为0.46±0.32。拐点年龄的遗传力估计值，在RIR品系雄性中为0.36±0.44，雌性中为0.42±0.32；在WL品系雄性中为0.46±0.41，雌性中为0.50±0.28。每个性状观察到的变异可能无法为遗传差异提供证据。生长速率常数、拐点年龄与初始体重或最大体重之间没有明显的遗传相关性。根据这些结果，似乎选择生长速率常数或拐点年龄不会在遗传上改变这些群体的生长曲线形状。此外，预计初始体重或最大体重不会发生相关的遗传变化。
