Latimer B E, Brisbin I L
Department of Poultry Science, Aiken, SC 29801.
Growth. 1987 Winter;51(4):411-24.
Growth and mortality responses were recorded for 541 chicks, representing five different breeds of chickens, following acute exposures to gamma radiation stress at two days of age. Although there were no statistically significant differences in the LD50/30 of the five breeds studied, Cobb broilers showed the highest (1580R) and White Leghorn bantams the lowest (980R) levels, respectively. Other breeds studied included the standard White Leghorn, Athens Randombreds and a strain of feral bantam. Growth rates of body weights were proportionately more depressed by radiation stress than were body sizes, as measured by the lengths of the culmen, tarsus, middle toe and longest primary wing feather of all 32 day-old survivors. Among these structures, the length of the culmen seemed to be the least affected by radiation stress in all of the breeds studied. Feral bantams were able to tolerate the greatest depression in weight gain before exhibiting mortality at exposures below their LD50/30' while Cobb broilers tolerated the greatest depression of weight gain at higher exposure levels. There was a suggestion that those characteristics which were strongly selected for in the course of a particular breed's development were those which experienced the greatest proportional depressions following exposure to gamma radiation stress.
对541只雏鸡（代表5个不同品种的鸡）在2日龄时急性暴露于伽马辐射应激后，记录其生长和死亡率反应。虽然所研究的5个品种的半数致死剂量（LD50/30）没有统计学上的显著差异，但科布肉鸡显示出最高水平（1580伦琴），而白来航矮脚鸡则显示出最低水平（980伦琴）。其他研究的品种包括标准白来航鸡、雅典随机交配鸡和一种野生矮脚鸡品系。体重的生长率受辐射应激的抑制程度比身体大小更成比例，身体大小通过所有32日龄存活鸡的喙长、跗跖长、中趾长和最长的初级飞羽长度来衡量。在这些结构中，喙长在所有研究品种中似乎受辐射应激的影响最小。野生矮脚鸡在暴露于低于其LD50/30的剂量下出现死亡之前，能够耐受体重增加的最大程度下降，而科布肉鸡在较高暴露水平下耐受体重增加的最大程度下降。有一种观点认为，在特定品种的发育过程中被强烈选择的那些特征，是在暴露于伽马辐射应激后经历最大比例下降的特征。
