Fort D J, Stover E L, Lee C M, Adams W J
The Stover Group, Stillwater, OK 74076, USA.
Biol Trace Elem Res. 2000 Nov;77(2):159-72. doi: 10.1385/BTER:77:2:159.
The effect of copper (Cu) deficiency on the reproduction and development in Xenopus laevis was evaluated, culminating in the development of a defined concentration-response relationship. Separate groups of four adult frog pairs were fed one of three diets for 28 d: (1) low-copper (-Cu); (2) copper supplemented (+Cu); and (3) ASTM standard beef liver and lung (BLL). Embryos collected from frogs administered the -Cu diet had markedly decreased egg masses and viability rates and an increased rate of necrosis when compared to the other dietary treatments. Malformations in -Cu larvae included maldevelopment of the heart, eye, craniofacial region, brain, and notochord. Larvae from adults administered the -Cu diet showed delayed abnormal hindlimb development, characterized as selective reductive deficiencies distal to the femur, with poor cartilaginous development. A U-shaped dose-response curve characteristic of nutritional essentiality was developed for Cu. Overall, these studies indicated that embryos produced from frogs administered a -Cu diet are substantially less viable than embryos from frogs administered a +Cu or copper-adequate (BLL) diet.
评估了铜（Cu）缺乏对非洲爪蟾繁殖和发育的影响，最终建立了明确的浓度-反应关系。将四组成年蛙对分别喂食三种日粮中的一种，持续28天：（1）低铜（-Cu）；（2）补充铜（+Cu）；（3）美国材料与试验协会（ASTM）标准牛肉肝和肺（BLL）。与其他日粮处理相比，取自喂食-Cu日粮的青蛙的胚胎，其卵块和存活率显著降低，坏死率增加。-Cu幼虫的畸形包括心脏、眼睛、颅面部区域、大脑和脊索发育不良。来自喂食-Cu日粮的成年蛙的幼虫表现出后肢发育延迟异常，其特征为股骨远端选择性还原缺陷，软骨发育不良。针对铜建立了营养必需性特有的U形剂量-反应曲线。总体而言，这些研究表明，喂食-Cu日粮的青蛙所产生的胚胎，其活力远低于喂食+Cu或铜充足（BLL）日粮的青蛙所产生的胚胎。
