A closed-circuit continuous measurement system for metabolic rate and physioengineering study on thermoregulation of chick embryos.

(1)本文介绍了一种利用微机组成的耗氧量闭路连续测量系统。通过检测去除CO_2的CO_2吸收剂电导率的变化，同时测定胚胎产生的CO_2。(2)由于O_2、CO_2和热量都是通过蛋壳进行交换的，因此本研究首先从孵化开始的几个小时内改变蛋壳的气体传导率，研究其对气体交换、胚胎发育、血气和血液学指标的影响。(3)胚胎的气体交换器是卵壳内血管发达的绒毛尿囊膜。本文根据电路模型分析，用计算机绘制诺模图，研究了心输出量在胚胎和绒毛尿囊循环中的分布。血液流动在鸡蛋内部热流中的重要性是通过测量肝脏的冷却速率来评估的。 ...更多信息 ng，并在空气和氦氧混合气体中杀死鸡和鹌鹑蛋。(4)在鸡胚发育过程中，对鸡蛋冷却时的热损失和产热进行了定量评价。在此基础上，确定了冷却方法，并测定了发育期鸡胚的代谢反应。结果表明，鸡胚发育后期出现微弱的恒温代谢反应，体外吹打后这种反应增强。提示甲状腺激素和蛋壳气导在鸡孵化前体温调节发育中起重要作用。(5)在不同发育阶段的半早熟Brown Noddy胚胎中，还研究了对冷却的代谢反应。与早熟鸡相比，半早熟Noddy在孵化前没有明显的恒温反应。(6)结合胚胎体温调节的研究，进行了基础实验，旨在将本研究推进到阐明鸡胚胎发育循环功能的研究项目。少

(1) A closed-circuit continuous measurement system for oxygen consumption was developed utilizing a microcomputer. The carbon dioxide produced by an embryo was simultaneously measured by detecting the changes in electrical conductivity of the CO_2 absorber which was used to eliminate produced CO_2.(2) Because the O_2 CO_2 and the heat was exchanged through the eggshell, the effects of gas conductance of the eggshell on the gas exchange, embryonic development, blood gases and hematological variables were investigated first by changing it from the beginning of incubation on for several hours.(3) The gas exchanger of embryos is the chorioallantoic membrane which is well vascularized inside the eggshell. A distribution of the cardiac output to the embryo and the chorioallantoic circulation was studied based on a circuit model analysis and a nomogram drawn with an aid of computer. The importance of blood flow in an egg's internal flows of heat was evaluated by measuring coolng rates of livi … More ng and killed chicken and quail eggs in air and in helium-oxygen mixture.(4) The heat loss from eggs when cooling was quantitatively evaluated in developing chick embryos together with heat production. Referring to these data, wa determined the cooling methods and the metabolic response of developing chick embryos were measured. It was found that a feeble homeothermic metabolic response appears in the late chick embryos and it becomes stronger after external pipping. The thyroid hormones and the eggshell gas conductance were suggested to play an important role in thermoregulation developing before hatching in chickens.(5) The metabolic response to cooling was also investigated in the semi-precocial Brown Noddy embryos at different stages of development. In contract to precocial chickens, the semi-precocial Noddy had no apparent homeothermic response before hatching.(6) In conjuction wiht studies on embryonic thermoregulation, the basic experiments were made to aim at forwarding the present study to a project elucidating the circulatory functions of developing avian embryos. Less