Development of heart rate in the precocial king quail Coturnix chinensis.
Development of heart rate in the precocial king quail Coturnix chinensis.
复制标题
早熟王鹌鹑心率的发展。
DOI：
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发表时间：
1998
影响因子：
2.8
通讯作者：
Hiroshi Tazawa
中科院分区：
文献类型：
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作者：
James T. Pearson;Masaoki Tsudzuki;Y. Nakane;R. Akiyama;Hiroshi Tazawa
我们的目的是研究心脏率（fh）的变化，在胚胎和孵化后的最小的早熟鸟类物种，鹌鹑。在实验一中，重复测量的平均fh为个别鹌鹑的心冲击图（BCG）在孵化期间，并通过压电薄膜和心电图（ECG）在posthatching期间（休息和热中性条件）。在孵化的后半段和孵化后的第一周，所有胚胎的平均卵泡发育率都有所增加，但少数胚胎在内部穿孔前经历了一段非常短暂的卵泡发育率下降。在第一周后，鹌鹑的fh维持在较高的水平（550-650次/min），然后随着年龄和体质量的增加而下降。最大的fh鹌鹑小鸡代表一个更大的posthatching增加fh比发现在较大的早熟鸡，这种差异是由于更高的要求，在小的身体质量的鹌鹑的体温调节。试验Ⅱ用心电图记录鹌鹑胚胎（2-16 d）的平均fh，并测定胚胎期、去卵黄胚胎质量（湿重和干重）和含水量。在整个孵育过程中，平均胚胎生长速率与胚胎质量呈线性关系，但在内部穿刺前一天除外，此时少数胚胎的胚胎生长速率下降到低于此线性关系。对晚孵胚胎、幼鹌鹑和成年鹌鹑的瞬时荧光强度的测量均显示荧光强度的自发波动。首次在一种鸟类中发现了两个主要的频率成分。幼鸡和成年鹌鹑的低频（平均0.09 Hz，12.6 s）和高频（1.4 Hz，0.9 s）振荡被检测到，并被认为是反映压力反射介导的fh和呼吸性窦性心律失常，分别。
Our aim was to examine changes in heart rate (fh) during the embryonic and posthatching periods of the smallest precocial avian species, Coturnix chinensis. In experiment I, repeated measurements of mean fh were made for individual quail by ballistocardiogram (BCG) during incubation, and by both piezo-electric film and electrocardiogram (ECG) during the posthatching period (resting and thermoneutral conditions). Mean fh of all embryos increased during the second half of incubation and the first week posthatching, but a few embryos experienced a very brief period of decreased fh prior to internal pipping. After the first week, fh of posthatching quail was maintained at high levels (550-650 beats min-1), then decreased with age and increase in body mass. The maximal fh of quail chicks represents a greater posthatching increase in fh than is found in larger precocial chickens, this difference being attributable to the higher demands of thermoregulation at small body masses in the quail. In experiment II, the mean fh of quail embryos (day 2-16) was recorded by ECG, and embryonic stage, yolk-free embryo mass (wet and dry) and water content were measured. Mean fh was linearly related to embryo mass throughout incubation, except on the day prior to internal pipping, when the fh of a few embryos declined below this linear relationship. Measurements of instantaneous fh of late incubation embryos, young and adult quail all showed spontaneous fluctuations in fh. Two main frequency components of fh fluctuations were identified for the first time in an avian species. Low-frequency (mean 0.09 Hz, 12.6 s) and high-frequency (1.4 Hz, 0.9 s) oscillations in both young chicks and adult quail were detected and are considered to reflect baroreflex mediation of fh and respiratory sinus arrhythmia, respectively.