Mohr E G, Krzywanek H
Department of Veterinary Physiology, Free University of Berlin, Germany.
Physiol Behav. 1995 Feb;57(2):339-47. doi: 10.1016/0031-9384(94)00273-8.
To determine the influence of various feeding schedules (different times of feeding, times without feeding) on the time course of heart rate (HR), electric activity of cervical muscles (EMG), motor activity (ACT) and body temperature (TB) in ruminants, 5 sheep were equipped with portable dataloggers able to register and store these variables every 30s. Under controlled housing conditions, the temporal changes which occur were registered for 12 consecutive days each period at least. During experimental periods with various feeding times HR and TB were within the physiological range and all variables showed pronounced peaks which were associated with the time of food presentation. On days without feeding TB (38.8 degrees C) was at the lower limit of this range and HR (56 bpm) was extremely below this limit; similar peaks as before were not detectable. The circadian rhythms of HR and TB seemed not to be influenced by the different times of feeding, but there were hints, that photic or social factors could act as a zeitgeber for ACT. Remarkable was the fact that the downregulation of the food induced rises of HR and TB was determined by the phase angle of the circadian rhythm.
为了确定不同的饲喂时间表（不同的喂食时间、禁食时间）对反刍动物心率（HR）、颈部肌肉电活动（EMG）、运动活动（ACT）和体温（TB）随时间变化的影响，给5只绵羊配备了便携式数据记录器，能够每30秒记录并存储这些变量。在可控的饲养条件下，每个时间段至少连续12天记录所发生的时间变化。在不同喂食时间的实验期间，心率和体温处于生理范围内，所有变量均出现明显峰值，且这些峰值与喂食时间相关。在禁食日，体温（38.8摄氏度）处于该范围的下限，心率（56次/分钟）极低，低于该下限；之前类似的峰值未被检测到。心率和体温的昼夜节律似乎不受不同喂食时间的影响，但有迹象表明，光照或社会因素可能作为活动的授时因子。值得注意的是，食物引起的心率和体温升高的下调由昼夜节律的相位角决定。
