Jilge B
Laboratory Animals Research Unit, University of Ulm, Germany.
Physiol Behav. 1995 Jul;58(1):131-40. doi: 10.1016/0031-9384(95)00006-5.
We have monitored parturition and different behavioral rhythms of does, the activity of suckling pups and behavioral rhythms of rabbits after weaning until adulthood. All animals were living in continuous light conditions (LL). As a consequence of the free-run of the does parturition, which takes place during the resting period of the animal, occurred at almost any time of the day. The once/day nursing was advanced during the first 7-10 days until it was in synchrony with the time of main activity. The pups significantly anticipated nursing by day 5: the 60 min bin prior to nursing exceeded the 24-h mean by 63 +/- 30%. The anticipatory activity (AA) was entrained by an artificial nursing schedule of T = 24 h, the 60 min bin prior to nursing exceeding the 24-h mean by 123 +/- 50%. Since AA persisted during a 48 h fast, its phase is controlled endogenously. At weaning behavioral rhythms of rabbits free-ran with a main tau < 24 h (average 23:35 +/- 17'), period length extending with increasing age. 7/10 animals had an additional component > 24 h (average: 24:24 +/- 16') which became increasingly dominant, the components < 24 h fading out within 30 days after weaning. Between days 340-350 a stable period length of 24:35 +/- 8' and a consolidation of the circadian rhythms was attained. These results confirm that during the first days of the rabbit's life the circadian system is controlled by a feeding entrainable oscillator, the light entrainable oscillators taking over control later.
我们监测了母兔的分娩过程和不同行为节律、哺乳幼兔的活动以及断奶后直至成年的家兔行为节律。所有动物均饲养在持续光照条件（LL）下。由于母兔分娩处于自由运行状态，且发生在动物的休息期，所以几乎在一天中的任何时间都可能分娩。在最初的7 - 10天内，每天一次的哺乳时间提前，直至与主要活动时间同步。幼兔在第5天时显著提前预期哺乳：哺乳前60分钟时段超过24小时平均值63±30%。预期活动（AA）被T = 24小时的人工哺乳时间表所调节，哺乳前60分钟时段超过24小时平均值123±50%。由于AA在48小时禁食期间持续存在，其相位受内源性控制。断奶时，家兔的行为节律自由运行，主要周期<24小时（平均23:35±17'），周期长度随年龄增长而延长。7/10的动物还有一个>24小时的额外成分（平均：24:24±16'），且该成分逐渐占主导地位，<24小时的成分在断奶后30天内逐渐消失。在第340 - 350天之间，达到了24:35±8'的稳定周期长度和昼夜节律的巩固。这些结果证实，在兔子生命的最初几天，昼夜节律系统由一个可被进食调节的振荡器控制，之后由可被光照调节的振荡器接管控制。
