The Occidental Low- and High-Saccharin-Consuming rats (respectively, LoS and HiS) have been selectively bred for decades to study the relationship between taste and behaviors in and beyond the ingestive domain. Whether the saccharin phenotype is associated with behavioral periodicities tied to reproductive status is not known. Here we describe for the first time variation across the estrous cycle in chow intake and wheel running by LoS and HiS rats. This study also shed light on why rats, humans, and some other mammals eat less and become more active as fertility increases. Wheel running increases when eating is reduced through restricted chow access, more so in LoS rats than in HiS rats (Dess et al., 2000). If the decrease in food intake from diestrus through estrus causes the increase in running (Eat Less → Run More hypothesis, ELRM), then the running peak should follow the eating nadir and be greater in LoS rats. Bayesian cyclic regression showed that estrous cycles were shorter in LoS rats than in HiS rats; implications are discussed. Contrary to ELRM, the running peak did not follow the eating nadir, and cycle amplitude did not distinguish LoS rats from HiS rats. These results indirectly support the No Time To Eat hypothesis (Fessler, 2003), according to which the periovulatory eating nadir and running peak reflect fitness-enhancing consequences of shifts away from eating and toward mating as fertility increases.

西方低糖精和高糖精消耗大鼠（分别为 LoS 和 HiS）几十年来一直被选择性饲养，以研究摄食领域内外的味觉与行为之间的关系。尚不清楚糖精表型是否与与生殖状态相关的行为周期性有关。在这里，我们首次描述了 LoS 和 HiS 大鼠在食物摄入和车轮运行中发情周期的变化。这项研究还阐明了为什么老鼠、人类和其他一些哺乳动物会随着生育能力的增加而吃得更少并且变得更加活跃。当通过限制食物进入减少进食时，车轮跑动会增加，LoS 大鼠比 HiS 大鼠更是如此（Dess 等，2000）。如果从发情期到发情期食物摄入减少导致跑步增加（Eat Less → Run More假设，ELRM），那么跑步峰值应该跟随进食最低点，并且在 LoS 大鼠中更大。贝叶斯循环回归显示LoS大鼠的动情周期比HiS大鼠短；影响进行了讨论。与 ELRM 不同的是，跑步峰值不遵循进食最低点，并且周期幅度不能区分 LoS 大鼠和 HiS 大鼠。这些结果间接支持没有时间进食假说（Fessler，2003），根据该假说，排卵期进食最低点和跑步高峰反映了随着生育能力的增加从进食转向交配的健康增强后果。和周期幅度不能区分 LoS 大鼠和 HiS 大鼠。这些结果间接支持没有时间进食假说（Fessler，2003），根据该假说，排卵期进食最低点和跑步高峰反映了随着生育能力的增加从进食转向交配的健康增强后果。和周期幅度不能区分 LoS 大鼠和 HiS 大鼠。这些结果间接支持了没有时间进食假说（Fessler，2003），根据该假说，排卵期进食最低点和跑步高峰反映了随着生育能力的增加从进食转向交配的适应性增强结果。