Wong M A, Oace S M
Lab Anim Sci. 1981 Aug;31(4):362-5.
Food consumption, fecal production, and excretion of an orally administered, nonabsorbed fecal marker were measured in rats housed in continuously-lighted animal quarters or in a room with alternating 12-hour light and dark periods. After a 3-week adaptation period, animals kept in alternate-lighting consumed 75% of their 24-hour food intake and produced 61% of their 24-hour fecal output during the 12 dark hours. In rats subjected to continuous-lighting, food intake and fecal output during the 12 hours corresponding to the dark in alternate-lighting were only 39% and 46% of the 24-hour totals, respectively. A radioactive chromic chloride fecal marker was presented for voluntary consumption to half of the animals in the morning and to the other half in the evening in each lighting situation. Rats offered the 51Cr dose at the beginning of their more active feeding period excreted about 40% of the radioactivity in each of the first two 12-hour collection periods. When the fecal marker was offered at the beginning of the less active feeding period, less than 10% of the 51Cr appeared in the first 12-hour collection, and over 70% was excreted during the second 12-hour collection. Thus, changes in food consumption patterns that occurred with alteration of room lighting were accompanied by parallel changes in fecal production and gastrointestinal transit rates.
在持续光照的动物饲养间或有12小时明暗交替周期的房间中饲养的大鼠，测量其食物摄入量、粪便产生量以及口服非吸收性粪便标记物的排泄情况。经过3周的适应期后，处于交替光照环境中的动物在12小时黑暗期内消耗了其24小时食物摄入量的75%，产生了其24小时粪便排出量的61%。在持续光照的大鼠中，与交替光照环境中的黑暗期相对应的12小时内，食物摄入量和粪便排出量分别仅为24小时总量的39%和46%。在每种光照情况下，分别在上午给一半动物、晚上给另一半动物提供放射性氯化铬粪便标记物以供其自愿食用。在进食活动较为活跃的时期开始时给予51Cr剂量的大鼠，在前两个12小时收集期的每一期中排泄出约40%的放射性物质。当在进食活动不太活跃的时期开始时提供粪便标记物时，在第一个12小时收集期内出现的51Cr不到10%，而在第二个12小时收集期内排泄出超过70%。因此，随着房间光照变化而发生的食物消费模式变化伴随着粪便产生和胃肠转运速率的平行变化。
