Effect Of Cage Size And Environment Enrichment On Sleep Behavior Rhythmicity And Offspring Of Female Mice

Enrichments in breeding environment increased animal life quality and welfare. The environment differences during pregnancy and lactation affected growth and survival rate of offsprings. This research focused on the effect of environment on female mice throw physiological, growth of offspring and circadian Rhythmicity of sleep behavior. To study the effect of environment on circadian Rhythmicity it is needed to observe behavior of female mice for a long and uninterrupted period, thus a new mice behavior video capture system were developed.There were two parts in this study. The design of mice behavior video monitoring system was described in the first part, include the video-capture computer system and data storage system. Then, described the design and evolution process of three mice observation cages. The three mice observation cages were named as OA2, OB2,OC, their sizes were 20x30 x 25cm3, 10x20 x 25cm3, 40x60 x 30cm3.In the second part, the effect of environment on female mice threw two experiment stages was investigated. The laboratory environment was set as: 14h-light and 10h-dark, temperature maintained at 21±2oC, humidity maintained at 63-67%, no sound and other personnel interruption existed.In the first experimental stage, the effect of environment on female mice in normal state was studied. 24 virgin mice of Kun Ming strain were chosen. The age of the mice was about 45 days and their body weights were around 29±2g. They were raised in OA2, OB2, OC cages for 30 days. Then, mice sleep behavior and wheel-rolling behaviors in 5 environments were observed. The 5 environments included OA2, OB2 and OC observation cages and two extensions of OA2. In each 30 mice were observed environment for one whole day. Their sleep and wheel-rolling behavior were analyzed. After that, 4 environments were chosen to observe sleep behavior of 24 female mice for 5 days.In the second experimental stage, the effect of environment on female mice during pregnancy and lactation were studied. At first, 42 Kun Ming virgin mice were chosen whose body were weight about 29±2g, the changes of their body weight were recorded, birth-rate, offspring number, survival rate of offspring and sex-ratio of offspring were recorded. After that, chose OA2 observation cage, record sleep and accompany behavior of 4 virgin mice during pregnancy and lactation for 25 days. In video analysis, 5 minutes were set for a time sampling. Thus one day was divided into 288 segments.The results showed that the body weights of female mice raised in three kinds of observation cages for more than 10 days were significantly different. Mice in OB2 were heavier than those in OA2 and OC.