外环境湿度和换气次数对独立通风笼盒微环境湿度和氨浓度的影响

目的：评估在独立通风笼盒（IVC）所处环境不同湿度条件下，IVC 不同换气次数时，大、小鼠 IVC 微环境湿度和氨浓度的变化。方法屏障环境内，以7 d 为换笼周期，分别设定室内环境低湿（40％）、中湿（50％）、高湿（60％），IVC 换气次数为40次/h、60次/h 时，对3个品牌大、小鼠 IVC 微环境进行测定，观察笼盒内湿度和氨浓度的变化。结果当室内环境为低湿条件，小鼠和大鼠 IVC 换气次数设置为40次/h 时；当室内环境为中湿条件，小鼠换气次数设置为40次/h、大鼠换气次数设置为60次/h 时；当室内环境为高湿条件，小鼠换气次数设置为60次/h 时，笼盒内微环境均基本能够满足 GB14925-2010对湿度和氨浓度的要求。而在高湿情况下，即使大鼠 IVC换气次数置为60次/h 也不能满足要求。结论室内环境湿度和 IVC 换气次数是影响 IVC 微环境的关键指标，只有依据室内环境条件合理设置 IVC 换气次数才能较好地维护 IVC 微环境和达到有效管理的目的。

Effect of environmental humidity and ventilation rate on the microenvironmental humidity and ammonia concentration in individually ventilated cages (IVC)

Objective To assess the changes of humidity and ammonia concentration in rat and mouse individually ventilated cages (IVC) based on macroenvironmental humidity and air ventilation changes. Methods Three kinds of rat and mouse IVC in barrier facilities were set as research objective. The changes of micronvironmental humidity and ammonia concentration at 40 times/h and 60 times/h air changes were detected continuously for a 7-days-cycle relative to low (40%), moderate (50%), and high (60%) macroenvironmental humidity. Results Mouse and rat IVC with 40 times/h air changes under low macroenvironmental humidity condition, mouse IVC with 40 times/h and rat IVC with 60 times/h air changes under moderate macroenvironmental humidity condition, mouse IVC with 60 times/h air changes under high macroenvironmental humidity condition, basically meet the GB14925-2010 requirements. While under macroenvironmental high humidity condition, the microenvironments of rat and mouse IVC with 60 times/h air changes could not satisfy the requirements. Conclusions The environmental humidity and ventilation frequency are the key index of IVC microenvironment. Only on the basis of external environment conditions to set up reasonable IVC ventilation frequency in order to better maintain the IVC microenvironment so that to achieve the goal of effective management.