摘要：
目的 动态检测屏障环境中用于小鼠的新型排气通风笼具(EVC)的微环境指标.方法 测定两种饲养小鼠的EVC笼盒内通风风速和笼盒体积,计算笼盒换气次数.使用刨花垫料时换笼周期设置为7d,使用玉米芯垫料时换笼周期设置为14d,分别在每种换笼周期内每日连续检测笼盒内的噪声、压差、温度、相对湿度和氨浓度指标.结果 两种EVC笼盒内噪声分别为54.2士3.4 db和55.6士4.1 db,笼盒与屏障环境压差分别为-23.1±9.2 Pa和-27.5±11.6 Pa.从换笼周期第1日起,饲养小鼠的EVC笼盒内的温度差、相对湿度和氨浓度都呈现逐步升高的趋势;使用刨花垫料的两种EVC笼盒其第6日的氨浓度分别达到1.28±0.08 mg/m3和1.33±0.15 mg/m3,笼盒内温度分别为23.5±0.27°C和22.8±0.15°C,湿度分别为67.8％±2.2％和70.2％±1.1％;而使用玉米芯垫料的两种EVC笼盒内第12日达到氨浓度分别为1.95±0.46 mg/m3和2.17±0.33 mg/m3,笼盒内温度分别为23.8±0.4°C和24.1±0.2°C,湿度分别为70.3％±1.8％和69.6％±1.8％.结论 使用EVC笼盒饲养小鼠时,刨花垫料采取每6日换笼及玉米芯垫料采取每12日换笼的方案,可以使笼盒内的微环境指标:噪声、压差、温度、湿度和氨浓度,均符合国标GB 14925-2010要求.提示EVC与玉米芯垫料相结合,有助于维持笼盒内微环境稳定,可用于实验动物的生产和相关研究中.%Objective To dynamically assess the micro-environmental changes of the new type exhaust ventilated closed-system cage (EVC)for mice.Methods Based on the measurement of ventilation velocity and volume in EVC cages with mice,the air exchange rate were calculated.The parameters of noise,temperature,differential air pressure,relative humidity,micro-environmental ammonia concentration and macro-environmental ammonia concentration were detected continuously for a 7-day-cycle with wooden shaving bedding and for a 14-day-cycle with corncob bedding.Results The noise in two type EVC were 54.2 ± 3.4 db and 55.6 ± 4.1 db.The differential pressure between EVC and room were-23.1 ± 9.2 Pa and-27.5 ± 11.6 Pa respectively.Since the first day of caging change cycle,the micro-environmental temperature,humidity and ammonia concentrations has raised gradually in cages.On the sixth day,ammonia concentration in two type of cages reached 1.28 ± 0.08 mg/m3 and 1.33 ± 0.15 mg/m3 respectively with wood shaving beddings,the temperature were 23.5 ± 0.27 °C and 22.8 ± 0.15 °C respectively,the humidity were 67.8％ ± 2.2％ and 70.2％ ± 1.1％ respectively.On the twelfth day,ammonia concentration in cages reached 1.95 ± 0.46 mg/m3 and 2.17 ± 0.33 mg/m3 with corncob beddings,the temperature were 23.8 ± 0.4 °C and 24.1 ± 0.2 °C,and the humidity were 70.3％ ± 1.8％ and 69.6％ ± 1.8％ respectively.Conclusions Based on the conditions of current experiment,during 6-day and 12-day caging change-cycle respectively,the micro-environmental parameters,such as:noise,differential air pressure,temperature,humidity and ammonia concentrations met the GB 14925-2010 requirements.EVC system with corncob bedding are highly recommended to maintain a stable micro-environment,that could be used in animal research and animal production.
