Domer Daniel A, Erickson Rebecca L, Petty Joann M, Bergdall Valerie K, Hickman-Davis Judy M
University Laboratory Animal Resources, The Ohio State University, Columbus, Ohio, USA.
J Am Assoc Lab Anim Sci. 2012 Mar;51(2):162-9.
The goal of this study was to evaluate the effectiveness of a new proprietary processed corncob bedding material (PCC)compared with standard corncob in ventilated and static mouse housing systems. Intracage ammonia levels, bacterial growth, and absorptive capacity of bedding were measured for cages of C57BL/6 mice under nonautoclaved and autoclaved conditions on static and ventilated racks in a barrier facility. Ammonia concentration was measured daily, and cages were removed from the study when measurements reached or exceeded 25 ppm. Bacterial growth in bedding was quantified and speciated before exposure to mice and at the time of cage removal. The absorptive capacity of all bedding material was determined under autoclaved and nonautoclaved conditions. Ventilated cages with PCC or autoclaved corncob took longer to reach ammonia concentrations of 25 ppm than did those with corncob or autoclaved PCC; PCC-filled cages remained below 25 ppm NH3 for at least 3 wk. The type of bedding material did not affect the number of days required to reach 25 ppm in static cages. Compared with other bedding types in the absence of mice, 1/4-in. PCC had a lower and 1/8-in. corncob a higher bacterial load. Autoclaving altered the absorptive capacity of 1/4-in. bedding materials, and for 1/8-in. bedding, corncob was more absorptive than PCC regardless of autoclaving. The results of this study indicate that PCC is comparable to autoclaved corncob in controlling intracage ammonia levels, and a cage-change interval of 3 wk is possible when ventilated cages are used with this bedding.
本研究的目的是评估一种新型专利加工玉米芯垫料（PCC）与标准玉米芯相比，在通风和静态小鼠饲养系统中的效果。在屏障设施的静态和通风架上，对C57BL/6小鼠笼舍在非高压灭菌和高压灭菌条件下的笼内氨水平、细菌生长和垫料吸收能力进行了测量。每天测量氨浓度，当测量值达到或超过25 ppm时，将笼子从研究中移除。在暴露于小鼠之前和笼子移除时，对垫料中的细菌生长进行定量和鉴定。在高压灭菌和非高压灭菌条件下测定了所有垫料的吸收能力。与使用玉米芯或高压灭菌PCC的笼子相比，使用PCC或高压灭菌玉米芯的通风笼子达到25 ppm氨浓度所需的时间更长；填充PCC的笼子在至少3周内氨浓度保持在25 ppm以下。垫料类型对静态笼子达到25 ppm所需的天数没有影响。与没有小鼠时的其他垫料类型相比，1/4英寸的PCC细菌载量较低，1/8英寸的玉米芯细菌载量较高。高压灭菌改变了1/4英寸垫料的吸收能力，对于1/8英寸的垫料，无论是否高压灭菌，玉米芯的吸收能力都比PCC强。本研究结果表明，PCC在控制笼内氨水平方面与高压灭菌玉米芯相当，当通风笼子使用这种垫料时，3周的换笼间隔是可行的。
