6REEB C,JENES R,BEARG D,et al. Microenvironment in ventilated animal cages with differing ventilation rates, mice populations, and frequency of bedding changes[J]. Contemp Top Lab Anita Sci ,1998,37(2) :43 -49.
7WIRTH H. Criteria for the evaluation of laboratory animal bedding[J]. Laboratory Animais ,1983,17:81.
8HSTON W E. Testing for dessible effects of cedar wood shavings and diet on occurrence of mammary gland tumors and hepatomas in C3H-A-vy and C3H-Avy-fB mice[J]. Journal on the Naional Cacer Institute,19?5,54(4) : 1011.
9POTGIETER F J, WILKE P I. Laboratory animal bedding:A review of wood and wood constituents as a oossible source of external variables that wtdd influence experimental results[J]. Animal Technology, 1992, 43 (2) :65.