Data on long-term survival of the NOD/Shi-scid IL-2Rγ^null (NOG) mouse in two facilities

The objective of this study was to investigate an appropriate observation period for an evaluation of tumorigenicity in NOD/Shi-scid IL-2 Rγ^null (NOG) mice. At SNBL, 19 male and 19 female NOG mice were observed the general condition from 7 weeks old up to 68 weeks old and at FBRI, 7 male and 16 female NOG mice were observed the general condition throughout the lifespan from 7 weeks old. The survival rate started to decline rapidly around 54 to 56 weeks of age in both facilities without a facility difference. Based on these survival data, it seems reasonable to terminate a tumorigenicity study at 52 weeks of age.