Frequency of spontaneous diabetes in LEW.1WR1 rats
| Year . | 2000 . | 2001 . | 2002 . | 2003 . | 2004 . | Total . |
|---|---|---|---|---|---|---|
| Males | 6 | 6 | 9 | 8 | 0 | 29 |
| Females | 4 | 6 | 17 | 14 | 5 | 46 |
| Age at onset (days) | 49–74 | 50–79 | 50–80 | 49–86 | 46–76 | 75 |
| Year . | 2000 . | 2001 . | 2002 . | 2003 . | 2004 . | Total . |
|---|---|---|---|---|---|---|
| Males | 6 | 6 | 9 | 8 | 0 | 29 |
| Females | 4 | 6 | 17 | 14 | 5 | 46 |
| Age at onset (days) | 49–74 | 50–79 | 50–80 | 49–86 | 46–76 | 75 |
No diabetes was observed in the closed colony of LEW.1WR1 rats at BRM from the time of acquisition in 1989 until 2000. Beginning in February 2000, and continuing to the present, spontaneous diabetes has been detected periodically, as indicated. The exact incidence of diabetes cannot be calculated because the size of this commercial breeding colony varies continuously and animals are removed at different ages, but the 75 diabetic animals detected represent ∼2% of the total number of LEW.1WR1 rats weaned in the colony from 2000 through 2004.