Table 1. Backcrossing Outcomes.
| N | Females superovulated,n | Recipients (embryos transferred) n | Pups (pups kept),n | Tg positive females, n | % C57BL/6J backgrounda | Duration of generation, days | Mice used, nb |
|---|---|---|---|---|---|---|---|
| N1 | 5 | 2 (10, 12) | 2 (2) | 2 | 87.8/87.6 | 47 | 9 |
| N2 | 2 | 2 (10, 10) | 9 (2) | 3 | 92.95/94.13/93.1 | 52 | 10 |
| N3 | 2 | 3 (12, 12, 13) | 3 (1) | 0 | n/a | 88 | 18 |
| N3ac | n/a | 3 | 24 (6) | 2 | 97.38/96.6 | ||
| N4 | 2 | 2 (10, 11) | 9 (2) | 2 | 98.03/98.43 | 49 | 10 |
| N4ad | n/a | 1 | 3 (3) | 1 | 98.83 | (69) | |
| N5 | 2 | 3 (10, 10, 9) | 12 (4) | 2 (males) | 99.3/99.3 | 55 | 9 |
aAnimals selected for next generation marked bold
bNot including C57BL/6J stud males or tg-negative pups not kept to weaning.
cN2 tg-positive males were naturally mated with B6 females.
dN3 tg-positive male was naturally mated with B6 female.