We performed OS counts in the mid-peripheral retinas of 4-week-old rd1 mice, where cone density is the highest, and found similar numbers for C3H/HeOu (8.43±0.9 k/mm 2, n=6) and FVB/N (7.08±0.54 k/mm 2, n=6) mice that did not significantly differ from the counts of their seeing congenics (C3H-Pde6b + (9.45±0.75 k/mm 2, n=5; FVB-Pde6b + 8.72±0.68 k/mm 2, n=5).
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