From: A review of factors influencing litter size in Irish sows
Age of eggs at fertilisation (hours)
Percentage of eggs normally fertilised
Number of viable embryos at day 25
0
90.8
12.0
4
92.1
11.7
8
94.6
8.7
12
70.3
6.8
16
48.3
4.8
20
50.9
5.0