Do you think all those single socks that go missing all over the world are inside Cocker spaniels? 
YES - well at least in our house.
Millie's gobbled two down whole, the 1st came up after 2 days, the 2nd came up after being given an injection by the vet to make her sick. (she'd eaten it 2 days earlier and started being sick, and as it was the Friday before xmas the vet didn't want to leave it and have a possible emergency over the xmas break)
I think she may have eaten another one yesterday - Didn't see her eat it but think there was one more sock in the washing pile than was there

We're keeping a close watch on her. How long after the event would salt water possibly do the trick?