Here are the conditions:
Cage will be on a 3 and a half foot high table.
I have a terrier, who seems to get along fine with the piggies. I always keep them separated, though. When the piggies have floor time, Louie goes in his room.
The table is tall enough that he can barely get his front paws on it. With the added height of the cage walls, I don't see any conceivable way he could get into it.
What I *am* worried about, though, is the guinea pigs getting OUT of the cage. Would it be possible for them to get over the walls?
Let me know what you all think!
There is no such thing as too much safety when there is a dog in the family. The lids aren't that expensive (in the $40 department) and are VERY easy to operate. The only restriction it will add is for making multiple levels, but single story cages are typically preferred anyway. It's rare but possible for pigs to scale full height grids. Dogs, however, are creative wee beasties.
I have a terrier mix named Louie and when he was younger, I would never leave him alone in the same room as the pigs. Now he is over 10 and I have a cage up on a table away from anything he can jump on to get to them. He is now more interested in sitting by the rat cage and watching them.