Here is what I think will retire from the animal lines:
maybe the adult croc
the rhino
maybe the giraffe female and calf
maybe the kangaroo
camel
tigers (white or orange I don't know)
the older squirrel
badger cubs
hedgehog adult
maybe the rabbit
bald eagle
one of the raccoons
white tail deer family
the sitting brown rabbit
the sitting black and white cat
the standing gray cat
maybe the pigs
maybe the chickens
I have no idea on the horses, they seem to be a little random when it comes to that portion
Husky
a few from the Retriever family
maybe some from the Labrador family
the dwarf lop ear rabbit
the tortoise
and maybe the guinea pig
As far as replacements go, I think it is highly likely that the figures that have the ability to be "cute" and appeal their main market will be replaced. For instance (if this figure is retired) the guinea pig, deer family, giraffe family etc. And again, these are only guesses and wishes on what I would like to be retired and/or replaced. I hope the new figures are released soon, anyone know when?