I have returned cats after a longer period - I am set up to foster feral-acting mothers that have come into the shelter in a trap, either with newborn kittens or have given birth in the shelter, and that can not go to a regular kitten foster. I keep them in a large crate setup (if possible, two connected) until the kittens are weaned. Mothers that are not adoptable will be returned unless there are circumstances where that is not possible. I do not have any success/failure numbers, because these are return to field cats that come in through the city's animal control.
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