In addition to being a complete waste of money, puppy and kitten replacement formulas will also kill orphaned wild critters, squirrels in particular. Squirrels do not have the ability to digest albumin (which is a protein found in eggs, commonly found in most manufactured replacement milks). Here is a simple, dirt cheap, do it yourself recipe that is tried and true.
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This recipe is originally from the Bird Watcher's Digest & was shared on our Budget101 Discussion list, (no longer in service). ...