How to take care of abandoned baby bird?

It depends on what kind of bird it is. You need a handraising formula not a puppy formula. They make special ones for birds. I suggest looking for pics of the bird on the net and then re posting your question and then you will get a better answer as to the spcific type of bird it is! I would go to the nearest pet store and take the bird someont there might know what kind it is and then refer you to the correct mix to buy.  more